Serum Inflammatory Cytokine Profiles in Cattle with Bovine Respiratory Disease Complex in Katsina State

Bovine respiratory disease complex represents the most economically costly disease syndrome in feedlot cattle globally and is increasingly documented in Nigerian feedlot enterprises. The condition involves complex interactions between viral and bacterial pathogens, immunosuppressive stressors, and host inflammatory responses mediated by cytokines including tumour necrosis factor alpha, interleukin-1 beta, interleukin-6, and interleukin-10. In Katsina State, North West Nigeria, where cattle feedlots supply beef to both northern and southern markets, the inflammatory immunopathology of bovine respiratory disease has not been characterised. This study measured serum cytokine profiles in cattle with mild, moderate, and severe bovine respiratory disease at feedlots in Katsina city and compared them with healthy control animals. Eighty cattle were classified using a validated bovine respiratory disease scoring system, and serum was collected for ELISA-based quantification of TNF-alpha, IL-1 beta, IL-6, IL-8, IL-10, and haptoglobin. TNF-alpha and IL-6 concentrations increased significantly with disease severity, with the highest concentrations recorded in moribund animals. IL-10 showed a paradoxical increase in severely affected animals, suggesting concurrent anti-inflammatory responses or immunosuppression. Haptoglobin, as an acute phase protein, correlated positively with all pro-inflammatory cytokines. Animals treated with flunixin meglumine showed significantly lower IL-6 concentrations at 48 hours compared with untreated animals of equivalent severity, validating the anti-inflammatory mechanism of NSAID therapy. These findings illuminate the immunopathological basis of bovine respiratory disease in Nigerian feedlot cattle and identify cytokines as potential biomarkers for disease monitoring and therapeutic evaluation. Keywords: bovine respiratory disease, cytokines, interleukin, Katsina, inflammation.