Preliminary Results from a Field Study to Investigate the Relationship between Colostrum Quality and Management and Serum Immunoglobulin Concentrations in Dairy Calves

Abstract

Results of two large national studies indicate that the national preweaning mortality rate in dairy heifers has improved very little over the past ten years (10.8% in National Animal health Monitoring Systems (NAHMS), 1993, 8. 7% in NAHMS, 2002). Failure to reduce mortality in preweaned dairy heifers is partially attributable to poor colostrum management practices. In 1993 (NAHMS), 41 % of 2177 calves sampled between 24 and 48 hrs of age suffered from failure of passive transfer (FPT), or low serum immunoglobulin G (IgG) concentrations. Numerous studies have demonstrated that failure of passive transfer (FPT; calf serum IgG concentration< 10 mg/ml) is associated with a significant increase in risk for morbidity and mortality in the period between birth and weaning (Fowler, 1999; Wells et al, 1996). Conventional factors considered to be important in an effective colostrum management program have included quantity of colostrum fed, quality of colostrum fed (IgG concentration) and quickness (or age at first feeding). Offering a second feeding of colostrum is also frequently recommended. Recently, calf management experts have also begun to evaluate colostrum cleanliness (total bacteria count or total coliform count) as another potentially important factor. Limited studies have suggested that bacteria counts in colostrum not only serve as a pathogen source, but may also reduce efficiency oflgG absorption in the gut. The objective of the current study was to evaluate the relationship between serum IgG concentrations in dairy calves and the aforementioned colostrum management factors (colostrum quantity, quality, quickness, cleanliness).