母猪妊娠后期热应激对仔猪肌纤维发育的影响.

[Objectives] The paper aimed to investigate the effects of heat stress in late gestation on differentiation, development and apoptosis of piglet skeletal muscle. [Methods] Twelve sows (Dabai × Changbai) with similar due dates were selected, in the late gestation (84 days of gestation), the sows were randomly divided into heat stress group (HS, 28-32 ℃) and control group (CON, 18-22 ℃) . After farrowing, longissimus dorsi (LD) was collected from one weaning piglet per litter. Western blot was used to detect the expression of related proteins in the samples. [Results]Heat stress of sows during late gestation significantly increased the contents of INF-γ and COR in colostrum (P<0.05); heat stress in late gestation of sows significantly decreased MyoD protein expression level of LD (P<0.05), and increased Myogenin protein expression level of LD (P<0.05); and heat stress in late pregnancy of sows, the protein expression level of MyHCⅡb in LD of weaning piglets significantly increased (P<0.05), but MyHCⅡx protein expression level had no significant changes (P>0.05); the glucose metabolism-related protein expression showed that heat stress in late gestation of sows significantly reduced PCK1 and GLUT4 expression levels in LD of weaning piglets (P<0.05); the expression levels of apoptosis-related proteins Bax and Bcl-2 in LD of weaning piglets significantly increased by heat stress during late gestation (P<0.05) . [Conclusions] Heat stress in sows during late gestation could significantly reduce the body weight and LD weight of weaning piglets, it might be related to the decreased expression level of MyoD and glucose metabolism in LD of weaning piglets. [ABSTRACT FROM AUTHOR]