Physiological Responses and Gut Microbiota Dynamics in Beef Cattle following Transport Stress Syndrome with Melatonin or Dexmedetomidine Administration
Description
Transport can induce stress in beef cattle, which may affect physiological status and the gut microbiota, ultimately compromising animal welfare and production performance. In the context of transport stress, this study explored the potential influences of melatonin and dexmedetomidine on stress-related responses in Simmental bulls. Cattle received melatonin, dexmedetomidine, or physiological saline before a 6 h transport, and blood and fecal samples were collected before transport and on days 1, 4, and 7 after transport. The results showed the Shannon diversity index decreased significantly in the control group on day 7, whereas microbial diversity remained relatively stable in the melatonin and dexmedetomidine groups, and gut microbial community structure gradually diverged over time. No obvious clinical abnormalities were observed during the study period, and no treatment-related safety risks were identified. Overall, melatonin and dexmedetomidine were associated with changes in selected post-transport physiological parameters and gut microbiota features, supporting further evaluation in larger studies and under different transport conditions to clarify their potential roles in transport-stress management in beef cattle.