The quality of colostrum is a key factor in healthy calf growth, and pasteurized colostrum is effective in reducing pathogenic microorganisms in it. However, there is limited information on the molecular mechanism of the effect of pasteurized colostrum on calf growth and development. The aim of this study was to identify key genes and functional pathways through which pasteurized colostrum affects calf growth and development using RNA sequencing. A total of 630 differentially expressed genes (235 up-regulated and 395 down-regulated) were screened from the pasteurized and unpasteurized groups. PPI detected three key sub-networks involved in mitochondrial pathway, protein synthesis and immune response. All expressed genes were classified into 12 modules by WGCNA, among which brown and green modules were closely related to pasteurization, and key genes in the modules were mainly involved in "mitochondrial envelope", "TCA cycle" and "NF-kappa B signaling pathway". By GSEA, 10 immune and metabolic related gene sets were found to be upregulated in the pasteurization group. Finally, three key genes that undergo alternative splicing were identified, including RIPK1, BOLA-NC1 and TMEM173. In summary, our data provide further evidence that pasteurized colostrum has a positive effect on calf growth and development, providing a scientific basis for healthy calf culture and management.

Alternative Splicing;Pasteurization;Holstein;calves;WGCNA;RNA-Seq