|Dozier, W - AUBURN UNIV.|
|Corzo, A - MISSISSIPPI STATE UNIV.|
|Kidd, M - MISSISSIPPI STATE UNIV.|
|Tillman, P - AJINOMOTO HEARTLAND|
|Purswell, J - AUBURN UNIV.|
Submitted to: Journal of Applied Poultry Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: September 17, 2009
Publication Date: December 16, 2009
Citation: Dozier, W.A., Corzo, A., Kidd, M.T., Tillman, P.B., Purswell, J.L., Kerr, B.J. 2009. Dietary Lysine Requirements of Male Broilers From 14 to 28 Days of Age Subjected to Different Environmental Conditions. Journal of Applied Poultry Research. 18:690-698. Interpretive Summary: Lysine requirements currently recommended for broilers do not account for differences in environmental conditions, even though it is well known that differences in environmental temperatures will affect feed intake and, consequently, the propensity of a growing broiler to grow. In this experiment, 2 groups of broilers were grown in hot (July) or neutral (October) temperatures to assess the impact of environmental temperature on digestible lysine requirements. Data presented indicated that the dietary lysine requirement varied considerably, differing by 9%, with broilers reared in different environmental temperatures. This information is important for nutritionists at broiler production companies who are responsible for formulating diets to optimize broiler performance in the most economical manner.
Technical Abstract: Dietary amino acid requirements are influenced by environmental conditions. Two experiments examined growth responses of Ross × Ross TP 16 male broilers fed diets varying in digestible (dig) Lys concentrations from 14 to 28 days of age under different environmental conditions. Experiment 1 was conducted in July 2007, whereas Experiment 2 was initiated during October 2007. In each experiment, dietary treatments consisted of 6 concentrations of dig Lys and a positive control. Digestible Lys ranged from 0.90 to 1.25% in increments of 0.07%, and from 0.92 to 1.32% in increments of 0.08%, for Experiment 1 and 2, respectively. Linear and quadratic improvements were observed for BW gain and feed conversion in Experiment 1 and 2, respectively. In Experiment 2, dig Lys requirement was estimated at 1.19% based on quadratic broken-line model and quadratic regression equation. Digestible Lys intakes that corresponded to the optimum dig Lys response based on a dietary percentage were estimated at 1,280 and 1,404 mg/day for Experiment 1 and 2, respectively. These results suggest the dietary Lys need varied considerably with broilers reared in environmental conditions emulating winter vs. summer production when expressed on a dig Lys intake basis.