Ancillery therapy use and trace mineral supplementation in beef cattle: Impacts on clinical health, immune response variables, animal performance, and carcass traits

Calves treated for bovine respiratory disease (BRD) were randomly assigned to 1 of 4 experimental ancillary therapy (ANC) groups: flunixin meglumine (NSAID), viral vaccination (VACC), vitamin C (VITC), or no ANC (NOAC). When contrasted with the average of the 3 ANCs calves receiving NOAC tended to have heavier BW on d 56, greater ADG and DMI from first BRD treatment through d 28, greater DMI from d 28 through d 56, and had greater DMI from first BRD treatment through d 56 with mortalities and removals excluded (P = 0.06, P = 0.10, P = 0.08, P = 0.06, and P = 0.05 respectively). Morbidity and mortality attributed to BRD were 66.5% and 13.2% respectively. Calves were then grouped by ANC treatment and the number of times treated for BRD (BRDX) and allocated to finishing pens. The BRDX experimental groups included: never treated for BRD (0X), treated 1 time (1X), 2 times (2X), or 3 or 4 times (3/4X). No ANC group differences existed for any of variables analyzed (P ≥ 0.26). With increasing BRDX, days on feed and lung consolidation scores increased linearly (P ≤ 0.01), while hot carcass weight, dressing percentage, rib eye area, and the percentage of USDA Prime and Choice carcasses decreased linearly (P ≤ 0.03). The effects of copper (Cu), manganese (Mn), and zinc (Zn) supplementation on the clinical signs, immune response variables, and mineral status of calves following a bovine viral diarrhea virus (BVDV) and Mannheimia haemolytica (MH) immune challenge were evaluated. Steers were randomly assigned to either mineral supplemented (MIN) or control (CON) experimental treatments. There was a significant (P < 0.0001) time by treatment interaction observed for liver Cu levels. Time significantly impacted the concentrations of Cu, Mn, Fe, and Zn within the liver, Cu, Mn, and Zn within the muscle, and Cu, Fe, and Zn within the serum (P ≤ 0.05). Calves receiving MIN had greater liver Cu (P = 0.0001) and Mn (P = 0.01) concentrations compared to CON calves. In contrast, serum Cu and Fe concentrations were increased (P ≤ 0.05) in CON calves compared to MIN calves.