Abstract:The aim of the present study was to assess the effects of heat stress and recovery on biochemical indices and HSP70 mRNA expression in gibel carp (Carassius auratus gibelio). The fishes were selected as experimental animals with an average weight of (72.8±10.1) g under laboratory conditions. Samples used to determine lactic acid (LD) content, glucose (Glu) content, glycogen (Gly) content, hexokinase (HK) activity, pyruvate kinase (PK) activity, and HSP70 mRNA expression were obtained before heat stress (25℃, the control group), 0, 2, 6, and 10 h after stress (32℃), and heat stress recovery (25℃, HSR), respectively. The results revealed no significant difference in LD content compared with that in the control group (P>0.05). Glu content was significantly increased at 0, 2, and 6 h (P<0.01). Gly was significantly increased at 0 h (P<0.01). HK activity was significantly increased at 2 h (P<0.01). PK activity significantly increased at 6 h (P<0.01). Meanwhile, the highest HSP70 mRNA expression was observed at 2 h under heat stress (P<0.01). Following HSR (25℃, 6 h), the HSP70 mRNA expression level recovered to the pre-stress levels (P>0.05). The results provide basic data for research on the mechanism of high temperature adaption in gibel carp, as well as a scientific basis for acute temperature change in aquaculture and breeding.
