Serum immunoglobulin concentrations after feeding maternal colostrum or maternal colostrum plus colostral supplement to dairy calves.

Maternal colostrum or maternal colostrum plus colostral supplement, composed of a blend of lyophilized colostrum and dried whey, was fed to 32 Holstein calves as soon as possible after birth (mean +/- SEM = 2.0 +/- 0.2 hours) and, again, 12 hours later. Mean immunoglobulin concentration in colostrum was 59.2 mg/ml; mean immunoglobulin fraction in supplement was 11.4%. Serum immunoglobulin concentrations were measured at 0, 12, 24, 48, and 72 hours, and at 28 and 56 days. Hour/treatment interactions were significant for total immunoglobulin, IgG1, and IgM concentrations. Immunoglobulin concentrations were highest at 12 hours (total immunoglobulin, IgG1, IgM) or 24 hours (IgG2) in calves fed colostrum plus supplement, whereas all immunoglobulin concentrations were highest at 24 hours in calves fed maternal colostrum only. Peak mean immunoglobulin concentrations did not differ between treatments. Supplementation of colostrum did not increase peak mean serum immunoglobulin concentration, but did alter the serum concentration-time profile from 12 to 72 hours after birth.