Studies Of Blood Biochemical Parameters And Key Genes Expression Profile In Indigenous Chickens When Exposure To High Temperature

Chinese indigenous chicken breeds from different latitude show their own adaptationin a certain climatic condition. In the present study, Huainan partridge (H) chicken fromcentral China and southeast Wenchang (W) chicken were used to investigate the patternsof blood biochemical parameters and expression profile of heat-stress related key genes byQRT-PCR between the two breeds. Besides, correlation analysis between tissue expressionprofile and partial blood biochemical indicators was also conducted.1. There were not significant differences in GLU, TG, TC, TP, CK and ALP betweenH and W under heat tolerance. However, there were significantly different in T3, T4, ALB,GLB, A/G and ALT between two local chicken breeds from different latitude (P<0.05).There was significant difference in the level of T3between two chicken breeds during theperiod of0h,12h,24h,72h and R24h (P<0.05). T4reached the maximum of25.60nmol/Lin W at high temperature of24h and was significantly higher than that of Huainanpartridge chicken (P<0.05). The level of ALB in Huainan partridge chicken wassignificantly lower than that of Wenchang chicken during the period of experimentalgroups. GLB also reached the maximum at the high temperature12h between two Chineseindigenous chickens. The level of A/G in Huainan partridge chicken was significantlylower than that of Wenchang chicken during the period of12h,24h,72h and R12h(P<0.05).Besides, the level of ALT in Huainan partridge chicken was significantly higher than thatof Wenchang chicken at R72h (P<0.05).2. According to the analysis of UGP2mRNA expression in pancreas and liverbetween two indigenous chicken breeds, the level of UGP2mRNA expression reached itsmaximum of3.44at high temperature of24h in Huainan partridge chicken, whereas itreached the maximum of3.11at high temperature of72h. There was significantly differentin the level of UGP2mRNA expression in liver between two indigenous breeds (P<0.05).The level of UGP2mRNA expression in Wenchang chicken was significantly higher thanthat of Huainan partridge chicken during the period of high temperature of72h, R12h andR24h (P<0.05).3. By the analysis of HSP60mRNA expression in hypothalamus and heart between twolocal chickens, there was significant difference in HSP60mRNA expression inhypothalamus and heart between two indigenous breeds (P<0.05). In addition, there wassignificant difference in HSP60mRNA expression between two tissues (P<0.05). The levelof HSP60mRNA expression in hypothalamus in Huainan partridge chicken was significantly higher than that of Wenchang chicken during high temperature of12h, R12h,R24h and R72h, which reached the maximum of362.08at high temperature of12h(P<0.05). The level of HSP60mRNA expression in heart of Huainan partridge chickenwas significantly higher than that of Wenchang chicken and reached the maximum of405.03at high temperature of24h, which was significantly higher than that of R24h andR72h (P<0.05).4. According to the analysis of TLR4mRNA expression in thymus and spleen betweentwo indigenous chicken breeds, there was significant difference in TLR4mRNA expressionin two tissues between two indigenous breeds (P<0.05). Besides, there was significantdifference in TLR4mRNA expression between two tissues (P<0.05). The level of TLR4mRNA expression in thymus of Huainan partridge chicken was significantly higher thanthat of Wenchang chicken under high temperature of24h and72h (P<0.05).5. According to the correlation analysis between key genes and partial bloodbiochemical indices, the significant correlation coefficient between the level of TLR4mRNA relative expression in thymus and TP, ALB, GLB, A/G in Huainan partridgechicken was0.561(P<0.01),-0.623(P<0.01),0.636(P<0.01),-0.514(P<0.01), respectively.In liver, the coefficient of correlation between two parts was0.457(P<0.01),-0.397(P<0.05),0.503(P<0.01),-0.462(P<0.01), respectively. However, there was notsignificant correlation between two parts in Wenchang chicken.From the above results, it is suggested that there is difference in heat resistancebetween Huainan partridge chicken and Wenchang chicken when exposure to hightemperature.