| In southern China, High temperature have a long time in summer. Heat stress has been troubled by one of the main dairy production. When the dairy heat stress occurs, the production performance of dairy cows, milk quality decline, immune system disorders, to make it more vulnerable to the invasion of microorganisms and disease and led to a decline in conception rate, cows abortion rate increased to farm has brought considerable economic losses. Therefore, to determine the molecular regulation of heat stress and its possible mechanism of action network, for the development of related genes and their molecular markers, heat-resistant high quality dairy cattle breeding and provide a theoretical basis and technical support.In this experiment,60Chinese Holstein from Zhe jiang Jinhuan Yikang Dairy Production were chosen and divided into4groups, middle lactating period and middle lactating period after exposed to heat sress, late lactating period and late lactating period after exposed to heat sress.Fresh blood genome expression profiling of different groups Chinese Holstein cows was analyzed by Affymetrix Microarray. the MAPKs pathway was chosen as the study target for further analysis from the results of KEGG pathway of2times up or down differential expression genes. The2times up or down differential expression genes in MAPKs pathway were confirmed and candidate genes related heat stress were initially identified. At the same time, The blood indexes, the rectal temperature and the biochemical indexes in peripheral blood at different dairy mean temperatures(37℃,26℃,15℃) were analyzed by different ways(57Chinese Holstein). In addition, the relationship between c-Jun、c-Fos and the rectal temperature, the blood indexes, the biochemical indexes, milk production traits were analyzed by SPSS. We preliminary analy of the c-Jun, c-Fos gene for Chinese Holstein,which have occur heat stress, the feasibility of marker-assisted breeding.Results suggested: 1. The results of the Chinese Holstein cows Affymetrix Microarray showed:Gene quantity and rate of the different periods were middle lactating period15007/62.20%in non heat stress, middle lactating period14308/59.30in heat stress, late lactating period15241/63.20%in non heat stress, late lactating period14734/61.10%in heat stress which there were162-Fold-up-change genes and262-Fold-down-change genes.2. The MAPKs pathway was chosen as the study target for further analysis from the results of KEGG pathway of2times up or down differential expression genes. There are82-Fold-up-change or2-Fold-down-change differential expression genes including p53、 c-Jun、 c-Fos、 TGFBR2、 PRKACA、 PRKACB、ILIB and GADD45A. Differential expression genes involved protein binding, receptor activity, transcription factor activity, serine/threonine protein kinase activity, protein kinase activity and other molecular features.3. The part of the blood indexes at different dairy mean temperatures(37℃,26℃,15℃) were analyzed by automatic analyzer of blood.The blood indexes included as follows: RBC、 HGB、 HCT、 MCV、MCH、 MCHC、RDW-CV、 PLT、PCT、MPV and PDW at15℃than at37℃and26℃. HCT changes significantly at26℃than at37℃(P<0.01). MCH changes significantly at26℃than at37℃(P<0.05). Except above-mentioned the blood indexes, the others don’t change significantly(P>0.05).4. Rectal temperature of Chinese Holstein increased gradually with the environmental temperature rose. In heat stress (37℃) and the critical period of heat stress (26℃), rectal temperature of Chinese Holstein was significantly higher than non-heat stress stress (15℃)(P<0.01), heat stress (37℃) compared with a critical period of heat stress (26℃) has increased, but no significant difference between the two temperatures (P>0.05).5. GSH-PX and T-AOC of blood serum levels of Chinese Holstein increased with the environmental temperature are significantly reduced. Various time periods in which GSH-PX levels were highly significant differences exist (P<0.01); heat stress (37℃) and the critical period of heat stress (26℃). T-AOC of blood Serum of Chinese Holstein was significantly lower than non-heat stress (15℃)(P<0.01), heat stress (37℃) T-AOC was significantly lower than the critical period of heat stress (26℃)(P<0.05).6. Genomic DNA of Chinese Holstein used as template, screening of MAPKs signaling pathways with the gene chip detected the differential gene SNPs. The results showed:c-Jun and c-Fos gene were detected SNPs (0.25<PIC<0.5), and analysed association with some blood, rectal temperature and serum biochemical parameters and milk quality traits by Generalized Linear Models.The association analysis of SNP c-Jun P1with some blood indexes showed that there were no significant effect (P>0.05). The association analysis of SNP c-Fos p5with some blood indexes showed that it was only found for RBC, AA was significantly lower than GG (P<0.05),AA>AG>GG.The association analysis of SNP c-Jun p1with the rectal temperature and serum biochemical analysis showed:it was found only SNP c-Jun G-was significantly higher than the——(P<0.05) about T-AOC in the heat stress (37℃), G—> GG>——SNP c-Fos p5associated with rectal temperature and serum biochemical analysis showed that it was found only SNPc-Fosp5AA was significantly higher than the GG about GSH-PX(P<0.05) in the heat stress (37℃).The association analysis of SNP c-jun p1with milk quality traits showed:GG was significantly higher than G—about milk fat percentage (P<0.05).305days milk yield,305days the amount of milk fat,305days milk protein, milk protein percentage and somatic cell count had no significant effect (P>0.05). The association analysis of SNP c-FosP5with milk quality traits showed:AA was significantly higher than the AG about milk fat percentage (P<0.01).305days milk yield,305days the amount of milk fat,305days milk protein, milk protein percentage and somatic cell count had no significant effect (P>0.05). |
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