Bovine respiratory disease (BRD) is one of the costliest health issues facing the beef industry today. While a lot of research on BRD has been focused at the feedlot stage, the disease is also the most common cause of death for nursing calves older than three weeks. BRD can impact any producer, including those who retain ownership of their calves to background, feed, or finish cattle.
Research by USDA ARS Meat Animal Research Center that tracked the annual incidence of BRD in pre-weaned calves over a 20-year period found that the annual incidence varied from a low of 3% to a high of 24% with an overall annual average of 11%. On average, the mortality rate of calves suffering from pre-weaning BRD was 13%.
Several large studies have linked BRD to seasonal peaks. Nebraska researchers collected several years of data on 110,000 calves and found two seasonal peaks in the incidence of BRD. One peak occurs from birth through around 20 days of age, and another takes place when calves reach 70 to 100 days of age. Other studies have shown a similar pattern. The most common age group reported as having BRD were calves between one to 4 months of age.
Once calves are affected by BRD, there are both immediate and long-lasting effects on performance. Studies have shown that calves challenged by BRD could weigh up to 36 pounds less at weaning than their healthy herd mates (Wittum and Perino, 1995). Continue reading