Bovine Respiratory Disease – an Overview of a Continuing Challenge

Bovine respiratory disease complex, remains an important economic disease affecting food animals in North America and worldwide, despite improvements in production management, approval of new medications and continuing research in this area. Production losses due to pneumonia remain nearly constant, adding millions of dollars in industry costs annually. Bovine respiratory disease complex results from the temporal coincidence of variety of events including: stress, viral and bacterial infection and management decisions that have varying impact upon animals raised under widely different conditions. The host’s response to these events varies and dictates the clinical and pathologic responses of these animals. With 9 10 million head of cattle on feed at any one time, managing animals under intensive conditions requires skill and effort. The 1999 NAHMS feedlot survey (National Animal Health Monitoring System), BRDC comprised 17.5% of all production diseases in feedlots. If this percentage is relevant today (and it is likely close to this), this means ~ 1.7 million head required treatment. If the average cost of one treatment per head was $8 ($6.64 – 11.92; NAHMS, 1999), this means that one treatment added 11 20.6 million dollars to production costs. This amount does not include vitamin injections, vaccines, anthelmintics, labor, etc. Furthermore, in those instances where animals require multiple treatments, or are metaphylactically treated, the total cost increases significantly (for 6 or more treatments, cost was $16 in 1999). Respiratory disease remains second to diarrhea as the cause of morbidity and mortality in dairy calves in the USA. It is also a significant cause of morbidity and mortality in dairy animals.