Comparing the gastrointestinal barrier function between growth-retarded and normal yaks on the Qinghai-Tibetan Plateau

Jian Ma; Ali Mujtaba Shah; Zhisheng Wang; Rui Hu; Huawei Zou; Xueying Wang; Guang Cao; Quanhui Peng; Bai Xue; Lizhi Wang; Suonan Zhao; Xiangying Kong

doi:10.7717/peerj.9851

Comparing the gastrointestinal barrier function between growth-retarded and normal yaks on the Qinghai-Tibetan Plateau

PeerJ. 2020 Sep 3:8:e9851. doi: 10.7717/peerj.9851. eCollection 2020.

Authors

Affiliations

¹ Low Carbon Breeding Cattle and Safety Production University Key Laboratory of Sichuan Province, Animal Nutrition Institute, Sichuan Agricultural University, Chengdu, China.
² Haibei Demonstration Zone of Plateau Modern Ecological Animal Husbandry Science and Technology, Haibei, China.

Abstract

Background: Yak (Bos grunniens) is an ancient bovine species on the Qinghai-Tibetan Plateau. Due to extremely harsh condition in the plateau, the growth retardation of yaks commonly exist, which can reduce the incomes of herdsman. The gastrointestinal barrier function plays a vital role in the absorption of nutrients and healthy growth. Functional deficiencies of the gastrointestinal barrier may be one of the contributors for yaks with growth retardation.

Methods: To this end, we compared the growth performance and gastrointestinal barrier function of growth-retarded (GRY) and normal yaks (GNY) based on average daily gain (ADG), serum parameters, tissue slice, real-time PCR, and western blotting, with eight yaks in each group.

Results: GRY exhibited lower (P < 0.05) average daily gain as compared to GNY. The diamine oxidase, D-lactic acid, and lipopolysaccharide concentrations in the serum of GRY were significantly higher (P < 0.05) than those of GNY. Compared to GNY, the papillae height in the rumen of GRY exhibited lower (P = 0.004). In jejunum, with the exception of higher villus height, width, and surface area in GNY, numerical difference (P = 0.61) was detected between two groups for crypt depth. Both in rumen and jejunum, the mRNA expression of interleukin-1beta in GRY was markedly higher (P < 0.05) than that in GNY, but an opposite trend was found in interleukin-10 expression. Moreover, GRY showed a higher (P < 0.05) tumor necrosis factor-alpha mRNA expression in the rumen. The claudin-1 (CLDN1), occludin (OCLN), and zonula occludens-1 (ZO1) expressions of GRY in rumen and jejunum were significantly down-regulated (P < 0.05) as compared to GNY. The correlation analysis identified that in rumen and jejunum, there was a positive correlation between interleukin-10 and CLDN1, OCLN, and ZO1 mRNA expressions, but the tumor necrosis factor-alpha was negatively correlated with CLDN1, OCLN, and ZO1. In the rumen, the ADG was positively correlated with papillae surface area, and a same relationship between ADG and CLDN1, OCLN, and ZO1 expressions was found.

Conclusion: The results indicated that the ruminal and jejunal barrier functions of GRY are disrupted as compared to GNY. In addition, our study provides a potential solution for promoting the growth of GRY by enhancing the gastrointestinal barrier function.

Keywords: Growth-retarded yak; Inflammatory cytokine; Jejunal epithelium; Ruminal epithelium; Tight junction protein.

Grants and funding

The present study was supported by the National Natural Science Foundation of China (No. 31972591) and the China Agriculture (Beef Cattle/Yak) Research System (CARS-37). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.