Serum neutralizing antibody concentrations against viral bovine respiratory pathogens in nursing beef calves

Nursing calf bovine respiratory disease (BRD) is a problem for some herds, and the timing of maternal antibody decline may be related to risk for calves to develop BRD. Limited information is available on the distribution of serum maternal antibody titers among calves within and between cow-calf herds. Understanding how maternal antibody concentrations vary within and between herds may help us understand what puts nursing (preweaned) calves at risk for BRD. The objective of this study was to test the effect of calf age and farm on the magnitude of serum neutralizing antibody (SNA) titers against viral causes of BRD in nursing calves among herds in a similar geographic location.