A preliminary study on the effects of elevated CO2 on aphid resistance of Tugela Dn and the population dynamics of the Russian wheat aphid (Homoptera: Aphididae), Diuraphis noxia
- Authors: Mundondo, Daphine
- Date: 2015
- Language: English
- Type: Thesis , Masters , MSc (Biochemistry)
- Identifier: vital:11402 , http://hdl.handle.net/10353/d1020244
- Description: Food security is of major importance due to the increasing world population with 8.9 billion people expected by 2050 (Cohen, 2003). Diuraphis noxia (RWA), have caused aggravating, massive losses to wheat farmers in many areas of the world. If unchecked, RWA are able to destroy plants resulting in major economic impacts (Botha, 2013). Due to ineffective use of other control methods, the Small Grains Institute in Bethlehem, South Africa, have therefore developed resistant cultivars to the known RWA subtypes over the past decades through intensive breeding programmes (Tolmay et al., 2006). Climate change has however become a major factor threatening food security especially with the observed increase in CO2 from less than 300 ppm in pre-industrial period to the current 385 ppm and is predicted to reach 550 ppm by 2050 (IPCC, 2007; Meehl et al., 2007). Elevated CO2 concentration may affect individual species of a community hence the need to understand the wheat-aphid interactions. In this study, population growth rates and virulence of RWA SA1 at ambient (385 ppm) and elevated (450 ppm) CO2 concentration were evaluated on two wheat cultivars: Tugela Dn (resistant) and Scheepers (susceptible). Fluorescence microscopy techniques using aniline blue were used to investigate feeding related damage caused by RWA SA1 through an examination of callose deposition at the two CO2 concentration. A two-dimensional gel electrophoresis method was developed in order to determine the effect of RWA SA1 on the wheat cultivars proteome at the two CO2 concentration. Differentially expressed proteins that were up or down regulated more than two fold were identified using PDQuestTM Basic 2D Gel analysis software. Populations of RWA SA1 increased significantly on the two wheat cultivars at both CO2 concentration. Although the population growth rate for RWA SA1 on both cultivars was generally exponential at all treatments, growth at elevated CO2 concentration was noticeably faster with populations increasing 3 fold in 14 days as compared to the 2 times at ambient CO2 concentration. Hence, both cultivars provided a better quality host for RWA SA1 at 450 ppm than 385 ppm. There was no significant difference between RWA SA1 population on Tugela Dn and on Scheepers at elevated CO2 concentration on day 14 after infestation which means there was a change in the resistance mechanism in Tugela Dn at this condition. Approximately 70% of the total leaf showed chlorosis by 21 days of aphid infestation for both cultivars although the susceptible cultivar was more vulnerable. There was low callose deposition in the controls (uninfested plants) but heavy callose in infested plants due to aphid feeding. A proteomics approach was used as a pilot study to investigate whether it would be possible to identify the changes in the resistance mechanism during aphid infestation under elevated CO2 levels. The major changes in the proteome of the control group (uninfested Tugela Dn at ambient versus elevated CO2 concentration) occurred in the early events (day 1-7) in the molecular weight range of approximately 25 kDa to 55 kDa are mainly within the basic to neutral pH range. This was suggested to be a result of mechanisms to adjust to the CO2 concentration. Elevated CO2 results in instant higher photosynthetic rates and C:N ratios as well as changes in expression levels of SA-dependant defense genes (Lindroth 1995; Hughes and Bazzaz, 2001; Sun et al., 2013). Because most of these changes are directly regulated by proteins, it is expected that the most differential protein expression will occur immediately after the atmospheric changes (early events) as was shown in the study. Infested plants under elevated and ambient conditions showed that the stress conditions gave rise to differentially regulated proteins within the wheat proteome. Most changes occurred elevated CO2 levels. It can be suggested that the changes were a result of differentially regulated plant defence proteins which fall in this range (25 kDa - 80 kDa) such as peroxidases, chitinases and β-1.3-glucanases as well as protein kinases, heat-shock proteins and photosynthetic proteins. These results indicate that there has been changes in the resistance due to elevated CO2 because of the evident changes in the proteome. If so, then the results will be similar to those documented by Louw (2007) where up-regulation was due to putative storage proteins, proteins involved in photosynthesis, heat shock proteins and defense proteins. Of course, the pI value and molecular mass of the proteins and the identification of the proteins in these spots, must be determined in future work to specifically identify whether these suggestions are authentic. However, Louw (2007) also reports that the susceptible Betta wheat cultivar, displayed a defence response similar to the HR although it was unable to up-regulate specific defensive proteins against RWA infestation but proteins for broad resistance. Although the changes in the proteins in infested Tugela Dn under elevated CO2 concentration were not accurately identified, the defense mechanism is similar to that portrayed by the susceptible Betta wheat cultivar which shows that the resistance mechanism had been overcome. Because this was a pilot study and preliminary results were obtained due to limited funding and time constraints, suggestions were made on how to further develop the method to obtain statistically significant results.
- Full Text:
- Date Issued: 2015
- Authors: Mundondo, Daphine
- Date: 2015
- Language: English
- Type: Thesis , Masters , MSc (Biochemistry)
- Identifier: vital:11402 , http://hdl.handle.net/10353/d1020244
- Description: Food security is of major importance due to the increasing world population with 8.9 billion people expected by 2050 (Cohen, 2003). Diuraphis noxia (RWA), have caused aggravating, massive losses to wheat farmers in many areas of the world. If unchecked, RWA are able to destroy plants resulting in major economic impacts (Botha, 2013). Due to ineffective use of other control methods, the Small Grains Institute in Bethlehem, South Africa, have therefore developed resistant cultivars to the known RWA subtypes over the past decades through intensive breeding programmes (Tolmay et al., 2006). Climate change has however become a major factor threatening food security especially with the observed increase in CO2 from less than 300 ppm in pre-industrial period to the current 385 ppm and is predicted to reach 550 ppm by 2050 (IPCC, 2007; Meehl et al., 2007). Elevated CO2 concentration may affect individual species of a community hence the need to understand the wheat-aphid interactions. In this study, population growth rates and virulence of RWA SA1 at ambient (385 ppm) and elevated (450 ppm) CO2 concentration were evaluated on two wheat cultivars: Tugela Dn (resistant) and Scheepers (susceptible). Fluorescence microscopy techniques using aniline blue were used to investigate feeding related damage caused by RWA SA1 through an examination of callose deposition at the two CO2 concentration. A two-dimensional gel electrophoresis method was developed in order to determine the effect of RWA SA1 on the wheat cultivars proteome at the two CO2 concentration. Differentially expressed proteins that were up or down regulated more than two fold were identified using PDQuestTM Basic 2D Gel analysis software. Populations of RWA SA1 increased significantly on the two wheat cultivars at both CO2 concentration. Although the population growth rate for RWA SA1 on both cultivars was generally exponential at all treatments, growth at elevated CO2 concentration was noticeably faster with populations increasing 3 fold in 14 days as compared to the 2 times at ambient CO2 concentration. Hence, both cultivars provided a better quality host for RWA SA1 at 450 ppm than 385 ppm. There was no significant difference between RWA SA1 population on Tugela Dn and on Scheepers at elevated CO2 concentration on day 14 after infestation which means there was a change in the resistance mechanism in Tugela Dn at this condition. Approximately 70% of the total leaf showed chlorosis by 21 days of aphid infestation for both cultivars although the susceptible cultivar was more vulnerable. There was low callose deposition in the controls (uninfested plants) but heavy callose in infested plants due to aphid feeding. A proteomics approach was used as a pilot study to investigate whether it would be possible to identify the changes in the resistance mechanism during aphid infestation under elevated CO2 levels. The major changes in the proteome of the control group (uninfested Tugela Dn at ambient versus elevated CO2 concentration) occurred in the early events (day 1-7) in the molecular weight range of approximately 25 kDa to 55 kDa are mainly within the basic to neutral pH range. This was suggested to be a result of mechanisms to adjust to the CO2 concentration. Elevated CO2 results in instant higher photosynthetic rates and C:N ratios as well as changes in expression levels of SA-dependant defense genes (Lindroth 1995; Hughes and Bazzaz, 2001; Sun et al., 2013). Because most of these changes are directly regulated by proteins, it is expected that the most differential protein expression will occur immediately after the atmospheric changes (early events) as was shown in the study. Infested plants under elevated and ambient conditions showed that the stress conditions gave rise to differentially regulated proteins within the wheat proteome. Most changes occurred elevated CO2 levels. It can be suggested that the changes were a result of differentially regulated plant defence proteins which fall in this range (25 kDa - 80 kDa) such as peroxidases, chitinases and β-1.3-glucanases as well as protein kinases, heat-shock proteins and photosynthetic proteins. These results indicate that there has been changes in the resistance due to elevated CO2 because of the evident changes in the proteome. If so, then the results will be similar to those documented by Louw (2007) where up-regulation was due to putative storage proteins, proteins involved in photosynthesis, heat shock proteins and defense proteins. Of course, the pI value and molecular mass of the proteins and the identification of the proteins in these spots, must be determined in future work to specifically identify whether these suggestions are authentic. However, Louw (2007) also reports that the susceptible Betta wheat cultivar, displayed a defence response similar to the HR although it was unable to up-regulate specific defensive proteins against RWA infestation but proteins for broad resistance. Although the changes in the proteins in infested Tugela Dn under elevated CO2 concentration were not accurately identified, the defense mechanism is similar to that portrayed by the susceptible Betta wheat cultivar which shows that the resistance mechanism had been overcome. Because this was a pilot study and preliminary results were obtained due to limited funding and time constraints, suggestions were made on how to further develop the method to obtain statistically significant results.
- Full Text:
- Date Issued: 2015
An evaluation of security issues in cloud-based file sharing technologies
- Authors: Fana, Akhona
- Date: 2015
- Subjects: Cloud computing -- Security measures Computer networks -- Security measures Computer security
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/1841 , vital:27565
- Description: Cloud computing is one of the most promising technologies for backup and data storage that provides flexible access to data. Cloud computing plays a vital role in remote backup. It is so unfortunate that this computing technique has flaws that thrilled and edgy end users in implementing it effectively. These flaws include factors like lack of integrity, confidentiality and privacy to information. A secure cloud is impossible unless the computer-generated environment is appropriately secured. In any form of technology it is always advisable that security challenges must be prior identified and fixed before the implementation of that particular technology. Primarily, this study will focus on finding security issues in cloud computing with the objective of finding concerns like credential theft and session management in the ―Cloud‖. Main arguments like HTTP banner disclosure, Bash ―ShellShock‖ Injection and password issues were discovered during the stages of study implementation. These challenges may provide information that will permit hackers in manipulating and exploiting cloud environment. Identifying credential theft and session management in cloud-based file sharing technologies a mixed method approach was implemented throughout the course of the study due to the nature of study and unity of analysis. Penetration tests were performed as security testing technique. Prevention and guideline of security threats leads to a friendly and authentic world of technology.
- Full Text:
- Date Issued: 2015
- Authors: Fana, Akhona
- Date: 2015
- Subjects: Cloud computing -- Security measures Computer networks -- Security measures Computer security
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/1841 , vital:27565
- Description: Cloud computing is one of the most promising technologies for backup and data storage that provides flexible access to data. Cloud computing plays a vital role in remote backup. It is so unfortunate that this computing technique has flaws that thrilled and edgy end users in implementing it effectively. These flaws include factors like lack of integrity, confidentiality and privacy to information. A secure cloud is impossible unless the computer-generated environment is appropriately secured. In any form of technology it is always advisable that security challenges must be prior identified and fixed before the implementation of that particular technology. Primarily, this study will focus on finding security issues in cloud computing with the objective of finding concerns like credential theft and session management in the ―Cloud‖. Main arguments like HTTP banner disclosure, Bash ―ShellShock‖ Injection and password issues were discovered during the stages of study implementation. These challenges may provide information that will permit hackers in manipulating and exploiting cloud environment. Identifying credential theft and session management in cloud-based file sharing technologies a mixed method approach was implemented throughout the course of the study due to the nature of study and unity of analysis. Penetration tests were performed as security testing technique. Prevention and guideline of security threats leads to a friendly and authentic world of technology.
- Full Text:
- Date Issued: 2015
An investigation of skills and knowledge of women participating in water and food security projects in the Eastern Cape Province: a case of Mbekweni village, Sirhosheni and Lutengele villages
- Authors: Makeleni, Maliviwe
- Date: 2015
- Subjects: Agricultural development projects -- South Africa -- Eastern Cape , Sustainable development -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc Agric (Agricultural Economics)
- Identifier: vital:11235 , http://hdl.handle.net/10353/d1021306 , Agricultural development projects -- South Africa -- Eastern Cape , Sustainable development -- South Africa -- Eastern Cape
- Description: The South African government initiated programmes to ensure that women in agriculture are empowered with sufficient agricultural skills and knowledge to engage in agriculture in order to alleviate poverty for their families and communities. Studies argue that within the agricultural sector, women are not capacitated adequately enough in terms of the skills and knowledge they need to acquire, and particularly as this relates to their ability to have knowledge about more advanced technologies in farming. This includes the most up to date knowledge related to sustainable-development. This study has attempted to investigate skills and knowledge possessed by women participating in water and food security projects in the Eastern Cape. Selected study areas were Mbekweni village located in Whittlesea, Sirhosheni village which is situated in Willowvale and Lutengele village in Port St Johns. The thesis was also aiming to find the skills/knowledge gap amongst the sample so as to come up with recommendations. The data was collected using two semi-structured questionnaires. The first questionnaire was for the main survey which mainly concentrated on the socio-economic information of the respondents. This data were collected from 163 households across three sites using systematic sampling. The second questionnaire was mainly used to gain more in-depth analysis. The data were collected from 30 households across three sites using purposive sampling. Both questionnaires were administered through face-to-face interviews. The majority of respondents have stated that they have basic knowledge and skills in farming, however they need further training on appropriate planting methods for various crops, irrigation scheduling and frequency, application of pesticides and marketing skills. Econometric analysis, through the use of the binomial regression model revealed that education affects the level of knowledge of farmers in selecting appropriate planting methods as well as farmers’ knowledge in determining seed depth of a crop. Gender influences the level of knowledge farmers have when selecting appropriate planting methods. Having extension assistance was recognised to affect farmers’ knowledge in determining irrigation scheduling and intensity. All variables were statistically significant showing a 5% level. The thesis ultimately argues that encouraging support to agricultural extension that respects local-level indigenous farming will increase the food-security potential of residents within the Eastern Cape.
- Full Text:
- Date Issued: 2015
- Authors: Makeleni, Maliviwe
- Date: 2015
- Subjects: Agricultural development projects -- South Africa -- Eastern Cape , Sustainable development -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc Agric (Agricultural Economics)
- Identifier: vital:11235 , http://hdl.handle.net/10353/d1021306 , Agricultural development projects -- South Africa -- Eastern Cape , Sustainable development -- South Africa -- Eastern Cape
- Description: The South African government initiated programmes to ensure that women in agriculture are empowered with sufficient agricultural skills and knowledge to engage in agriculture in order to alleviate poverty for their families and communities. Studies argue that within the agricultural sector, women are not capacitated adequately enough in terms of the skills and knowledge they need to acquire, and particularly as this relates to their ability to have knowledge about more advanced technologies in farming. This includes the most up to date knowledge related to sustainable-development. This study has attempted to investigate skills and knowledge possessed by women participating in water and food security projects in the Eastern Cape. Selected study areas were Mbekweni village located in Whittlesea, Sirhosheni village which is situated in Willowvale and Lutengele village in Port St Johns. The thesis was also aiming to find the skills/knowledge gap amongst the sample so as to come up with recommendations. The data was collected using two semi-structured questionnaires. The first questionnaire was for the main survey which mainly concentrated on the socio-economic information of the respondents. This data were collected from 163 households across three sites using systematic sampling. The second questionnaire was mainly used to gain more in-depth analysis. The data were collected from 30 households across three sites using purposive sampling. Both questionnaires were administered through face-to-face interviews. The majority of respondents have stated that they have basic knowledge and skills in farming, however they need further training on appropriate planting methods for various crops, irrigation scheduling and frequency, application of pesticides and marketing skills. Econometric analysis, through the use of the binomial regression model revealed that education affects the level of knowledge of farmers in selecting appropriate planting methods as well as farmers’ knowledge in determining seed depth of a crop. Gender influences the level of knowledge farmers have when selecting appropriate planting methods. Having extension assistance was recognised to affect farmers’ knowledge in determining irrigation scheduling and intensity. All variables were statistically significant showing a 5% level. The thesis ultimately argues that encouraging support to agricultural extension that respects local-level indigenous farming will increase the food-security potential of residents within the Eastern Cape.
- Full Text:
- Date Issued: 2015
Assessment of bioflocculant production by two marine bacteria isolated from the bottom sediment of marine Algoa Bay
- Authors: Ntozonke, Ncedo
- Date: 2015
- Language: English
- Type: Thesis , Masters , MSc (Microbiology)
- Identifier: vital:11298 , http://hdl.handle.net/10353/d1021290
- Description: Bioflocculants are polymers, mostly, of microbial origin which floc out suspended particles from liquid medium. The ability of these biopolymers to remove suspended particles from solutions is termed bioflocculation, and the efficiency of flocculation activities depends on the characteristics of the flocculants. In comparison with conventionally used flocculants, bioflocculants have the advantage of being safe (no toxic effects known), biodegradable and harmlessness to the environment. The study assessed production of bioflocculant by two marine bacteria from the bottom sediment of marine environment. The 16S rDNA was used for identification, and the two bacteria species were identified as Enterococcus hirae and Bacillus thuringiensis. Factors affecting the production and activity of the bioflocculants produced by these two organisms were studied. The bacteria optimally produced bioflocculant with fructose (91.7%) and urea (91%) as sole carbon and nitrogen sources respectively. Mg2+ (87%) and Ca2+ (86%), likewise, served as best cation sources on the production of the bioflocculant at pH 5(93%). Additionally, the flocculating activity of the bioflocculant increased with the addition of Mg2+ (81%) and Na+ (81%), and the highest flocculating activity was at pH 5 of the kaolin clay. The Fourier transform infrared spectroscopy (FTIR) shows that the bioflocculant is a glycoprotein. The second bacterium (Bacillus thuringiensis) produced bioflocculant optimally when the media had mixed nitrogen sources (Urea, ammonium chloride and tryptone (67%)) and glucose (85.65%) as a sole carbon source, also Ca2+ (74.6%) was the best cation that induced the production of bioflocculant. After purification, the bioflocculant flocculated optimally in alkaline pH 12 (81%) in the presence of Mn2+ (73%) and Ca2+ (72.8%). Chemical analysis of the bioflocculant revealed it to be a polysaccharide. Both bioflocculants flocculate efficiently and can be used to replace synthetic flocculants in water treatment, wastewater, in downstream processing, and processing of food and chemicals and other industrial uses of flocculants. Challenges though (i) are to develop conditions for large scale production of the bioflocculant, (ii) to do further characterization of the both bioflocculants (iii) to assess the bioflocculants for treatments of water/wastewater, and to apply it in various industrial processes.
- Full Text:
- Date Issued: 2015
- Authors: Ntozonke, Ncedo
- Date: 2015
- Language: English
- Type: Thesis , Masters , MSc (Microbiology)
- Identifier: vital:11298 , http://hdl.handle.net/10353/d1021290
- Description: Bioflocculants are polymers, mostly, of microbial origin which floc out suspended particles from liquid medium. The ability of these biopolymers to remove suspended particles from solutions is termed bioflocculation, and the efficiency of flocculation activities depends on the characteristics of the flocculants. In comparison with conventionally used flocculants, bioflocculants have the advantage of being safe (no toxic effects known), biodegradable and harmlessness to the environment. The study assessed production of bioflocculant by two marine bacteria from the bottom sediment of marine environment. The 16S rDNA was used for identification, and the two bacteria species were identified as Enterococcus hirae and Bacillus thuringiensis. Factors affecting the production and activity of the bioflocculants produced by these two organisms were studied. The bacteria optimally produced bioflocculant with fructose (91.7%) and urea (91%) as sole carbon and nitrogen sources respectively. Mg2+ (87%) and Ca2+ (86%), likewise, served as best cation sources on the production of the bioflocculant at pH 5(93%). Additionally, the flocculating activity of the bioflocculant increased with the addition of Mg2+ (81%) and Na+ (81%), and the highest flocculating activity was at pH 5 of the kaolin clay. The Fourier transform infrared spectroscopy (FTIR) shows that the bioflocculant is a glycoprotein. The second bacterium (Bacillus thuringiensis) produced bioflocculant optimally when the media had mixed nitrogen sources (Urea, ammonium chloride and tryptone (67%)) and glucose (85.65%) as a sole carbon source, also Ca2+ (74.6%) was the best cation that induced the production of bioflocculant. After purification, the bioflocculant flocculated optimally in alkaline pH 12 (81%) in the presence of Mn2+ (73%) and Ca2+ (72.8%). Chemical analysis of the bioflocculant revealed it to be a polysaccharide. Both bioflocculants flocculate efficiently and can be used to replace synthetic flocculants in water treatment, wastewater, in downstream processing, and processing of food and chemicals and other industrial uses of flocculants. Challenges though (i) are to develop conditions for large scale production of the bioflocculant, (ii) to do further characterization of the both bioflocculants (iii) to assess the bioflocculants for treatments of water/wastewater, and to apply it in various industrial processes.
- Full Text:
- Date Issued: 2015
Assessment of the effects of stream channel incision on soil water levels, soil morphology and vegetation in a wetland in the Hogsback area, Eastern Cape, South Africa
- Authors: Omar, Mohamed Yussuf
- Date: 2015
- Subjects: Hydrology Wetland Soil Formation
- Language: English
- Type: Thesis , Masters , Degree
- Identifier: http://hdl.handle.net/10353/3132 , vital:28264
- Description: Wetland degradation in the form of channel incisioning can significantly alter the hydrological functioning of a wetland. In this study in a small headwater wetland in the Hogsback area, Eastern Cape Province, the impact of channel incisioning on soil water levels and soil morphology was examined. A good correlation (R2 = 0.89) exists between the depth of channel incisioning and average water table depths in most of the 21 installed piezometers. In localised cases the upslope supply of water was in equilibrium with drainage from the piezometers. Although all the studied soils show hydromorphic characteristics, those continuously saturated close to the surface exhibit redox accumulations in oxygen supplying macropores, whereas gleyic colour patterns occur deeper in soils where the water table has been lowered by channel incision. The nature and occurrence of different hydromorphic soil indicators observed confirm the contribution of soil morphology as a valuable indicator of long-term average soil water conditions. The study evaluates the effects of hydrological processes on plant species composition and distribution in a Hogsback wetland. Twenty-four circular plots with a radius of 2 m were established between March and August 2013. Within each sample plot, the habitat information and species present were recorded including Braun-Blanquet cover-abundance value for each and every species present in the plot. Plant species were identified in the field and the unknown plant species were collected, pressed, oven-dried and identified at the National Herbarium, South African Biodiversity Institute (SANBI), Pretoria and Schonland Herbarium, Rhodes University, Grahamstown. A total of 39 taxa belonging to 19 families and 34 genera were recorded from the Hogsback wetland. Of the documented taxa, three were exotic and three endemic to South Africa, indicating diversity and dynamic nature of Hogsback wetland flora. Plant families with the highest number of species were: Poaceae (11 species), Asteraceae (5 species), Onagraceae and Cyperaceae with 3 taxa each. The low number of exotic plant species in Hogsback wetland (three taxa in total) indicates limited anthropogenic influence. Unique species recorded in Hogsback wetlands are three species that are endemic to South Africa, namely, Alchemilla capensis, Helichrysum rosum and Lysimachia nutans. Five main floristic associations were identified from the Hierarchical Cluster Analysis whilst Detrenched .Correspondence Analysis (DCA) identified four groups. The Canonical Correspondence Analysis (CCA) indicates that edaphic factors, particularly in an area covered with water, erosion category, organic matter content and water table depth were the most important environmental variables measured accounting for the vegetation pattern present in the Hogsback wetland.
- Full Text:
- Date Issued: 2015
- Authors: Omar, Mohamed Yussuf
- Date: 2015
- Subjects: Hydrology Wetland Soil Formation
- Language: English
- Type: Thesis , Masters , Degree
- Identifier: http://hdl.handle.net/10353/3132 , vital:28264
- Description: Wetland degradation in the form of channel incisioning can significantly alter the hydrological functioning of a wetland. In this study in a small headwater wetland in the Hogsback area, Eastern Cape Province, the impact of channel incisioning on soil water levels and soil morphology was examined. A good correlation (R2 = 0.89) exists between the depth of channel incisioning and average water table depths in most of the 21 installed piezometers. In localised cases the upslope supply of water was in equilibrium with drainage from the piezometers. Although all the studied soils show hydromorphic characteristics, those continuously saturated close to the surface exhibit redox accumulations in oxygen supplying macropores, whereas gleyic colour patterns occur deeper in soils where the water table has been lowered by channel incision. The nature and occurrence of different hydromorphic soil indicators observed confirm the contribution of soil morphology as a valuable indicator of long-term average soil water conditions. The study evaluates the effects of hydrological processes on plant species composition and distribution in a Hogsback wetland. Twenty-four circular plots with a radius of 2 m were established between March and August 2013. Within each sample plot, the habitat information and species present were recorded including Braun-Blanquet cover-abundance value for each and every species present in the plot. Plant species were identified in the field and the unknown plant species were collected, pressed, oven-dried and identified at the National Herbarium, South African Biodiversity Institute (SANBI), Pretoria and Schonland Herbarium, Rhodes University, Grahamstown. A total of 39 taxa belonging to 19 families and 34 genera were recorded from the Hogsback wetland. Of the documented taxa, three were exotic and three endemic to South Africa, indicating diversity and dynamic nature of Hogsback wetland flora. Plant families with the highest number of species were: Poaceae (11 species), Asteraceae (5 species), Onagraceae and Cyperaceae with 3 taxa each. The low number of exotic plant species in Hogsback wetland (three taxa in total) indicates limited anthropogenic influence. Unique species recorded in Hogsback wetlands are three species that are endemic to South Africa, namely, Alchemilla capensis, Helichrysum rosum and Lysimachia nutans. Five main floristic associations were identified from the Hierarchical Cluster Analysis whilst Detrenched .Correspondence Analysis (DCA) identified four groups. The Canonical Correspondence Analysis (CCA) indicates that edaphic factors, particularly in an area covered with water, erosion category, organic matter content and water table depth were the most important environmental variables measured accounting for the vegetation pattern present in the Hogsback wetland.
- Full Text:
- Date Issued: 2015
Characterization of some virulence and antibiotic resistance genes of Staphylococcus aureus isolated from cases of Bovine Mastitis in Nkonkobe Municipality, Eastern Cape Province, RSA
- Authors: Pekana, Abongile
- Date: 2015
- Language: English
- Type: Thesis , Masters , MSc (Microbiology)
- Identifier: vital:11293 , http://hdl.handle.net/10353/d1021133
- Description: Staphylococcus aureus is one of the predominant causative agents of mastitis disease in dairy herds. Mastitis disease has a negative impact in the economic losses in the dairy sector across the globe. The aim of this study is to detect some of the virulence genes in the S. aureus isolated from 400 milk samples of subclinical and clinical mastitis dairy cows in Fort Hare dairy farm and Middle Drift dairy farm in Alice in the Eastern Cape province of South Africa. In addition antibiotic resistance pattern and antibiotic resistance genes were investigated. Gram-staining, oxidase test, catalase test and API Staph kit were preliminary biochemical tests used for the identification of S. aureus isolates. The MALDI-TOF-MS was also used for further identification. Polymerase chain reaction was performed of genes encoding antibiotic resistance as well as clumping (clfA), coagulase (coa) gene, toxic shock syndrome (tsst), exfoliative toxin A and B (eta and etb), and the gene segment encoding the immunoglobulin G binding region and X region of protein gene spa. A total of 20 (5%) S. aureus strains obtained from 400 milk samples from the two farms were subjected to 16 antibiotics for antibiotic susceptibility testing. In Middle Drift dairy farm 11 (5.5%) isolates were obtained from 200 samples and 9 (4.5%) isolates were obtained in Fort Hare dairy farm from 200 samples. A large percent of the isolates were resistant to penicillin G (60%), followed by trimethoprim (60%) and tetracycline (60%), trimethoprim-sulfamethaxazole (55%), telithroprim (55%) and doxycycline (45%). Most of the isolates were sensitive to several (50-85%) antibiotics. Of the twenty isolates tested 12 samples contained the penicillin antibiotic resistance gene (blaZ gene), 8 samples contained at least one aminoglycoside-modifying enzyme gene (AME gene); the (aac(6’)/aph(2’’) gene and no amplification occurred for aph(3’)-IIIa and ant(4’)-Ia) genes. In the case of the tetracycline antibiotic resistance gene (tetK and tetM), 2 samples contained tetM and a single sample contained tetK gene. No amplification was observed for the erythromycin antibiotic resistance genes (ermA, ermB, ermC, Mef and msrA). All the samples tested were negative for the expression of toxic syndrome gene (tsst), etb, and Immunoglobulin G binding region. However, amplification of the clumping factor was observed in 7 (35%) isolates of S. aureus, exfoliative toxin (eta) expressed 4(20%) isolates; coagulase gene (coa) yielded six DNA bands of six differences sizes from 16 (80%) isolates. A total of four different bands size were expressed for the spa X region from 12 (60%) isolates. The data obtained in this study suggests that poor hygienic practices and inadequate management practices are responsible for the increase in Staphylococcus aureus isolation. The high resistance of S. aureus to antibiotics and the distribution of virulence genes contribute in bovine mastitis in these farms may cause health problems in the community consuming raw milk purchased from these farms.
- Full Text:
- Date Issued: 2015
- Authors: Pekana, Abongile
- Date: 2015
- Language: English
- Type: Thesis , Masters , MSc (Microbiology)
- Identifier: vital:11293 , http://hdl.handle.net/10353/d1021133
- Description: Staphylococcus aureus is one of the predominant causative agents of mastitis disease in dairy herds. Mastitis disease has a negative impact in the economic losses in the dairy sector across the globe. The aim of this study is to detect some of the virulence genes in the S. aureus isolated from 400 milk samples of subclinical and clinical mastitis dairy cows in Fort Hare dairy farm and Middle Drift dairy farm in Alice in the Eastern Cape province of South Africa. In addition antibiotic resistance pattern and antibiotic resistance genes were investigated. Gram-staining, oxidase test, catalase test and API Staph kit were preliminary biochemical tests used for the identification of S. aureus isolates. The MALDI-TOF-MS was also used for further identification. Polymerase chain reaction was performed of genes encoding antibiotic resistance as well as clumping (clfA), coagulase (coa) gene, toxic shock syndrome (tsst), exfoliative toxin A and B (eta and etb), and the gene segment encoding the immunoglobulin G binding region and X region of protein gene spa. A total of 20 (5%) S. aureus strains obtained from 400 milk samples from the two farms were subjected to 16 antibiotics for antibiotic susceptibility testing. In Middle Drift dairy farm 11 (5.5%) isolates were obtained from 200 samples and 9 (4.5%) isolates were obtained in Fort Hare dairy farm from 200 samples. A large percent of the isolates were resistant to penicillin G (60%), followed by trimethoprim (60%) and tetracycline (60%), trimethoprim-sulfamethaxazole (55%), telithroprim (55%) and doxycycline (45%). Most of the isolates were sensitive to several (50-85%) antibiotics. Of the twenty isolates tested 12 samples contained the penicillin antibiotic resistance gene (blaZ gene), 8 samples contained at least one aminoglycoside-modifying enzyme gene (AME gene); the (aac(6’)/aph(2’’) gene and no amplification occurred for aph(3’)-IIIa and ant(4’)-Ia) genes. In the case of the tetracycline antibiotic resistance gene (tetK and tetM), 2 samples contained tetM and a single sample contained tetK gene. No amplification was observed for the erythromycin antibiotic resistance genes (ermA, ermB, ermC, Mef and msrA). All the samples tested were negative for the expression of toxic syndrome gene (tsst), etb, and Immunoglobulin G binding region. However, amplification of the clumping factor was observed in 7 (35%) isolates of S. aureus, exfoliative toxin (eta) expressed 4(20%) isolates; coagulase gene (coa) yielded six DNA bands of six differences sizes from 16 (80%) isolates. A total of four different bands size were expressed for the spa X region from 12 (60%) isolates. The data obtained in this study suggests that poor hygienic practices and inadequate management practices are responsible for the increase in Staphylococcus aureus isolation. The high resistance of S. aureus to antibiotics and the distribution of virulence genes contribute in bovine mastitis in these farms may cause health problems in the community consuming raw milk purchased from these farms.
- Full Text:
- Date Issued: 2015
Chemical constituents and biological studies of Tagetes minuta L. and Rauvolfia caffra Sond
- Authors: Mlala, Sithenkosi
- Date: 2015
- Language: English
- Type: Thesis , Masters , MSc (Organic Chemistry)
- Identifier: vital:11358 , http://hdl.handle.net/10353/d1021325
- Description: Consequently, specific parts or the whole plant can be used for various treatments. The aim of this study was to extract, isolate and characterize the biologically active volatile and non-volatile compounds from Tagetes minuta and Rauvolfia caffra respectively. Tagetes minuta plant was considered for extraction of essential oils using hydrodistillation method. Cis-β-ocimene (38.03%), caryophyllene oxide (18.04%), alloocimene (25.35 %), isopropyl tetradecanoate (17.02 %), cis-ocimene (38.14%) and trans-β-ocimene (37.03%) were the major components of essential oil analyzed from fresh stem, dried stem, fresh leaf, dried leaf, fresh flower and dried flower respectively. The volatile compounds were identified by Gas Chromatography-Mass Spectrometry (GC-MS) and Gas Chromatography (GC). Essential oil of dried stem leaf and flower parts of T. minuta exhibit antioxidant activity as demonstrated by the DPPH and FRAP bioassays. Crude extracts were extracted from R. caffra stem bark using sequence of solvents namely n-hexane, dichloromethane, ethyl acetate, methanol and ethanol. A white powder, a β-sitosterol (non-volatile compound) was isolated by column chromatography from ethyl acetate fractions of R. caffra stem bark and identified on various spectroscopic techniques such as FTIR and (1D and 2D) NMR. Melting point was also determined to be a sharp 129-130 ºC. DCM, EA, MetOH and EtOH fractions as well as β-Sitosterol (compound SM/01), showed antioxidant activity when tested on DPPH, FRAP, total phenolic and flavonoid bioassays. This antioxidant activity might be due to the presence of hydroxyl groups in the compound and crude fractions. On the other hand, T. minuta’s essential oil showed high antioxidant activity when evaluated on the DPPH and FRAP bioassays, which can be attributed to the presence of oxygenated monoterpenes and sesquiterpenes known to act as free radical scavenging and reducing agents. The use of R. caffra stem bark extracts against hypertension and other diseases by traditional healers could be attributed to the presence of phytochemicals (polyphenols and flavonoids) with known health benefits. Thus, it is recommended that the plant should be exploited further using modern techniques involving separation and purification of compounds that can be used for drug formulation. This study supports the use of T. minuta and R. caffra as the potential natural antioxidant source to manage various diseases including hypertension.
- Full Text:
- Date Issued: 2015
- Authors: Mlala, Sithenkosi
- Date: 2015
- Language: English
- Type: Thesis , Masters , MSc (Organic Chemistry)
- Identifier: vital:11358 , http://hdl.handle.net/10353/d1021325
- Description: Consequently, specific parts or the whole plant can be used for various treatments. The aim of this study was to extract, isolate and characterize the biologically active volatile and non-volatile compounds from Tagetes minuta and Rauvolfia caffra respectively. Tagetes minuta plant was considered for extraction of essential oils using hydrodistillation method. Cis-β-ocimene (38.03%), caryophyllene oxide (18.04%), alloocimene (25.35 %), isopropyl tetradecanoate (17.02 %), cis-ocimene (38.14%) and trans-β-ocimene (37.03%) were the major components of essential oil analyzed from fresh stem, dried stem, fresh leaf, dried leaf, fresh flower and dried flower respectively. The volatile compounds were identified by Gas Chromatography-Mass Spectrometry (GC-MS) and Gas Chromatography (GC). Essential oil of dried stem leaf and flower parts of T. minuta exhibit antioxidant activity as demonstrated by the DPPH and FRAP bioassays. Crude extracts were extracted from R. caffra stem bark using sequence of solvents namely n-hexane, dichloromethane, ethyl acetate, methanol and ethanol. A white powder, a β-sitosterol (non-volatile compound) was isolated by column chromatography from ethyl acetate fractions of R. caffra stem bark and identified on various spectroscopic techniques such as FTIR and (1D and 2D) NMR. Melting point was also determined to be a sharp 129-130 ºC. DCM, EA, MetOH and EtOH fractions as well as β-Sitosterol (compound SM/01), showed antioxidant activity when tested on DPPH, FRAP, total phenolic and flavonoid bioassays. This antioxidant activity might be due to the presence of hydroxyl groups in the compound and crude fractions. On the other hand, T. minuta’s essential oil showed high antioxidant activity when evaluated on the DPPH and FRAP bioassays, which can be attributed to the presence of oxygenated monoterpenes and sesquiterpenes known to act as free radical scavenging and reducing agents. The use of R. caffra stem bark extracts against hypertension and other diseases by traditional healers could be attributed to the presence of phytochemicals (polyphenols and flavonoids) with known health benefits. Thus, it is recommended that the plant should be exploited further using modern techniques involving separation and purification of compounds that can be used for drug formulation. This study supports the use of T. minuta and R. caffra as the potential natural antioxidant source to manage various diseases including hypertension.
- Full Text:
- Date Issued: 2015
Consumer perceptions and values on beef quality: implications on beef markets
- Authors: Mabhera, Sunungukai.
- Date: 2015
- Subjects: Beef -- Quality -- Health aspects -- South Africa -- Eastern Cape , Livestock -- Handling -- South Africa -- Eastern Cape , Beef cattle -- Breeding -- South Africa -- Eastern Cape , Beef -- Quality -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc Agric (Agricultural Economics)
- Identifier: vital:11224 , http://hdl.handle.net/10353/d1020173 , Beef -- Quality -- Health aspects -- South Africa -- Eastern Cape , Livestock -- Handling -- South Africa -- Eastern Cape , Beef cattle -- Breeding -- South Africa -- Eastern Cape , Beef -- Quality -- South Africa -- Eastern Cape
- Description: Beef constitutes an important part of many consumers’ diets. Beef is the most consumed red meat in South Africa. Consumer perceptions can affect the whole supply or value chain of beef. Recently there has been increased interest in food safety; greater concern for environmental and animal welfare issues, increased importance of eating quality and healthy food as well as the greater role of food services. The demand for beef is no longer limited to economic factors alone but to non-economic factors as well. Consumers of beef in Alice have become more concerned about meat-borne risks and personal health. This research prioritized the exploration of the beef consumers’ (i) self-perception (ii) price perception (iii) benefit perception [in the form of – (a) value perception and (b) quality perception]. The study was conducted in the Eastern Cape Province specifically in Alice town and the surrounding rural areas (Ntselamanzi, Gaga, Hillcrest, Gqumashe, and Dyamala) of the Nkonkobe municipality. Anyone who admitted to eating beef and at the point of data collection bought beef for their own consumption or family consumption was deemed as a unit of analysis. Non – probabilistic sampling techniques which included accidental and random sampling were used to collect data from 100 interviewees. A semi structured questionnaire was used to analyse the perceptions and attitudes of beef consumers. The respondents were asked to indicate their agreement or disagreement with 47 statements or items presented on either five alternatives in a Likert scale scored from 1 (strongly disagree) to 5 (strongly agree) or a six Likert scale ranging from 1 (very low) through 5 (very high) to 6 (I do not know).The data was analysed using SPSS. It was discovered that beef consumers did not consider either intrinsic or extrinsic cues in isolation when purchasing beef but rather all characteristics contribute to the final perception. The Alice consumer market is heterogeneous and consists of different races with different cultures and market segments with varying needs and preferences. The results showed that five factors were extracted from forty seven items Factor 1: Information reliance and quality indication; Factor 2: convenience; Factor 3: Traceability and animal Welfare; Factor 4: Health and safety Conscious and Factor 5: Price and Branding. Furthermore, four main consumer segments emerged as - Segment 1: Informed buyers; Segment 2: Elite buyers; Segment 3: Health & safety conscious buyers and Segment 4: Apathetic buyers. The cluster analysis shows that quality is a subjective concept that is informed by a consumer’s personal taste and preferences. Taste and preferences inform the consumer’s effective demand which in retrospect is informed by the consumer’s socioeconomic status.
- Full Text:
- Date Issued: 2015
- Authors: Mabhera, Sunungukai.
- Date: 2015
- Subjects: Beef -- Quality -- Health aspects -- South Africa -- Eastern Cape , Livestock -- Handling -- South Africa -- Eastern Cape , Beef cattle -- Breeding -- South Africa -- Eastern Cape , Beef -- Quality -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc Agric (Agricultural Economics)
- Identifier: vital:11224 , http://hdl.handle.net/10353/d1020173 , Beef -- Quality -- Health aspects -- South Africa -- Eastern Cape , Livestock -- Handling -- South Africa -- Eastern Cape , Beef cattle -- Breeding -- South Africa -- Eastern Cape , Beef -- Quality -- South Africa -- Eastern Cape
- Description: Beef constitutes an important part of many consumers’ diets. Beef is the most consumed red meat in South Africa. Consumer perceptions can affect the whole supply or value chain of beef. Recently there has been increased interest in food safety; greater concern for environmental and animal welfare issues, increased importance of eating quality and healthy food as well as the greater role of food services. The demand for beef is no longer limited to economic factors alone but to non-economic factors as well. Consumers of beef in Alice have become more concerned about meat-borne risks and personal health. This research prioritized the exploration of the beef consumers’ (i) self-perception (ii) price perception (iii) benefit perception [in the form of – (a) value perception and (b) quality perception]. The study was conducted in the Eastern Cape Province specifically in Alice town and the surrounding rural areas (Ntselamanzi, Gaga, Hillcrest, Gqumashe, and Dyamala) of the Nkonkobe municipality. Anyone who admitted to eating beef and at the point of data collection bought beef for their own consumption or family consumption was deemed as a unit of analysis. Non – probabilistic sampling techniques which included accidental and random sampling were used to collect data from 100 interviewees. A semi structured questionnaire was used to analyse the perceptions and attitudes of beef consumers. The respondents were asked to indicate their agreement or disagreement with 47 statements or items presented on either five alternatives in a Likert scale scored from 1 (strongly disagree) to 5 (strongly agree) or a six Likert scale ranging from 1 (very low) through 5 (very high) to 6 (I do not know).The data was analysed using SPSS. It was discovered that beef consumers did not consider either intrinsic or extrinsic cues in isolation when purchasing beef but rather all characteristics contribute to the final perception. The Alice consumer market is heterogeneous and consists of different races with different cultures and market segments with varying needs and preferences. The results showed that five factors were extracted from forty seven items Factor 1: Information reliance and quality indication; Factor 2: convenience; Factor 3: Traceability and animal Welfare; Factor 4: Health and safety Conscious and Factor 5: Price and Branding. Furthermore, four main consumer segments emerged as - Segment 1: Informed buyers; Segment 2: Elite buyers; Segment 3: Health & safety conscious buyers and Segment 4: Apathetic buyers. The cluster analysis shows that quality is a subjective concept that is informed by a consumer’s personal taste and preferences. Taste and preferences inform the consumer’s effective demand which in retrospect is informed by the consumer’s socioeconomic status.
- Full Text:
- Date Issued: 2015
Creating a safe learning environment in two schools in the Butterworth District, Eastern Cape
- Authors: Vokozela, Zandile
- Date: 2015
- Language: English
- Type: Thesis , Masters , Msc (Environmental Studies)
- Identifier: vital:11881 , http://hdl.handle.net/10353/d1021297
- Description: This study focuses on the creation of a safe learning environment at two schools in the Butterworth District of the Eastern Cape in South Africa. The two schools are Ndabankulu Senior Secondary School and Butterworth High School. The study is of a comparative design and aims to assist the communities of Ndabankulu Senior Secondary School, and Butterworth High School to improve health, safety and security issues of their children by reducing their exposure to environmental risks while attending school. An ethnographic study was used to collect data and the study employed questionnaires, document analysis and interviews as methods of collecting data. The primary aim of this study was to assess whether the school is still a safe place for learning and teaching to take place without fear and harm so that both learners and teachers can attain growth and development. Physical risks were assessed through observation and document analysis. Interviews were conducted with the senior members of staff while questionnaires were issued to eighty learners and were all returned back for analysis. The content analysis and interpretation yielded findings that suggests that hazards that may harm the development of learners at Ndabankulu S.S.S. and Butterworth High school exist. The study concludes that it is crucial that strategies and necessary interventions be set up and implemented to ensure that all stakeholders perceive school safety as an important aspect, both for the benefit of the school and that of the wider society. The barriers to school safety, specifically to both schools in this study need to be attended to. The study has presented findings that are consistent with those of other studies which emphasized that if barriers to school safety are identified, confronted and tackled, the schools could benefit positively from effects of involving everyone to create a safe learning environment. The conditions under which learners receive education in South Africa have to be closely and constantly monitored by Departmental officials. Teachers and managers need to be trained in their duties so that schools become places where learners are safe and enjoy reaching their future goals.
- Full Text:
- Date Issued: 2015
- Authors: Vokozela, Zandile
- Date: 2015
- Language: English
- Type: Thesis , Masters , Msc (Environmental Studies)
- Identifier: vital:11881 , http://hdl.handle.net/10353/d1021297
- Description: This study focuses on the creation of a safe learning environment at two schools in the Butterworth District of the Eastern Cape in South Africa. The two schools are Ndabankulu Senior Secondary School and Butterworth High School. The study is of a comparative design and aims to assist the communities of Ndabankulu Senior Secondary School, and Butterworth High School to improve health, safety and security issues of their children by reducing their exposure to environmental risks while attending school. An ethnographic study was used to collect data and the study employed questionnaires, document analysis and interviews as methods of collecting data. The primary aim of this study was to assess whether the school is still a safe place for learning and teaching to take place without fear and harm so that both learners and teachers can attain growth and development. Physical risks were assessed through observation and document analysis. Interviews were conducted with the senior members of staff while questionnaires were issued to eighty learners and were all returned back for analysis. The content analysis and interpretation yielded findings that suggests that hazards that may harm the development of learners at Ndabankulu S.S.S. and Butterworth High school exist. The study concludes that it is crucial that strategies and necessary interventions be set up and implemented to ensure that all stakeholders perceive school safety as an important aspect, both for the benefit of the school and that of the wider society. The barriers to school safety, specifically to both schools in this study need to be attended to. The study has presented findings that are consistent with those of other studies which emphasized that if barriers to school safety are identified, confronted and tackled, the schools could benefit positively from effects of involving everyone to create a safe learning environment. The conditions under which learners receive education in South Africa have to be closely and constantly monitored by Departmental officials. Teachers and managers need to be trained in their duties so that schools become places where learners are safe and enjoy reaching their future goals.
- Full Text:
- Date Issued: 2015
Determination and validation of medicinal plants used by farmers to control internal and external parasites in goats in the Eastern Cape Province, South Africa
- Authors: Sanhokwe, Marcia
- Date: 2015
- Subjects: Medicinal plants -- South Africa -- Eastern Cape Goats -- Parasites -- Control
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/2249 , vital:27718
- Description: The broad objective of the study was to determine and validate medicinal plants used by resource-limited farmers to control internal and external parasites in goats in the Eastern Cape Province, South Africa. A survey was conducted among 50 farmers and three herbalists to determine medicinal plants used to control parasites in goats. The survey revealed nine plant species belonging to eight families that were used. Among the identified plant species, Aloe ferox, Acokanthera oppositifolia and Elephantorrhiza elephantina were the plants having the highest Fidelity Level for their use, each scored 100.00 percent, followed by Albuca setosa (83.33 percent). These plants were then selected for validation studies. Gas-Chromatography-Mass-Spectrometry (GC-MS) revealed 7, 33, 26 and 32 bioactive phytochemicals in A. ferox, E. elephantina, A. oppositifolia and A. setosa, respectively. Terpenes and fatty acids were present, oxygenated terpenes being the most abundant hydrocarbons present in all the four plant species. The effect of acetone, methanol and ethanol extracts of leaves of Aloe ferox and Acokanthera oppositifolia on tick repellency and acaricidal activity were investigated on blood engorged Ambylomma hebraeum and Rhipicephalus decoloratus ticks at concentration 15, 30 and 50 percent. The 30 and 50 percent acetone extract of A. ferox and Dazzel dip had the highest acaricidal properties of 100 percent. The 50 percent methanol extract of A. oppositifolia and 50 percent acetone extract of A. ferox had the highest repellency activity of 89 percent and 85.33 percent, respectively. Results from this study revealed that the efficacy of medicinal plants used by farmers to control ticks vary with the type of solvent used for extracting the bioactive compounds. Furthermore, it revealed that Aloe ferox and A. opppositifolia plant extracts possess repellent and acaricidal activities. In a study to investigate the anthelminthic effect of crude extracts of Elephantorrhiza elephantina and Albuca setosa plants, significant anthelminthic effect on nematodes was observed in both plants. In this study, all E. elephantina and A. setosa extracts caused paralysis and mortality. Methanol was the most effective solvent in extracting bioactive compounds and methanol extract showed the best anthelminthic effects among the crude extracts investigated in both plants. The least time taken for the worms to be paralysed was 8.33 mins and 14.33mins in 100mg/ml methanol extracts of E. elephantina and A. setosa, resepectively. Methanol extract of E. elephantina and A. setosa (100mg/ml) had the highest anthelminthic activity and mortality was recorded after 18mins and 20mins, respectively. Results from this study revealed that these two plants possess anthelminthic activities. The study revealed that resource-limited farmers use medicinal plants to control internal and external parasites in goats. Gas-Chromatography-Mass-Spectrometry analysis showed that these plants contain bioactive compounds that have a potential in controlling parasites. Validation studies showed that A. ferox and A. oppositifolia possess repellent and acaricidal activities whereas A. setosa and E. elephantina possess anthelminthic activities.
- Full Text:
- Date Issued: 2015
- Authors: Sanhokwe, Marcia
- Date: 2015
- Subjects: Medicinal plants -- South Africa -- Eastern Cape Goats -- Parasites -- Control
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/2249 , vital:27718
- Description: The broad objective of the study was to determine and validate medicinal plants used by resource-limited farmers to control internal and external parasites in goats in the Eastern Cape Province, South Africa. A survey was conducted among 50 farmers and three herbalists to determine medicinal plants used to control parasites in goats. The survey revealed nine plant species belonging to eight families that were used. Among the identified plant species, Aloe ferox, Acokanthera oppositifolia and Elephantorrhiza elephantina were the plants having the highest Fidelity Level for their use, each scored 100.00 percent, followed by Albuca setosa (83.33 percent). These plants were then selected for validation studies. Gas-Chromatography-Mass-Spectrometry (GC-MS) revealed 7, 33, 26 and 32 bioactive phytochemicals in A. ferox, E. elephantina, A. oppositifolia and A. setosa, respectively. Terpenes and fatty acids were present, oxygenated terpenes being the most abundant hydrocarbons present in all the four plant species. The effect of acetone, methanol and ethanol extracts of leaves of Aloe ferox and Acokanthera oppositifolia on tick repellency and acaricidal activity were investigated on blood engorged Ambylomma hebraeum and Rhipicephalus decoloratus ticks at concentration 15, 30 and 50 percent. The 30 and 50 percent acetone extract of A. ferox and Dazzel dip had the highest acaricidal properties of 100 percent. The 50 percent methanol extract of A. oppositifolia and 50 percent acetone extract of A. ferox had the highest repellency activity of 89 percent and 85.33 percent, respectively. Results from this study revealed that the efficacy of medicinal plants used by farmers to control ticks vary with the type of solvent used for extracting the bioactive compounds. Furthermore, it revealed that Aloe ferox and A. opppositifolia plant extracts possess repellent and acaricidal activities. In a study to investigate the anthelminthic effect of crude extracts of Elephantorrhiza elephantina and Albuca setosa plants, significant anthelminthic effect on nematodes was observed in both plants. In this study, all E. elephantina and A. setosa extracts caused paralysis and mortality. Methanol was the most effective solvent in extracting bioactive compounds and methanol extract showed the best anthelminthic effects among the crude extracts investigated in both plants. The least time taken for the worms to be paralysed was 8.33 mins and 14.33mins in 100mg/ml methanol extracts of E. elephantina and A. setosa, resepectively. Methanol extract of E. elephantina and A. setosa (100mg/ml) had the highest anthelminthic activity and mortality was recorded after 18mins and 20mins, respectively. Results from this study revealed that these two plants possess anthelminthic activities. The study revealed that resource-limited farmers use medicinal plants to control internal and external parasites in goats. Gas-Chromatography-Mass-Spectrometry analysis showed that these plants contain bioactive compounds that have a potential in controlling parasites. Validation studies showed that A. ferox and A. oppositifolia possess repellent and acaricidal activities whereas A. setosa and E. elephantina possess anthelminthic activities.
- Full Text:
- Date Issued: 2015
Development of high performance computing cluster for evaluation of sequence alignment algorithms
- Authors: Ngxande, Mkhuseli
- Date: 2015
- Language: English
- Type: Thesis , Masters , MSc (Computer Science)
- Identifier: vital:11399 , http://hdl.handle.net/10353/d1020163
- Description: As the biological databases are increasing rapidly, there is a challenge for both Biologists and Computer Scientists to develop algorithms and databases to manage the increasing data. There are many algorithms developed to align the sequences stored in biological databases - some take time to process the data while others are inefficient to produce reasonable results. As more data is generated, and time consuming algorithms are developed to handle them, there is a need for specialized computers to handle the computations. Researchers are typically limited by the computational power of their computers. High Performance Computing (HPC) field addresses this challenge and can be used in a cost-effective manner where there is no need for expensive equipment, instead old computers can be used together to form a powerful system. This is the premise of this research, wherein the setup of a low-cost Beowulf cluster is explored, with the subsequent evaluation of its performance for processing sequent alignment algorithms. A mixed method methodology is used in this dissertation, which consists of literature study, theoretical and practise based system. This mixed method methodology also have a proof and concept where the Beowulf cluster is designed and implemented to perform the sequence alignment algorithms and also the performance test. This dissertation firstly gives an overview of sequence alignment algorithms that are already developed and also highlights their timeline. A presentation of the design and implementation of the Beowulf Cluster is highlighted and this is followed by the experiments on the baseline performance of the cluster. A detailed timeline of the sequence alignment algorithms is given and also the comparison between ClustalW-MPI and T-Coffee (Tree-based Consistency Objective Function For alignment Evaluation) algorithm is presented as part of the findings in the research study. The efficiency of the cluster was observed to be 19.8%, this percentage is unexpected because the predicted efficiency is 83.3%, which is found in the theoretical cluster calculator. The theoretical performance of the cluster showed a high performance as compared with the experimental performance, this is attributable to the slow network, which was 100Mbps, low processor speed of 2.50 GHz, and low memory of 2 Gigabytes.
- Full Text:
- Date Issued: 2015
- Authors: Ngxande, Mkhuseli
- Date: 2015
- Language: English
- Type: Thesis , Masters , MSc (Computer Science)
- Identifier: vital:11399 , http://hdl.handle.net/10353/d1020163
- Description: As the biological databases are increasing rapidly, there is a challenge for both Biologists and Computer Scientists to develop algorithms and databases to manage the increasing data. There are many algorithms developed to align the sequences stored in biological databases - some take time to process the data while others are inefficient to produce reasonable results. As more data is generated, and time consuming algorithms are developed to handle them, there is a need for specialized computers to handle the computations. Researchers are typically limited by the computational power of their computers. High Performance Computing (HPC) field addresses this challenge and can be used in a cost-effective manner where there is no need for expensive equipment, instead old computers can be used together to form a powerful system. This is the premise of this research, wherein the setup of a low-cost Beowulf cluster is explored, with the subsequent evaluation of its performance for processing sequent alignment algorithms. A mixed method methodology is used in this dissertation, which consists of literature study, theoretical and practise based system. This mixed method methodology also have a proof and concept where the Beowulf cluster is designed and implemented to perform the sequence alignment algorithms and also the performance test. This dissertation firstly gives an overview of sequence alignment algorithms that are already developed and also highlights their timeline. A presentation of the design and implementation of the Beowulf Cluster is highlighted and this is followed by the experiments on the baseline performance of the cluster. A detailed timeline of the sequence alignment algorithms is given and also the comparison between ClustalW-MPI and T-Coffee (Tree-based Consistency Objective Function For alignment Evaluation) algorithm is presented as part of the findings in the research study. The efficiency of the cluster was observed to be 19.8%, this percentage is unexpected because the predicted efficiency is 83.3%, which is found in the theoretical cluster calculator. The theoretical performance of the cluster showed a high performance as compared with the experimental performance, this is attributable to the slow network, which was 100Mbps, low processor speed of 2.50 GHz, and low memory of 2 Gigabytes.
- Full Text:
- Date Issued: 2015
Effect of Tenebrio molitor larvae as a protein source on growth performance, carcass yield and meat quality of broiler chickens
- Authors: Mngqi, Sinethemba Census
- Date: 2015
- Subjects: Broilers (Chickens) Chickens -- Feeding and feeds Meat -- Quality
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/2622 , vital:27944
- Description: This study was conducted to assess the effect of including Tenebrio molitor larvae (T. molitor L) as a protein source in different diets on broiler performance, carcass characteristics and meat quality. A total of 144 day-old Cobb-500 chicks were randomly allocated into three treatment groups, each was allocated 16 birds and reared in 9 identical pens. Experimental diets used were as follows: T1 Control (no T. molitor L inclusion); T2 and T3 contained levels of T. molitor L at 5 percent and 10 percent of dry matter (DM) intake, respectively. Body weights (BW), average daily gain (ADG), feed intake (FI), and Feed conversion ratio (FCR) were measured for the 1st experimental chapter. For the second experimental chapter; live weights (LW) of broilers were recorded before slaughter and thereafter carcass weights (CW), meat yield (weights of breast, thigh, drumstick and wing) were recorded. The dressing percentage (DP percent) was also calculated. Breast muscles were sampled for meat pH and colour measurements. The LW of birds from T1 (0 percent T. molitor L) were significantly different (P<0.05) from both T2 (5 percent T. molitor L) and T3 (10 percent T. molitor L) which were similar to each other, with T2 exhibiting the highest live weights (2166g) and the control treatment exhibiting the lowest live weights (2018.3g). In CW, T1 was significantly different (P<0.05) from T2 while it was similar (P>0.05) to T3. The dressing percent of T1 was significantly different (P<0.05) from T2 and T3 which were similar to each other, with T2 having the highest dressing percentage (78, 2 percent) and T1 having the lowest DP percent (66 percent). The breasts in T2 were significantly higher and different (P<0.05) from both T1 and T3 which were similar to each other. The drumsticks in T3 were significantly different (P<0.05) from T1 while they were similar to T2 with values with T2 having highest values. After 45 minutes of slaughter, a significant difference (P<0.05) was observed in L⃰ among all treatments. In redness (a⃰), T3 was significantly different from T1 but was similar to T2 and all treatments in this study exhibited a darker red meat, with T3 muscles exhibiting darker red colour than the other treatments. Similar results were observed in yellowness (b⃰), where the breast muscles from T3 were more yellow than the other treatments. After 24 hours of slaughter, T2 L⃰ values were significantly different (P<0.05) from both T1 and T3 which were similar to each other. It was also found that the broiler chickens given diet with no T. molitor L inclusion (T1) had lower values of BW, FI, ADG and FCR throughout the experiment than those that were in T2 and T3 with 5 percent and 10 percent T. molitor L inclusion levels, respectively. However, it was also found that although broilers with 5 percent T. molitor L inclusion (T2) in their diet had high ABW and ADG than the broilers with 10 percent T. molitor L inclusion (T3), the T3 birds compared favourably to T2 birds as they required low feed intake to reach the same slaughter weight due to high FCR. It was, therefore, concluded that T. molitor L meal can be incorporated into the diets of broilers to produce heavy birds either at 5 or 10 percent. However, although 5 percent T. molitor L inclusion yields heavier carcasses, the 10 percent T. molitor L inclusion compared favourably to 5 percent inclusion since it required low feed intake to reach the same slaughter weights and there were slight differences on meat quality attributes between the two treatments.Thus T. molitor L at 10 percent inclusion levels was the best inclusion level to enhance broiler growth performance, carcass yield, meat yield and meat quality.
- Full Text:
- Date Issued: 2015
- Authors: Mngqi, Sinethemba Census
- Date: 2015
- Subjects: Broilers (Chickens) Chickens -- Feeding and feeds Meat -- Quality
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/2622 , vital:27944
- Description: This study was conducted to assess the effect of including Tenebrio molitor larvae (T. molitor L) as a protein source in different diets on broiler performance, carcass characteristics and meat quality. A total of 144 day-old Cobb-500 chicks were randomly allocated into three treatment groups, each was allocated 16 birds and reared in 9 identical pens. Experimental diets used were as follows: T1 Control (no T. molitor L inclusion); T2 and T3 contained levels of T. molitor L at 5 percent and 10 percent of dry matter (DM) intake, respectively. Body weights (BW), average daily gain (ADG), feed intake (FI), and Feed conversion ratio (FCR) were measured for the 1st experimental chapter. For the second experimental chapter; live weights (LW) of broilers were recorded before slaughter and thereafter carcass weights (CW), meat yield (weights of breast, thigh, drumstick and wing) were recorded. The dressing percentage (DP percent) was also calculated. Breast muscles were sampled for meat pH and colour measurements. The LW of birds from T1 (0 percent T. molitor L) were significantly different (P<0.05) from both T2 (5 percent T. molitor L) and T3 (10 percent T. molitor L) which were similar to each other, with T2 exhibiting the highest live weights (2166g) and the control treatment exhibiting the lowest live weights (2018.3g). In CW, T1 was significantly different (P<0.05) from T2 while it was similar (P>0.05) to T3. The dressing percent of T1 was significantly different (P<0.05) from T2 and T3 which were similar to each other, with T2 having the highest dressing percentage (78, 2 percent) and T1 having the lowest DP percent (66 percent). The breasts in T2 were significantly higher and different (P<0.05) from both T1 and T3 which were similar to each other. The drumsticks in T3 were significantly different (P<0.05) from T1 while they were similar to T2 with values with T2 having highest values. After 45 minutes of slaughter, a significant difference (P<0.05) was observed in L⃰ among all treatments. In redness (a⃰), T3 was significantly different from T1 but was similar to T2 and all treatments in this study exhibited a darker red meat, with T3 muscles exhibiting darker red colour than the other treatments. Similar results were observed in yellowness (b⃰), where the breast muscles from T3 were more yellow than the other treatments. After 24 hours of slaughter, T2 L⃰ values were significantly different (P<0.05) from both T1 and T3 which were similar to each other. It was also found that the broiler chickens given diet with no T. molitor L inclusion (T1) had lower values of BW, FI, ADG and FCR throughout the experiment than those that were in T2 and T3 with 5 percent and 10 percent T. molitor L inclusion levels, respectively. However, it was also found that although broilers with 5 percent T. molitor L inclusion (T2) in their diet had high ABW and ADG than the broilers with 10 percent T. molitor L inclusion (T3), the T3 birds compared favourably to T2 birds as they required low feed intake to reach the same slaughter weight due to high FCR. It was, therefore, concluded that T. molitor L meal can be incorporated into the diets of broilers to produce heavy birds either at 5 or 10 percent. However, although 5 percent T. molitor L inclusion yields heavier carcasses, the 10 percent T. molitor L inclusion compared favourably to 5 percent inclusion since it required low feed intake to reach the same slaughter weights and there were slight differences on meat quality attributes between the two treatments.Thus T. molitor L at 10 percent inclusion levels was the best inclusion level to enhance broiler growth performance, carcass yield, meat yield and meat quality.
- Full Text:
- Date Issued: 2015
Evaluation of incidence of Mycobacterium tuberculosis complex associated with soil, hayfeed and water in three agricultural facilities in Amathole District Municipality in the Eastern Cape Province, South Africa
- Authors: Ntloko, Athini
- Date: 2015
- Subjects: Mycobacterium tuberculosis -- South Africa -- Eastern Cape Drug resistance in microorganisms Mycobacterial diseases
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/2689 , vital:27993
- Description: Mycobacterium bovis and other species of Mycobacterium tuberculosis complex (MTBC) can result to a zoonotic infection known as Bovine tuberculosis (bTB). MTBC has members that may contaminate an extensive range of hosts, including wildlife. Diverse wild species are known to cause disease in domestic livestock and are acknowledged as TB reservoirs. It has been a main study worldwide to deliberate on bTB risk factors as a result some studies focused on particular parts of risk factors such as wildlife and herd management. The objectives of this study were to design questionnaires from commercial farms and smallholding farms; isolate and identify MTBC from collected samples using culture and PCR assays recovered from Fort Hare, Middledrift and Seven star dairy farms; and assessing genotypic drug resistance through detection of mutations conferring resistance to INH and RMP associated with first line treatment for MTBC infection. Questionnaires were administered to thirty (30) smallholding farm owners in the two villages (kwaMasele and Qungqwala) and three (3) three commercial farms (Fort Hare dairy farm, Middledrift dairy farm and Seven-star dairy farm). Detection of M. tuberculosis complex was achieved by Polymerase Chain Reaction using primers for IS6110; whereas a genotypic drug resistance mutation was detected using Genotype MTBDRplus assays. Nine percent (9 percent) of respondents had more than 40 cows in their herd, while 60 percent reported between 10 and 20 cows in their herd. Relationship between farm size and vaccination for TB differed from forty-one percent (41 percent) being the highest to the least five percent (5 percent). The highest number of respondents who knew about relationship between TB cases and cattle location was ninety-one percent (91 percent). Approximately fifty-one percent (51 percent) of respondents had knowledge about wild life access to the farms. Relationship between import of cattle and farm size ranged from nine percent (9 percent) to thirty-five percent (35 percent). Cattle sickness in relation to farm size differed from forty-three (43 percent) being the highest to the least three percent (3 percent); while thirty-three percent (33 percent) of respondents had knowledge about health management. Respondents with knowledge about the occurrence of TB infections in farms were forty-eight percent (48 percent). The frequency of DNA isolation from samples ranged from the highest forty-five percent (45 percent) from water to the least twenty-two percent (22 percent) from soil. Fort Hare dairy farm had the highest number of positive samples forty-four percent (44 percent) from water samples; whereas Middledrift dairy farm had the lowest positive from water, seventeen percent (17 percent). Twelve (22 percent) out of 55 isolates showed resistance to INH and RMP that is, multi-drug resistance (MDR) and nine percent (9 percent) were sensitive to either INH or RMP. The mutations at rpoB gene differed from 58 percent being the highest to the least (23 percent). Fifty-seven percent (57 percent) of samples showed a S315T1 mutation while only 14 percent possessed a S531L in the katG gene. The highest inhA mutations were detected in T8A (80 percent) eighty percent and the least was observed in A16G (17 percent). The results of this study reveals that risk factors for bTB in cattle and dairy farm workers is a serious issue abound in the Eastern Cape of South Africa; with the possibility of widespread dissemination of multidrug resistant determinants in MTBC from the environment.
- Full Text:
- Date Issued: 2015
- Authors: Ntloko, Athini
- Date: 2015
- Subjects: Mycobacterium tuberculosis -- South Africa -- Eastern Cape Drug resistance in microorganisms Mycobacterial diseases
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/2689 , vital:27993
- Description: Mycobacterium bovis and other species of Mycobacterium tuberculosis complex (MTBC) can result to a zoonotic infection known as Bovine tuberculosis (bTB). MTBC has members that may contaminate an extensive range of hosts, including wildlife. Diverse wild species are known to cause disease in domestic livestock and are acknowledged as TB reservoirs. It has been a main study worldwide to deliberate on bTB risk factors as a result some studies focused on particular parts of risk factors such as wildlife and herd management. The objectives of this study were to design questionnaires from commercial farms and smallholding farms; isolate and identify MTBC from collected samples using culture and PCR assays recovered from Fort Hare, Middledrift and Seven star dairy farms; and assessing genotypic drug resistance through detection of mutations conferring resistance to INH and RMP associated with first line treatment for MTBC infection. Questionnaires were administered to thirty (30) smallholding farm owners in the two villages (kwaMasele and Qungqwala) and three (3) three commercial farms (Fort Hare dairy farm, Middledrift dairy farm and Seven-star dairy farm). Detection of M. tuberculosis complex was achieved by Polymerase Chain Reaction using primers for IS6110; whereas a genotypic drug resistance mutation was detected using Genotype MTBDRplus assays. Nine percent (9 percent) of respondents had more than 40 cows in their herd, while 60 percent reported between 10 and 20 cows in their herd. Relationship between farm size and vaccination for TB differed from forty-one percent (41 percent) being the highest to the least five percent (5 percent). The highest number of respondents who knew about relationship between TB cases and cattle location was ninety-one percent (91 percent). Approximately fifty-one percent (51 percent) of respondents had knowledge about wild life access to the farms. Relationship between import of cattle and farm size ranged from nine percent (9 percent) to thirty-five percent (35 percent). Cattle sickness in relation to farm size differed from forty-three (43 percent) being the highest to the least three percent (3 percent); while thirty-three percent (33 percent) of respondents had knowledge about health management. Respondents with knowledge about the occurrence of TB infections in farms were forty-eight percent (48 percent). The frequency of DNA isolation from samples ranged from the highest forty-five percent (45 percent) from water to the least twenty-two percent (22 percent) from soil. Fort Hare dairy farm had the highest number of positive samples forty-four percent (44 percent) from water samples; whereas Middledrift dairy farm had the lowest positive from water, seventeen percent (17 percent). Twelve (22 percent) out of 55 isolates showed resistance to INH and RMP that is, multi-drug resistance (MDR) and nine percent (9 percent) were sensitive to either INH or RMP. The mutations at rpoB gene differed from 58 percent being the highest to the least (23 percent). Fifty-seven percent (57 percent) of samples showed a S315T1 mutation while only 14 percent possessed a S531L in the katG gene. The highest inhA mutations were detected in T8A (80 percent) eighty percent and the least was observed in A16G (17 percent). The results of this study reveals that risk factors for bTB in cattle and dairy farm workers is a serious issue abound in the Eastern Cape of South Africa; with the possibility of widespread dissemination of multidrug resistant determinants in MTBC from the environment.
- Full Text:
- Date Issued: 2015
Evaluation of incidence of Mycobacterium tuberculosis complex associated with soil, hayfeed and water in three Agricultural facilities in Amathole District Municipality in the Eastern Cape Province, South Africa
- Authors: Ntloko, Athini
- Date: 2015
- Language: English
- Type: Thesis , Masters , MSc (Microbiology)
- Identifier: http://hdl.handle.net/10353/756 , vital:26494
- Description: Mycobacterium bovis and other species of Mycobacterium tuberculosis complex (MTBC) can result to a zoonotic infection known as Bovine tuberculosis (bTB). MTBC has members that may contaminate an extensive range of hosts, including wildlife. Diverse wild species are known to cause disease in domestic livestock and are acknowledged as TB reservoirs. It has been a main study worldwide to deliberate on bTB risk factors as a result some studies focused on particular parts of risk factors such as wildlife and herd management. The objectives of this study were to design questionnaires from commercial farms and smallholding farms; isolate and identify MTBC from collected samples using culture and PCR assays recovered from Fort Hare, Middledrift and Seven star dairy farms; and assessing genotypic drug resistance through detection of mutations conferring resistance to INH and RMP associated with first line treatment for MTBC infection. Questionnaires were administered to thirty (30) smallholding farm owners in the two villages (kwaMasele and Qungqwala) and three (3) three commercial farms ( Fort Hare dairy farm, Middledrift dairy farm and Seven star dairy farm). Detection of M. tuberculosis complex was achieved by Polymerase Chain Reaction using primers for IS6110; whereas a genotypic drug resistance mutation was detected using Genotype MTBDRplus assays. Nine percent (9%) of respondents had more than 40 cows in their herd, while 60% reported between 10 and 20 cows in their herd. Relationship between farm size and vaccination for TB differed from forty one percent (41%) being the highest to the least five percent (5%). The highest number of respondents who knew about relationship between TB cases and cattle location was ninety one percent (91%). Approximately fifty one percent (51%) of respondents had knowledge about wild life access to the farms. Relationship between import of cattle and farm size ranged from nine percent (9%) to thirty five percent (35%). Cattle sickness in relation to farm size differed from forty three (43%) being the highest to the least three percent (3%); while thirty three percent (33%) of respondents had knowledge about health management. Respondents with knowledge about the occurrence of TB infections in farms were forty eight percent (48%). The frequency of DNA isolation from samples ranged from the highest forty five percent (45%) from water to the least twenty two percent (22%) from soil. Fort Hare dairy farm had the highest number of positive samples forty four percent (44%) from water samples; whereas Middledrift dairy farm had the lowest positive from water, seventeen percent (17%). Twelve (22%) out of 55 isolates showed resistance to INH and RMP that is, multi-drug resistance (MDR) and nine percent (9%) were sensitive to either INH or RMP. The mutations at rpoB gene differed from 58% being the highest to the least (23%). Fifty seven percent (57%) of samples showed a S315T1 mutation while only 14% possessed a S531L in the katG gene. The highest inhA mutations were detected in T8A (80%) eighty percent and the least was observed in A16G (17%). The results of this study reveals that risk factors for bTB in cattle and dairy farm workers is a serious issue abound in the Eastern Cape of South Africa; with the possibility of widespread dissemination of multidrug resistant determinants in MTBC from the environment.
- Full Text:
- Date Issued: 2015
- Authors: Ntloko, Athini
- Date: 2015
- Language: English
- Type: Thesis , Masters , MSc (Microbiology)
- Identifier: http://hdl.handle.net/10353/756 , vital:26494
- Description: Mycobacterium bovis and other species of Mycobacterium tuberculosis complex (MTBC) can result to a zoonotic infection known as Bovine tuberculosis (bTB). MTBC has members that may contaminate an extensive range of hosts, including wildlife. Diverse wild species are known to cause disease in domestic livestock and are acknowledged as TB reservoirs. It has been a main study worldwide to deliberate on bTB risk factors as a result some studies focused on particular parts of risk factors such as wildlife and herd management. The objectives of this study were to design questionnaires from commercial farms and smallholding farms; isolate and identify MTBC from collected samples using culture and PCR assays recovered from Fort Hare, Middledrift and Seven star dairy farms; and assessing genotypic drug resistance through detection of mutations conferring resistance to INH and RMP associated with first line treatment for MTBC infection. Questionnaires were administered to thirty (30) smallholding farm owners in the two villages (kwaMasele and Qungqwala) and three (3) three commercial farms ( Fort Hare dairy farm, Middledrift dairy farm and Seven star dairy farm). Detection of M. tuberculosis complex was achieved by Polymerase Chain Reaction using primers for IS6110; whereas a genotypic drug resistance mutation was detected using Genotype MTBDRplus assays. Nine percent (9%) of respondents had more than 40 cows in their herd, while 60% reported between 10 and 20 cows in their herd. Relationship between farm size and vaccination for TB differed from forty one percent (41%) being the highest to the least five percent (5%). The highest number of respondents who knew about relationship between TB cases and cattle location was ninety one percent (91%). Approximately fifty one percent (51%) of respondents had knowledge about wild life access to the farms. Relationship between import of cattle and farm size ranged from nine percent (9%) to thirty five percent (35%). Cattle sickness in relation to farm size differed from forty three (43%) being the highest to the least three percent (3%); while thirty three percent (33%) of respondents had knowledge about health management. Respondents with knowledge about the occurrence of TB infections in farms were forty eight percent (48%). The frequency of DNA isolation from samples ranged from the highest forty five percent (45%) from water to the least twenty two percent (22%) from soil. Fort Hare dairy farm had the highest number of positive samples forty four percent (44%) from water samples; whereas Middledrift dairy farm had the lowest positive from water, seventeen percent (17%). Twelve (22%) out of 55 isolates showed resistance to INH and RMP that is, multi-drug resistance (MDR) and nine percent (9%) were sensitive to either INH or RMP. The mutations at rpoB gene differed from 58% being the highest to the least (23%). Fifty seven percent (57%) of samples showed a S315T1 mutation while only 14% possessed a S531L in the katG gene. The highest inhA mutations were detected in T8A (80%) eighty percent and the least was observed in A16G (17%). The results of this study reveals that risk factors for bTB in cattle and dairy farm workers is a serious issue abound in the Eastern Cape of South Africa; with the possibility of widespread dissemination of multidrug resistant determinants in MTBC from the environment.
- Full Text:
- Date Issued: 2015
Experiences of HIV positive clients defaulting isoniazid preventive therapy (IPT) in King Williams Town area under the Buffalo City Municipality in the Eastern Cape Province
- Authors: Williams, Nelisa Colleen
- Date: 2015
- Subjects: AIDS (Disease) -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc (Community Nursing Science)
- Identifier: vital:11923 , http://hdl.handle.net/10353/d1020177 , AIDS (Disease) -- South Africa -- Eastern Cape
- Description: This qualitative study using a phenomenological design, aimed at exploring and describing and exploring the experiences of HIV positive clients defaulting Isoniazid Preventive Therapy services in the Bhisho Primary Health Care Services. The emphasis was on the factors leading clients to default. An in- depth unstructured face to face interviews were done on 14 participants from 4 clinics or facilities under Bhisho Primary Health Care Services. From the respondents’ responses it can be noted that work and family related issues, ignorance of patients, side effects, and negligence of nurses and denial of HIV status were identified as reasons for defaulting. Having knowledge about the treatment and health providers’ attitudes to patients also played a role in patients defaulting their treatment.Many suggestions were then put forward by the respondents to curb defaulting among patients. These included the use of text message reminders, not to discrimination HIV patients because of their status, to use consulting rooms for privacy and also nurses and caregivers to control their attitudes when dealing with patients.
- Full Text:
- Date Issued: 2015
- Authors: Williams, Nelisa Colleen
- Date: 2015
- Subjects: AIDS (Disease) -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc (Community Nursing Science)
- Identifier: vital:11923 , http://hdl.handle.net/10353/d1020177 , AIDS (Disease) -- South Africa -- Eastern Cape
- Description: This qualitative study using a phenomenological design, aimed at exploring and describing and exploring the experiences of HIV positive clients defaulting Isoniazid Preventive Therapy services in the Bhisho Primary Health Care Services. The emphasis was on the factors leading clients to default. An in- depth unstructured face to face interviews were done on 14 participants from 4 clinics or facilities under Bhisho Primary Health Care Services. From the respondents’ responses it can be noted that work and family related issues, ignorance of patients, side effects, and negligence of nurses and denial of HIV status were identified as reasons for defaulting. Having knowledge about the treatment and health providers’ attitudes to patients also played a role in patients defaulting their treatment.Many suggestions were then put forward by the respondents to curb defaulting among patients. These included the use of text message reminders, not to discrimination HIV patients because of their status, to use consulting rooms for privacy and also nurses and caregivers to control their attitudes when dealing with patients.
- Full Text:
- Date Issued: 2015
Exploring user experience (UX) factors For ICTD services
- Authors: Nyambi, Pride Bongiwe
- Date: 2015
- Language: English
- Type: Thesis , Masters , MSc (Computer Science)
- Identifier: vital:11400 , http://hdl.handle.net/10353/d1020164
- Description: Consistent with global entities such as the United Nations- through the World Summit of the Information Society (WSIS), introduction of Information and Communication Technology (ICT) for human development has seen the introduction of ICT-based services aimed at facilitating socio-economic development of marginalized communities. The use of ICTs has always solicited the concept of Human Computer Interaction (HCI), which involves the methods which humans interact with technology. The types of User Interfaces (UIs) and interaction techniques that people use to interact with ICTs affects the way they perceive technology and eventually, their acceptance of the technology. Current ICT systems still haven‟t adopted the concept of placing the user at the core of the interaction. Users are still required to adapt themselves to the interface‟s characteristics; which limits the number of people who can use the system due to inabilities to adapt to the interface. As a result, the information embedded in these technologies is still inaccessible and useless to Marginalized Rural Area (MRA) users. Such usability challenges can be mitigated against and avoided by matching UI components with the users‟ mental models, language, preferences, needs and other socio-cultural artefacts. In this research, literature in Human-Computer Interaction (HCI) is reviewed with emphasis on the usability and User Experience (UX) during user interaction with ICTs using various modes of interactions. HCI emphasizes the need for systems to take account of user‟s characteristics such as their abilities, needs, socio-cultural experiences, behaviours and interests. In efforts to meet the requirement of UX, the user, system and the context of use, need to be evaluated, taking into consideration that changing one entity modifies the UX. This will be achieved by persona profiling to determine the key characteristics of the user communities, clustered according to the key UX attributes. Subsequently, through detailed usability evaluations, including the use of System Usability Scale (SUS) to determine user satisfaction with various UI components/techniques per identified persona- thus providing and persona mapping for usability of Information and Communication Technology for Development (ICTD) services. The results from this research are reflective of the importance of creating personas for usability testing. Some of the personas do not have a problem with interacting with most of the interfaces but their choice of interface comes from a preference point of view. For some personas, their skills and level of experience with ICTs motivates their choice of interface. The common UI component that users from across the spectrum appreciate is UI consistency which makes interaction easier and more natural. Common obstacles with current User Interfaces (UIs) that inhibit users from MRAs include the hefty use of text in interfaces, unintuitive navigation structures and the use of a foreign language. Differences in UIs from different application developers present an inconsistency which challenges the users from rural areas. These differences include the layout, the text entry methods and the form of output produced. A solution to this has been identified from the usability test as the use of speech-enabled interfaces in a language that can be understood by the target audience. In addition, through literature study it has been found that UX of interfaces can be improved by the use of less textual or text-free interfaces. Based on literature, users from MRAs can benefit from using hand-writing based UIs for text-based entry which mimics pen and paper environment for literate users who have experience with writing. Finally, the use of numbered options can assist illiterate users in tasks that requires users to choose options and for navigation. Therefore, consistency in UIs designed to be used by MRA users can improve usability of these interfaces and thus, improving the overall UX.
- Full Text:
- Date Issued: 2015
- Authors: Nyambi, Pride Bongiwe
- Date: 2015
- Language: English
- Type: Thesis , Masters , MSc (Computer Science)
- Identifier: vital:11400 , http://hdl.handle.net/10353/d1020164
- Description: Consistent with global entities such as the United Nations- through the World Summit of the Information Society (WSIS), introduction of Information and Communication Technology (ICT) for human development has seen the introduction of ICT-based services aimed at facilitating socio-economic development of marginalized communities. The use of ICTs has always solicited the concept of Human Computer Interaction (HCI), which involves the methods which humans interact with technology. The types of User Interfaces (UIs) and interaction techniques that people use to interact with ICTs affects the way they perceive technology and eventually, their acceptance of the technology. Current ICT systems still haven‟t adopted the concept of placing the user at the core of the interaction. Users are still required to adapt themselves to the interface‟s characteristics; which limits the number of people who can use the system due to inabilities to adapt to the interface. As a result, the information embedded in these technologies is still inaccessible and useless to Marginalized Rural Area (MRA) users. Such usability challenges can be mitigated against and avoided by matching UI components with the users‟ mental models, language, preferences, needs and other socio-cultural artefacts. In this research, literature in Human-Computer Interaction (HCI) is reviewed with emphasis on the usability and User Experience (UX) during user interaction with ICTs using various modes of interactions. HCI emphasizes the need for systems to take account of user‟s characteristics such as their abilities, needs, socio-cultural experiences, behaviours and interests. In efforts to meet the requirement of UX, the user, system and the context of use, need to be evaluated, taking into consideration that changing one entity modifies the UX. This will be achieved by persona profiling to determine the key characteristics of the user communities, clustered according to the key UX attributes. Subsequently, through detailed usability evaluations, including the use of System Usability Scale (SUS) to determine user satisfaction with various UI components/techniques per identified persona- thus providing and persona mapping for usability of Information and Communication Technology for Development (ICTD) services. The results from this research are reflective of the importance of creating personas for usability testing. Some of the personas do not have a problem with interacting with most of the interfaces but their choice of interface comes from a preference point of view. For some personas, their skills and level of experience with ICTs motivates their choice of interface. The common UI component that users from across the spectrum appreciate is UI consistency which makes interaction easier and more natural. Common obstacles with current User Interfaces (UIs) that inhibit users from MRAs include the hefty use of text in interfaces, unintuitive navigation structures and the use of a foreign language. Differences in UIs from different application developers present an inconsistency which challenges the users from rural areas. These differences include the layout, the text entry methods and the form of output produced. A solution to this has been identified from the usability test as the use of speech-enabled interfaces in a language that can be understood by the target audience. In addition, through literature study it has been found that UX of interfaces can be improved by the use of less textual or text-free interfaces. Based on literature, users from MRAs can benefit from using hand-writing based UIs for text-based entry which mimics pen and paper environment for literate users who have experience with writing. Finally, the use of numbered options can assist illiterate users in tasks that requires users to choose options and for navigation. Therefore, consistency in UIs designed to be used by MRA users can improve usability of these interfaces and thus, improving the overall UX.
- Full Text:
- Date Issued: 2015
Factors affecting participation rates in farming in the rural areas of South Africa: case of Amathole District Municipality
- Authors: Zamxaka, Xolisa
- Date: 2015
- Subjects: Agricultural systems -- South Africa -- Eastern Cape , Rural development -- South Africa -- Eastern Cape , Sustainable development -- South Africa -- Eastern Cape , Farms, Small -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc Agric (Agricultural Economics)
- Identifier: vital:11233 , http://hdl.handle.net/10353/d1021291 , Agricultural systems -- South Africa -- Eastern Cape , Rural development -- South Africa -- Eastern Cape , Sustainable development -- South Africa -- Eastern Cape , Farms, Small -- South Africa -- Eastern Cape
- Description: South Africa and the rest of developing countries are faced with poverty and poor rural development. Rural participation in agricultural activities is one of the components that can be used to address the poverty challenge facing the people residing in rural areas. The broad objective of this research is to determine factors affecting participation rate in farming in the rural areas of Amathole District Municipality of Eastern Cape. In this study stratified random sampling method was applied in order to choose a sample out of 30 households that were interviewed 13 people belonged to Participants and 17 people belonged to non-Participants. The results from this study show that women participate a lot in farming activities. The multiple regression model was used to test the participation rates of the people in Amathole region specifically Phumlani area. A number of variables were considered in this study to assess the impact of different variables on participation in farming activities. The results showed that about 57% of the respondents are not participating in farming while 43% of the respondents participate. The farming participants that were interviewed all claim that there is a lack in farming support in the area. When there is no support of any kind, rural people would not be motivated to start development projects on their own. Consequently, this lack of farming support in the Phumlani area may have an influence on the number of farming participants. Therefore, the lack of support in the area may serve as a motivation for non-participants not to be influenced to farm. Rural farming needs to be promoted amongst the youth so as to protect and sustain agricultural growth in rural areas. The study has discovered that the youth of Phumlani is not actively involved in farming activities. Government can provide community members with farming resources so as to promote farming in the area. It would be wiser for the government to provide physical farming resources and implements rather than cash grants.
- Full Text:
- Date Issued: 2015
- Authors: Zamxaka, Xolisa
- Date: 2015
- Subjects: Agricultural systems -- South Africa -- Eastern Cape , Rural development -- South Africa -- Eastern Cape , Sustainable development -- South Africa -- Eastern Cape , Farms, Small -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc Agric (Agricultural Economics)
- Identifier: vital:11233 , http://hdl.handle.net/10353/d1021291 , Agricultural systems -- South Africa -- Eastern Cape , Rural development -- South Africa -- Eastern Cape , Sustainable development -- South Africa -- Eastern Cape , Farms, Small -- South Africa -- Eastern Cape
- Description: South Africa and the rest of developing countries are faced with poverty and poor rural development. Rural participation in agricultural activities is one of the components that can be used to address the poverty challenge facing the people residing in rural areas. The broad objective of this research is to determine factors affecting participation rate in farming in the rural areas of Amathole District Municipality of Eastern Cape. In this study stratified random sampling method was applied in order to choose a sample out of 30 households that were interviewed 13 people belonged to Participants and 17 people belonged to non-Participants. The results from this study show that women participate a lot in farming activities. The multiple regression model was used to test the participation rates of the people in Amathole region specifically Phumlani area. A number of variables were considered in this study to assess the impact of different variables on participation in farming activities. The results showed that about 57% of the respondents are not participating in farming while 43% of the respondents participate. The farming participants that were interviewed all claim that there is a lack in farming support in the area. When there is no support of any kind, rural people would not be motivated to start development projects on their own. Consequently, this lack of farming support in the Phumlani area may have an influence on the number of farming participants. Therefore, the lack of support in the area may serve as a motivation for non-participants not to be influenced to farm. Rural farming needs to be promoted amongst the youth so as to protect and sustain agricultural growth in rural areas. The study has discovered that the youth of Phumlani is not actively involved in farming activities. Government can provide community members with farming resources so as to promote farming in the area. It would be wiser for the government to provide physical farming resources and implements rather than cash grants.
- Full Text:
- Date Issued: 2015
Geological and geophysical investigation of the South Eastern Karoo Basin, South Africa
- Authors: Baiyegunhi, Christopher
- Date: 2015
- Language: English
- Type: Thesis , Masters , MSc (Geology)
- Identifier: vital:11532 , http://hdl.handle.net/10353/d1021280
- Description: Geological and geophysical methods were used to investigate the southeastern Karoo Basin of South Africa in an area extending from longitudes 24 o E to 29o E and latitudes 32o S to 35o S. This was undertaken in order to reveal geologic structures, isochore thicknesses of the geologic sequence and their variations across the study area, proffer the possible provenance of the sediments and assess the potential of oil and gas accumulation. The methodology used includes field investigation, rock sampling, preparation of thin sections, petrographic studies, X-ray diffraction analysis, density measurements, porosity calculations, extraction of elevation data from Google Earth, 2½ D gravity profile modelling, generating of isochore (true vertical) thicknesses and depositional surfaces maps from the models, PetroMod 1D modelling and qualitative interpretation of magnetic, gravity and radiometric maps.Petrographic study was carried out on twenty six thin sections of rocks from the eleven geologic formations that cover the study area. Petrographic studies on the diamictite of the Dwyka Group shows abundance of monocrystalline quartz, granite and quartzite components in the breccias which possibly indicate the existence of granitic and metamorphic rocks in the source areas. The sandstones of the Ecca and Beaufort Groups are immature, greywacke and the heavy mineral assemblages signify that the minerals are of granitic, volcanic and metamorphic origin. The magnetic maps show two main magnetic anomalies, a major one trending in a northeast to southwest direction which is part of the Beattie magnetic anomaly and another that is a “bean-shaped” anomaly. The radially averaged power spectrum shows two depths to magnetic sources. The first depth is about 0.6 km which is the average depth to the top of the shallow sources, while the average depth to the top of the deep sources is about 15 km. The shallow sources are connected to magnetic minerals within the Beaufort Group while deep magnetic sources were inferred to be in the basement. The gamma ray spectrometric map shows areas with relatively high gamma radiation count. The high radiation count is possibly due to the uranium and thorium in the detrital materials, as well as the enrichment of radioelements in the feldspars (k-feldspar), calcite, quartz, zircon and clay minerals in the fluvial channel sandstones of the Beaufort Group. A total of two hundred and fifty-eight (258) rock samples were collected in the field and densities (dry, wet and grain densities) and porosities were determined in the laboratory. The Karoo Supergroup density values range from 2.526 – 2.828 g/cm3. The average porosities range from 0. 49 – 3.31 %. The dry densities and porosities of all the formations are inversely correlated with correlation coefficient values (R) that range from 0.9491 - 0.9982. The density of the dolerite intrusions (mostly sill) ranges from 2.700 – 2.837 g/cm3 whilst the porosity range from 0.1118 – 0.3868 %. The Bouguer anomaly map shows an increase in gravity values from -140.7 mGal in inland to about 60.1 mGal in coastal areas. This dominant gravity variation is inferred to be due to a deeper basement and/or Moho that get shallower from inland towards the coast. The Moho is at about 45 km depth inland and shallows to about 42 km at the coast. The 2½ D gravity modelling was done for fourteen (14) profiles with each profile having three (3) models corresponding to minimum, average and maximum densities to obtain the thicknesses of the geologic sequence. The current isochore thicknesses extracted from the gravity models show that the Beaufort Group is the thickest of all the groups that make up the Karoo Supergroup with maximum vertical thickness of up to 634 m, followed by the Ecca and Dwyka Groups with maximum vertical thicknesses of about 3207 m and 727 m, respectively. The maximum elevation for the Dwyka, Ecca and Beaufort sediments are about 500 m, 400 m and 285 m, respectively, whilst the maximum depth below sea level are around 8500 m, 7000 m and 5500 m, respectively. The PetroMod1D model result yield average vitrinite reflectance and temperature values of about 6 % and 500 ℃ respectively for the lower Ecca Group which belong to the dry gas window based on classification by several authors. Thus the rocks of the lower Ecca Group are thermally matured for hydrocarbon (shale gas) generation that can merit gas exploration in the Karoo Basin.
- Full Text:
- Date Issued: 2015
- Authors: Baiyegunhi, Christopher
- Date: 2015
- Language: English
- Type: Thesis , Masters , MSc (Geology)
- Identifier: vital:11532 , http://hdl.handle.net/10353/d1021280
- Description: Geological and geophysical methods were used to investigate the southeastern Karoo Basin of South Africa in an area extending from longitudes 24 o E to 29o E and latitudes 32o S to 35o S. This was undertaken in order to reveal geologic structures, isochore thicknesses of the geologic sequence and their variations across the study area, proffer the possible provenance of the sediments and assess the potential of oil and gas accumulation. The methodology used includes field investigation, rock sampling, preparation of thin sections, petrographic studies, X-ray diffraction analysis, density measurements, porosity calculations, extraction of elevation data from Google Earth, 2½ D gravity profile modelling, generating of isochore (true vertical) thicknesses and depositional surfaces maps from the models, PetroMod 1D modelling and qualitative interpretation of magnetic, gravity and radiometric maps.Petrographic study was carried out on twenty six thin sections of rocks from the eleven geologic formations that cover the study area. Petrographic studies on the diamictite of the Dwyka Group shows abundance of monocrystalline quartz, granite and quartzite components in the breccias which possibly indicate the existence of granitic and metamorphic rocks in the source areas. The sandstones of the Ecca and Beaufort Groups are immature, greywacke and the heavy mineral assemblages signify that the minerals are of granitic, volcanic and metamorphic origin. The magnetic maps show two main magnetic anomalies, a major one trending in a northeast to southwest direction which is part of the Beattie magnetic anomaly and another that is a “bean-shaped” anomaly. The radially averaged power spectrum shows two depths to magnetic sources. The first depth is about 0.6 km which is the average depth to the top of the shallow sources, while the average depth to the top of the deep sources is about 15 km. The shallow sources are connected to magnetic minerals within the Beaufort Group while deep magnetic sources were inferred to be in the basement. The gamma ray spectrometric map shows areas with relatively high gamma radiation count. The high radiation count is possibly due to the uranium and thorium in the detrital materials, as well as the enrichment of radioelements in the feldspars (k-feldspar), calcite, quartz, zircon and clay minerals in the fluvial channel sandstones of the Beaufort Group. A total of two hundred and fifty-eight (258) rock samples were collected in the field and densities (dry, wet and grain densities) and porosities were determined in the laboratory. The Karoo Supergroup density values range from 2.526 – 2.828 g/cm3. The average porosities range from 0. 49 – 3.31 %. The dry densities and porosities of all the formations are inversely correlated with correlation coefficient values (R) that range from 0.9491 - 0.9982. The density of the dolerite intrusions (mostly sill) ranges from 2.700 – 2.837 g/cm3 whilst the porosity range from 0.1118 – 0.3868 %. The Bouguer anomaly map shows an increase in gravity values from -140.7 mGal in inland to about 60.1 mGal in coastal areas. This dominant gravity variation is inferred to be due to a deeper basement and/or Moho that get shallower from inland towards the coast. The Moho is at about 45 km depth inland and shallows to about 42 km at the coast. The 2½ D gravity modelling was done for fourteen (14) profiles with each profile having three (3) models corresponding to minimum, average and maximum densities to obtain the thicknesses of the geologic sequence. The current isochore thicknesses extracted from the gravity models show that the Beaufort Group is the thickest of all the groups that make up the Karoo Supergroup with maximum vertical thickness of up to 634 m, followed by the Ecca and Dwyka Groups with maximum vertical thicknesses of about 3207 m and 727 m, respectively. The maximum elevation for the Dwyka, Ecca and Beaufort sediments are about 500 m, 400 m and 285 m, respectively, whilst the maximum depth below sea level are around 8500 m, 7000 m and 5500 m, respectively. The PetroMod1D model result yield average vitrinite reflectance and temperature values of about 6 % and 500 ℃ respectively for the lower Ecca Group which belong to the dry gas window based on classification by several authors. Thus the rocks of the lower Ecca Group are thermally matured for hydrocarbon (shale gas) generation that can merit gas exploration in the Karoo Basin.
- Full Text:
- Date Issued: 2015
Identification and documentation of ethnobiological methods used by rural farmers to control stalk borers on maize in the Eastern Cape Province of South Africa
- Authors: Skenjana, Nolitha Leonora
- Date: 2015
- Subjects: Ethnobotany , Stem borers , Biological pest control agents -- South Africa , Corn -- Diseases and pests -- South Africa
- Language: English
- Type: Thesis , Masters , MSc (Ethnobotany)
- Identifier: vital:11312 , http://hdl.handle.net/10353/d1019852 , Ethnobotany , Stem borers , Biological pest control agents -- South Africa , Corn -- Diseases and pests -- South Africa
- Description: Maize contributes substantially to food security in the Eastern Cape province of South Africa. It is a staple food to many of the province’s rural and urban inhabitants. Insect pests are one of the factors that hamper its productivity and as a result, deprive farmers of good yields. The adverse effects of insecticides and the high cost associated with them and the cost of transgenic seeds are some of the challenges faced by small-scale farmers in rural areas. Alternative control methods which include the use of indigenous techniques to control pests are now sought. A study to identify and document ethnobiological means used by rural farmers to manage insect pests of maize was conducted in the rural areas of the Eastern Cape Province. A total of 217 participants were interviewed on the matter, using semi-structured but detailed questionnaires. Rural farmers due to their linkage to agriculture activities and the fact that they are considered as custodians of agricultural indigenous knowledge were selected as respondents. Only maize producing and IsiXhosa speaking people were chosen to contribute. Main focus was on the demography of respondents, crop production activities and insect pest control. Pretesting of the questionnaire in order to assess the appropriateness of questions and comprehension by both farmers and enumerators was done. Data was analysed using descriptive statistics. Fifty five percent (55 %) of the respondents were females and the highest number of participants was from the Chris Hani District Municipality. Majority of the people were unemployed or pensioners. Most had only attended primary school and the mean age was 59 years. Apart from maize, respondents were cultivating other crops such as cabbage, Swiss chard, potatoes etc. Stalk borers followed by cutworms were the main pests of maize in these areas. Respondents used mainly insecticides, followed by alternative substances, which also included cultural control methods such as planting date manipulation. Few respondents used plants as control agents for insect pests. Some people did not control pests even though they were a problem in their fields. The most used plant was Chenopodium ambrosiodes L, while the most used substance was Madubula (a detergent). The most used insecticide was carbaryl from the carbamite family. Respondents listed different preparation techniques for all the control methods mentioned. These techniques revealed different times of preparation, quantities of ingredients, amounts applied on plants, modes of application and intervals of application. Rural farmers in the study areas used different atypical methods which may play a significant role in pest management today. Some of the products may have a positive influence on agriculture, while some are dangerous to humans and environmental health. Further research which will investigate their potential use in pest control needs to be done.
- Full Text:
- Date Issued: 2015
- Authors: Skenjana, Nolitha Leonora
- Date: 2015
- Subjects: Ethnobotany , Stem borers , Biological pest control agents -- South Africa , Corn -- Diseases and pests -- South Africa
- Language: English
- Type: Thesis , Masters , MSc (Ethnobotany)
- Identifier: vital:11312 , http://hdl.handle.net/10353/d1019852 , Ethnobotany , Stem borers , Biological pest control agents -- South Africa , Corn -- Diseases and pests -- South Africa
- Description: Maize contributes substantially to food security in the Eastern Cape province of South Africa. It is a staple food to many of the province’s rural and urban inhabitants. Insect pests are one of the factors that hamper its productivity and as a result, deprive farmers of good yields. The adverse effects of insecticides and the high cost associated with them and the cost of transgenic seeds are some of the challenges faced by small-scale farmers in rural areas. Alternative control methods which include the use of indigenous techniques to control pests are now sought. A study to identify and document ethnobiological means used by rural farmers to manage insect pests of maize was conducted in the rural areas of the Eastern Cape Province. A total of 217 participants were interviewed on the matter, using semi-structured but detailed questionnaires. Rural farmers due to their linkage to agriculture activities and the fact that they are considered as custodians of agricultural indigenous knowledge were selected as respondents. Only maize producing and IsiXhosa speaking people were chosen to contribute. Main focus was on the demography of respondents, crop production activities and insect pest control. Pretesting of the questionnaire in order to assess the appropriateness of questions and comprehension by both farmers and enumerators was done. Data was analysed using descriptive statistics. Fifty five percent (55 %) of the respondents were females and the highest number of participants was from the Chris Hani District Municipality. Majority of the people were unemployed or pensioners. Most had only attended primary school and the mean age was 59 years. Apart from maize, respondents were cultivating other crops such as cabbage, Swiss chard, potatoes etc. Stalk borers followed by cutworms were the main pests of maize in these areas. Respondents used mainly insecticides, followed by alternative substances, which also included cultural control methods such as planting date manipulation. Few respondents used plants as control agents for insect pests. Some people did not control pests even though they were a problem in their fields. The most used plant was Chenopodium ambrosiodes L, while the most used substance was Madubula (a detergent). The most used insecticide was carbaryl from the carbamite family. Respondents listed different preparation techniques for all the control methods mentioned. These techniques revealed different times of preparation, quantities of ingredients, amounts applied on plants, modes of application and intervals of application. Rural farmers in the study areas used different atypical methods which may play a significant role in pest management today. Some of the products may have a positive influence on agriculture, while some are dangerous to humans and environmental health. Further research which will investigate their potential use in pest control needs to be done.
- Full Text:
- Date Issued: 2015
Identification of agricultural and industrial pollutants in the Kat River, Eastern Cape and their effect on agricultural products found along the river banks
- Authors: Mutingwende, Nhamo
- Date: 2015
- Subjects: Environmental toxicology , Rivers -- Environmental aspects -- South Africa , Water -- Pollution -- Toxicology -- South Africa
- Language: English
- Type: Thesis , Masters , MSc (Biochemistry)
- Identifier: vital:11291 , http://hdl.handle.net/10353/d1020242 , Environmental toxicology , Rivers -- Environmental aspects -- South Africa , Water -- Pollution -- Toxicology -- South Africa
- Description: There is growing concern that commonly used Pharmaceuticals and Personal Care Products (PPCPs) and pesticides are entering and contaminating drinking water supplies. The use of targeted quantitation of PPCP has been well established but there is an emerging trend to also screen for and identify unexpected environmental pollutants. Chemicals like pesticides hormones and antibiotics are especially of interest because of proven endocrine disrupting effects and a possible development of bacterial resistance. Powerful screening methods are required to detect and quantify the presence of these compounds in our environment. PPCP encompass a wide range of pollutants, including Endocrine Disrupting Compounds (EDC), pesticides, hormones, antibiotics, drugs of abuse, x-ray contrast agents and drinking water disinfection by-products to name a few. In order to properly assess the effects of these compounds on our environment, it is necessary to accurately monitor their presence. The diversity of chemical properties of these compounds makes method development challenging. LC/MS/MS is able to analyse polar, semi-volatile, and thermally labile compounds covering a wide molecular weight range. The new AB SCIEX TripleTOF™5600 LC/MS/MS was used to profile environmental samples for unexpected pollutants, to identify and characterise the chemical composition and structure of the pollutants, and to quantify (based on intensity) the concentration in collected water samples. Liquid Chromatography coupled to tandem Mass Spectrometry (LCMS/ MS) is able to analyse polar, semi-volatile, and thermally labile compounds covering a wide molecular weight range, such as pesticides, antibiotics, drugs of abuse, x-ray contrast agents, drinking water disinfection by-products etc. More recently there is a growing interest from environmental researchers to also screen for and identify non-targeted compounds in environmental samples, including metabolites and degradates, but also completely unexpected pollutants. The new AB SCIEX TripleTOF™5600 LC/MS/MS system is capable of performing highly sensitive and fast MS scanning experiments to search for unknown molecular ions while also performing selective and characteristic MS/MS scanning for further compound identification and, therefore, is the instrument of choice for this challenging task. General unknown screening workflows do not use a target analyte list and compound detection is not based on any prior knowledge, including retention times and information on possible molecular and fragment ions. Therefore, acquired chromatograms are very rich in information and can easily contain thousands of ions from both any compounds present in the sample as well as from the sample matrix itself. Thus, powerful software tools are needed to explore such data to identify the unexpected compound. Water samples were collected both upstream and downstream of two WWTPs (Seymour and Fort Beaufort) and were directly injected on the AB SCIEX TripleTOF™5600 LC/MS/MS after being filtered. 15 sample points along the Kat River, ranging from a point as close to the source as possible to a point just before it joins the Great Fish River were used. The samples collected from the source were used as the control in each of the experiments, the assumption being the closer you get to the source, the less contaminated the water would be for the analysis of pesticides. Points were selected where the Kat River crosses the R67 or on farms where the river was accessible using farm roads. Samples were collected from October 2013 to November 2014.The Peak view software and Analyst software were used in the analysis of PPCPs. The XIC Manager allows you to manage large lists of compounds and perform automatic extracted ion chromatogram (XIC) calculations and review results operations. The results were displayed in the chromatogram pane and the XIC table (see results). The results reported here in this thesis indicate that there is contamination in the Kat River water due to both pesticides and PPCPs. The results also indicate that the food products are also contaminated and hence both the Kat River agricultural produce and its water need to be closely monitored for both pesticide and PPCPs contaminants. Further studies to investigate the quantitative levels of pesticides and PPCPs in the Kat river water to determine if the concentration levels of the detected pesticides are below the reported Maximum Residues Limits will be explored in the future.
- Full Text:
- Date Issued: 2015
- Authors: Mutingwende, Nhamo
- Date: 2015
- Subjects: Environmental toxicology , Rivers -- Environmental aspects -- South Africa , Water -- Pollution -- Toxicology -- South Africa
- Language: English
- Type: Thesis , Masters , MSc (Biochemistry)
- Identifier: vital:11291 , http://hdl.handle.net/10353/d1020242 , Environmental toxicology , Rivers -- Environmental aspects -- South Africa , Water -- Pollution -- Toxicology -- South Africa
- Description: There is growing concern that commonly used Pharmaceuticals and Personal Care Products (PPCPs) and pesticides are entering and contaminating drinking water supplies. The use of targeted quantitation of PPCP has been well established but there is an emerging trend to also screen for and identify unexpected environmental pollutants. Chemicals like pesticides hormones and antibiotics are especially of interest because of proven endocrine disrupting effects and a possible development of bacterial resistance. Powerful screening methods are required to detect and quantify the presence of these compounds in our environment. PPCP encompass a wide range of pollutants, including Endocrine Disrupting Compounds (EDC), pesticides, hormones, antibiotics, drugs of abuse, x-ray contrast agents and drinking water disinfection by-products to name a few. In order to properly assess the effects of these compounds on our environment, it is necessary to accurately monitor their presence. The diversity of chemical properties of these compounds makes method development challenging. LC/MS/MS is able to analyse polar, semi-volatile, and thermally labile compounds covering a wide molecular weight range. The new AB SCIEX TripleTOF™5600 LC/MS/MS was used to profile environmental samples for unexpected pollutants, to identify and characterise the chemical composition and structure of the pollutants, and to quantify (based on intensity) the concentration in collected water samples. Liquid Chromatography coupled to tandem Mass Spectrometry (LCMS/ MS) is able to analyse polar, semi-volatile, and thermally labile compounds covering a wide molecular weight range, such as pesticides, antibiotics, drugs of abuse, x-ray contrast agents, drinking water disinfection by-products etc. More recently there is a growing interest from environmental researchers to also screen for and identify non-targeted compounds in environmental samples, including metabolites and degradates, but also completely unexpected pollutants. The new AB SCIEX TripleTOF™5600 LC/MS/MS system is capable of performing highly sensitive and fast MS scanning experiments to search for unknown molecular ions while also performing selective and characteristic MS/MS scanning for further compound identification and, therefore, is the instrument of choice for this challenging task. General unknown screening workflows do not use a target analyte list and compound detection is not based on any prior knowledge, including retention times and information on possible molecular and fragment ions. Therefore, acquired chromatograms are very rich in information and can easily contain thousands of ions from both any compounds present in the sample as well as from the sample matrix itself. Thus, powerful software tools are needed to explore such data to identify the unexpected compound. Water samples were collected both upstream and downstream of two WWTPs (Seymour and Fort Beaufort) and were directly injected on the AB SCIEX TripleTOF™5600 LC/MS/MS after being filtered. 15 sample points along the Kat River, ranging from a point as close to the source as possible to a point just before it joins the Great Fish River were used. The samples collected from the source were used as the control in each of the experiments, the assumption being the closer you get to the source, the less contaminated the water would be for the analysis of pesticides. Points were selected where the Kat River crosses the R67 or on farms where the river was accessible using farm roads. Samples were collected from October 2013 to November 2014.The Peak view software and Analyst software were used in the analysis of PPCPs. The XIC Manager allows you to manage large lists of compounds and perform automatic extracted ion chromatogram (XIC) calculations and review results operations. The results were displayed in the chromatogram pane and the XIC table (see results). The results reported here in this thesis indicate that there is contamination in the Kat River water due to both pesticides and PPCPs. The results also indicate that the food products are also contaminated and hence both the Kat River agricultural produce and its water need to be closely monitored for both pesticide and PPCPs contaminants. Further studies to investigate the quantitative levels of pesticides and PPCPs in the Kat river water to determine if the concentration levels of the detected pesticides are below the reported Maximum Residues Limits will be explored in the future.
- Full Text:
- Date Issued: 2015