Early Solid Diet Supplementation Influences the Proteomics of Rumen Epithelium in Goat Kids

Yimin Zhuang; Xiaokang Lv; Kai Cui; Jianmin Chai; Naifeng Zhang

doi:10.3390/biology12050684

Early Solid Diet Supplementation Influences the Proteomics of Rumen Epithelium in Goat Kids

Biology (Basel). 2023 May 6;12(5):684. doi: 10.3390/biology12050684.

Authors

Yimin Zhuang¹, Xiaokang Lv¹, Kai Cui¹, Jianmin Chai^{2

3}, Naifeng Zhang¹

Affiliations

¹ Key Laboratory of Feed Biotechnology of the Ministry of Agriculture and Rural Affairs, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
² Guangdong Provincial Key Laboratory of Animal Molecular Design and Precise Breeding, College of Life Science and Engineering, Foshan University, Foshan 528225, China.
³ Division of Agriculture, Department of Animal Science, University of Arkansas, Fayetteville, AR 72701, USA.

Abstract

It is well known that solid diet supplementation in early life can significantly promote rumen development and metabolic function in young ruminants. However, the changes in the expressed proteome and related metabolism in rumen epithelium in response to a supplemented solid diet remain unclear. In this study, rumen epithelial tissue from goats in three diet regimes including milk replacer only (MRO), milk replacer supplemented concentrate (MRC), and milk replacer supplemented concentrate plus alfalfa pellets (MCA) were collected for measurement of the expression of epithelial proteins using proteomic technology (six per group). The results showed that solid diet significantly improved the growth performance of goats, enhanced the ability of rumen fermentation, and promoted the development of epithelial papilla (p < 0.05). Proteome analysis revealed the distinct difference in the expressed protein in the MRC and MCA group compared with the MRO group (42 upregulated proteins and 79 downregulated proteins in MRC; 38 upregulated proteins and 73 downregulated proteins in MCA). Functional analysis showed that solid diet supplementation activated a variety of molecular functions in the epithelium, including protein binding, ATP binding, structural constituent of muscle, etc., in the MRC and MCA groups. Meanwhile, the expression of proteins related to fatty acid metabolism, the PPAR signaling pathway, valine, leucine, and isoleucine degradation, and butanoate metabolism were upregulated, being stimulated by solid feed. In contrast, the proteins associated with carbohydrate digestion and absorption and glycosaminoglycan degradation were downregulated. In addition, the protein expression of enzymes involved in ketone body synthesis in the rumen was generally activated, which was caused by solid feed. In summary, solid feed promoted the development of rumen epithelium by changing the expression of proteins related to fatty acid metabolism, energy synthesis, and signal transduction. The ketone body synthesis pathway might be the most important activated pathway, and provides energy for rumen development.

Keywords: goat; protein expression; proteome; rumen epithelium; solid feed.

Grants and funding

This research was funded by the National Natural Science Foundation of China, grant number 31872385, the National Key R&D Program of China, grant number 2018YFD0501902 and Earmarked Fund for China Agriculture Research System, grant number CARS-39.