Submitted to: International Conference and Exhibition on Veterinary Poultry
Publication Type: Abstract Only
Publication Acceptance Date: October 18, 2007
Publication Date: November 18, 2007
Citation: DeBeer, M., Ekmay, R.D., Rosebrough, R.W., Richards, M.P., McMurtry, J.P., Coon, C.N. 2007. The role of feeding regimens in regulating metabolism of sexualy mature broiler breeders: hepatic lipid metabolism, plasma hormones and metabolites [abstract]. International Conference and Exhibition on Veterinary Poultry.
A trial was conducted to determine the effects of different rearing feed regimens on plasma hormone and metabolite levels and hepatic lipid metabolism on sexually mature broiler breeders. A flock of Cobb 500 birds was divided into two groups at 35 days of age and fed either everyday (ED) or skip-a-day (SKP). At 168 days of age, all birds were switched over to an ED regimen. At 185 days (26 weeks) of age, 28 ED-reared and 28 SKP-reared birds were randomly selected and sacrificed at intervals after feeding. Liver and blood samples were collected and analyzed. Glycogen, Total Liver Fat and Liver Fat % increased upon feeding regardless of treatment. The magnitude of the increase was greater for SKP birds with peaks achieved by hour 12. Similar findings were reported for birds at 16 weeks of age. Relative Liver Weight increased only in SKP birds. The overall mean gene expression of ICDH, AST, and ACC was not significantly different between treatments. Both ME and FAS were higher in SKP birds and peaked at 8 hours; indicative of continued lipogenesis and consistent with liver fat data. Corticosterone and IGF-2 levels were significantly higher (P<0.05) in SKP birds. Elevated corticosterone levels can be attributed to increased hunger and stress. SKP birds were also higher in Leptin, Glucagon, and T3.The increase in leptin is a reversal of what was reported during the rearing phase. In summary, different feeding regimens alter metabolic responses which carry over into sexual maturity and exhibit metabolic memory.