Effect of dietary methionine to crude protein ratio on performance of Ross 308 broiler chickens aged 22 to 42 days.

An experiment was conducted to determine the effect of dietary methionine to crude protein (CP) ratio on the performance of male Ross 308 broiler chickens aged 22 to 42 days. The diets were isocaloric and isonitrogenous but with different methionine-to-CP ratios. The diets, based on methionine to crude protein ratios, were M0.020 (0.020), M0.025 (0.025) M0.030 (0.030), M0.040 (0.040), or M0.045 (0.045). A complete randomized design was used. A quadratic type of equation was used to determine dietary methionine to CP ratios for optimal performance of the chickens. Dietary methionine to CP ratio had no effect (P > 0.05) on feed intake, live weight gain, live weight, feed efficiency, metabolizable energy intake, nitrogen retention, abdominal fat pad weight, breast meat nitrogen and methionine contents, and meat flavour and shear force values of the chickens, but it affected (P < 0.05) CP digestibility, carcass and breast weights, and breast meat tenderness and juiciness. Methionine to CP ratios of 0.039, 0.038, 0.050, and 0.050 were calculated to result in optimal CP digestibility, carcass weight, breast meat tenderness, and juiciness, respectively. These results may imply that dietary methionine to CP ratio requirements for broiler chickens will depend on the production parameter of interest.

Effects of bee pollen inclusion on performance and carcass characteristics of broiler chickens.

This study was conducted to determine the effect of bee pollen (BP) inclusion on performance and carcass characteristics in broiler chickens. A total of 240 Ross 308 broiler chicks were allocated to 4 treatments (BP inclusion levels of 0, 4, 8, or 12 g/kg DM feed) in a randomized complete block design with sex as a block having 3 replicates with 10 chickens per replicate. After 21 d, the chickens remained in their treatment groups and fed standard grower diet. The results of the current study revealed that BP inclusion had positively improved (P < 0.05) average weekly feed intake (FI), body weight (BW), body weight gain (BWG), and feed conversion ratio (FCR) in both sexes. However, the apparent nutrient digestibility, metabolizable energy (ME), and nutrient digestibility were not affected by the dietary BP. Furthermore, carcass yield in both sexes was improved (P < 0.05) by BP inclusion levels. In contrast, meat pH, shear force, and sensory evaluation in both sexes were not affected (P > 0.05). The results suggest that the broiler chicks can utilize bioactive compounds in BP when supplemented in the starter diets and subsequently improve their growth parameters throughout the growing period as well as carcass yield at slaughter age. These positive improvements could be due to high quality amino acids, essential oils, vitamins, and minerals of BP. Therefore, it is concluded that BP inclusion level of 12 g/kg or more in the starter diets could have positive effects on growth performance and carcass yield at slaughter age without causing adverse effects on meat physico-chemical properties and sensory evaluation in both male and female broiler chickens.

Dietary Crude Fiber Levels for Optimal Productivity of Male Ross 308 Broiler and Venda Chickens Aged 1 to 42 Days.

The study determined the effects of dietary crude fiber (CF) levels on the production performance of male Ross 308 broiler and indigenous Venda chickens. There were 360 male Ross 308 broiler and male Venda chickens aged 1-21 for Phase 1 and 196 chickens aged 22-42 days for Phase 2. Chickens were allocated four diets with different levels of CF (3, 4, 5, and 7%) in a completely randomized design. Quadratic regression analyses were used to determine the dietary CF levels for the optimal production responses. In Phase 1, the feed intake, growth, live weight, nitrogen retention, and metabilizable energy (ME) intake of the Ross 308 broiler chickens were improved at dietary CF levels of 3.9, 4.5, 4.5, 3.2, and 3.7%, respectively. In the Venda chickens, feed intake, growth, live weight, nitrogen retention, and ME intake were optimized at 4.4, 4.8, 4.7, 4.1, and 3.3% CF, respectively. In Phase 2, the feed intake, nitrogen retention, and neutral detergent fiber digestibility (NDFD) were enhanced at CF levels of 6.4, 4.4, and 3.7% in the Ross 308 broiler chickens, respectively. Dietary CF levels of 4.5, 5.8, 5.7, 5.1, 3.9, and 4.4% optimized the feed intake, growth rate, live weight, nitrogen retention, NDF, and ADFD, respectively, in Venda chickens. It was concluded that the indigenous Venda chickens coped better with higher dietary CF than the Ross 308 broiler chickens.

The Influence of Different Amaranth Leaf Meal Inclusion Levels on Performance, Blood Profiles, and Gut Organ Characteristics of Ross 308 Broiler Chickens.

This study aimed to determine the effect of varying inclusion levels of amaranth leaf meal on the performance, blood profiles, and gut organ characteristics of Ross 308 broiler chickens. A total of 200, day-old, Ross 308 broiler chicks were randomly allocated to five dietary treatments in a complete randomized design, with each group having four replicates with ten chicks. Amaranth leaf meal (ALM) inclusion levels used in this study were 0, 5, 10, 15, and 20%. Body weight and feed intake were measured weekly to calculate the feed conversion ratio. Gut organ weights, lengths, organ pH, and blood profiles were measured and the general linear model of statistical analysis software was used to analyze collected data. ALM had no effect (p > 0.05) on feed intake, body weight, or the feed conversion ratio of Ross 308 broiler chickens between 1-21 and 22-42 days, respectively. Furthermore, ALM inclusion levels had no effect (p > 0.05) on dry matter (DM) or gross energy (GE) digestibility of Ross 308 broiler chickens. Ross 308 broiler chickens, which were fed with 5% ALM inclusion levels, had higher (p < 0.05) white blood cells, lymphocytes, and eosinophils than those fed with diets containing 0, 10, 15, and 20%. Chickens that were fed with 0 and 20% ALM inclusion levels had higher (p < 0.05) heterophils than those fed with diets containing 5, 10, and 15%. Chickens that were fed with 15% ALM inclusion levels had higher (p < 0.05) monocytes, eosinophils, and basophils than those fed with diets containing 0, 10, and 20%. Apart from Ile, ALM inclusion of 5 and 10% had higher (p < 0.05) essential and nonessential amino acid digestibility in Ross 308 broiler chickens. ALM inclusion levels had no effect (p > 0.05) on gut organ lengths or weights of Ross 308 broiler chickens aged 21 and 42 days. In conclusion, 5, 10, and 15% ALM inclusion levels can be included in broiler chicken diets as they showed favor in most of the affected parameters.

Chemical Composition and Metabolomic Analysis of Amaranthus cruentus Grains Harvested at Different Stages.

This study aimed at investigating the impact of early versus normal grain harvesting on the chemical composition and secondary metabolites of Amaranthus cruentus species grown in South Africa. Mature harvested grain had higher (p < 0.05) DM, CF, NDF and ADF content compared to prematurely harvested grain. There were no significant (p > 0.05) differences between CP, ADL and GE of premature and mature harvested grains. Mature harvesting resulted in higher grain Ca, P, Mg and K content. Essential amino acids spectrum and content remained similar regardless of maturity at harvest. The grains displayed an ample amount of unsaturated fatty acids; the highest percentage was linoleic acid: 38.75% and 39.74% in premature and mature grains, respectively. ß-Tocotrienol was detected at 5.92 and 9.67 mg/kg in premature and mature grains, respectively. The lowest was δ-tocotrienol which was 0.01 and 0.54 mg/kg in premature and mature grains, respectively. Mature harvested grain had a higher secondary metabolite content compared to premature harvested grains. The results suggest that mature harvested Amaranthus cruentus grain contain more minerals and phytochemicals that have health benefits for human and livestock immunity and gut function, which ultimately improves performance. This study concludes that A. cruentus grown in South Africa is a potential alternative cereal to major conventional cereals.

Breeding practices and trait preferences of goat keepers at Lepelle-Nkumpi Local Municipality, South Africa: implication for the design of breeding programmes.

Identification of breeding practices and trait preferences by livestock keepers for the selection of breeding animals to be parents of the next generations is the crucial step to the successful implementation of community-based breeding program (CBBPs). The study aimed to detect breeding practices and trait preferences by farmers at Lepelle-Nkumpi Local Municipality, South Africa to determine their relevance in establishing a CBBP. A well-structured questionnaire was designed and administered to 183 randomly selected goat keepers from four villages. Chi-square statistics were used to compare categorical variables among villages. Socio-economic factors and reasons for keeping goats were not significantly different (P > 0.05) between the four villages. Methods of controlling mating, reasons for not controlling mating, keeping breeding bucks, source of breeding bucks, reasons for culling, and culling methods were significantly different (P < 0.05) among villages. The most common trait preferences of goat keepers among the surveyed villages were twinning ability, mothering ability, and body size in breeding does, while in breeding bucks were mating ability, growth rate, and body size. The results from this study are useful for designing CBBPs for goat production in the communal areas of Lepelle-Nkumpi Local Municipality.

Effect of polyethylene glycol 4000 supplementation on the performance of yearling male Pedi goats fed dietary mixture levels of Acacia karroo leaf meal and Setaria verticillata grass hay.

Eighteen yearling male Pedi goats weighing 21.7 ± 3.1 kg were used in a 42-day trial in a 2 (Acacia karroo leaf meal levels) × 3 (levels of PEG 4000) factorial arrangement in a completely randomized design to determine PEG 4000 supplementation levels for optimal productivity of indigenous Pedi goats fed different mixture levels of A. karroo leaf meal and Setaria verticillata (L.) P.Beauv. grass hay. Each goat was supplemented with 0, 23 or 30 g of PEG 4000 per day in addition to dietary mixture of A. karroo and S. verticillata hay. Polyethylene glycol 4000 supplementation had no effect (P > 0.05) on nutrient intake of goats. However, a diet × PEG (P < 0.05) was observed for intake of all nutrients studied. Dry matter, OM, NDF and ADF intakes per goat were optimized at PEG 4000 supplementation levels of 19.62, 19.62, 19.61 and 19.53 g/goat/day, respectively, for diets containing 20% A. karroo leaf meal. Polyethylene glycol 4000 supplementation had no effect (P > 0.05) on the apparent digestibility of all nutrients. The dietary inclusion level of A. karroo leaf meal at 20% improved (P < 0.05) DM, OM, CP, NDF and ADF digestibility of goats. Crude protein digestibility was optimized at a PEG 4000 supplementation level of 15.78 g/goat/day. Dietary mixture level and PEG 4000 supplementation had no effect (P > 0.05) on final weights of Pedi goats. Similar results were observed for blood urea and glucose concentrations of yearling male Pedi goats. However, daily body weight gain was higher (P < 0.05) in goats fed 50% A. karroo leaf meal than those on 20% inclusion level. Polyethylene glycol 4000 has potential to improve the feeding value of tanninifeorus A. karroo leaf meal.

Effects of urea-treated fibrous diets on nutrient intake, digestibility, performance and haematological parameters of Yankasa rams.

An experiment was conducted to investigate the effects of urea-treated fibrous diets on the intake, nutrient digestibility, performance and haematological parameters of Yankasa rams. A total of 48 Yankasa rams (BW 10.00 ± 1.50 kg; 6-8 months old) were allocated into four treatment groups in a completely randomised design (12 rams per treatment). Animals were placed on complete rations of yam peels, maize bran and rice husk treated with 0, 1.0, 1.5 or 2.0% urea. The experiment lasted for 18 weeks. Yankasa rams fed with urea-treated diets had higher feed intake (949.88 and 938.04 g/day for U15 and U20, respectively), daily weight gain (227.67 and 181.00 g/day for U15 and U20, respectively) and better feed conversion ratio (4.17 and 5.18 for U15 and U20, respectively). Rams on urea-treated diets had higher haemoglobin and red blood cell contents and higher weight gains, indicating that urea treatment enhanced nutrient supply and utilisation at the tissue level. It was concluded that urea treatment of fibrous farm by-products is a promising feeding strategy especially during the dry season when there is scarcity of high-quality forages. Addition of 1.5% urea to roughage diets and farm by-products to form a total mixed ration may preclude the search for supplements.

Effect of dietary ascorbic acid supplementation level on productivity, mortality, and carcass characteristics of Venda chickens.

Two experiments were carried out to determine the effect of dietary ascorbic acid supplementation levels on productivity, carcass characteristics, and mortality of indigenous Venda chickens. The first experiment determined the effect of dietary ascorbic acid supplementation levels on productivity and mortality rate of 175 unsexed Venda chickens between 1 and 6 weeks old. The second experiment determined the effect of dietary ascorbic acid supplementation levels on productivity, carcass characteristics, and mortality rate of 140 female Venda chickens between 8 and 13 weeks old. A completely randomized design was used in both experiments. Supplementation of grower diets with ascorbic acid ranged from 0 to 2,000 mg per kg DM feed in both experiments. Levels of ascorbic acid supplementation for optimum feed intake, feed conversion ratio, growth rate, live weight, and breast meat yield were determined using a quadratic equation. The optimal dietary ascorbic acid supplementation levels for feed conversion ratio, growth rate, and live weight of Venda chickens during the starter phase were 1,050, 1,301, and 1,500 mg/kg DM feed, while, at the grower phase, the optimal supplementation levels for feed conversion ratio, growth rate, live weight, and breast meat yield were 1,000, 1,250, 1,482, and 769 mg/kg DM feed, respectively. Results indicate that different levels of ascorbic acid supplementation optimized feed conversion ratio, growth rate, and live weight of Venda chickens at each growth phase. However, levels of ascorbic acid supplementation for optimum feed conversion ratio, growth rate, and live weight were higher than that for breast meat yield. These findings have implications on ration formulation for Venda chickens.