High maternal body condition score in beef cattle: gut microbiota dysbiosis, immune dysregulation and offspring health implications.

Introduction: This study investigates the correlation between intestinal flora and body condition score (BCS) in beef cattle, focusing on the impact of maternal body condition on gut microbiota and immune function in both cows and their offspring. Material and Methods: Faecal and blood samples were collected at various stages before and after parturition from Hereford beef cattle categorised into normal, higher and high BCS groups. Microbial DNA was extracted and analysed using 16S rRNA gene sequencing to assess microbial diversity and community structure. Results: The research indicated that while maternal BCS had minimal impact on the gut microbiota of cows before and after parturition, significant differences were observed in the microbial composition of calf gut microbiota, particularly those of calves born to cows with higher BCS. Calves from high-BCS cows exhibited increased levels of Proteobacteria, a potential marker for dysbiosis. Immune function analysis revealed higher levels of interleukin 6 and tumour necrosis factor α in both cows and calves from higher-BCS groups, suggesting a link between maternal obesity and offspring health risks. Conclusion: The findings point to the importance of managing body condition in pregnant cows to optimise calf health and reduce disease risks and to the linked role of gut microbiota.