基于蛋白质组学技术分析初乳和常乳摄入对初生犊牛肝脏蛋白表达的影响

【目的】试验旨在对犊牛肝脏蛋白进行蛋白质组学分析，筛选与初乳、常乳摄入相关的蛋白。【方法】以经产荷斯坦母牛分娩的9头公犊牛为研究对象，随机分为初乳组（CI）、常乳组（M）和对照组（CT），每组3头。初乳组和常乳组犊牛分别饲喂初乳和常乳，于出生后24 h屠宰；对照组未饲喂初乳或常乳，于出生后2 h屠宰。采用Label-free蛋白组学技术对3组犊牛肝脏的蛋白表达谱进行分析，以Q<0.05为阈值筛选各组间的差异表达蛋白，并进行GO功能和KEGG通路富集分析。【结果】在犊牛肝脏中共鉴定到3 901个蛋白，其中在初乳组、常乳组和对照组中分别鉴定到3 521、3 646和3 548个蛋白，有3 202个蛋白在3组中共表达。对差异表达蛋白进行分析显示，初乳组和常乳组犊牛肝脏中共筛选出287个差异表达蛋白，主要参与细胞代谢、应激反应、生长发育和氧化还原等生物过程，显著富集通路为内吞作用、氨基酸代谢和氧化磷酸化；初乳组和对照组犊牛肝脏中共筛选出154个差异表达蛋白，主要参与细胞代谢、单组织过程和肌酸合成等生物过程，显著富集通路为氨基酸代谢、黏着斑和内吞作用等。【结论】饲喂初乳的犊牛肝脏中差异表达蛋白主要参与分解代谢、氧化还原等生物过程，为犊牛摄入初乳后肝脏的蛋白响应机制提供了新的见解。

Effect of Colostrum and Milk Feeding on Hepatic Proteins of Calves Based on Proteomics Analysis

【Objective】 This study was aimed to analyze the proteomics of hepatic proteins in calves and screen the differential proteins related to colostrum and milk feeding.【Method】 Nine bull calves delivered by multiparity Holstein cows were randomly divided into 3 groups in this study, including 3 colostrum-fed calves slaughtered at 24 h postpartum (CI group), 3 milk-fed calves slaughtered at 24 h postpartum (M group) and 3 calves not fed any milk or colostrum slaughtered 2 h after birth (CT group).The expression of hepatic proteins in calves in 3 groups were detected using a Label-free approach, the differentially expressed proteins (DEPs) were screened with Q<0.05 as the threshold, and analyzed by GO function and KEGG pathway enrichment analysis.【Result】 The results showed that 3 901 proteins were identified, 3 521, 3 646 and 3 548 proteins were obtained from CI, M and CT groups, respectively.Of these proteins, 3 202 proteins collectively expressed in CI, M and CT groups.Moreover, 287 DEPs in liver of calves have been found to be differentially expressed between CI and M groups, and they were related to cellular metabolism, response to stress, growth and development and oxidation-reduction process, the most significantly enriched pathways were endocytosis, amino acid metabolism and oxidative phosphorylation;And 154 DEPs in liver of calves have been found to be differentially expressed between CI and M groups, which were involved in cellular metabolism, single-organism process and creatine biosynthetic process, the most enriched pathways were amino acid metabolic process, focal adhesion and endocytosis.【Conclusion】 The results revealed that the DEPs in liver of calves fed with colostrum were mainly involved in catabolism and oxidation-reduction process, which provided a new understanding of protein response mechanism in liver of calves after colostrum feeding.