|Dozier Iii, William|
Submitted to: Southern Poultry Science Society Meeting Abstracts
Publication Type: Proceedings
Publication Acceptance Date: 10/30/2004
Publication Date: 1/15/2005
Citation: Kidd, M.T., Corzo, A., Dozier III, W.A., Miller, E.R., Hoehler, D. 2005. Broiler response to amino acid density in a digestible ideal pattern during various feed phases throughout life. Southern Poultry Science Society Meeting. Abstract 101. p. 25.
Technical Abstract: Dietary amino acid patterns dictate white meat yield in broilers. As genetic advances in tissue accretion and growth rate of high-yield broilers are realized, it is important to know the level and time period of amino acid optimization to coincide with feed intake patterns. Growth and carcass responses were evaluated in Ross x Ross 708 broilers. Male and female broilers (2,592, placed sex separate) were randomized across 144 floor pens containing 18 birds per pen. Dietary treatments consisted of moderate (M) amino acid density representing commercial US conditions and high (H) amino acid density based on an ideal pattern. Diets were fed to broilers from 1 to 5, 6 to 14, 15 to 35, 36 to 44, and 45 to 55 d. Diets were steam pelleted and based on corn, soybean meal, and poultry meal. Combinations of M and H diets across the five feeding phases resulted in the following treatments: (1, HHHHH; 2, HHHHM; 3, HHHMM; 4, HHMMM; 5, HMMMM; 6, MMMMM) resulting in a 2 (sex) x 6 (diet) factorial design with 12 replications per treatment. Live performance responses were measured by period. At 35 and 55 d, 4 birds per pen were randomly selected for processing. Interactions (P < 0.05) occurred for 1 to 5 d BW and feed conversion (FC) indicating that female BW, but not male BW, responded positively to H diets whereas male FC, but not female FC, was improved with H diets. At 55 d, male broilers were heavier (P < 0.05) and had lower FC (P < 0.05; 5 points) than female broilers. Optimal BW and FC (P < 0.05) occurred by feeding H diets to d 35 and d 55, respectively. Carcass and breast meat yields followed the same pattern (P < 0.05) as BW indicating the importance of H amino acid density to d 35. Based on performance criteria in the various feeding phases, different scenarios were calculated in order to maximize economics of broiler production.