Effect of Corn Straw Treated with Lactobacillus plantarum and Cellulase on Ruminal Fermentation and Microbiota of Hu Sheep

Abstract

This study aimed to assess how the bacterial–enzyme co-fermentation of corn straw affects fermentation quality, the digestion rate in Hu sheep, and rumen microorganisms. Orthogonal experiments were utilized to establish the optimal fermentation conditions, which were subsequently applied in bacterial–enzyme fermentation trials involving four groups: group A (control), group B (enzyme added), group C (bacteria added), and group D (bacteria + enzyme). The results show that the optimal fermentation conditions were the addition of 2% corn flour, 2% cottonseed meal, and 60% moisture. In comparison with group A, group D demonstrated the most favorable outcomes, notably reducing the pH and cellulose content while enhancing the lactic acid content. The relative abundances of Pantoea and Weissella reduced, whereas those of Lactiplantibacillus and Limosilactobacillus increased, in the fermented corn straw. In the animal experiments, group D exhibited significantly higher digestibility of NDF and ADF; total VFA, acetic acid, and NH3-N contents; and enzyme activity compared with groups A and B. Additionally, the relative abundances of Prevotella, NK4A214-group, Entodinium, and Polyplastron increased, while those of Dasytricha and Enoploplastron decreased, in group D compared with group A. It can be concluded that Lactobacillus plantarum and cellulase treatments enhance the nutritional value of corn straw by improving ruminal fermentation and regulating the sheep rumen microbiota.