E. Erwan, A.R. Alimon, A.Q. Sazili, H. Yaakub and M. Hilmi
American Journal of Animal and Veterinary Sciences, 2009, 4(4), 95-100.
Problem statement: Supplementation of broiler diets with cristalline amino acids (i.e. lysine, ethionine and threonine) may support equal broiler growth and improve overall amino acids balance and enable a reduction in CP level of diets. Approach: A trial was conducted to evaluate the effect of supplemental L-leucine in diets containing recommended levels and low crude protein (20 and 18%, respectively) with constant metabolizable energy (3200 kcal kg-1) for broilers from 21-42 day of age. Six experimental diets were formulated with three levels of supplemental L-leucine, 0, 0.5 and 0.67% and two levels of crude protein. A total of 180 1 day-old Cobb broiler chickens were randomly divided into 36 experimental pens, 5 chickens in each pen, with each diet replicated 6 times. The dietary treatments were offered from 21-42 days of age. Feed intake, body weight gain and Feed Conversion Ratio (FCR) were measured on a weekly basis. At the end of the feeding trial the birds were slaughtered and carcass analyses conducted. Results: Feed intake, weight gain and FCR were not affected by increasing levels of L-leucine supplementation. Weight gain was significantly reduced (p<0.05), whereas feed intake and FCR were not significantly affected with decreasing dietary crude protein. A positive response in breast meat yield was achieved by the addition of L-leucine to levels up to 0.5% in the diet but a significant decrease was noted when the level reached 0.67% in diet. Supplementation of L-leucine significantly (p<0.05) decreased the relative weights of the liver and gizzard. However, the addition of L-leucine significantly reduced carcass weights when L-leucine was added at 0.67%. Lowering the dietary protein level also significantly reduced breast yield and carcass weight (p<0.05). However, abdominal fat, gizzard, liver and heart were not affected by protein level. Conclusion/Recommendations: It can be concluded that supplementation of L-leucine at levels up to 0.67% of the diet did not affect performance but deleteratious the carcass weight.
American Journal of Animal and Veterinary Sciences, 2008, 3(3), 78-84.Effects of Betaine Supplementation to Methionine Deficient Diet on Growth Performance and Carcass Characteristics of Broilers
American Journal of Animal and Veterinary Sciences, 2008, 3(3), 78-84.Application of Meal Feeding and Skip-A-Day Feeding With or Without Probiotics for Broiler Chickens Grown at High-Altitude to Prevent Ascites Mortality
American Journal of Animal and Veterinary Sciences, 2010, 5(1), 13-19. DOI: 10.3844/ajavsp.2010.13.19Change in Growth Performance and Liver Function Enzymes of Broiler Chickens Challenged with Infectious Bursal Disease Virus to Dietary Supplementation of Methionine and Threonine
American Journal of Animal and Veterinary Sciences, 2010, 5(1), 20-26. DOI: 10.3844/ajavsp.2010.20.26Effects of Betaine Supplementation to Methionine Deficient Diet on Growth Performance and Carcass Characteristics of Broilers
American Journal of Animal and Veterinary Sciences, 2008, 3(3), 78-84.Effects of Enzyme Supplementation on Performance, Carcass characteristics, Carcass Composition and Some Blood Parameters of Broiler Chicken
American Journal of Animal and Veterinary Sciences, 2010, 5(3), 221-227. DOI: 10.3844/ajavsp.2010.221.227