Comparative Analysis of the Effects of Mogroside V, Epigallocatechin Gallate, and Resveratrol on Growth Performance, Blood Parameters, Rumen Microbiota, and Short‐Chain Fatty Acid Metabolism in Heat‐Stressed Hu Sheep

Abstract

Hu sheep are highly prized for their tender meat, but heat stress (HS) caused by the high temperature and humidity in southern China severely impacts their performance. This study compared the alleviating effects of Mogroside V (Mog V), epigallocatechin gallate (EGCG), and resveratrol (RES) on HS in Hu sheep. Forty male Hu sheep were randomly divided into a control group and three treatment groups (n = 10), each with a pen. The sheep were housed under HS for 60 days. Body weight, feed conversion ratio (FCR), respiratory rate (RR), and rectal temperature (RT) were monitored. Blood physiological parameters, HSPs, antioxidant enzymes, and inflammatory factors were measured. 16S rRNA sequencing and targeted metabolomics were used to analyze the correlation between rumen microbiota and short-chain fatty acid (SCFA) metabolites. Results showed that all three extracts significantly increased final weight, total weight gain, and daily weight gain, while reducing FCR, RR, and RT. They also decreased HSP70/90, MDA, and the inflammatory factors TNF-α, IL-1β, and IL-6, and increased antioxidant enzyme activity. Microbiome and metabolome analysis revealed that RES increased Verrucomicrobia and Fibrobacterium, promoting propionic and butyric acid production; Mog V enriched Firmicutes and Clostridium succinate, promoting energy metabolism; and EGCG regulated acetate metabolism through Lactobacilli, inhibiting pathogenic bacteria. In summary, all three plant extracts alleviated the physiological damage caused by HS and improved production performance, with Mog V showing the most significant effect and possessing high potential for application.