BRD control: tying it all together to deliver value to the industry

Pasteur described an organism causing fowl cholera in 1880. In 134 years we have progressed from crude vaccines for Pasteurella, to some refined vaccines, to a name change (Mannheimia), to autogenous vaccines (back to crude). In the last 25-30 years, we have attempted to mitigate the problem of bovine respiratory disease with antimicrobials and subsequently have a high incidence of multi-drug resistance. All of these attempts have resulted in little if any improvement in morbidity/mortality. Is it time to focus on the animal's response or lack of response to infectious pressure? Instead of focusing on the 10-50% morbid cattle should we focus on the 50-90% that are not compromised and determine why they stay healthy under the same environmental conditions?