INFLAMMATORY RESPONSE TO CLOSTRIDIAL VACCINES IN FEEDLOT CATTLE

In 24 individually housed feedlot steers that weighed 275 hg, clostrid ial vaccines were compared for size of injection site reactions, syste mic inflammatory response caused by vaccination, and impact on feed co nsumption. Vaccines were a bacterin/toxoid containing antigens from mu ltiple clostridial species (7-way), and a Clostridium perfringens type C and D toroid; sterile physiologic saline solution was used as the c ontrol. Injection site reactions were observed in all vaccinated cattl e. Differences in size of lesions were found, with cattle given the 7- way vaccine (7-way group) having the largest lesions. The inflammatory -response to vaccination, measured by serum concentration of the acute -phase protein haptoglobin, was significantly (P < 0.05) increased in both vaccinated groups over that of controls. However, the 7-way group had higher postinjection values than did the group given type C and D toroid. The 7-way group had a significant (P < 0.05) 20% decrease in feed consumption in response to the second injection of vaccine. These findings are indicative of potential negative effects of multiple clo stridial vaccinations.