Broiler production is an important animal production enterprise with potential to make high returns. Increasing feed efficiency and early body weight gain has always been a top priority in the broiler industry. The general objective of broiler nutrition is to maximise production performance and profitability . Nutrition is of major importance in raising chicken, and feed is a major input in poultry production systems, accounting for over 60% of total production costs in commercial poultry sector Renkema (1992). The cost of feed is therefore often a constraint especially in developing countries. For instance, Onyenokwe (1994) observed that high cost of feed ingredients in many African countries has caused many poultry farmers to abandon the industry. The continued rise in feed prices is due to competition for some of the ingredients with human e.g. sorghum, wheat and maize. Broiler farmers are therefore forced to use combinations of feed ingredients of low cost to obtain savings and avoid any further loss of profits. It is therefore important to give special attention to feed and feeding since the rate of feed consumption increases rapidly with advancing age of the birds and good nutrition is reflected in the bird's performance and its products. The profitability of a broiler enterprise depends on the efficient conversion of feed to meat. Broilers have the ability to convert the feeds into meat with a high efficiency. For instance Morris and Njuru (1990) reported that broilers have much higher daily rates of protein deposition than layer chicken strains. This implies that fast-growing strains would require greater daily protein intakes than slow-growing ones. In the past, the major criteria for assessing the performance of broilers has been growth rate and feed conversion ratio (FeR). Diet specifications and feeding programmes have been aimed at maximising these two parameters whereby overall flock performance is calculated based on the total weight of chicken produced from total feed deliveries. With the new developments in understanding of nutritional factors affecting broiler growth and carcass composition, it is now possible to apply sophisticated and yet efficient approaches to feeding broilers. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2005.

Two identical experiments were conducted to evaluate the combined effects of arginine (AR), vitamin E (VE) and vitamin C (VC) on cardiopulmonary performance and ascites parameters of broilers reared under cold environmental temperature. One d old male broilers were fed a basal corn-soybean meal diet (CTL, 1.2 % AR and 40 IU VE), the basal diet supplemented with 1% AR and either 200 IU VE (AE group), or 500 mg of VC (AC group), or a combination of VE and VC (AEC group) at the same level per kg of feed. Pulmonary arterial pressure (PAP) and mean arterial pressure (MAP) were recorded in clinically healthy anesthetized birds (28-42 d old) before and after an epinephrine challenge (EPI, 0.5 mg/kg BW i.v.), Amino-guanidine Hemisulphate (AG, 100 mg/kg BW i.v.) and N-Nitro L-Arginine Methyl Ester (L-NAME 50 mg/kg BW, i.v.) at 20 min intervals. The PAP increased 30 s after EPI in all birds, but the peak PAP was lower in the AEC group than in all the other birds. After 120 s of challenge the PAP was lower in AEC birds compared to the other birds. The PAP returned to pre-EPI levels within 300 s in all groups. The PAP was increased ( P< 0.05) within 60 s after the AG and L-NAME challenge in all groups, but no differences were found among groups. Plasma nitric oxide (NO) was higher in the AEC birds than in all the other groups before and after challenge. Our results showed that birds fed AEC maintained a lower PAP than the CTL birds after EPI elicited an increase in cardiac output and this can be explained by a higher production of NO. A combination of AR, VE, and VC may have complementary effects against oxidative stress, protecting the endothelium and preserving NO function.

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The high cost of feed materials and feed additives in developing nations has elicited interest in the search for sustainable alternatives. Moringa (Moringa oleifera), one of such sustainable alternatives is a tropical plant that has its usefulness investigated in this study. A 42-day study was designed to determine the response of Ross 308 broilers to dietary Moringa oleifera leaf meal supplementation. The Moringa oleifera leaves used for the study were analysed for proximate, mineral and composition as well as phytochemical contents before being incorporated in the diet. Day-old Ross 308 broiler chicks (n = 500) were allotted to five treatments in completely randomized design with each treatment replicated five times and each replicate having 20 chicks. The birds were subjected to diets supplemented with Moringa oleifera leaf meal at 0, 25, 50, 75 and 100 g/kg feed at both starter and finisher stage, respectively and designated as T1, T2, T3, T4 and T5. Moringa oleifera leaf meal level that supported optimum production and physiological variables was modelled using the quadratic function. At day 42, three birds per replicate were slaughtered to evaluate carcass and organ yields. Result of the proximate composition revealed that MOLM is rich in protein (32.37%) and neutral detergent fibre (52.16%). Mineral assay indicated that MOLM was high in calcium, sodium, potassium, sulphur and iron. Daily feed intake (FI), average daily gain (ADG) and feed conversion ratio were the same among the treatments with the exception of starter broilers on diet T1 that had higher ADG (p<0.05) than those on the other diets. Final live weight (FLW), mortality and gizzard weight were influenced (p<0.05) by Moringa oleifera leaf meal supplementation. Moringa oleifera leaf meal supplementation had no effect on parameters measured. Moringa oleifera leaf meal supplementation at 39.98 and 35.80 g/kg feed supported optimum FLW and ADG at starter phase and 46.88 g/kg feed MOLM supported optimum FLW at finisher phase. In conclusion, Moringa oleifera leaf meal is a good source of nutrients and suitable for production of enhanced cut parts in broiler chickens. Birds on 50 and 75 g Moringa oleifera leaf meal/kg feed had higher (p<0.05) packed cell volume (PCV), red blood cell (RBC) and glucose than those on the other 3 treatment diets. The white blood cell (WBC) counts for birds on 50 g Moringa oleifera leaf meal/kg feed were higher (p<0.05) than those on 100 g Moringa oleifera leaf meal/kg feed but similar (p>0.05) to those on 0, 25 and 75 g MOLM/kg feed. Blood platelet count maintained the trend 75 g > 0 g > 50 g > 100 g > 25 g MOLM/kg feed with birds on 75 g Moringa oleifera leaf meal/kg feed being statistically higher (p<0.05) than those on 25, 50 and 100 g MOLM/kg feed. Dietary Moringa oleifera leaf meal supplementation had no significant effect (p>0.05) on haemoglobin (Hb), total serum protein (TSP), albumin, cholesterol and uric acid. Triglyceride (TG) level of birds on 25, 75 and 100 g Moringa oleifera leaf meal/kg feed decreased significantly compared to those on 0 and 50 g MOLM/kg feed. Daily Moringa oleifera leaf meal supplementation had a significant effect (p<0.05) on the differential WBC count. Daily Moringa oleifera leaf meal supplementation with 26.99 g/kg feed and 31.95 g/kg feed respectively supported optimum PCV (38.62%) and glucose (245.42 mg/dl) in Ross 308 broilers. It is, therefore summarized that optimizing MOLM supplementation level in the ration of Ross 308 broilers could assist in improving their productivity. / Agriculture and  Animal Health / Ph. D. (Agriculture)

The aim of this study was to evaluate the effects of broiler maternal dietary lysine intake on progeny performance. Three experiments were conducted with chicks hatched from Cobb 500 breeders at 38, 48, and 60 weeks of age. Breeder hens received six dietary treatments (T1-T6) from 26 to 60 weeks of age, which allowed an intake of 800, 930, 1070, and 1200 mg lysine/bird/d (T1-T4) respectively. An intake of 800 mg/bird/d at 26 weeks was increased by 25 mg every two weeks to provide 1225 mg lysine/bird/d at 60 weeks (T5). An intake of 1200 mg/bird/d at 26 weeks was reduced by 25 mg every two weeks to supply 775 mg lysine/bird/d at 60 weeks (T6). A total of 320, 401, and 390 chicks were hatched from breeder hens at 38, 48, and 60 weeks of age respectively. Immediately after hatching, 270, 384, and 384 unsexed chicks from breeder hens at 38, 48 and 60 weeks of age respectively, were placed in an environmentally controlled room and randomly allocated (within a treatment) to single-tier cages (80 × 50 cm). Nine chicks from breeders at 38 weeks of age and 8 chicks from breeders at 48 and 60 weeks of age were placed in each pen, keeping chicks from the same treatment group together for 21 d. Chicks were fed ad libitum with a commercial broiler starter crumble for 21 d and water was provided ad libitum throughout the duration of each trial. Feed intakes (FI), body weight gain (BWG) and feed conversion ratio (FCR) were measured weekly. Data were subjected to analysis of variance using a generalized linear model of GenStat 12th edition. Simple linear regression model of GenStat 12th edition was used where appropriate. Significant improvements in offspring feed intake and body weight gain from 7-21 d were observed in chicks hatched from young breeder flocks (38 weeks) with low dietary lysine intakes (800, 930 and 950 mg/bird/d). The effect of maternal dietary lysine intake on offspring performance disappeared with the aging of the breeder flock (60 weeks). It was concluded that lower maternal dietary lysine intakes (800, 930 and 950 mg/bird/d) may improve feed intake and body weight gain from 7-21 d of broiler chicks hatched from younger breeder flocks (38 weeks). / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2011.

The increased demand for breast meat of broiler chickens has challenged researchers to investigate management techniques that could be used to increase the production of this valuable commodity. Two experiments were conducted in this study; the first investigated the effect of early feeding of newly hatched broilers on breast meat yield (BMY) at market weight, and the second focused on improving BMY of broilers exposed to short daylengths by feeding higher than conventional levels of dietary protein. In the first experiment, of the 528 eggs set in the incubator, half were placed, at day 18, in hatching trays containing a commercial broiler starter feed whilst the others (the held group) were hatched conventionally. Six chicks from both fed and held groups were sampled at nine-hour intervals from the time that the first chicks hatched for a subsequent period of 36 h. After measuring their body weight these chicks were euthanised and dissected in order to measure their breast and yolk weights. Body protein, lipid and water contents were measured on each chick. At day 21, six birds from the fed and held groups were sampled, and body weight, breast weight and body protein content were measured. The yolk sac weight for fed birds was significantly reduced compared to that of held birds (P < 0.001). Both fed and held birds had the same breast weight at hatch, but at day 21 the mean breast weight of the fed birds was significantly heavier than of held birds (P < 0.05). The birds that were removed first from the hatcher had a reduced breast muscle weight compared to those that were removed last. In the second experiment, a total of 3200 day-old broiler chicks were reared in eight light-tight rooms. Four lighting regimens (12L: 12D, 16L: 8D, 20L: 4D and 24L: 0D) were randomised between rooms, with each light treatment being replicated twice. Each room was divided into four pens and 100 chicks in each pen received one of four dietary protein treatments. At day 35, three birds from each pen were sacrificed so that measurements could be made of breast, thigh, drum and wing weight, and carcass chemical composition. Breast weight increased as daylengths increased except in birds that were fed low protein diet (143 g protein/kg feed). High levels of dietary protein increased breast weight in birds on all other daylengths except for those on 12 h which showed a reduced breast muscle weight when dietary protein content was increased. The results of the first trial suggests that breast meat yield could be improved if newly hatched chicks are offered feed immediately after hatch, however the hypothesis that this increment was due to an overall increase in body protein content in the first few days after hatching could not be corroborated. The results further showed that held birds do not withdraw nutrients from breast muscle to maintain growth at hatch, this is because birds that stayed longer in the hatchery without feed showed increased breast muscle weight compared to those that were removed first. The second trial could not identify a suitable feeding programme to overcome the problem of a lower breast muscle weight that results from the use of 12 h of lighting compared to that when long daylengths are used. Highest breast weight was obtained when birds were fed high protein diet at 20 h. More research is required to further investigate the combined effect of early feeding and daylength on breast meat yield in broiler chickens. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2012.

Thesis (M. Sc. Agriculture (Animal Production)) -- University of Limpopo, 2019 / Two experiments were conducted to determine the effect of dietary methionine level on productivity and carcass characteristics of Ross 308 broiler chickens. In each experiment, the diets were isocaloric and isonitrogenous but with different dietary methionine levels. Five diets were formulated to contain dietary methionine levels of 4, 5, 6, 8 or 9g/kg DM. The first experiment commenced with 300 unsexed Ross 308 broiler chickens with initial average live weights of 42 ± 2g per chicken. The chickens were randomly assigned to five treatments with five replications, resulting in 25-floor pens with 12 chickens per replicate. The second experiment commenced with 150 male Ross 308 broiler chickens with initial average live weight of 637 ± 12g per chicken. The chickens were randomly assigned to five treatments with three replications, resulting in 15-floor pens with 10 chickens per replicate. A complete randomized design was used in each experiment. Data was analysed using the General Linear Model (GLM) procedures of the statistical analysis of variance, Version 9.3.1 software program. Where there were significant differences, mean separation was done using the Tukey test at the 5% level of significance. A quadratic regression model was used to determine the optimal productivity of the chickens while a linear model was used to determine the relationships between dietary methionine level and responses by the chickens in the variables measured. The treatments for the first experiment were UM4 (4g methionine/kg DM), UM5 (5g methionine/kg DM), UM6 (6g methionine/kg DM), UM8 (8g methionine/kg DM) and UM9 (9g methionine/kg DM). Feed intake, growth rate, feed conversion ratio (FCR), metabolisable energy intake and nitrogen retention of unsexed Ross 308 broiler chickens aged one to 21 days were not affected (P>0.05) by dietary methionine level. Similarly, dietary methionine level did not have any effect (P>0.05) on diet crude protein (CP), acid detergent fibre (ADF), neutral detergent fibre (NDF) and fat digestibilities in unsexed Ross 308 broiler chickens aged 14 to 21 days. Dietary methionine level did not have any effect on live weights of broiler chickens at 21 days. Live weights of unsexed Ross 308 broiler chickens aged 7 or 14 days were not improved (P>0.05) by increasing dietary methionine level from 4 to 9g/kg DM. Crop, gizzard and small intestine weights and crop, proventriculus and gizzard digesta pH values of unsexed Ross 308 broiler chickens aged 21 days were not affected v (P>0.05) by dietary methionine level. Similarly, dietary methionine level did not improve (P>0.05) caecum and large intestine lengths of unsexed Ross 308 broiler chickens aged 21 days. However, dietary methionine level affected (P<0.05) dry matter (DM) and ash digestibilities of unsexed Ross 308 broiler chickens aged 14 to 21 days. Proventriculus and large intestine weights, gastrointestinal tract and small intestine lengths of unsexed Ross 308 broiler chickens aged 21 days were improved (P<0.05) by increasing dietary methionine level. In addition, increasing dietary methionine level increased (P<0.05) small and large intestine digesta pH values of broiler chickens aged 21 days. Thus, dry matter digestibility, live weights at day 7 ad 14, caecum length, large intestine length and digesta pH were optimized at different dietary methionine levels of 7.26, 5.29, 4.99, 6.80, 4.84 and 6.37g/kg DM feed, respectively. The treatments for the second experiment were MM4 (4g methionine/kg DM), MM5 (5g methionine/kg DM), MM6 (6g methionine/kg DM), MM8 (8g methionine/kg DM) and MM9 (9g methionine/kg DM). Dietary methionine level did not have effect (P>0.05) on feed intake of male Ross 308 broiler chickens aged 6 weeks. However, dietary methionine level improved (P<0.05) feed intake of male Ross 308 broiler chickens aged 4 or 5 weeks. Live weights of male Ross 308 broiler chickens aged 28 days were not affected (P>0.05) by dietary methionine level. However, live weights of male Ross 308 broiler chickens aged 35 and 42 days were affected (P<0.05) by dietary methionine level. Similarly, dietary methionine level affected (P<0.05) DM, CP, ADF, NDF, fat and ash digestibilities of male Ross 308 broiler chickens aged 35 to 42 days. Thus, dietary methionine levels of 6.93, 7.70, 6.85 and 11.27g/kg DM optimized dry matter, CP and fat digestibilities, and live weight of male broiler chickens aged 42 days. Dietary methionine level did not affect (P>0.05) FCR, growth rate and metabolisable energy intakes of male Ross 308 broiler chickens. Increasing dietary methionine level from 4 to 9g/kg DM improved (P<0.05) nitrogen retention of male Ross 308 broiler chickens aged 22 to 42 days. Dietary methionine level did not have any effect (P>0.05) on proventriculus, gizzard, caecum and large intestine weights, caecum, small and large intestine lengths, and crop, gizzard, caecum and large intestine digesta pH values of male Ross 308 broiler chickens aged 42 days. Crop and small vi intestine weights and gastrointestinal tract lengths of male Ross 308 broiler chickens aged 42 days were improved (P<0.05) by dietary methionine level. Similarly, dietary methionine level affected (P<0.05) proventriculus and small intestine digesta pH values of male Ross 308 broiler chickens aged 42 days. Thus, dietary methionine levels of 6.558 and 7.851g/kg DM optimized broiler chicken crop weight and GIT length. Dietary methionine level affected (P<0.05) carcass organ weights of male Ross 308 broiler chickens aged 42 days. Increasing dietary methionine level increased chicken breast meat weight. However, there was no clear trend for the other carcass organs. Meat flavour and shear force values of male Ross 308 broiler chickens aged 42 days were not affected (P>0.05) by dietary methionine level. However, dietary methionine level affected meat tenderness and juiciness. Thus, dietary methionine levels of 10.09 and 13.32g/kg DM optimized broiler chicken meat tenderness and juiciness. . / National Research Foundation (NRF) and VLIROUS

Call number: LD2668 .T4 1985 Z58 / Master of Science

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.