Effect Of Early And Late Feed Restriction On Fatty Acid Metabolism In Broiler Chickens

The present experiment was conducted to investigate the long-term effect of earlypost-hatch feed restriction (food provided every other day during first 2 weeks afterhatching, EFR) and late feed restriction (food provided every other day during 2 weeksbefore slaughtering, LFR) on fatty acid metabolism and fatty acid composition in broilerchickens, and to find the metabolic programming mechanism of early post-hatch feedrestriction on fatty acid metabolism of broiler chickens.1 Effect of feed restriction on plasma and liver fatty acid metabolismbiochemical parameters in broiler chickens.Plasma concentrations of triglyceride(TG), total-cholesterol(TC), low density lipoproteincholesterol(LDLC), high density lipoprotein cholesterol(HDLC), liver concentrations of TG, TC, freefatty acid(FFA) and activation of lipoprotein lipase (LPL) were measured. The body weight wassignificantly lower in EFR group at 14 and 63 days of age, whereas there was no significant change inLFR group. No significant changes were found for any investigated indices at 14 days of ageimmediately after early feed restriction except EFR plasma concentrations of TC and HDLC weresignificant higher than Control, liver concentrations of TG and TC were significant lower than Control.LFR group plasma concentrations of TG, TC, LDLC, HDLC and liver concentrations of TG, TC, FFAwere significant higher than Control. The results indicated that both early and late feed restriction couldchange the fatty acid metabolism in broiler chickens.2 Effect of feed restriction on fatty acid composition of broiler chickens.Breast and leg muscle intramuscular fat content and fatty acid composition weremeasured. Early feed restriction chickens showed significantly lower breast stearic acid anddocosahexenoic acid compared with control group; late feed restriction chickens hadsignificantly lower breast intramuscular fat content, but showed significantly highersaturation/unsaturation fatty acid ratio in leg muscle. The results indicated that both earlyand late feed restriction could reduce the meat quality in market broiler chickens.3 Effect of feed restriction on fatty acid metabolism key enzyme andregulating factors in broiler chickens. mRNA expression of liver acetyl- CoA Carboxylase-α(ACC-α), CamitinePalmitoyltransferaseⅠ(CPT-Ⅰ), Sterol Regulatory Element-Binding Protein-1c(SREBP-1c) and Peroxisome Proliferator-activated receptorsα(PPARα), and activation ofAMP-activated protein kinase, mRNA expression of breast CPT-Ⅰwere measured. Nosignificant changes were found for any investigated indices at 14 days of age immediatelyafter early feed restriction except EFR mRNA expression of breast CPT-Ⅰwas significanthigher than Control, at 63 days of age EFR chickens exhibited significantly lower ACC-αand higher CPT-ⅠmRNA expression compared with the control counterparts; LFRchickens also showed significantly higher ACC-α, SREBP-1c, PPARαmRNA expression,but significantly lower liver and muscle CPT-ⅠmRNA expression compared with thecontrol counterparts. The results showed that early post-hatch feed restriction could exertlong-term effect on fatty acid metabolism in broiler chickens.4 Metabolic programming mechanism of early post-hatch feed restriction onfatty acid metabolism in broiler chickens.Plasma, liver and muscle concentrations of malonilaldehyde (MDA), activities ofsuperoxide dismutase (SOD), glutathione peroxidase (GPX) of 14 and 63 days old broilerchickens, Liver mitochondrion structure and function 14 days old broiler chickens weremeasured. No significant changes were found for any investigated indices at 14 days of ageimmediately after early feed restriction. However, at 63 days of age, EFR chickensexhibited significantly higher serum MDA concentration and GPX activity compared withthe control counterparts, significantly lower liver SOD activity. LFR chickens also showedsignificantly higher serum MDA concentration as well as SOD and GPX activities at 63days of age, but significantly lower liver MDA concentration compared with the controlcounterparts. Different types of muscle seem to respond differently to late feed restrictionin terms of SOD activity. Pectoral muscle showed lower SOD activity while no change wasobserved in gastrocnemius muscle. EFR group of 14 days old broiler chickens Livermitochondrion showed significantly lower SOD activity and fluidity, structure and functionwere damaged. So the changes of Liver mitochondrion structure and function 14 days oldbroiler chickens may be the one of metabolic programming mechanism of early post-hatchfeed restriction on fatty acid metabolism of broiler chickens.