Objective-To compare the efficacy of 3 commercially available colostral-supplement products with that of natural bovine colostrum in providing immunoglobulins ?or passive transfer and disease protection. Design-Prospective randomized control trial. Animals-47 neonatal female Holstein calves from unassisted, observed births. Calves were vigorous, stood within 90 minutes of birth, and did not suckle their darns. Procedure-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 calves during the first 30 days of life was compared. Results-Calves fed natural 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. Group-1 calves had significantly (P < 0.05) fewer episodes of disease during the first 30 days of life, compared with carves fed colostral-supplement products. Clinical Implications-Commercially available colostral-supplement products are less efficient at providing immunoglobulin transfer and disease protection to newborn calves, compared with bovine colostrum, even when fed at equal volume and similar immunoglobulin concentration.
