Comparative Analysis of Health, Inflammatory Markers, and Rumen Microbiota Between Mildly Lame and Healthy Cows.

Bovine lameness leads to significant economic losses in the dairy industry. This study investigated the relationship between rumen microbiota and lameness in Holstein cows. Rumen fluid and blood samples were collected from 11 cows with mild lameness and 10 healthy cows before morning feeding. Using high-throughput sequencing and ELISA kits, we found that cows with lameness exhibited decreased rumen pH and increased lameness scores compared to healthy cows. Additionally, cows with lameness had higher blood concentrations of LPS, IL-1, IL-8, and TNF-α. Although there were no significant differences in microbial alpha diversity, principal coordinate analysis (PCoA) revealed significant differences in the rumen microbial structure between the two groups. Further analysis showed that the relative abundances of ruminal Clostridium_IV, Streptococcus, Bacillus, Acinetobacter, Desulfobulbus, Methanobrevibacter, and Mogibacterium were significantly higher in the lameness group, whereas Succinivibrio, Lachnobacterium, Elusimicrobium, Succiniclasticum, and Prevotella were significantly more abundant in the rumen of healthy cows. Importantly, the microbial interaction network in the rumen of cows with lameness was more complex, with key bacteria such as Mogibacterium dominating the microbial interaction network. This study highlights the relationship between rumen microbiota and lameness, providing insights into the prevention and treatment of bovine lameness.