https://vital.seals.ac.za/vital/access/manager/Index en-us 5 https://vital.seals.ac.za/vital/access/manager/Repository/vital:4330 Wed 12 May 2021 23:40:38 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:5864 Wed 12 May 2021 23:36:15 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:5267 Wed 12 May 2021 23:08:08 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:4958 Wed 12 May 2021 21:01:24 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:5180 0.05). There is no need to implement a seasonal dietary regime. Cultured H. midae were fed artificial diets with different protein sources, including only soya, only fishmeal, a combination of soya and fishmeal, and these were compared to kelp-fed abalone. Kelp-fed abalone grew slower than those fed artificial feeds (p>0.05). Gonad growth was the greatest when soya meal was included in the diet (average GBI: 74.91 ± 23.31), while the average gonad size of abalone fed the fishmealbased diet had gonads which were 38% smaller, and kelp-fed abalone had gonads which were 75% smaller than those of the abalone fed on diets containing soya meal. The increased gonad mass in abalone fed on diets including soya meal could be attributed to phytoestrogenic activity, as a result of the presence of isoflavones found in the soya plant; this remains to be tested. The use of soya in brood stock diet development is advised. The influence of dietary protein to energy ratio (1.41 – 2.46 g MJ⁻¹) on growth and gonad size was tested. Protein and energy levels within the ranges tested (22 and 33% protein; 13.5 and 15.6 MJ kg⁻¹) did not interact to influence growth rates of cultured H. midae. GBI increased from 50.67 ± 4.16 to 83.93 ± 9.35 units as a function of dietary protein to energy ratio (y = 42.02 x⁰·⁸¹; r² = 0.19; regression analysis: F₁¸₃₈ = 8.9; p = 0.005). In addition, protein level influenced gonad size, with gonad growth being greater in abalone fed the high protein diet (factorial ANOVA: F₁¸₃₂ = 7.1, p = 0.012). Canning yields were reduced by 7% when the protein content was increased, while increasing the quantity of dietary energy improved canning yields by ~ 6% (one-way ANOVA: F₁¸₂₈ = 14.4, p= 0.001). The present study provided evidence that although growth rates are varying seasonally, reproductive investment is not hindering weight gain. Gonad growth can be influenced if desired by farms, depending on the level of soya inclusion, as well as the protein to energy ratio in the diet. Monthly variation in growth and gonad size, as well as the influence of diet on gonad growth were highlighted, and the implications for farm application and further research were discussed.]]> Wed 12 May 2021 19:35:49 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:4236 Wed 12 May 2021 17:53:34 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3846 Thu 13 May 2021 05:15:29 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:5247 Thu 13 May 2021 05:14:49 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:5124 0.05) differences for muscle activity between conditions, except for the semitendinosus muscle, which was significantly (p< 0.05) higher during the control condition while running at high speeds. Players‘ heart rates, core temperatures and perceptual responses were significantly (p< 0.05) higher during the experimental condition, compared to the control condition. Performance responses were significantly (p< 0.05) lower during the experimental condition. Conclusion: The main driver of physiological and perceptual responses was the exercise itself. However, the additional clothing and protective gear exacerbated the responses, particularly towards the end stages of the protocol. This negatively impacted players‘ performance. Muscle activity appeared to be unaffected by increased body temperatures. However, core temperatures never reached critically high levels during either condition.]]> Thu 13 May 2021 04:19:45 SAST ]]>