Prickly Ash Seeds Improve the Ruminal Epithelial Development and Growth Performance of Hu Sheep by Modulating the Rumen Microbiota and Metabolome

It is known that the addition of feed rich in bioactive components to animal diets will affect rumen fermentation parameters and flora structure. However, research on the regulatory effects of prickly ash seeds (PASs) during rumen development or on the rumen microbiome and its metabolites in sheep is limited. The current study was designed to explore the effects of PASs on sheep rumen development and growth performance using metagenomics and metabolomics. Eighteen 3-month-old Hu lambs were randomly allotted to three different dietary treatment groups: 0% (basal diet, CK), 3% (CK with 3% PAS, low-dose PAS, LPS), and 6% (CK with 6% PAS, high-dose PAS, HPS) PASs. The lambs were slaughtered to evaluate production performance. Our results showed that dietary PAS addition improved the average daily gain and reduced the F/G ratio of the experimental animals. Additionally, the height and width of the rumen papilla in the treatment groups were significantly higher than those in the CK group. The fermentation parameters showed that the levels of acetate and butyrate were significantly higher in the LPS group than in the CK and HPS groups. The propionate levels in the HPS group were significantly higher than those in the CK and LPS groups. Metagenomics analysis revealed that PAS dietary supplementation improved the abundance of Clostridiales and Bacteroidales and reduced the abundance of