Vaccination: Is it Effective in Preventing Respiratory Disease or Influencing Weight Gains in Feedlot Calves?
Respiratory disease, both undifferentiated and etiologically defined, remains a major problem in feedlot cattle. Vaccination has been used in an attempt to reduce the frequency and/or severity of respiratory disease in the first few weeks after the cattle arrive at the feedlot.The efficacy of vaccination has been studied both in controlled laboratory experiments and field trials as well as observational studies. (In this review, efficacy refers to the ability to reduce overall treatment rate and/or increase weight gains.) This review summarizes the data resulting from studies of vaccine efficacy.In general, there is little published data to support the use of vaccines against respiratory disease under feedlot conditions. Treatment rates and weight gains usually did not differ between vaccinated and nonvaccinated groups. The use of live bovine virus diarrhea virus vaccines was associated with a significant subsequent increase in treatment rates. Criteria to be considered in future field trials are described.
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