The reproductive biology of warty sea cucumber, Neostichopus grammatus Clark (Holothuroidea: Echinodermata) under natural and integrated multi-trophic aquaculture (IMTA) conditions in the Eastern Cape Province, South Africa
- Authors: Senekal, Heleen Ester
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/464451 , vital:76512
- Description: This study investigated the reproductive cycle of the warty sea cucumber, Neostichopus grammatus, in the wild and in a farming environment, to test its suitability for co-culture with abalone Haliotis midae in an IMTA system. The research formed part of a broader EU H2020 program, Aquavitae, and was conducted at Wild Coast Abalone in South Africa. The study investigated several environmental parameters, such as temperature, day length, and substrate, to determine if these have any effects on the gonadal development and reproductive cycle. The natural gametogenic cycle of wild warty sea cucumbers was determined by monitoring the Gonadosomatic Index (GI) values monthly for a period of 16 months. The GI index was validated by means of other maturity assessment techniques including measurement of the size and colour of the gonads, oocyte diameter measurements and gonad histology sections. Wild collected sea cucumbers were maintained in abalone farm rearing tanks on a diet of abalone feed and faecal waste for a period of 10 months, with GI values being determined monthly. The wild and farmed sea cucumber GI data was correlated with environmental parameters. Seasonal water temperature was strongly correlated with the GI values of wild warty sea cucumbers, suggesting that water temperature likely influences gonadal development. Sea cucumbers matured sexually during colder months (May to September) and spawned from September to February, during summer. The results of oocyte measurements, macroscopic and microscopic analyses, and histological analyses in combination with the GI values, provides a practical indicator of sexual maturity for captive breeding purposes. Farmed warty sea cucumbers followed the same annual reproductive cycle as wild sea cucumbers, however they came into spawning condition approximately one month later than wild conspecifics. As the farm water temperature was significantly higher than the ambient ocean water temperature, it was hypothesised that this may have affected the gonadal development of the farmed sea cucumbers. Furthermore, the farm-reared sea cucumbers lost weight and condition, indicating a nutritional deficiency. Previous studies indicated that the presence of a sand sediment facilitated the assimilation of organic detrital matter by sea cucumbers. An additional trial was thus set up to determine the effect of a sand sediment and cooler ambient temperature on the growth and gonadal development of the warty sea cucumbers. The growth and GI values of sea cucumbers in the cool water treatment did not differ significantly from the ambient temperature control groups. However, the addition of a sand substrate to the sea cucumber tanks had a significant positive growth effect on sea cucumber body mass and GI values. Sea cucumbers fed a diet of abalone waste material on the sand substrate exhibited final average GI values of 2.99 % (SE ±0.56). In contrast, sea cucumbers kept in bare tanks and only received abalone waste as food had significantly lower average GI values of 1.36 % (SE±0.2). This suggests that the provision of a sand sustrate in sea cucumber rearing containers is essential for the adequate nutrition and gonadal development. The results of this study indicate that the warty sea cucumber is a promising candidate for inlcusion in an IMTA system with South African perlemoen abalone. , Thesis (MSc) -- Faculty of Science, Ichthyology and Fisheries Science, 2024
- Full Text:
- Date Issued: 2024-10-11
- Authors: Senekal, Heleen Ester
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/464451 , vital:76512
- Description: This study investigated the reproductive cycle of the warty sea cucumber, Neostichopus grammatus, in the wild and in a farming environment, to test its suitability for co-culture with abalone Haliotis midae in an IMTA system. The research formed part of a broader EU H2020 program, Aquavitae, and was conducted at Wild Coast Abalone in South Africa. The study investigated several environmental parameters, such as temperature, day length, and substrate, to determine if these have any effects on the gonadal development and reproductive cycle. The natural gametogenic cycle of wild warty sea cucumbers was determined by monitoring the Gonadosomatic Index (GI) values monthly for a period of 16 months. The GI index was validated by means of other maturity assessment techniques including measurement of the size and colour of the gonads, oocyte diameter measurements and gonad histology sections. Wild collected sea cucumbers were maintained in abalone farm rearing tanks on a diet of abalone feed and faecal waste for a period of 10 months, with GI values being determined monthly. The wild and farmed sea cucumber GI data was correlated with environmental parameters. Seasonal water temperature was strongly correlated with the GI values of wild warty sea cucumbers, suggesting that water temperature likely influences gonadal development. Sea cucumbers matured sexually during colder months (May to September) and spawned from September to February, during summer. The results of oocyte measurements, macroscopic and microscopic analyses, and histological analyses in combination with the GI values, provides a practical indicator of sexual maturity for captive breeding purposes. Farmed warty sea cucumbers followed the same annual reproductive cycle as wild sea cucumbers, however they came into spawning condition approximately one month later than wild conspecifics. As the farm water temperature was significantly higher than the ambient ocean water temperature, it was hypothesised that this may have affected the gonadal development of the farmed sea cucumbers. Furthermore, the farm-reared sea cucumbers lost weight and condition, indicating a nutritional deficiency. Previous studies indicated that the presence of a sand sediment facilitated the assimilation of organic detrital matter by sea cucumbers. An additional trial was thus set up to determine the effect of a sand sediment and cooler ambient temperature on the growth and gonadal development of the warty sea cucumbers. The growth and GI values of sea cucumbers in the cool water treatment did not differ significantly from the ambient temperature control groups. However, the addition of a sand substrate to the sea cucumber tanks had a significant positive growth effect on sea cucumber body mass and GI values. Sea cucumbers fed a diet of abalone waste material on the sand substrate exhibited final average GI values of 2.99 % (SE ±0.56). In contrast, sea cucumbers kept in bare tanks and only received abalone waste as food had significantly lower average GI values of 1.36 % (SE±0.2). This suggests that the provision of a sand sustrate in sea cucumber rearing containers is essential for the adequate nutrition and gonadal development. The results of this study indicate that the warty sea cucumber is a promising candidate for inlcusion in an IMTA system with South African perlemoen abalone. , Thesis (MSc) -- Faculty of Science, Ichthyology and Fisheries Science, 2024
- Full Text:
- Date Issued: 2024-10-11
Vertical price transmission of wheat in South Africa
- Authors: Swapi, Asemahle
- Date: 2024-00
- Subjects: Commerce
- Language: English
- Type: Masters theses , text
- Identifier: http://hdl.handle.net/11260/11040 , vital:75880
- Description: The ability of markets to communicate food price signals at different levels of marketing chains is critical to understanding the nature of the competition in the chain, and development of strategies to address challengers of information symmetry and food insecurity. This study examined vertical transmission of wheat price among the main value chain, looking at the pricing behaviour of certain role players in the wheat production/supply and distribution of bread which is a major staple food consumed in South Africa. A nonlinear autoregressive distributed lag model (NARDL) model was used to analyse the yearly time series data for the period of 2000 to 2022. The results of the stationarity test showed that all variables were of order one, I(1). The study used two pairs, namely farmgate price and retail price and farmgate price and wholesale price, to examine the existence of asymmetry between these prices, with rainfall and temperature as control variables. The results indicate the existence of positive long-run asymmetry of 35,9% between farmgate price of wheat and retail price of bread, and 3,49% asymmetry between farmgate price and wholesale price of wheat. In order to develop informed policies on food security, this study suggests that the government should enhance regular access to data and sustain its monitoring and communication of food price information across the whole country. The other thing that is recommended by the study is the provision of subsidies for wheat farmers to help the wheat industry, reduce the cost of bread production, and make bread more affordable and accessible for consumers. , Thesis (Masters) -- Faculty of Economic and Financial Sciences, 2024
- Full Text:
- Date Issued: 2024-00
- Authors: Swapi, Asemahle
- Date: 2024-00
- Subjects: Commerce
- Language: English
- Type: Masters theses , text
- Identifier: http://hdl.handle.net/11260/11040 , vital:75880
- Description: The ability of markets to communicate food price signals at different levels of marketing chains is critical to understanding the nature of the competition in the chain, and development of strategies to address challengers of information symmetry and food insecurity. This study examined vertical transmission of wheat price among the main value chain, looking at the pricing behaviour of certain role players in the wheat production/supply and distribution of bread which is a major staple food consumed in South Africa. A nonlinear autoregressive distributed lag model (NARDL) model was used to analyse the yearly time series data for the period of 2000 to 2022. The results of the stationarity test showed that all variables were of order one, I(1). The study used two pairs, namely farmgate price and retail price and farmgate price and wholesale price, to examine the existence of asymmetry between these prices, with rainfall and temperature as control variables. The results indicate the existence of positive long-run asymmetry of 35,9% between farmgate price of wheat and retail price of bread, and 3,49% asymmetry between farmgate price and wholesale price of wheat. In order to develop informed policies on food security, this study suggests that the government should enhance regular access to data and sustain its monitoring and communication of food price information across the whole country. The other thing that is recommended by the study is the provision of subsidies for wheat farmers to help the wheat industry, reduce the cost of bread production, and make bread more affordable and accessible for consumers. , Thesis (Masters) -- Faculty of Economic and Financial Sciences, 2024
- Full Text:
- Date Issued: 2024-00
Enteric microbial responses to host hyperthermia in southern African insectivorous bats: a test of thermal co-adaptation
- Authors: Hunter, Amy Alison
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424391 , vital:72149
- Description: Embargoed. Expected release date 2025. , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Hunter, Amy Alison
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424391 , vital:72149
- Description: Embargoed. Expected release date 2025. , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2023
- Full Text:
- Date Issued: 2023-10-13
Native-range studies on insect herbivores associated with African Lovegrass (Eragrostis curvula) in South Africa: prospects for biological control in Australia
- Authors: Yell, Liam Dougal
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424446 , vital:72154
- Description: Eragrostis curvula (Schrad.) Nees. (African Lovegrass) is an African native species of grass that was intentionally introduced for pasture in Australia. It has since escaped cultivation and has become widespread and highly invasive. Eragrostis curvula has been recorded in every state and territory in Australia where it has altered fire regimes, disrupted nutrient cycles and can reduce livestock carrying capacity by up to 50%. The Centre for Biological Control at Rhodes University and the New South Wales Department of Primary Industries have been working in collaboration to identify and screen herbivorous insects as biological control agents for E. curvula in Australia. Native-range surveys were conducted between 2021 and 2022 on E. curvula at twenty-two sites across South Africa to identify herbivorous natural enemies associated with it. Species accumulation curves were generated to ensure adequate sampling was performed to identify all the insects associated with E. curvula. Twenty-nine non-target grass species were surveyed simultaneously to determine the field-host range of the natural enemies associated with the target weed. Herbivorous natural enemies were prioritised as possible biological control agents against E. curvula in Australia based on field-host range, predicted efficacy and climatic suitability. Four insect species were consistently found on E. curvula, two of which were herbivorous, as well as a parasitoid and a detritivore. Species accumulation curves show that the insect community was adequately sampled in South Africa. The two herbivorous insects were identified to the lowest taxonomic level using COI barcoding. Both species are undescribed phytophagous wasps in the genus Tetramesa (Hymenoptera: Eurytomidae). Because Tetramesa species have been shown to be host specific and highly damaging in previous biological control programs for other invasive grass weeds, we assessed their suitability as candidate biological control agents for use on E. curvula in Australia. Both Tetramesa species (“sp. 4” and “sp. 5”) were found on several native congeners under field conditions in South Africa. Congeneric South African-native non-target grass species were used as phylogenetic proxies to assess the risk posed to Australian native Eragrostis species. This highlighted three non-target Australian native Eragrostis species, namely: E. parviflora (R. Br.) Trin., E. leptocarpa Benth. fl., and E. trachycarpa Benth., that are at risk of being attacked by the two candidate agents based on their phylogenetic proximity to E. curvula. Predicted efficacy trials were conducted at five long-term repeat survey sites and revealed that Tetramesa sp. 4 does not reduce the probability of E. curvula tiller survival or reproduction, while Tetramesa sp. 5 does not reduce the probability of tiller reproduction but does increase the probability of tiller survival. This result was unexpected and may be a plant compensatory response to herbivory. The sites where both Tetramesa species were collected in South Africa are climatically similar to the invaded range of E. curvula in Australia, and as such, the Tetramesa spp. are likely to be suitably adapted to the climate where they would be released in Australia. These results suggest that both Tetramesa species associated with E. curvula may have too broad a host range to be used as biological control agents in Australia. However, further quarantine-based host-range assessments on Australian native Eragrostis species are recommended to confirm this. The field-based methods used in this study have reduced the number of insect and plant species that host-range assessments will be required to be performed on, thus preventing wasted resources. , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Yell, Liam Dougal
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424446 , vital:72154
- Description: Eragrostis curvula (Schrad.) Nees. (African Lovegrass) is an African native species of grass that was intentionally introduced for pasture in Australia. It has since escaped cultivation and has become widespread and highly invasive. Eragrostis curvula has been recorded in every state and territory in Australia where it has altered fire regimes, disrupted nutrient cycles and can reduce livestock carrying capacity by up to 50%. The Centre for Biological Control at Rhodes University and the New South Wales Department of Primary Industries have been working in collaboration to identify and screen herbivorous insects as biological control agents for E. curvula in Australia. Native-range surveys were conducted between 2021 and 2022 on E. curvula at twenty-two sites across South Africa to identify herbivorous natural enemies associated with it. Species accumulation curves were generated to ensure adequate sampling was performed to identify all the insects associated with E. curvula. Twenty-nine non-target grass species were surveyed simultaneously to determine the field-host range of the natural enemies associated with the target weed. Herbivorous natural enemies were prioritised as possible biological control agents against E. curvula in Australia based on field-host range, predicted efficacy and climatic suitability. Four insect species were consistently found on E. curvula, two of which were herbivorous, as well as a parasitoid and a detritivore. Species accumulation curves show that the insect community was adequately sampled in South Africa. The two herbivorous insects were identified to the lowest taxonomic level using COI barcoding. Both species are undescribed phytophagous wasps in the genus Tetramesa (Hymenoptera: Eurytomidae). Because Tetramesa species have been shown to be host specific and highly damaging in previous biological control programs for other invasive grass weeds, we assessed their suitability as candidate biological control agents for use on E. curvula in Australia. Both Tetramesa species (“sp. 4” and “sp. 5”) were found on several native congeners under field conditions in South Africa. Congeneric South African-native non-target grass species were used as phylogenetic proxies to assess the risk posed to Australian native Eragrostis species. This highlighted three non-target Australian native Eragrostis species, namely: E. parviflora (R. Br.) Trin., E. leptocarpa Benth. fl., and E. trachycarpa Benth., that are at risk of being attacked by the two candidate agents based on their phylogenetic proximity to E. curvula. Predicted efficacy trials were conducted at five long-term repeat survey sites and revealed that Tetramesa sp. 4 does not reduce the probability of E. curvula tiller survival or reproduction, while Tetramesa sp. 5 does not reduce the probability of tiller reproduction but does increase the probability of tiller survival. This result was unexpected and may be a plant compensatory response to herbivory. The sites where both Tetramesa species were collected in South Africa are climatically similar to the invaded range of E. curvula in Australia, and as such, the Tetramesa spp. are likely to be suitably adapted to the climate where they would be released in Australia. These results suggest that both Tetramesa species associated with E. curvula may have too broad a host range to be used as biological control agents in Australia. However, further quarantine-based host-range assessments on Australian native Eragrostis species are recommended to confirm this. The field-based methods used in this study have reduced the number of insect and plant species that host-range assessments will be required to be performed on, thus preventing wasted resources. , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2023
- Full Text:
- Date Issued: 2023-10-13
The effect of piospheres on the ecology of insectivorous birds and their arthropod prey
- Authors: Balmer, Natasha Louise
- Date: 2023-10-13
- Subjects: Desertification South Africa Eastern Cape , Environmental degradation , Arid regions ecology , Insectivores , Arthropoda , Birds Food , Plants Effect of grazing on South Africa Eastern Cape
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424380 , vital:72148
- Description: Desertification is the degradation of arid ecosystems that result in the loss of biodiversity. Piospheres are areas of local degradation around a central point due to overgrazing and increased herbivore presence. There is a paucity of information regarding the effect of localised degradation on arthropods and insectivorous birds. Both of these organisms play crucial roles in ecosystem functioning and stability and can be used as models to study ecosystem functioning. I investigated the effect of piospheres on arthropods and birds in the Eastern Cape province of South Africa. I found that the abundance and diversity of arthropods were significantly reduced inside the piospheres due to the lack of vegetation. Termites were a group specifically negatively impacted by piospheres, with a significant reduction in their presence inside the piosphere. The family composition of arthropods also changed inside and outside the piospheres, with Caelifera, Diptera and Formicidae being the most dominant groups. The diversity of birds was also significantly reduced due to the degradation inside the piospheres. Looking at insectivorous birds, I found that the reduction in both vegetation and arthropod prey availability resulted in non-random avoidance of piospheres. This shows that piospheres negatively impact both arthropods and birds. The results from my study are supported by other literature studying the effects of habitat degradation associated with desertification. Due to the similarities of degradation between piospheres and desertification I make the argument that piospheres can be studied as localised models of desertification. The decrease in vegetation and arthropod abundance and diversity was found to further impact the feeding success of insectivorous birds. Using piospheres as a model for desertification, I found that the foraging effort of birds is significantly reduced within a degraded area due to the lack of vegetation providing safety to arthropod prey species. In addition to this, the foraging efficiency of insectivorous birds is significantly reduced inside the piospheres due to the decreased arthropod abundance and diversity. This shows that inside the piospheres birds spend less time searching for insects and have fewer successful feeds. This has implications for desertification of arid environments where birds face hyperthermia. , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Balmer, Natasha Louise
- Date: 2023-10-13
- Subjects: Desertification South Africa Eastern Cape , Environmental degradation , Arid regions ecology , Insectivores , Arthropoda , Birds Food , Plants Effect of grazing on South Africa Eastern Cape
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424380 , vital:72148
- Description: Desertification is the degradation of arid ecosystems that result in the loss of biodiversity. Piospheres are areas of local degradation around a central point due to overgrazing and increased herbivore presence. There is a paucity of information regarding the effect of localised degradation on arthropods and insectivorous birds. Both of these organisms play crucial roles in ecosystem functioning and stability and can be used as models to study ecosystem functioning. I investigated the effect of piospheres on arthropods and birds in the Eastern Cape province of South Africa. I found that the abundance and diversity of arthropods were significantly reduced inside the piospheres due to the lack of vegetation. Termites were a group specifically negatively impacted by piospheres, with a significant reduction in their presence inside the piosphere. The family composition of arthropods also changed inside and outside the piospheres, with Caelifera, Diptera and Formicidae being the most dominant groups. The diversity of birds was also significantly reduced due to the degradation inside the piospheres. Looking at insectivorous birds, I found that the reduction in both vegetation and arthropod prey availability resulted in non-random avoidance of piospheres. This shows that piospheres negatively impact both arthropods and birds. The results from my study are supported by other literature studying the effects of habitat degradation associated with desertification. Due to the similarities of degradation between piospheres and desertification I make the argument that piospheres can be studied as localised models of desertification. The decrease in vegetation and arthropod abundance and diversity was found to further impact the feeding success of insectivorous birds. Using piospheres as a model for desertification, I found that the foraging effort of birds is significantly reduced within a degraded area due to the lack of vegetation providing safety to arthropod prey species. In addition to this, the foraging efficiency of insectivorous birds is significantly reduced inside the piospheres due to the decreased arthropod abundance and diversity. This shows that inside the piospheres birds spend less time searching for insects and have fewer successful feeds. This has implications for desertification of arid environments where birds face hyperthermia. , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2023
- Full Text:
- Date Issued: 2023-10-13
Students'perspectives of quality educationat a selected South African University
- Authors: Nkalane, Unathi Juliet
- Date: 2023-00
- Subjects: Quality Education
- Language: English
- Type: Masters theses , text
- Identifier: http://hdl.handle.net/11260/11144 , vital:75924
- Description: Quality education is a critical component of higher education institutions in South Africa. This study aims to explore students' perspectives on quality education at a South African higher education institution. The study utilized a qualitative research approach, with semi-structured interviews and observation, conducted with ten undergraduate students and two lecturers from the Technology and Mathematics Education (TME) department, student affairs, the quality assurance office, and Department of Learning and Teaching (DLT). The findings highlight the importance of effective communication, adequate resources, and supportive learning environments. The study also identified challenges such as limited access to resources, inadequate academic support, and insufficient feedback. The study's results suggest that student perspectives on quality education are multifaceted and require attention from higher education institutions to improve the quality of education and enhance student satisfaction. Keywords: Quality education, Student’s perspectives, Higher Education Institution, Resources. , Thesis (Masters) -- Faculty of Education, 2023
- Full Text:
- Date Issued: 2023-00
- Authors: Nkalane, Unathi Juliet
- Date: 2023-00
- Subjects: Quality Education
- Language: English
- Type: Masters theses , text
- Identifier: http://hdl.handle.net/11260/11144 , vital:75924
- Description: Quality education is a critical component of higher education institutions in South Africa. This study aims to explore students' perspectives on quality education at a South African higher education institution. The study utilized a qualitative research approach, with semi-structured interviews and observation, conducted with ten undergraduate students and two lecturers from the Technology and Mathematics Education (TME) department, student affairs, the quality assurance office, and Department of Learning and Teaching (DLT). The findings highlight the importance of effective communication, adequate resources, and supportive learning environments. The study also identified challenges such as limited access to resources, inadequate academic support, and insufficient feedback. The study's results suggest that student perspectives on quality education are multifaceted and require attention from higher education institutions to improve the quality of education and enhance student satisfaction. Keywords: Quality education, Student’s perspectives, Higher Education Institution, Resources. , Thesis (Masters) -- Faculty of Education, 2023
- Full Text:
- Date Issued: 2023-00
Refining predator-prey preference at the prey demographic level for cheetah and lion
- Authors: Annear, Eleesha
- Date: 2022-04
- Subjects: Social behavior in animals --South Africa , Predatory animals –Behavior
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/55800 , vital:53880
- Description: Traditional prey preference models estimate prey preference using a coarse species-specific body mass of three-quarters of the mean adult female body mass. This is widely assumed to estimate the average mass across prey populations, accounting for neonates, juveniles, sub-adults, and adults. However, this approach negates the models’ ability to predict demography-specific prey preferences, thus reducing our ability to predict the impacts of predation on prey populations. The objectives of this study were to 1) refine the prey selection models, using lion Panthera leo and cheetah Acinonyx jubatus as model species, by incorporating prey demographic classes and season and, 2) determine the influence of seasonal variability in availability of these prey demographic classes on cheetah reproduction. Lions preferentially killed adults of larger species (e.g., wildebeest, waterbuck, and zebra) irrespective of the season, as predicted by optimal foraging theory. Sub-adult, juvenile, and neonate prey were killed by lions relative to their abundance. Cheetahs preferred juvenile prey of large species, namely kudu, zebra, and wildebeest. Season influenced cheetah preference with neonates and juveniles being preferred during the wet season and adults of smaller species, and juveniles of larger species being preferred during the dry season. Thus, results support the alternative demographic class hypothesis. Furthermore, the availability of neonate and juvenile prey drives cheetah reproduction patterns with conception and cub independence coinciding with the peak availability of easy-to-catch neonates. Lactation coincided with the high availability of relatively larger juveniles to ensure that females obtain enough resources to sustain the most energetically costly reproductive phase. In addition, I suggest cheetah may be particularly vulnerable to disturbances that impact on prey reproduction (e.g., drought, fire, and flood), given their reliance on neonate and juvenile prey. My findings highlight that estimating species-level prey preference using a coarse species-specific body mass masks the level of prey use and potential preferences for the different prey demographic classes. The use of some prey species may be largely confined to juveniles by smaller predators, meaning that prey availability would vary seasonally, may influence reproductive patterns, and carrying capacity models would need to be revised in terms of the available demographic-specific prey biomass. , Thesis (MSc) -- Faculty of Sciences, School of Environmental Sciences, 2022
- Full Text:
- Date Issued: 2022-04
- Authors: Annear, Eleesha
- Date: 2022-04
- Subjects: Social behavior in animals --South Africa , Predatory animals –Behavior
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/55800 , vital:53880
- Description: Traditional prey preference models estimate prey preference using a coarse species-specific body mass of three-quarters of the mean adult female body mass. This is widely assumed to estimate the average mass across prey populations, accounting for neonates, juveniles, sub-adults, and adults. However, this approach negates the models’ ability to predict demography-specific prey preferences, thus reducing our ability to predict the impacts of predation on prey populations. The objectives of this study were to 1) refine the prey selection models, using lion Panthera leo and cheetah Acinonyx jubatus as model species, by incorporating prey demographic classes and season and, 2) determine the influence of seasonal variability in availability of these prey demographic classes on cheetah reproduction. Lions preferentially killed adults of larger species (e.g., wildebeest, waterbuck, and zebra) irrespective of the season, as predicted by optimal foraging theory. Sub-adult, juvenile, and neonate prey were killed by lions relative to their abundance. Cheetahs preferred juvenile prey of large species, namely kudu, zebra, and wildebeest. Season influenced cheetah preference with neonates and juveniles being preferred during the wet season and adults of smaller species, and juveniles of larger species being preferred during the dry season. Thus, results support the alternative demographic class hypothesis. Furthermore, the availability of neonate and juvenile prey drives cheetah reproduction patterns with conception and cub independence coinciding with the peak availability of easy-to-catch neonates. Lactation coincided with the high availability of relatively larger juveniles to ensure that females obtain enough resources to sustain the most energetically costly reproductive phase. In addition, I suggest cheetah may be particularly vulnerable to disturbances that impact on prey reproduction (e.g., drought, fire, and flood), given their reliance on neonate and juvenile prey. My findings highlight that estimating species-level prey preference using a coarse species-specific body mass masks the level of prey use and potential preferences for the different prey demographic classes. The use of some prey species may be largely confined to juveniles by smaller predators, meaning that prey availability would vary seasonally, may influence reproductive patterns, and carrying capacity models would need to be revised in terms of the available demographic-specific prey biomass. , Thesis (MSc) -- Faculty of Sciences, School of Environmental Sciences, 2022
- Full Text:
- Date Issued: 2022-04
Plastic particle characterization and concentrations found in the river and marine water environment of Algoa Bay, South Africa
- Authors: Moss, Kerry-Leigh
- Date: 2021-12
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/53874 , vital:46025
- Description: Only 12% of the world's published plastic research includes references to Africa despite it being a significant contributor to the global plastic waste and mismanagement problem (~88.5% of Africa's plastic waste is mismanaged). Ocean plastics are transported from land by rivers to the sea. However, source contextualization is complex. Many African rivers predominantly run alongside human settlements that host informal waste dumpsites. In this study a simple cost effective, easily deployed, consistent and replicable survey methodology was employed. The study quantified macro plastic in three rivers discharging into Algoa Bay, South Africa. The results indicated that industrial Swartkops and metropolitan Baakens Rivers both illustrate moderate plastic pollution (>3000 plastic particles/day), with the relatively natural Sundays River to showing minimal evidence of river macroplastic (<100 plastic particles/day). The types of plastic were noted using the RIMMEL app (premier African implementation), enabling proportional comparison of different plastic litter types to be completed. , Thesis (MSc) -- Faculty of Science, Oceanography Department,2021
- Full Text:
- Date Issued: 2021-12
- Authors: Moss, Kerry-Leigh
- Date: 2021-12
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/53874 , vital:46025
- Description: Only 12% of the world's published plastic research includes references to Africa despite it being a significant contributor to the global plastic waste and mismanagement problem (~88.5% of Africa's plastic waste is mismanaged). Ocean plastics are transported from land by rivers to the sea. However, source contextualization is complex. Many African rivers predominantly run alongside human settlements that host informal waste dumpsites. In this study a simple cost effective, easily deployed, consistent and replicable survey methodology was employed. The study quantified macro plastic in three rivers discharging into Algoa Bay, South Africa. The results indicated that industrial Swartkops and metropolitan Baakens Rivers both illustrate moderate plastic pollution (>3000 plastic particles/day), with the relatively natural Sundays River to showing minimal evidence of river macroplastic (<100 plastic particles/day). The types of plastic were noted using the RIMMEL app (premier African implementation), enabling proportional comparison of different plastic litter types to be completed. , Thesis (MSc) -- Faculty of Science, Oceanography Department,2021
- Full Text:
- Date Issued: 2021-12
Plastic particle characterization and concentrations found in the river and marine water environment of Algoa Bay, South Africa
- Authors: Moss, Kerry-Leigh
- Date: 2021-12
- Subjects: Marine pollution , Plastic marine debris --Environmental aspects , Algoa Bay -- Eastern Cape
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/55645 , vital:53403
- Description: With just 4% of published plastic pollution research, the African region remains one of the most poorly 221 understood areas, leaving a large knowledge gap in our understanding of this global pollution problem 222 (Hurley, Woodward, & Rothwell, 2018). It is estimated that 64 to 90% of the ocean’s plastics originate 223 from fluxes in the terrestrial environment, however determining the exact source is not a simple task 224 (Andrady, 2011; Hurley et al., 2018). Plastic items, including the biodegradable plastic items, 225 breakdown in the marine environment through mechanical action resulting in non-degradable 226 microscopic fragments of synthetic polymers (Thompson et al., 2004). However, the consequences of 227 these microplastic fragments.This research intends to address two aims; first, to provide an estimation of the quantity of plastic 235 transportation via African rivers to the greater body of knowledge of global plastic emissions. This aim 236 will specifically focus on determining plastic output via Port Elizabeth rivers into the Algoa Bay marine 237 environment. The second aim of this research is to quantify and characterize the amount of microplastic 238 in the marine environment of Algoa Bay. The second aim will focus on identifying microplastic (MP) 239 throughout the water column. 240 This research consists of six objectives; first, to identify, design and field test a cost-effective system for 241 monitoring macroplastic quantity output from riverine to marine environments. Second, to contribute to 242 the body of knowledge of African river plastic pollution through quantification and characterisation of 243 macroplastics in the Port Elizabeth rivers. Third, to compare three very different rivers with different 244 levels of urbanisation (industrial, urban, and remote) to ascertain the impact of population and 245 government pollution management protocols on plastic emissions. Fourth, to measure microplastic 246 quantities at three depths from eight locations across the marine environment of Algoa Bay. Fifth, quantitatively characterize the microplastics in Algoa Bay to highlight any patterns of distribution. Sixth, 248 to compare the Algoa Bay concentrations with published international marine microplastic findings. , Thesis (MSc) -- Faculty of Science, Ocean Science, 2021
- Full Text:
- Date Issued: 2021-12
- Authors: Moss, Kerry-Leigh
- Date: 2021-12
- Subjects: Marine pollution , Plastic marine debris --Environmental aspects , Algoa Bay -- Eastern Cape
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/55645 , vital:53403
- Description: With just 4% of published plastic pollution research, the African region remains one of the most poorly 221 understood areas, leaving a large knowledge gap in our understanding of this global pollution problem 222 (Hurley, Woodward, & Rothwell, 2018). It is estimated that 64 to 90% of the ocean’s plastics originate 223 from fluxes in the terrestrial environment, however determining the exact source is not a simple task 224 (Andrady, 2011; Hurley et al., 2018). Plastic items, including the biodegradable plastic items, 225 breakdown in the marine environment through mechanical action resulting in non-degradable 226 microscopic fragments of synthetic polymers (Thompson et al., 2004). However, the consequences of 227 these microplastic fragments.This research intends to address two aims; first, to provide an estimation of the quantity of plastic 235 transportation via African rivers to the greater body of knowledge of global plastic emissions. This aim 236 will specifically focus on determining plastic output via Port Elizabeth rivers into the Algoa Bay marine 237 environment. The second aim of this research is to quantify and characterize the amount of microplastic 238 in the marine environment of Algoa Bay. The second aim will focus on identifying microplastic (MP) 239 throughout the water column. 240 This research consists of six objectives; first, to identify, design and field test a cost-effective system for 241 monitoring macroplastic quantity output from riverine to marine environments. Second, to contribute to 242 the body of knowledge of African river plastic pollution through quantification and characterisation of 243 macroplastics in the Port Elizabeth rivers. Third, to compare three very different rivers with different 244 levels of urbanisation (industrial, urban, and remote) to ascertain the impact of population and 245 government pollution management protocols on plastic emissions. Fourth, to measure microplastic 246 quantities at three depths from eight locations across the marine environment of Algoa Bay. Fifth, quantitatively characterize the microplastics in Algoa Bay to highlight any patterns of distribution. Sixth, 248 to compare the Algoa Bay concentrations with published international marine microplastic findings. , Thesis (MSc) -- Faculty of Science, Ocean Science, 2021
- Full Text:
- Date Issued: 2021-12
Media consumption and identity formation: the consumption of Latin American telenovelas in two neighbourhoods of Maputo in Mozambique
- Authors: Ofumane, Alvo Naftal
- Date: 2021-10-29
- Subjects: Television soap operas Mozambique Maputo , Identity (Psychology) and mass media Mozambique Maputo , Television soap operas History and criticism , Visual reception theory Mozambique Maputo , Mozambique Politics and government , Mozambique Social conditions , Mozambique Social life and customs
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/192287 , vital:45212
- Description: This study explores how the residents of two neighbourhoods in Maputo, KaMaxakeni and KaMpfumo interact with and make meanings of (Latin American) telenovelas, as part of their identity formation process. It is guided by questions on how the residents of these two neighbourhoods interact with telenovelas in their daily lives; how this shapes their own values and understanding of themselves and the world in which they live; what aspects of telenovelas they value, and what meanings they make from them; and, finally, what determines their choices of media consumption. The study adopted reception theory, rooted in qualitative methodology. This approach explores the ‘insider’s’ perspective of the research subjects, taking the actors’ perspective as the empirical point of departure. Using a purposive theoretical sampling procedure, targeting those families who are avid viewers of telenovelas, the data were generated through participant observation, focus groups discussions, and individual interviews. To understand and interpret the interface between the telenovela (medium) and its viewers (audience) in Maputo, the study used qualitative thematic content analysis of the telenovelas viewing process by the residents of KaMpfumo and KaMaxakeni. The data show that the residents of KaMpfumo and KaMaxakeni in Maputo interact and make sense of the telenovelas in various ways. Telenovelas are used as an educational tool; they are used to reinforce daily life world practices; they s shape people’s personal character; they become another family presence; they are used to build or strengthen physical and virtual viewing networks, and, “Pure” telenovela viewing is a relatively rare occurrence. , Thesis (MA) -- Faculty of Humanities, Journalism and Media Studies, 2021
- Full Text:
- Date Issued: 2021-10-29
- Authors: Ofumane, Alvo Naftal
- Date: 2021-10-29
- Subjects: Television soap operas Mozambique Maputo , Identity (Psychology) and mass media Mozambique Maputo , Television soap operas History and criticism , Visual reception theory Mozambique Maputo , Mozambique Politics and government , Mozambique Social conditions , Mozambique Social life and customs
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/192287 , vital:45212
- Description: This study explores how the residents of two neighbourhoods in Maputo, KaMaxakeni and KaMpfumo interact with and make meanings of (Latin American) telenovelas, as part of their identity formation process. It is guided by questions on how the residents of these two neighbourhoods interact with telenovelas in their daily lives; how this shapes their own values and understanding of themselves and the world in which they live; what aspects of telenovelas they value, and what meanings they make from them; and, finally, what determines their choices of media consumption. The study adopted reception theory, rooted in qualitative methodology. This approach explores the ‘insider’s’ perspective of the research subjects, taking the actors’ perspective as the empirical point of departure. Using a purposive theoretical sampling procedure, targeting those families who are avid viewers of telenovelas, the data were generated through participant observation, focus groups discussions, and individual interviews. To understand and interpret the interface between the telenovela (medium) and its viewers (audience) in Maputo, the study used qualitative thematic content analysis of the telenovelas viewing process by the residents of KaMpfumo and KaMaxakeni. The data show that the residents of KaMpfumo and KaMaxakeni in Maputo interact and make sense of the telenovelas in various ways. Telenovelas are used as an educational tool; they are used to reinforce daily life world practices; they s shape people’s personal character; they become another family presence; they are used to build or strengthen physical and virtual viewing networks, and, “Pure” telenovela viewing is a relatively rare occurrence. , Thesis (MA) -- Faculty of Humanities, Journalism and Media Studies, 2021
- Full Text:
- Date Issued: 2021-10-29
Factors contributing to employee engagement in an aquaculture organisation in the Eastern Cape
- Authors: Clark, Gesina Maria
- Date: 2021-04
- Subjects: Management -- Employee participation , Employee motivation , Personnel management
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/51084 , vital:43207
- Description: The concept of work engagement has become increasingly important in modern day organisations due to the impact of engagement on productivity, absenteeism, retention and general employee well-being. Organisations with the ability to nurture and improve the engagement levels of their employees are able to prosper as sustainable, competitive and adaptive organisations. The aim of this research is to determine which factors influence engagement of employees in South Africa and specifically in the aquaculture arena, which predominantly employs unskilled and semi-skilled people. A quantitative research design was applied to determine the work engagement levels of employees in an aquaculture organisation in the Eastern Cape, South Africa. Participants were requested to complete the Utrecht Work Engagement Scale as well as a biographic questionnaire. Engagement levels of different biographic groups were compared. Results indicate that there is a statistical and practical significant difference in the engagement levels of employees from different biographic groups. Older employees and employees with tertiary qualifications reported higher engagement levels. Female employees also indicated significantly higher engagement levels than their male colleagues. There are significant differences in the engagement levels of employees from different work sections and different lengths of service. Many of the differences in engagement levels can be explained in terms of the Job Demands-Resources Model. The difference in engagement level between respondents from different work sections may be due to differences in leadership style of the section supervisors. The scope of this study is not sufficient to explain the reasons for differences and more research in this area is recommended. The diverse employment landscape in South Africa requires more than a “one-size fits all” approach to managing employee engagement. This research adds to the body of existing literature on engagement in the South African labour landscape and provides valuable information to organisational leaders and Human Resource Managers when planning employee engagement initiatives. , Thesis (MBA) -- Faculty of Business and Economic Sciences, Business Administration, 2021
- Full Text:
- Date Issued: 2021-04
- Authors: Clark, Gesina Maria
- Date: 2021-04
- Subjects: Management -- Employee participation , Employee motivation , Personnel management
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/51084 , vital:43207
- Description: The concept of work engagement has become increasingly important in modern day organisations due to the impact of engagement on productivity, absenteeism, retention and general employee well-being. Organisations with the ability to nurture and improve the engagement levels of their employees are able to prosper as sustainable, competitive and adaptive organisations. The aim of this research is to determine which factors influence engagement of employees in South Africa and specifically in the aquaculture arena, which predominantly employs unskilled and semi-skilled people. A quantitative research design was applied to determine the work engagement levels of employees in an aquaculture organisation in the Eastern Cape, South Africa. Participants were requested to complete the Utrecht Work Engagement Scale as well as a biographic questionnaire. Engagement levels of different biographic groups were compared. Results indicate that there is a statistical and practical significant difference in the engagement levels of employees from different biographic groups. Older employees and employees with tertiary qualifications reported higher engagement levels. Female employees also indicated significantly higher engagement levels than their male colleagues. There are significant differences in the engagement levels of employees from different work sections and different lengths of service. Many of the differences in engagement levels can be explained in terms of the Job Demands-Resources Model. The difference in engagement level between respondents from different work sections may be due to differences in leadership style of the section supervisors. The scope of this study is not sufficient to explain the reasons for differences and more research in this area is recommended. The diverse employment landscape in South Africa requires more than a “one-size fits all” approach to managing employee engagement. This research adds to the body of existing literature on engagement in the South African labour landscape and provides valuable information to organisational leaders and Human Resource Managers when planning employee engagement initiatives. , Thesis (MBA) -- Faculty of Business and Economic Sciences, Business Administration, 2021
- Full Text:
- Date Issued: 2021-04
Inhibitor search and variant analysis of Acetylcholinesterase
- Authors: Ras, Harnaud
- Date: 2021-04
- Subjects: Acetylcholinesterase , Alzheimer's disease , Acetylcholinesterase -- Inhibitors , Alzheimer's disease -- Chemotherapy , Cerebrovascular disease -- Treatment , Molecular mechanics Poisson–Boltzmann surface area (MM-PBSA)
- Language: English
- Type: thesis , text , Masters , MSc
- Identifier: http://hdl.handle.net/10962/178191 , vital:42919
- Description: Acetylcholinesterase (AChE) inhibition is used to treat Alzheimer's disease by increasing the availability of acetylcholine to carry nerve signals in the brain. The response to this treatment varies widely, which may be due to altered affnity to the current drugs caused by genetic variation. Various negative side-effects limit their use. As this is one of the only available therapeutic drug targets to treat Alzheimer's disease, decreasing the negative effects is of great importance. AChE is involved in biological processes that occur after acute ischemic stroke. Stroke is the third leading cause of death worldwide, and 87% of all stroke cases belong to ischemic stroke. AchEI (cholinesterase inhibitors) have been suggested to have properties that lower the risk of stroke. AChE is one of 15 verified drug targets under study for treatment of stroke. In addition to Alzheimer's disease and stroke, Lewy body disease (LBD) may be treated using cholinesterase inhibitors. The goals of this study are to find inhibitors that can potentially be used to treat Alzheimer's disease and/or stroke and to investigate variants which may affect protein dynamics and function. Two variants were analyzed, P247L and T229S. Molecular simulation of the P247L variant resulted in a disruption in protein dynamics in comparison to the wildtype. A total of 5728 molecules were screened and 10 nanosecond simulations were used to narrow down the set of compounds. The four best performing molecules were simulated for 10 nanoseconds. MM-PBSA was performed to identify molecules with high binding free energies. , Thesis (MSc) -- Faculty of Science, Biochemistry and Microbiology, 2021
- Full Text:
- Date Issued: 2021-04
- Authors: Ras, Harnaud
- Date: 2021-04
- Subjects: Acetylcholinesterase , Alzheimer's disease , Acetylcholinesterase -- Inhibitors , Alzheimer's disease -- Chemotherapy , Cerebrovascular disease -- Treatment , Molecular mechanics Poisson–Boltzmann surface area (MM-PBSA)
- Language: English
- Type: thesis , text , Masters , MSc
- Identifier: http://hdl.handle.net/10962/178191 , vital:42919
- Description: Acetylcholinesterase (AChE) inhibition is used to treat Alzheimer's disease by increasing the availability of acetylcholine to carry nerve signals in the brain. The response to this treatment varies widely, which may be due to altered affnity to the current drugs caused by genetic variation. Various negative side-effects limit their use. As this is one of the only available therapeutic drug targets to treat Alzheimer's disease, decreasing the negative effects is of great importance. AChE is involved in biological processes that occur after acute ischemic stroke. Stroke is the third leading cause of death worldwide, and 87% of all stroke cases belong to ischemic stroke. AchEI (cholinesterase inhibitors) have been suggested to have properties that lower the risk of stroke. AChE is one of 15 verified drug targets under study for treatment of stroke. In addition to Alzheimer's disease and stroke, Lewy body disease (LBD) may be treated using cholinesterase inhibitors. The goals of this study are to find inhibitors that can potentially be used to treat Alzheimer's disease and/or stroke and to investigate variants which may affect protein dynamics and function. Two variants were analyzed, P247L and T229S. Molecular simulation of the P247L variant resulted in a disruption in protein dynamics in comparison to the wildtype. A total of 5728 molecules were screened and 10 nanosecond simulations were used to narrow down the set of compounds. The four best performing molecules were simulated for 10 nanoseconds. MM-PBSA was performed to identify molecules with high binding free energies. , Thesis (MSc) -- Faculty of Science, Biochemistry and Microbiology, 2021
- Full Text:
- Date Issued: 2021-04
Effect of Mucuna pruriens based-diets on fatty acids composition and sensory attributes of meat from broiler chickens
- Authors: Makhamba, Nasiphi
- Date: 2020-11
- Subjects: Fatty acids , Broilers (Chickens)
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/20771 , vital:46554
- Description: The current study was conducted to determine the effect of feeding different inclusion levels of processed Mucuna pruriens on fatty acid composition and sensory attributes of broiler chickens. 120 Cob500 broilers were used in the experiment. The experiment was divided into 4 treatment (0, 10, 15 and 20 percent of Mucuna pruriens) groups, each treatment with 6 replicates (5 birds per replicate) in a completely randomized design. The first treatment (0 percent) was used as control against the three different levels of Mucuna pruriens. The birds were reared in a deep litter system until they reached slaughter weight of 2kg. At day 42 a total of 80 birds were slaughtered and breast muscles were sampled for the evaluation of sensory attributes and fatty acid composition. For sensory evaluation meat samples were prepared and boiled at 80°C until the internal temperature reached 82°C, 40 consumers were used to assess the meat samples and give scores according to 9-point hedonic scale. The fatty acid content was determined and recorded using the gas chromatography. Total saturated fatty acid (SFA), total monounsaturated fatty acid (MUFA), and total polyunsaturated fatty acid (PUFA) of the breast meat were not affected by diets. Omega-6 and omega-3 fatty acid were also not influenced by treatment diets. However, breast muscle from broilers fed 20 percent Mucuna pruriens seed meal inclusion had lower Myristic acid. The sensory attributes; aroma, colour, flavour, juiciness, tenderness and acceptability were assessed, dietary treatments affected the juiciness, tenderness and acceptability of meat, the treatments showed no significant difference on colour, aroma and flavour. Different age groups accepted the meat differently, the respondents that were between 18 and 22 years old gave the highest scores to the acceptability of meat than the other age groups, and different age groups also gave different scores in the aroma of meat. Females and males accepted the meat differently, the female respondents gave higher scores on the flavour of meat than males. Different inclusion levels of Mucuna pruriens positively affected fatty acid composition and sensory attributes of broiler chickens without causing any detrimental effects. , Thesis (MSc) (Animal Science) -- University of Fort Hare, 2021
- Full Text:
- Date Issued: 2020-11
- Authors: Makhamba, Nasiphi
- Date: 2020-11
- Subjects: Fatty acids , Broilers (Chickens)
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/20771 , vital:46554
- Description: The current study was conducted to determine the effect of feeding different inclusion levels of processed Mucuna pruriens on fatty acid composition and sensory attributes of broiler chickens. 120 Cob500 broilers were used in the experiment. The experiment was divided into 4 treatment (0, 10, 15 and 20 percent of Mucuna pruriens) groups, each treatment with 6 replicates (5 birds per replicate) in a completely randomized design. The first treatment (0 percent) was used as control against the three different levels of Mucuna pruriens. The birds were reared in a deep litter system until they reached slaughter weight of 2kg. At day 42 a total of 80 birds were slaughtered and breast muscles were sampled for the evaluation of sensory attributes and fatty acid composition. For sensory evaluation meat samples were prepared and boiled at 80°C until the internal temperature reached 82°C, 40 consumers were used to assess the meat samples and give scores according to 9-point hedonic scale. The fatty acid content was determined and recorded using the gas chromatography. Total saturated fatty acid (SFA), total monounsaturated fatty acid (MUFA), and total polyunsaturated fatty acid (PUFA) of the breast meat were not affected by diets. Omega-6 and omega-3 fatty acid were also not influenced by treatment diets. However, breast muscle from broilers fed 20 percent Mucuna pruriens seed meal inclusion had lower Myristic acid. The sensory attributes; aroma, colour, flavour, juiciness, tenderness and acceptability were assessed, dietary treatments affected the juiciness, tenderness and acceptability of meat, the treatments showed no significant difference on colour, aroma and flavour. Different age groups accepted the meat differently, the respondents that were between 18 and 22 years old gave the highest scores to the acceptability of meat than the other age groups, and different age groups also gave different scores in the aroma of meat. Females and males accepted the meat differently, the female respondents gave higher scores on the flavour of meat than males. Different inclusion levels of Mucuna pruriens positively affected fatty acid composition and sensory attributes of broiler chickens without causing any detrimental effects. , Thesis (MSc) (Animal Science) -- University of Fort Hare, 2021
- Full Text:
- Date Issued: 2020-11
Expressions of “Local” and “Global” Identity: The Design of an International Convention Centre for Port Elizabeth
- Authors: Pretorius, Hanri
- Date: 2020-09
- Subjects: Convention facilities -- Port Elizabeth , Architecture -- Designs and plans
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/59128 , vital:60266
- Description: Convention centres are highly flexible business and leisure gathering spaces where memorable experiences happen indoors. These centres are usually surrounded by perfectly manicured landscaping, strategically placed hotels in the immediate area, and an abundance of fashionable restaurants aimed at creating a lifestyle experience that will ensure that clients return. This convention centre experience can be found in almost every city that has a convention centre. These centres’ designs have become universal and their focus is aimed at outdoing one another to create a more iconic building to attract more people and host more events. This design treatise will focus on how to localise convention centre design to create a place for not only indoor experiences but outdoor experiences as well, to create a multifaceted design that will cater for convention centre activities as well as for its surrounding community, thus ensuring the creation of an urban catalyst that promotes the creation of a vibrant public gathering space. The research and process to achieve this is thus documented. The document consists of two distinct parts. The first part provides insight into the theoretical position taken which provides a lens through which all other research is viewed. The second comprises the design process rooted within the theoretical position that was established in Part 1. Together, the research as well as the design process will lead to a refined design outcome presented as a set of architectural drawings and a computerised model. , Thesis (MA) -- Faculty of Engineering, the Built Environment, and Technology, 2020
- Full Text:
- Date Issued: 2020-09
- Authors: Pretorius, Hanri
- Date: 2020-09
- Subjects: Convention facilities -- Port Elizabeth , Architecture -- Designs and plans
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/59128 , vital:60266
- Description: Convention centres are highly flexible business and leisure gathering spaces where memorable experiences happen indoors. These centres are usually surrounded by perfectly manicured landscaping, strategically placed hotels in the immediate area, and an abundance of fashionable restaurants aimed at creating a lifestyle experience that will ensure that clients return. This convention centre experience can be found in almost every city that has a convention centre. These centres’ designs have become universal and their focus is aimed at outdoing one another to create a more iconic building to attract more people and host more events. This design treatise will focus on how to localise convention centre design to create a place for not only indoor experiences but outdoor experiences as well, to create a multifaceted design that will cater for convention centre activities as well as for its surrounding community, thus ensuring the creation of an urban catalyst that promotes the creation of a vibrant public gathering space. The research and process to achieve this is thus documented. The document consists of two distinct parts. The first part provides insight into the theoretical position taken which provides a lens through which all other research is viewed. The second comprises the design process rooted within the theoretical position that was established in Part 1. Together, the research as well as the design process will lead to a refined design outcome presented as a set of architectural drawings and a computerised model. , Thesis (MA) -- Faculty of Engineering, the Built Environment, and Technology, 2020
- Full Text:
- Date Issued: 2020-09
Chemical evaluation, in vitro ruminal dry matter (DM) degradability and ruminal biological activity of common browse tree fruits of Alice
- Authors: Sondzaba, Bavuyise
- Date: 2020-01
- Subjects: Ruminants
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/20882 , vital:46695
- Description: The objective of this study was to investigate the effect of species variations on chemical composition and in vitro ruminal degradability of Vachellia karroo, Grewia Occidentalis, Diospyros Lycioides and Ziziphus Mucronata fruits harvested from communally grazed lands in Alice, Eastern Cape Province, South Africa. The browse fruits were collected between February and May and analysed for crude protein (CP), dry matter (DM), ash, neutral detergent fibre (NDF), acid detergent fibre (ADF), organic matter (OM) and acid detergent lignin (ADL), condensed tannins (CT), macro minerals (Calcium (Ca), Magnesium (Mg), Potassium (K), Sodium (Na) and Phosphorus(P)) and micro minerals (Ion (Fe), Zinc (Zn), Manganese (Mn) and Copper (Cu)). There was significant variation (P<0.05) in chemical composition between browse fruits. The CP content differed significantly amongst the browse fruits, but all contained enough to meet the maintenance requirements of ruminants. Fruits from V. Karroo had higher (P<0.05) CP (182.26 g/kg DM), DM (896.50 g/kg DM) and ash (55.60 g/kg DM) contents compared to other browse species, while D. Lycioides fruits had higher (P<0.05) OM (951.60 g/kg DM) content than other browse fruits. Fruits harvested from G. Occidentalis had higher (P<0.05) ADF (513.27 g/kg DM), NDF (577.22 g/kg DM) and ADL (223.20 g/kg DM) content compared to other browse fruits. Fruits from V. Karroo had higher (P<0.05) CT (269.33 g/kg DM) content followed by Z. Mucronata (187.46 g/kg DM), while D. Lycioide (54.22 g/kg DM) and G. Occidentali (66.65 g/kg DM) had the same CT contents (P>0.05). There was a significant variation between browse species in macro and micro mineral contents. Fruits from G. Occindelis (43.93 g/kg DM) and V. Karroo (43.44 g/kg DM) had higher (P<0.05) Ca content compared to Z. Mucronata (24.06 g/kg DM) and D. Lycioides (20.06 g/kg DM). Ziziphus Muronata had higher (P<0.05) P (1.96 g/kg DM) content than other browse fruits. Fruits form V.karroo had higher Mg (4.75 g/kg DM), K (11.50 g/kg DM) and Na 3888 g/kg DM) content compared to other browse species. Fruits from V. Karroo showed significantly higher micro mineral content compared to other species. In terms of dry matter degradability (DMD), incubation time had an apparent effect on degradability of browse fruits except at 4 hours. The DM degradability increased with the increase of time and after 48 hours DMD was found to be satisfactory since it was above the prescribed 40 to 50 percent. However, the presence of condensed tannins had an effect on ruminal degradability of browse fruits. It was concluded that browse fruits have the potential to be used as protein supplements during the dry season since they contain moderate levels of crude protein. However, caution should be taken when feeding these browse fruits since they contain condensed tannins that affect rumen degradability. , Thesis (MSc) (Chemistry) -- University of Fort Hare, 2021
- Full Text:
- Date Issued: 2020-01
- Authors: Sondzaba, Bavuyise
- Date: 2020-01
- Subjects: Ruminants
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/20882 , vital:46695
- Description: The objective of this study was to investigate the effect of species variations on chemical composition and in vitro ruminal degradability of Vachellia karroo, Grewia Occidentalis, Diospyros Lycioides and Ziziphus Mucronata fruits harvested from communally grazed lands in Alice, Eastern Cape Province, South Africa. The browse fruits were collected between February and May and analysed for crude protein (CP), dry matter (DM), ash, neutral detergent fibre (NDF), acid detergent fibre (ADF), organic matter (OM) and acid detergent lignin (ADL), condensed tannins (CT), macro minerals (Calcium (Ca), Magnesium (Mg), Potassium (K), Sodium (Na) and Phosphorus(P)) and micro minerals (Ion (Fe), Zinc (Zn), Manganese (Mn) and Copper (Cu)). There was significant variation (P<0.05) in chemical composition between browse fruits. The CP content differed significantly amongst the browse fruits, but all contained enough to meet the maintenance requirements of ruminants. Fruits from V. Karroo had higher (P<0.05) CP (182.26 g/kg DM), DM (896.50 g/kg DM) and ash (55.60 g/kg DM) contents compared to other browse species, while D. Lycioides fruits had higher (P<0.05) OM (951.60 g/kg DM) content than other browse fruits. Fruits harvested from G. Occidentalis had higher (P<0.05) ADF (513.27 g/kg DM), NDF (577.22 g/kg DM) and ADL (223.20 g/kg DM) content compared to other browse fruits. Fruits from V. Karroo had higher (P<0.05) CT (269.33 g/kg DM) content followed by Z. Mucronata (187.46 g/kg DM), while D. Lycioide (54.22 g/kg DM) and G. Occidentali (66.65 g/kg DM) had the same CT contents (P>0.05). There was a significant variation between browse species in macro and micro mineral contents. Fruits from G. Occindelis (43.93 g/kg DM) and V. Karroo (43.44 g/kg DM) had higher (P<0.05) Ca content compared to Z. Mucronata (24.06 g/kg DM) and D. Lycioides (20.06 g/kg DM). Ziziphus Muronata had higher (P<0.05) P (1.96 g/kg DM) content than other browse fruits. Fruits form V.karroo had higher Mg (4.75 g/kg DM), K (11.50 g/kg DM) and Na 3888 g/kg DM) content compared to other browse species. Fruits from V. Karroo showed significantly higher micro mineral content compared to other species. In terms of dry matter degradability (DMD), incubation time had an apparent effect on degradability of browse fruits except at 4 hours. The DM degradability increased with the increase of time and after 48 hours DMD was found to be satisfactory since it was above the prescribed 40 to 50 percent. However, the presence of condensed tannins had an effect on ruminal degradability of browse fruits. It was concluded that browse fruits have the potential to be used as protein supplements during the dry season since they contain moderate levels of crude protein. However, caution should be taken when feeding these browse fruits since they contain condensed tannins that affect rumen degradability. , Thesis (MSc) (Chemistry) -- University of Fort Hare, 2021
- Full Text:
- Date Issued: 2020-01
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