Expression Of Stress-related Proteins In Beef Cattle Transport And Screening And Validation Of MiRNAs

In the process of beef cattle breeding,the stress response induced by off-site transportation can cause the destruction of the homeostasis of the transported beef cattle,which induces the occurrence of various diseases and seriously affects the healthy development of the beef cattle breeding industry.In the process of transport stress,mi RNAs is presumed to be an emerging diagnostic marker for stress candidates due to its own biological characteristics.Therefore,15 beef cattle were selected and randomly grouped,and then road transported for 0 h,3 h,and 6 h at a speed of 80 km/h to construct a transport-stressed beef cattle model.After that,blood,liver,and spleen samples were collected to assess the transport stress status of the beef cattle,and the transport stress mi RNAs candidate diagnostic markers in the beef cattle liver were screened.The results of ELISA showed that the concentrations of cytokines TNF-?,IL-1,IL-6,IL-10,stress hormone CORT and stress-related proteins Hp?SAA?CRP and HSP70 in serum were significantly increased(P<0.05)after 6 h of transport,the concentrations of SAA,Hp and HSP70 in liver and spleen were significantly increased(P<0.05)as well.The results of q RT-PCR showed that,after 6 h of transport,the expression level of SAA m RNA in liver was significantly increased(P<0.05),that of HSP70 m RNA and CRP m RNA in liver were very significantly increased(P<0.01),and that of SAA m RNA,HSP70 m RNA and CRP m RNA were significantly increased(P<0.05).However,there was no significant change in serum TNF-?,IL-1,IL-6,IL-8,HSP70 and CRP after 3 h of transport.According to the comprehensive assessment,transporting at a speed of 80km/h for 6 hours can promote the beef cattle to be in a state of transport stress.Therefore,the above treatment can be used to construct a beef cattle transport stress model.High-throughput sequencing showed that in the group transported for 6 h,a total of 2029 mi RNAs were up-regulated and 1590 mi RNAs were down-regulated in beef cattle liver tissue.The intersection of the RNAhybrid and mi Randa prediction software was the predicted number of 21946 target genes corresponding to 3619 differentially expressed mi RNAs.The results of GO enrichment showed that the target genes of differentially expressed mi RNAs were involved in important biological processes such as cellular processes and metabolic processes.KEGG pathway enrichment analysis showed that the target genes of differentially expressed mi RNAs were mainly involved in MAPK signaling,thyroid hormone signaling,focal adhesions,c AMP signal transduction and other pathways.It was predicted that the MAPK signal transduction pathway(ko04010)and the focal adhesion pathway(ko04510)were important pathways for target gene involvement.Using q PCR technology for mi R-31,mi R-122,mi R-30 a,mi R-125 b,mi R-152,mi R-186,mi R-199 a,mi R-455,novel-1624,novel-2108,novel-205,novel-817 expression change detection,the results were consistent with high throughput sequencing results.In summary,transporting at a speed of 80km/h and for 6 hours can promote beef cattle in a state of transport stress.Since mi R-186 is involved in important biological processes such as metabolic processes and responses to stimuli,considered it as a candidate diagnostic marker for stress.