Comparison study of protective effects of porcine bile acids and sheep bile acids against heat stress in chickens.

Abstract

Heat stress (HS) is known to exert negative effects on the poultry and breeding industry, resulting in severe economic losses. Bile acids (BAs), an important component of bile, play a crucial role in improving the production performance of livestock and poultry, alleviating stress injury, and ensuring the health of livestock and poultry. At present, porcine BAs are widely used because of their therapeutic effects on HS; however, it remains unclear whether the same effects are exerted by sheep BAs, which are different from porcine BAs and have different compositions. In this study, we compared the anti-HS effects of porcine BAs and sheep BAs in the diet by establishing an HS model of chicks and investigating the chicken performance, HS-related genes' expression, oxidative stress markers, jejunal histoarchitecture, inflammatory cytokines' expression, jejunal SIgA concentration, and cecal bacterial flora. The results showed that the addition of sheep BAs to the diet increased the average daily weight gain and the feed conversion ratio of chicks. Under HS, sheep BAs was more effective than porcine BAs in improving the activities of LDH and ALT in serum and the content / activity of MDA, SOD and GSH in serum and tissue, reducing the mRNA expression of heat shock proteins (HSP60, HSP70, and HSP90) in the liver and jejunum, and improving the histological structure and the expression of tight junction proteins (Occludin and ZO-1), and enriching intestinal bacterial flora. However, porcine BAs was significantly lower than sheep BAs in reducing the mRNA expression of inflammatory factors (IL-6, IL-1 β and TNF- α). The effect of sheep BAs was more significant in alleviating HS injury in chicks than porcine BAs, suggesting that sheep BAs have great potential as new feed nutrition and health additive to improve poultry production performance and prevent HS. This article is protected by copyright. All rights reserved.