COMPARISON OF PASSIVE IMMUNOGLOBULIN TRANSFER TO DAIRY CALVES FED COLOSTRUM OR COMMERCIALLY AVAILABLE COLOSTRAL-SUPPLEMENT PRODUCTS

Objective-To compare the efficacy of 3 commercially available colostra l-supplement products with that of natural bovine colostrum in providi ng immunoglobulins ?or passive transfer and disease protection. Design -Prospective randomized control trial. Animals-47 neonatal female Hols tein calves from unassisted, observed births. Calves were vigorous, st ood within 90 minutes of birth, and did not suckle their darns. Proced ure-Calves were fed 2 L of colostrum or a colostral-supplement product within 2 hours after birth and again prior to 12 hours of age. Serum IgG concentrations were measured at 24 and 48 hours after parturition, and apparent percentage of absorption for the colostrum and for each product was calculated. Prevalence of disease in all 4 groups of calve s during the first 30 days of life was compared. Results-Calves fed na tural bovine colostrum (group 1) had highest serum IgG concentrations (range, 12.4 to 31.6 mg/ml) at 24 hours after birth, whereas serum IgG concentrations in calves fed colostral products ranged from 1.9 to 8. 6 mg/ml. Values for apparent percentage absorption of colostral IgG in group-1 calves was 3 times that of calves fed colostral products. Gro up-1 calves had significantly (P < 0.05) fewer episodes of disease dur ing the first 30 days of life, compared with carves fed colostral-supp lement products. Clinical Implications-Commercially available colostra l-supplement products are less efficient at providing immunoglobulin t ransfer and disease protection to newborn calves, compared with bovine colostrum, even when fed at equal volume and similar immunoglobulin c oncentration.