Does feed restriction and re-alimentation differently affect lipid content and metabolism according to muscle type in pigs (Sus scrofa)?
This study aimed to investigate whether feed restriction and re-alimentation differently affect lipid content and activities of lipogenic or catabolic enzymes according to muscle types in pigs. At around 28 kg body mass (BW), sixty pigs (n=30 per group) were allocated to either ad libitum (AL) or restricted/re-feeding (RA) regimens. After feed restriction (80 kg BW), lipid content was reduced (P<0.01) in the oxidative rhomboideus (RH) as in the glycolytic biceps femoris (BF) muscles of RA pigs compared with AL pigs. Lower activities (P<0.05) of the lipogenic enzymes fatty acid synthase (FAS) and malic enzyme (ME) were observed in the RH but not in the BF of RA vs. AL pigs. After re-feeding (110 kg BW), lipid content was restored in the RH, but was still 12% lower (P<0.05) in the BF of RA compared with AL pigs. In the RH, the trend for an enhanced FAS activity and for a smaller weight-related decrease of ME activity in RA pigs than AL pigs during re-feeding, may have contributed to the muscle fat recovery observed in the RA pigs. In the BF, higher oxidative enzyme activities (P<0.10) in RA pigs compared to AL pigs might explain the incomplete lipid recovery observed after re-feeding in the former animals. In conclusion, metabolic activities in response to restriction and re-feeding differed according to muscle metabolic type.
Gondret
Florence
F
INRA, UMR 1079 Systèmes d'Elevage, Nutrition Animale et Humaine (SENAH), Domaine de la Prise, 35590 Saint-Gilles, France. Florence.Gondret@rennes.inra.fr
Lebret
Bénédicte
B
D000818:Animals; D004064:Digestive System / Q000378:metabolism*; D004734:Energy Metabolism; D004798:Enzymes / Q000378:metabolism; D005247:Feeding Behavior / Q000502:physiology*; D050356:Lipid Metabolism; D008055:Lipids / Q000032:analysis*; D050155:Lipogenesis; D009132:Muscles / Q000737:chemistry* / Q000201:enzymology; D013552:Swine
D004798:Enzymes; D008055:Lipids