The Indo-Pacific bottlenose dolphin (Tursiops aduncus) is a common top predator along the KwaZulu-Natal coast. There have been several dietary studies done on this species, most of which have classed this predator as an opportunistic feeder preying on the most abundant prey species in that area. In KwaZulu-Natal (KZN) a dietary study was carried out in 1990, but there have been no followup studies to examine potential changes in diet. A number of bottlenose dolphins get entangled in the shark-nets set off the KZN coast each year. These dolphins provide a valuable source of information about different aspects of the ecology of this population. The aim of this study was to examine the diet of bottlenose dolphins off the KwaZulu-Natal coast with particular emphasis on temporal change in diet composition. The contents of 102 stomachs of bottlenose dolphins (58 females, 44 males) accidentally caught in the shark nets between 1985 and 2010 were analysed, and compared to historical data from dolphins caught between 1975 and 1986. A total of 94 different prey species from 37 families (32 fish families, five cephalopod families) were identified in the stomach contents. Teleosts made up the most important prey group in numbers and weight constituting 84 percent and 67 percent, respectively, while cephalopods made up 15 percent of the number and 30 percent of the weight of the prey items. Multi Dimensional Scaling (MDS) indicated that there is no resource partitioning between males and females, but significant partitioning between juveniles and adults. Six prey species contributed more than 60 percent of the weight of all prey species in the diet. These species are the most important according to their calculated index of relative importance score and are, in order of importance: Sepia sp. (cuttlefish)., Pomadasys olivaceus (piggy), Trachurus delagoa (maasbanker), Scomber japonicus (mackeral), Loligo sp. (squid). and Pagellus bellottii natalensis (pandora or red tjor-tjor). When compared to historic data, no changes in the main prey species has occurred, but the piggy has decreased in importance (1976-1986 percent IRI=45; 2000-2010 percent IRI=22), while the maasbanker has increased (1975-1986, percent RI=4; 2000-2010 percent RI=20). Stable carbon and nitrogen isotope analysis performed on tissue from the teeth of T. aduncus caught in the shark nets between 1970 and 2010 showed that there has been no significant shift in trophic level (δ15N) or in primary prey source (δ13C) over this time. The isotopic signatures of different tissues from an individual were used to create a base line and describe the differences in tissue signatures. Blubber was found to be significantly different from skin and muscle, which were found to be isotopically similar. Skin from remote biopsies can therefore probably be used in place of muscle for isotopic studies of bottlenose dolphins, while caution should be taken when using blubber. Given that T. aduncus is still listed as “data deficient” by the International Union for the Conservation of Nature (IUCN), and the potential for climate change and expanding fisheries to alter the distribution and abundance of their prey species, long term dietary studies such as this are important in order for their effective conservation and management.

Thesis (Msc Food Sc (Food Science))--University of Stellenbosch, 2009. / An 84-day study was conducted to find a suitable diet and feeding level for the culture of South African abalone (Haliotis midae) in Namibia. Two experimental diets, namely, a seaweed diet (SWD) Laminaria pallida (macrophytic algae) and a formulated diet (FD) (macro-algae), for use in abalone (Haliotis midae) feed development, were evaluated. The animals used in this study were juveniles (24.33 ± 3.14 mm shell length; 2.72 ± 0.83 g live weight, mean ± SE) and sub-adults (58.07 ± 10.33 mm shell length and 41.96 ± 20.61 g live weight, mean ± SE). The nutrient profile of the SWD and FD displayed no differences in the protein and carbohydrate levels. Crude protein levels ranged from 4.91 to 17.68% (dry matter (DM) basis). The lipid levels in the FD (0.25%) were almost 0.56% lower than that in the SWD (0.76%). The feed conversion ratio (FCR) and protein efficiency ratio (PER) for the sub-adult abalone ranged from 2.80 to 10.90 and 0.10 to 0.40, respectively. The juvenile abalone fed on the FD yielded significantly lower (P < 0.05) FCRs (0.8) and higher PERs (1.20) than their counterparts fed on the SWD. A similar trend was observed for the sub-adult abalone although the differences were not significant (P > 0.05). The relative growth rate (RGR) of juvenile fed on the FD was 25% lower compared to those fed on the SWD, while that of the sub-adult abalone fed on the FD was 29% lower compared to the abalone fed on the SWD. From the daily growth rate (DGR) in terms of daily body weight (DGRBW) calculated after the 84-day period, repeated-measures ANOVA (RANOVA) indicated no interaction between time period and diet. Although slightly lower, the DGRBW for the juvenile abalone fed on the SWD diet (0.033 g/day) did not differ significantly from the DGRBW of abalone fed on the FD (0.079 g/day). In contrast, sub-adult abalone fed on the SWD exhibited significantly higher DGRBW compared to those fed on the FD. Although the abalone fed on the FD was slightly higher in nutritional content, there was no significantly difference (P > 0.05) in the nutritional profile of the abalone soft body tissue fed on either the SWD or FD. There was no significant (P > 0.05) difference in preference when comparing the aroma of the abalone meat samples fed on either the SWD or FD. However, there was a significant difference (P < 0.05) in the consumers’ preference in terms of flavour for the abalone sample fed on the FD. The trained taste panel results indicated that there was no difference in the aroma and flavour of the abalone fed on the different diets (P > 0.05). This study showed that cultured juvenile H. midae, readily accepted a FD, producing high consumption and survival rates. The FD still warrants further refinement and testing for it to become a more effective mariculture feed with commercial potential.

Subtropical thicket supports a large variety of indigenous browsing herbivores, such as elephants, black rhino, kudu and bushbuck, but impala historically never occurred in the Eastern Cape. The aim of this study was to determine what impacts extralimital impala (Aepyceros melampus) have on subtropical thicket. The thicket of the Shamwari Game Reserve, Eastern Cape, was used for the study. To quantify the effects of impala, feeding behaviour and diet was investigated during summer and winter. Sixteen impala were also enclosed in a camp of subtropical thicket where they would be limited to feedings on thicket. Vegetation composition and structure were monitored for a period of 12 months in the enclosure. Impala followed the expected high percentage graze and a low percentage browse in thicket in summer. However, the expected was not observed during winter: at this time grazing and browsing were equally important. Field collection of feeding behaviour data showed that impala are attracted to fringes of intact bush clumps or degraded thicket. Analysis of the impala diet confirmed this, with a significantly higher percentage graze (48 percent) than browse (22 percent) during summer. However, during winter, diet analysis indicated grazing to be much higher (36 percent) than browsing (6 percent) with the impala temporarily taking advantage of nutritious grasses still present. The enclosed portion of thicket was originally at 80 percent ecological status but it showed significant changes after addition of 16 impala. Animal trails increased in number and in width, resulting in a trampling effect. Grass cover was significantly different inside the enclosure after 12 months compared to outside. The amount of available browse of the enclosed thicket was also significantly different after addition of the impala. It is concluded that impala have a negative effect on thicket, with trampling the most significant effect. Long term monitoring of the effects of extralimital impala in different types of thicket will be required to accurately quantify their direct effects on subtropical thicket in the Eastern Cape. The main aim of this study was to determine the impacts of impala on Thicket. The study showed significant impacts on Thicket as found in Shamwari, and therefore the aim of the study was achieved.

Thesis (M. Sc. (Aquaculture)) -- University of Limpopo, 2021 / Tilapia production in South Africa is failing to reach sustainable commercial levels of development, despite the efforts by the government to improve aquaculture production. Limpopo Province has been practicing fish farming since the 1980s, with tilapia being the most widely farmed fish. Currently, tilapia production in Capricorn and Vhembe districts in Limpopo Province remains low. In this study, factors affecting tilapia production in aqua dams, earthen ponds, concrete ponds, and RAS systems in Capricorn and Vhembe districts were explored. Eight different production systems were used to collect field data, four in each district. Water quality parameters in aqua dams, earthen ponds, concrete ponds, and RAS system were determined. The abundance of phytoplankton was determined in three different production systems. And lastly, a questionnaire was used to determine factors critical for successful tilapia production from the farmer’s perspective in Capricorn and Vhembe districts. The levels of ammonium and ammonia were below detection limits in all the production systems in Capricorn and Vhembe districts. The results showed that water temperature, alkalinity (as bicarbonate and carbonate), potassium, total phosphate frequently did not meet the requirement for the culture of tilapia in all the production systems in Capricorn and Vhembe district throughout the study. The concrete ponds, aqua dams, and RAS systems in both districts were mostly affected by these parameters. The phytoplankton abundance varied according to the type of production system and water quality parameters of the production systems. The concrete pond in Olifanshoek, Vhembe district had the highest total phytoplankton composition. An aqua dam in Bungeni had the highest total phytoplankton composition compared to other aqua dams in Capricorn district. The earthen ponds in Vondo in Vhembe district had the lowest tilapia yield and total phytoplankton composition compared to all the production systems in Capricorn and Vhembe districts. Phytoplankton species abundance was not correlated to primary production and tilapia yield, and there was no correlation between primary production and tilapia yield. Tilapia farmers in Capricorn and Vhembe district both ranked “value chain accessibility”, “appropriate technology approach”, “market factors”, “level of operational integration”, and “access to multiple market destination” as the most important socio-economic factors affecting tilapia production in both districts. Tilapia vii production in Capricorn and Vhembe districts is not profitable because of low tilapia yields due to low stocking densities and because of low-priced imported tilapia from China and low-priced wild-caught tilapia sold by local fishermen in villages. The study concluded that tilapia production in Capricorn and Vhembe districts is not successful because farmers struggle to maintain optimum water quality and the water temperature was suitable for tilapia farming only for a short period of time. And lastly, tilapia production is failing to succeed in Capricorn and Vhembe district because it is not profitable. / Department of Agriculture, Land Reform and Rural Development and the Aquaculture Research Unit

Thesis (MSc. (Animal Production)) -- University of Limpopo, 2018 / A study was done to determine the effect of Acacia (A.) karroo, A. tortilis or A. nilotica leaf meal inclusion in a diet on methane emission and productivity of yearling male Boer goats fed a basal diet of Avena sativa hay. The first part of the study was conducted to determine and compare nutrient contents and tannin levels of A. karroo, A. tortilis and A. nilotica leaf meals and Avena sativa hay in a completely randomised design. The diets means were compared using Fisher’s least significant difference at the 5 % level of probability. The three Acacia species had higher (P<0.05) crude protein contents compared to Avena sativa hay, ranging from 12.42 to 14.49 %. No tannins were detected in Avena sativa hay. Among Acacia species, A. nilotica leaves had higher (P<0.05) total phenolic and total tannin contents than A. karroo and A. tortilis leaves, the latter being similar (P>0.05). All three Acacia species had similar (P>0.05) contents of condensed tannins, ranging from 1.49 to 1.76 %. However, only A. nilotica leaves had hydrolysable tannins of 128 mg/g. The second part of the study was conducted to determine the effect of A. karroo, A. tortilis or A. nilotica leaf meal inclusion level on diet intake and digestibility, methane emission, productivity and blood profiles of yearling male Boer goats. A total of three experiments were conducted and different goats were used in each experiment. A grand total of thirty six (twelve per experiment) yearling male Boer goats with initial mean live weights of 23 ± 2 kg (experiment 1), 23 ± 2 kg (experiment 2) and 23 ± 2 kg (experiment 3) were used in 21-day experiments. The goats were randomly assigned to four dietary treatments, each containing A. karroo, A. tortilis or A. nilotica leaf meal inclusion levels at 10, 15, 20 and 30 % with Avena sativa hay as a basal diet. Each goat was housed in well-ventilated individual metabolic pen. The diets were replicated three times. The data collected were subjected to analysis of covariance and analysis of variance in a completely randomized design using SAS. Differences were separated at 5 % level of probability. Additionally, regression equations were used to determine the relationships and responses in optimal diet intake and digestibility, methane emission, productivity and blood profiles of yearling male Boer goats to differing inclusion levels of A. karroo, A. tortilis and A. nilotica leaf meal. v Experiment 1 involved feeding different levels of A. karroo leaf meal inclusion to yearling male Boer goats fed Avena sativa hay as a basal diet. Results of methane emission before and during the experiment indicated that inclusion of A. karroo leaf meal in the diets of goats reduced (P<0.05) methane emission. Similarly, some of the blood parameters before and after experiment were affected (P<0.05) by inclusion of A. karroo leaf meal. However, A. karroo leaf meal inclusion level had no effect (P>0.05) on diet intake, methane emission, live weight changes and digestibility, except (P<0.05) for digestibility of crude fibre. Feed conversion ratio improved linearly with increased A. karroo leaf meal inclusion level. In the case of experiment 2, results of methane emission before and during the experiment indicated that inclusion of A. tortilis leaf meal in the diets of goats reduced (P<0.05) methane emission. Similarly, some of the blood parameters before and after the experiment were affected (P<0.05) by inclusion of A. tortilis leaf meal. However, variation in A. tortilis leaf meal inclusion level had comparable effect (P>0.05) on methane emission, live weight changes and digestibility, except (P<0.05) for digestibility of crude protein and acid detergent fibre. Diet intake and feed conversion ratio were affected (P<0.05) by A. tortilis leaf meal inclusion level. A positive relationship was observed between A. tortilis leaf meal inclusion level and diet intake. In experiment 3, results of methane emission before and during the experiment indicated that inclusion of A. nilotica leaf meal in the diets of goats reduced (P<0.05) methane emission. Similarly, some of the blood parameters before and the after experiment were affected (P<0.05) by inclusion of A. nilotica leaf meal. Apart from diet fat digestibility and feed conversion ratio, no statistical differences (P>0.05) were observed on diet intake, digestibility and live weight changes of goats fed A. nilotica leaf meal inclusion level. Positive relationships were observed between A. nilotica leaf meal inclusion level, diet fat digestibility and feed conversion ratio in male Boer goats. The high crude protein and low tannin contents in A. karroo, A. tortilis and A. nilotica leaves indicate that these Acacia species can be safe to use as a source of protein in animal nutrition if used sparingly. It was noted that nutrient intake, digestibility, vi feed conversion ratio and blood profiles of Boer goats in the present study were optimised at different inclusion levels for all the three Acacia species. This may imply that inclusion levels of A. karroo, A. tortilis and A. nilotica leaf meals for optimal productivity will depend on the Acacia species used and, also, on particular productivity parameters in question. Although, A. karroo, A. tortilis and A. nilotica leaf meal reduced methane emission, optimal reduction in methane emission was not determined. Further validation is required to determine Acacia inclusion levels for optimal methane production and emission by goats. / NRF (National Research Foundation), AGRISETA (Agricultural Sector and Education Training Authority) and NSFAS (National Students Financial Aid Scheme)

Protein has been identified as a major reason that people purchase a horse feed, with anecdotal explanations offered for the poor prediction of response of horses to their rations, particularly in the sport horse market. The current research identifies through hierarchical cluster analysis that the myriad of riding feeds offered on the South African market fall into only four simple categories on the basis of wet chemistry. Feeds were subjected to the in vitro gas production technique (IVGPT) described by Pell and Schofield (1993), using equine faecal inoculum. Gas profiles, corrected for control fermentation profiles in the absence of substrate, were fitted to the model described by Campos et al. (2004) to derive GP kinetics. Gas production kinetics, and information in respect of pH, degradation efficiency, lag time and apparent and true digestibilities were obtained. The feeds were tested for glycaemic response in miniature horses using the hexokinase method with deproteinization using an auto analyser (Roche Diagnostics). Blood glucose parameters of feeds (mean, peak, slope and time to peak and area under the curve) in each group were compared by analysis of variance and regression with covariates. In vivo analysis of rates of passage and digestibility using using post-prandial percentages of acid insoluble marker collection was used to study the gastrointestinal process, to indicate foregut and hindgut compartmental flow. The need to balance nitrogen levels with a proportional supply of fermentable carbohydrate contradicts widely used protein intakes in the horse. In vitro fermentation was used in an analysis of nutrient synchrony, to identify optimal fermentative capacity for utilization of horse feeds. The characteristics of horse feeds were related to requirement and were composited in an analysis of the representation of horse feeds that would best reflect optimal utilization in the horse, to produce a method of feed characterisation that would lead to the optimal prediction of response of horses to feeds offered to South African horses. / Thesis (Ph.D.Agric.)-University of KwaZulu-Natal, Pietermaritzburg, 2011.

Goats are found in almost every country and are an important source of protein and produce lactose-free milk. In South Africa, survival rates of goat kids are low, mainly due to malnutrition. Intensive goat production systems based on cultivated pastures were evaluated, at various stocking rates to evaluate the effects of improved nutrition on goat production. The pastures chosen to be evaluated for goat production were Pennisetum clandestinum (Kikuyu) and Secale cereale (Stooling rye). Kikuyu is one of the more important dryland summer pasture species in KwaZulu-Natal. Three stocking rates of goats on kikuyu were evaluated using ewes with kids. When analysing the period to weaning, the ewes lost weight in all stocking rate treatments and for both years. The years had a significant effect on weight loss (P<0.001; R²=95.7%) with a mean ADG of -0.0267 kg.animalˉ¹.dayˉ¹. There was a significant difference between ADGs between stocking rates, with ADGs of -0.0157, -0.026 and -0.0384 kg.animalˉ¹.dayˉ¹ at stocking rates of 30, 45 and 60 goats.haˉ¹ respectively (P<0.001; R²=95.7%). The analyses of the entire grazing period showed no significant difference in ewe ADGs between treatments, but a significant difference between the two years (P=0.03), with a mean ADG of -0.0205 kg.animalֿ¹.dayֿ¹. There was no significant difference between kid masses between treatments. There was a significant difference between kid performance between years (P<0.001; R²=21.8%). However, factors such as ewe start mass (P<0.001) and whether the kid was a singleton or a multiple (P=0.015) had an influence on kid ADG, while gender had no significant effect (P=0.446). Interpretation of the combined ewe plus kid weight revealed that the high stocking rate produced the highest total mass per hectare (P<0.001) with an overall mean of 2377 kg.haˉ¹. Kid ADG was positively correlated to ewe ADG (P=0.013; R²=5.8%) although this was not a strong relationship. Protein was negatively correlated to pasture height (P=0.036; R²=30.8%) and had a quadratic relationship with ADG (P<0.001; R²=48.4%) with maximum ADG occurring at protein levels of 26.17%. Rainfall was different between the two seasons, which affected pasture growth, with the stocking rates in the second year being too low, so the maximum stocking rate per hectare was not reached. Stooling rye is a pasture used predominantly in South Africa and is a good source of high quality winter feed. Four stocking rates were evaluated over winter, using pregnant ewes. Rainfall was not an important variable since supplementary irrigation was given and the difference in temperatures between the years was negligible. The rate of weight gain showed a similar response for both years with the level of weight gain varying significantly between years (P=0.001; R²=90.2%). The regressions for ADG on stocking rate were determined and were y=0.2340-0.00293x for 2001 (P=0.151; R²=58.0%) and y=0.1292-0.002198x for 2002 (P=0.137; R²=61.6%). Gain per hectare was determined, as were the stocking rates at which maximum gain per hectare were achieved and this was determined to be 40 goats.haֿ¹ during 2001 and 29 goats.haֿ¹ for 2002. The respective ADGs at these stocking rates were 0.1168 and 0.0633 kg.dayֿ¹ and daily gains.haֿ¹ were 4.672 and 1.898 kg.haֿ¹.dayֿ¹ respectively. Herbage analyses revealed that there were extremely high levels of protein in the pasture (33.87%) even though the pasture was not excessively fertilised. Average daily gain was negatively related to NDF levels (P=0.006; R²=38.4%). ADF levels (P<0.001; R²=48.4%) and NDF levels (P<0.001; R²=60.4%) showed a quadratic relationship with pasture age. Blood serum revealed that selenium levels in all treatments were lower than the normal range, while all other minerals were within the normal range. To maximise animal performance, the highest quality pasture should be offered to producing animals, namely growing animals. The seasonal variation between years has a large effect on the performance of goats on pastures. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2011.

According to farm records, cultured Haliotis midae (50-70 g.abalone⁻¹) were growing 10% slower in winter when compared to summer. This reduction in growth rate also coincided with enlarged gonads. Initial trials showed that there were differences in mean monthly growth rates ranging from 1.97 – 5.14 g abalone⁻¹ month⁻¹, and gonad bulk index (GBI) also varied between months (GBI range: 26.88 ± 12.87 to 51.03 ± 34.47). The investment of energy into gonad tissue growth did not compromise whole body growth as the abalone continued to gain weight throughout the reproductive periods, probably due to gonadal growth. Growth of this size class of abalone was not influenced by water temperature or day length, suggesting favourable on-farm culture conditions (regression analyses, p > 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.

Abalone, Haliotis midae, farmers in South Africa that feed formulated diets reported a periodic drop in abalone growth during periods of increased gonad development. A large drop in abalone biomass was noticed after presumed spawning events. This study was aimed to determine the effect of diet and sex-sorting on gonad development in abalone. Experiments were conducted on a commercial abalone farm from July 2012 to the end of June 2013. Isonitrogenous and isoenergetic diets were formulated with two protein sources. A fishmeal and soybean meal (S-diet) diet and a fishmeal only (F-diet) diet were fed to abalone (50 - 70 g abalone⁻¹) over 12 months. Weight and length gain, gonad bulk index (GBI), visceral index (%) and meat mass index (%) were determined monthly and seasonally. A histological study on the female gonads was conducted. This study also included an experiment to test the effect of sex-sorting (70 - 80 g abalone⁻¹) on growth and body composition with treatments including males (M), females (F) and equal numbers of males and females (MF). Weight gain and length gain were faster in S-diet-fed abalone (RM-ANOVA, F ₍₁, ₁₆₎ = 7.77, p = 0.01; F ₍₁, ₆₉₎ = 49.9, p < 0.001, respectively). Gonad development was significantly affected by the inclusion of soybean meal with S-diet-fed abalone showing higher GBI-values than F-diet-fed abalone (RM-ANOVA, F ₍₁, ₃₃)= 16.22, p = 0.0003). Male abalone had higher GBI-values than females (RM-ANOVA, F ₍₁, ₃₃₎ = 39.87, p < 0.0001). There was no significant difference in average feed conversion ratio (FCR) between diets over time (RM-ANOVA, F ₍₁, ₂₁₎ = 0.008, p = 0.97). However, average FCR-values were significantly highest between November 2012 and March 2013, the presumed spawning season. The visceral mass (gut and gonad) as a proportion of whole mass (visceral index, %) was significantly higher in abalone fed the S-diet (RM-ANOVA; F ₍₁, ₆₉₎ = 68.06, p < 0.0001). There was no difference in meat mass index (%) between diets for both male and female abalone (RM-ANOVA; F ₍₇, ₂₄₈₎ = 0.80, p = 0.60; F ₍₇, ₂₄₁₎ = 1.7, p = 0.11,respectively). Meat mass index significantly decreased from September 2012 to February 2013 coinciding with the period of high GBI-values. The distribution of oocyte maturity stages differed between diets. The majority of oocytes within S-diet-fed abalone were fully mature stage 8 oocytes compared to a majority of stage 7 oocytes in F-diet-fed abalone. Histology corroborated peaks in GBI-values for abalone fed both diets. There was no significant difference in growth, GBI, visceral index (%) and meat mass index (%) between abalone sorted into monosex and mixed-sex populations. Thus, the presence of the opposite sex did not have an effect on growth and gonad mass in H. midae. The phytoestrogens daidzin, glycitin, genistin, daidzein, glycitein and genistein were present in soybean meal and only traceable amounts were found in the F-diet. This study provided evidence that soybean meal present in formulated feed affected growth and gonad development in H.midae. The difference in the distribution of the maturity stages of oocytes was affected by diet. Sex-sorting abalone into monosex and mixed-sex populations had no influence on weight and length gain and gonad development.

Effects of Acacia karroo supplementation on meat quality of Xhosa Lop-Eared goats The objective of the study was to determine the effects of A. karroo supplementation on the quality of meat from Xhosa lop-eared goats. Eighteen castrated 4-month-old Xhosa lop-eared male kids were kept at the University of Fort Hare Farm until slaughter. At the beginning of the experiment the goats had a mean body weight of 13.5 ± 0.31 kg (mean ± S.E.) and a mean body condition score (BCS) of 3.3 ± 0.16 (mean ± S.E.). From birth until weaning the kids were kept on natural pastures with their mothers. After weaning the goats were housed in an open sided barn for a period of 60 days, and were fed 500 g/head/day of Medicago sativa hay covering their maintenance and growth needs. For the purpose of the experiment, the goats were randomly divided into two balanced treatment groups of nine goats each, supplemented group (AK) and non-supplemented group (NS). The supplemented group received an additional 200g per head per day of fresh A. karroo leaves collected each day for two months. Supplementary feed was given to the goats individually in feeding troughs. The kids were slaughtered at 60 days old and samples for meat quality assessment were taken from the Longistimus dorsi muscle. The effect of A. karroo supplementation on meat quality measurements such as ultimate pH, colour and cooking losses of meat from indigenous Xhosa lop-eared goats were determined. The effect of A. karroo supplementation on the consumer sensory characteristic scores of the meat from the indigenous Xhosa lop-eared breed was also determined. There was a significant effect of the A. karroo supplementation on the meat quality measurements except for L* and a* colour coordinates. Meat from the A. karroo supplemented goats had lower pH and cooking loss scores than that of the non-supplemented goats. Acacia karroo supplementation improves meat tenderness and juiciness. There were no significant effects of A. karroo supplementation on the flavour and off- iv flavours of the meat from the supplemented goats. However, thermal preparation and consumer background had a significant effect on the meat sensory characteristics. The cooked meat had significantly higher sensory scores than the roasted meat. Female consumers reported higher sensory scores than male consumers. Consumers of different tribes and ages also reported significantly different sensory scores of meat from indigenous Xhosa lop-eared goats. Therefore, this study indicated that A. karroo supplementation can be fed to the Xhosa lop-eared goats to improve their meat quality.