Effect of Four Dietary Lysine Concentration on Body Weight Gain of Broiler Breeders (29-50 weeks of age) Kept at Four Different Temperatures

Abstract

Broiler breeders have a much greater body weight in relation to their egg output; also they are restrictedly fed in commercial practice. These differences with egg laying strains could result in significant differences in response. The specific objectives of the experiment were first to examine and explain the effects of four different ambient temperatures 21, 26, 29 and 32oC on the response of the breeders body weight gain. Second, to examine their response of four dietary lysine concentrations (35, 50, 65 and 90 g/kg crude protein). Third, to examine whether there were temperature x lysine concentration interaction in the responses of broiler breeders. 224 (308 Ross Breeder) at 29 week old hens were randomly allocated to 16 identical pens within eight controlled rooms. Two male birds were chosen at random and also placed in each pen. Single wheat based, lysine deficient diet that contained 151 g/kg CP was formulated. The body weight change of each pen of birds was recorded at the end of each period and expressed as g/bird day. A split-plot design was used in which four main plots (rooms). Throughout the experiment the allocated amounts of feed were always eaten. Male body weight gain was decreased linearly (P<0.001) by increasing temperature, but not (P>0.05) for female body weight gain. There were no significant differences (P>0.05) between the different lysine concentration levels in body weight gain, similarly there were no consistent (P>0.05) temperature x lysine concentration interactions.