|DE BEER, M|
Submitted to: Meeting Abstract
Publication Type: Proceedings
Publication Acceptance Date: 6/5/2007
Publication Date: 9/9/2007
Citation: de Beer, M., Coon, C.N., Rosebrough, R.W., Russell, B.A., Richards, M.P. 2007. The role of feeding regimens in regulating metabolism of broiler breeders: hepatic lipid metabolism, plasma hormones and metabolites. Symposium on Energy and Protein Metabolism and Nutrition. EAPP publication No. 124:369-375.
Interpretive Summary: Excess fat production by the modern broiler chicken presents a two-fold problem. The consumer has health concerns about the link between cardiovascular disease and dietary fat in meat type chickens. The broiler breeder producer is concerned about the relationship between excess body fat and reproductive inefficiencies during period leading up to the egg-laying period. The latter condition was studies in broiler breeder candidates raised to sexual maturity. Candidates were raised under two regimens: 1) feed allowed every day and 2) feed allowed every other day to restrict total feed intake. Restricting feed, followed by access to feed produced a syndrome similar to that seen in younger birds subjected to fasting-refeeding. Furthermore, this management regimen also caused excess liver fat accumulation and a potential for fatty liver hemorrhagic syndrome and death. Enzyme activity of certain rate limiting pathways reflected noted changes in gene expression and show the potentially significant impact of feeding regimens on gene expression in breeder pullets. In addition, these data should allow broiler breeder producers to design management regimens to maximize the health of breeder candidate hens.
Technical Abstract: A flock of 350 Cobb 500 breeder pullets was divided in two at 4 weeks of age and fed either everyday (ED) or skip-a-day (SKIP) from 4 to 16 weeks of age. Total feed intake did not differ between the two groups. At 112 d, 52 randomly selected pullets from the ED fed pullets, and 76 from the SKIP fed pullets were individually caged and fed a meal of 74 g (ED) or 148 g (SKIP) of the same standard pullet grower ration. Four pullets from each group were sacrificed at several intervals after feeding and livers were collected, weighed and snap frozen for determination of lipogenic gene expression. Blood samples were also collected for hormone and metabolite analysis. ANOVA and Tukey’s Studentized range test were performed using JMP IN 5.1 software with significance based on testing at P less than 0.05.