Thesis (M.Sc. (Animal Production)) --University of Limpopo, 2010 / A study was conducted to determine the effect of vitamin E supplementation to the diets of Venda hens on egg production, hatchability and chick productivity. The first part of the study determined the effect of vitamin E supplementation to the diets of Venda hens on feed intake, number of eggs, egg weight, egg content, egg hatchability and chick hatch-weight. Supplementation levels of 0, 200, 400, 800 and 1000 mg of vitamin E per kg DM feed were used in a completely randomized design having five replications with two birds per replicate. Vitamin E supplementation did not have any effect (P<0.05) on number of eggs and feed intake of Venda hens. However, egg weight, egg content, hatchability and chick hatch-weight of Venda chickens improved (P<0.05) with vitamin E supplementation. Dietary vitamin E supplementation values for optimal egg white weight, egg yolk nitrogen content, egg white nitrogen content, egg hatchability and number of eggs were 476 (r2 = 0.756), 750 (r2 = 0.170), 750 (r2 = 0.182), 445 (r2 = 0.670) and 113 (r2=0.966) mg of vitamin E per kg DM feed, respectively. The second part of the study determined the effect of vitamin E supplementation to the diets of Venda hens on performance of their progenies between one and seven weeks old. A completely randomized design was used. All the chickens were fed the same commercial grower diet. Dietary vitamin E supplementation to the diets of Venda hens had no effect (P<0.05) on growth rate and mortality of their progenies between one and seven weeks. Feed intake, feed conversion ratio and live weight of progenies improved (P<0.05) with supplementation of vitamin E to the diets of Venda hens. Dietary vitamin E supplementation to the diets of Venda hens did not have any effect (P<0.05) on dry matter intake, dry matter digestibility, nitrogen retention and metabolisable energy of their progenies at seven weeks old. vi The third part of the study determined the effect of vitamin E supplementation to the diets of Venda hens on performance of their male progenies aged between eight and 13 weeks. A completely randomized design was used. All the chickens were fed the same commercial grower diet. Vitamin E supplementation to the diets of Venda hens did not improve (P<0.05) feed intake, growth rate, feed conversion ratio, live weight and mortality of their male progenies between eight and 13 weeks old. However, Venda hens supplemented with vitamin E produced male progenies with improved (P<0.05) dry matter intake, digestibility, nitrogen retention metabolisable energy, breast meat nitrogen content, gizzard weight, liver weight and heart weight at 13 weeks old. Carcass weight, breast meat yield, drum stick, thigh and wing weight of chickens at 13 weeks old were not affected (P>0.05) by vitamin E supplementation to the diets of the hens It is concluded that supplementation of vitamin E to the diets of indigenous Venda hens improved (P<0.05) egg weight, egg content and chick hatch-weight during the laying period. Vitamin E supplementation to the diets of Venda hens improved (P<0.05) feed intake, live weight, feed conversion ratio, gizzard and liver weight of their progenies. Production variables were optimized at different levels of vitamin E supplementation. Thus, this study provided new information on the effect of vitamin E supplementation to the diets of indigenous Venda hens on chick productivity and carcass characteristics of their progenies.

Thesis (Ph. D. (Animal Production )) -- University of Limpopo, 2013 / Eight experiments were conducted to determine the effect of dietary lysine to energy ratio on the productivity and carcass characteristics of indigenous Venda chickens aged one to thirteen weeks and raised in closed confinement. The eight experiments were based on four different energy levels of 11, 12, 13 and 14 MJ of ME/kg DM. Each dietary energy level had four different levels of dietary lysine (8, 9, 11 and 14 g lysine/kg DM). Thus, different dietary lysine to energy ratios were calculated. Experiments 1 to 4 determined the effect of dietary lysine to energy ratio on productivity of unsexed Venda chickens aged one to seven weeks. Each experiment commenced with 160 unsexed day-old indigenous Venda chicks with an initial live weight of 30 ± 3 g per bird and was carried out for seven weeks. In each experiment, the chicks were randomly assigned to four treatments with four replications, each having 10 chicks. A complete randomized design was used for each experiment. All data were analysed by one-way analysis of variance. Where there were significant differences, the Duncan test for multiple comparisons was used to test the significance of differences between treatment means. A quadratic regression model was used to determine the ratios for optimum productivity in each experiment while a linear model was used to determine the relationships between dietary lysine to energy ratio and optimal responses in the variables measured. Results indicated that dietary lysine to energy ratio for optimal responses depended on the variable of interest. In Experiment 1, feed intake, growth rate, live weight, ME intake and nitrogen retention were optimized at different dietary lysine to energy ratios of 0.722, 0.719, 0.719, 0.670 and 0.712, respectively. There was a positive and strong relationship (r2 = 0.950) between dietary lysine to energy ratio and feed conversion ratio (FCR). Results from Experiment 2 indicated that feed intake, growth rate, FCR, live weight, ME intake and nitrogen retention were optimized at dietary lysine to energy ratios of 0.719, 0.742, 0.788, 0.742, 0.734 and 0.789, respectively. In Experiment 3, dietary lysine to energy ratio did not have any effect (P>0.05) on all the parameters measured. However, quadratic analysis indicated that dietary lysine to energy ratios of 0.817, 0.883, 0.920, 0.898, 0.895 and 0.955 optimized feed intake, growth rate, FCR, live weight, ME intake and nitrogen retention of the chickens, respectively. Experiment 4 results showed that feed intake, growth rate, FCR, live weight ME intake and nitrogen retention were v optimized at different dietary lysine to energy ratios of 0.906, 0.964, 1.023, 0.966, 0.963 and 0.951, respectively. Experiments 5 to 8 determined the effect of dietary lysine to energy ratio on productivity, carcass characteristics, sensory attributes and haematological values of female indigenous Venda chickens aged eight to thirteen weeks. The layouts, treatments, design and execution were similar to those described for Experiments 1, 2, 3 and 4, respectively, except that Experiments 5 to 8 were for female indigenous Venda chickens aged eight to 13 weeks. These chickens were different from those used in Experiments 1 to 4. They were raised on a grower mash (16 % crude protein, 11 MJ of ME/kg DM and 180 g of lysine) prior to commencement of the study. Each experiment commenced with 120 eight weeks old female Venda chickens with an initial live weight of 412 ± 3 g per chicken. In each experiment, the chickens were randomly assigned to four treatments with five replicates, each having six chickens. Results obtained from Experiment 5 showed that feed intake, growth rate, FCR, live weight, ME intake, carcass weight, dressing percentage, breast meat, drumstick, wing weight, breast meat drip loss, juiciness, flavour, haemoglobin and pack cell volume were optimized at different dietary lysine to energy ratios of 0.672, 0.646, 0639, 0.649, 0.655, 0.656, 0.664, 0.669, 0.665, 0.663, 0.631, 0.708, 0.623, 0.556 and 0.609, respectively. In Experiment 6, the diets were formulated to have higher lysine to energy ratios than those in Experiment 5 by using a dietary lysine level of 9 g lysine/kg DM. Results from this experiment showed that feed intake, FCR, nitrogen retention, carcass weight, dressing percentage, breast meat, gizzard weights and breast meat pH at 2, 12 and 24 hours after slaughter were optimized at dietary lysine to energy ratios of 0.798, 0.613, 0.777, 0.742, 0.753, 0.729, 0.758, 0.752, 0.802 and 0.797, respectively. Red blood cell and haemoglobin values in this experiment were optimized at dietary lysine to energy ratios of 0.480 and 0.624, respectively. In Experiment 7, dietary lysine to energy ratios of 0.79, 0.85, 0.92 and 1.00 g lysine/ MJ of ME were used. Dietary treatments in this experiment had no effect (P>0.05) on all the production parameters measured except feed and apparent metabolisable energy intakes. Quadratic analysis of the results indicated that dietary lysine to energy ratios of 0.964, 0.912, 0.900, 0.890, 0.910, 1.090, 0.934 and 0.895 optimized feed intake, apparent metabolisable energy, carcass, breast meat, drumstick weights and vi breast meat drip loss, juiciness and flavour, respectively. A positive and very strong relationship (r2 =0.998) was observed between dietary lysine to energy ratio and pack cell volume. Experiment 8 diets were formulated to have higher dietary lysine to energy ratios than the other experiments. Results of this experiment indicated that all the production parameters were influenced (P<0.05) by dietary lysine to energy ratio except mortality. Feed intake, growth rate, feed conversion ratio, live weight, apparent metabolisable energy and nitrogen retention were optimized at dietary lysine to energy ratios of 0.996, 0.980, 0.991, 1.010, 0.957 and 0.993, respectively. Dietary lysine to energy ratios of 0.992, 0.974, 0.991, 0.992, 1.023, 0.981, 0.979 and 0.815 optimized carcass weight, dressing percentage, breast meat, drumstick, liver weights and breast meat tenderness, juiciness and flavour, respectively. There were variations in the optimal lysine to energy ratios for different parameters investigated. In a diet containing 8 g of lysine per kg DM, 11.13 MJ of ME/kg DM and 150 g of CP/kg DM, dietary lysine to energy ratios of 0.719 and 0.649 are recommended for optimal live weight of Venda chickens aged one to seven and eight to 13 weeks, respectively. In a diet containing 9 g of lysine per kg DM, 12.13 MJ of ME/kg DM and 180 g of CP/kg DM, dietary lysine to energy ratios of 0.742 and 0.712 are recommended for optimal live weight of Venda chickens aged one to seven and eight to 13 weeks, respectively. In a diet containing 11 g of lysine per kg DM, 12.51 MJ of ME/kg DM and 220 g of CP/kg DM, dietary lysine to energy ratios of 0.878 and 0.894 are recommended for optimal live weight of Venda chickens aged one to seven and eight to 13 weeks respectively. In a diet containing 12 g of lysine per kg DM, 12.05 MJ of ME/kg DM and 240 g of CP/kg DM, dietary lysine to energy ratios of 0.996 and 1.010 are recommended for optimal live weight of Venda chickens aged one to seven and eight to 13 weeks, respectively. The results obtained in this study showed that different production parameters of Venda chickens were optimized at different lysine to energy ratios. This implies that the nutritional requirements of these chickens are dynamic and thus, dietary lysine to energy for optimal production depends on the production parameter of interest. This has implications on ration formulation for indigenous chickens.

Thesis (M.Sc. Agric.(Animal Science)) --University of Limpopo, 2011 / An experiment was conducted to determine the effect of egg weight on hatchability, hatch-weight and subsequent productivity of Venda chickens. A total of 360 Venda chicken eggs based on their weights were collected within one week and assigned to four treatments with five replicates of 18 eggs per replicate. A randomized design was used. The four treatment weights were below 49 g, between 50 and 59 g, between 60 and 69 g and above 70 g. the eggs were incubated for 21 days. The chicks were raised up to 13 weeks based on their treatments but fed a similar diet. Egg weight was positively and strongly correlated (r2 = 0.727) with hatchability. Similarly, egg weight was positively and strongly correlated (r2 = 0.0.953) with chick hatch-weight. Between one and seven weeks old, Venda chicks hatched from heavier eggs ate less (P< 0.05) than those hatched from lighter eggs. Heavier eggs hatched chicks with better (P< 0.05) feed conversion ratio. However, chicks hatched from heavier eggs tended to have higher (P< 0.05) live weight at seven weeks old than those hatched from lighter eggs. Heavier eggs tended to hatch chicks that had higher (P< 0.05) mortality rates. However, metabolisable energy and nitrogen retention of the chicks aged seven weeks was not (P> 0.05) affected by egg weight. Growth rate and live weight of the chicks aged between one and seven weeks were optimized at different Venda chicken egg weights of 56 (r2 = 0.514) and 60 (r2 = 0.870) g, respectively. Egg weight had no (P> 0.05) effect on metabolisable energy, feed conversion ratio, growth rate, live weight, carcass weight and carcass parts of Venda chickens aged between eight and 13 weeks except fat pad weight. Venda chickens hatched from lighter eggs had lower (P< 0.05) fat pad weights than those hatched from heavier eggs. Meat samples of chickens hatched from lighter eggs had higher (P< 0.05) nitrogen contents. It is concluded that Venda chicken egg weight affects (P< 0.05) egg hatchability, chick hatch-weight, growth rate, live weight and carcass characteristics of the chicken. However, these variables are optimized at different egg weights. This has implications on selecting eggs for incubation.

Thesis (MSc. Agriculture (Animal Production)) -- University of Limpopo, 2014 / Two experiments were conducted to determine the effect of moringa seed meal supplementation on productivity and carcass characteristics of Ross 308 broiler chickens. The first experiment determined the effect of moringa seed meal supplementation on productivity of Ross 308 broiler chickens aged one to 21 days. Two hundred and fifty unsexed day-old Ross 308 broiler chicks were randomly allocated to five dietary treatments, replicated five times, and each replication having 10 chickens. A completely randomized design was used. The chickens were fed on a grower diet supplemented with 0 (M0), 5 (M5), 10 (M10), 15 (M15) and 20 (M20) g of moringa seed meal/bird/day. Moringa seed meal supplementation had no effect (P>0.05) on feed intake, metabolisable energy intake, nitrogen retention, feed conversion ratio and live weight of unsexed Ross 308 broiler chickens. Moringa seed meal supplementation improved (P<0.05) growth rates of unsexed Ross 308 broiler chickens aged one to 21 days. A moringa seed meal supplementation level of 13.3 g/kg DM feed optimized growth rate of Ross 308 broiler chickens aged one to 21 days. The second experiment determined the effect of moringa seed meal supplementation on productivity and carcass characteristics of female Ross 308 broiler chickens aged 22 to 42 days. The chickens weighing 558 ± 10 g/bird were randomly allocated to five treatments with five replications having 10 birds. The chickens, aged 21 days, were allocated to the treatments in a completely randomized design. The chickens were fed on a grower diet supplemented with 0 (FM0), 5 (FM5), 10 (FM10), 15 (FM15) and 20 (FM20) g of moringa seed meal per kg DM. Moringa seed meal supplementation had no effect (P>0.05) on feed intake, growth rate, feed conversion ratio, live weight, metabolisable energy intake, carcass weight, breast meat weight, abdominal fat pad weight, liver weight, heart weight, thigh weight, meat flavour, juiciness and tenderness of female Ross 308 broiler chickens. However, moringa seed meal supplementation improved (P<0.05) nitrogen retention and gizzard weights of female Ross 308 broiler chickens. vi It was concluded that moringa seed meal supplementation improved growth rate of unsexed Ross 308 broiler chickens aged one to 21 days. Similarly, moringa seed meal supplementation increased nitrogen retention and gizzard weights of female Ross 308 broiler chickens aged 22 to 42 days.

Thesis (M.A. Agricultural Management (Animal Production)) -- University of Limpopo, 2016 / A total of 320 male and female day old Ovambo and Potchefstroom koekoek (PK) chickens, were randomly assigned to a 2 (breed) × 2 (sex) factorial arrangement in a completely randomised design. Meat quality traits of male and female Ovambo and Potchefstroom Koekoek chickens were evaluated in this comparative study. The chickens were raised from day-old and fed on a commercial grower diet with 11.5 MJ/ME kg DM and 20% crude protein. The carcass traits of the Ovambo and Potchefstroom Koekoek (PK) were similar (P>0.05) except for breast yield. Sex affected on all carcass traits. Breed, sex, and time interactions influenced colour parameters of thigh and drumstick meat except redness (a*) and yellowness (b*) values of chicken breast meat. The pH varied significantly (P<0.05) between the breeds, sex and time period. The sensory evaluations of the chicken breeds were similar (P>0.05). However, tenderness of the breast meat as measured by shear force was higher for PK than that of Ovambo chickens. Fatty acid profiles of the chickens were not affected (P>0.05) by breed or sex. The ratios of n-6 and n-3 fatty acids were significantly lower in both breeds which are desirable in reducing the risk of many heart-related diseases. The information obtained from this study can assist efforts to promote production of indigenous chickens. The information also sheds some light in terms of consumer awareness for healthier meat choices. Keywords: Breed, Carcass traits, Meat colour, meat pH, Fatty acids

My diploma thesis focuses on design of air-conditioning system for chicken breeding spaces. In the background are considered general issues of air-conditioning, hatchery layout and microclimate for eggs incubation and chicken breeding. The research part is divided into two parts – Calculations and Design. The Calculations address the amount of incoming fresh air, heat loss, heat load and psychrometric calculations for summer and winter periods. The Design focuses on defining suitable diffusers and air-ducts, optimal air-conditioning unit with fans corresponding to hatchery requirements and pressure loss in ducts. The technical drawings and a list of used material are included.

(M.Sc. (Animal Production)) -- University of Limpopo, 2014 / Two experiments were conducted to determine the effect of dietary threonine level on productivity and carcass characteristics of indigenous Venda chickens. In each experiment the diets were isocaloric and isonitrogenous but with different dietary threonine levels. A complete randomized design was used in both experiments, the starter (1-7 weeks old unsexed chickens) and finisher (8-13 weeks old female chickens) experiments. The treatments were CT4 (4 g of threonine/kg DM), CT5 (5 g of threonine/kg DM), CT6 (6 g of threonine/kg DM), CT7 (7 g of threonine/kg DM) and CT8 (8 g of threonine/kg DM). A quadratic type of equation was used to determine dietary threonine levels for optimal feed intake, growth rate, feed conversion ratio, live weight, metabolisable energy intake and nitrogen retention of unsexed Venda chickens aged one to seven weeks. Dietary threonine level affected (P<0.05) feed intake, growth rate, feed conversion ratio, live weight, metabolisable energy and nitrogen retention. However, feed intake, growth rate, feed conversion ratio, live weight, metabolisable energy and nitrogen retention of indigenous Venda chickens were optimized at different dietary threonine levels of 6.218, 6.437, 6.331, 6.655, 5.979 and 6.158 g/kg DM feed, respectively. Dietary threonine level did not affect (P>0.05) mortality rate of the chickens. The treatments for the second experiment were FT4 (4 g of threonine/kg DM), FT5 (5 g of threonine/kg DM), FT6 (6 g of threonine/kg DM), FT7 (7 g of threonine/kg DM) and FT8 (8 g of threonine/kg DM). Dietary threonine level had effect (P<0.05) on feed intake, growth rate, feed conversion ratio, live weight, metabolisable energy and nitrogen retention of female Venda chickens aged eight to 13 weeks. Feed intake, growth rate, feed conversion ratio, live weight, metabolisable energy intake and nitrogen retention of chickens were optimized at dietary threonine levels of 6.054, 6.142, 6.442, 6.201, 5.72 and 6.088 g/kg DM, respectively. However, dietary threonine level had no effect (P>0.05) on pH values of crop, proventriculus, gizzard, small intestine, large intestine and caecum of female Venda chickens aged 91 days. Carcass weights of female Venda chickens were affected (P<0.05) by dietary threonine level. Carcass, breast, drumstick, thigh, gizzard and liver weights of female Venda chickens aged 91 days were optimized at dietary threonine levels of 6.183, 6.201, 5.712, 5.847, 4.820 and 6.180 g/kg DM, respectively. Dietary threonine level v had effect (P<0.05) on crude protein and threonine contents of female Venda chicken meat. Meat crude protein and threonine contents of female Venda chickens aged 91 days were optimized at dietary threonine levels of 5.9 and 5.7 g/kg DM, respectively. Dietary threonine level had no effect (P>0.05) on meat flavour, tenderness and juiciness of female Venda chickens. However, meat flavour, tenderness and juiciness of female Venda chickens aged 91 days were optimized at dietary threonine levels of 5.977, 6.103 and 5.977 g/kg DM, respectively. No chicken deaths were observed. / National Research Foundation (NRF)

Department of Animal Science / BSCAGR