Association Between Serum Mineral and Vitamin A and E Concentration and Respiratory Disease in Beef Calves Entering Backgrounding Lots

The objectives of this study were 1) to measure morbidity and mortality rates attributable to respiratory disease in beef calves originating from southwestern Utah, 2) to evaluate herd of origin vitamin/mineral serum concentration at backgrounding lot entry, and 3) to evaluate a potential association between serum concentrations of 29 minerals and vitamins A and E at backgrounding lot entry with respiratory disease in recently weaned beef calves. This was a prospective longitudinal study with matched case-control and cross-sectional studies nested within the main study design. Pen-specific morbidity rates attributable to respiratory disease ranged from 1.2% to 81.8%. Serum concentrations of vitamins A and E in calves sampled (n=224) from eight southern Utah ranches were commonly less than published low-normal values. In these data, there was no detectable association between serum vitamin A and E or mineral imbalances and respiratory disease. Herds that experience a high rate of bovine respiratory disease (BRD) should be evaluated for mineral and vitamin deficiencies and supplemented as needed. If not deficient, it should not be expected that supplementation would reduce the rate of BRD in the face of mismanagement.