Arnold R. Hippen
Two commercially available, qualitative, on-farm test kits (Midland BioProducts Inc., Boone, lA), utilizing either serum or whole blood to evaluate failure of passive transfer (FPT) of immunoglobulins, were evaluated using 38 Holstein calves. Results from the kits were compared with refractometry determination of serum proteins and radial immunodiffusion determinations specific for IgG (RID; Triple J Farms, Bellingham,WA). Blood samples were collected immediately following birth before first colostrum feeding and at 48 h. At birth, serum protein concentrations averaged 4.52 g/dl and IgG averaged 8.6 mg/dl, respectively, for refractometer and RID. Forty eight hours after feeding colostrum, serum protein concentrations averaged 6.02 g/dl and IgG concentrations were 2129.3 mg/dl. Feeding colostrum increased serum protein and IgG concentrations at 48 h (P < 0.01). Serum protein concentrations determined by refractometry and serum IgG determined by RID were positively and significantly correlated (r^ = 0.78, P < 0.01) and the relationship is characterized as: serum protein, g/dl = 0.0007 mglg5/dl + 4.5726. Adequate immune transfer was assumed when serum IgG concentrations were greater than 1,000 mg/dl or FPT with IgG less than 1,000 mg/dl. Using samples of blood from calves collected prior to feeding colostrum, the accuracy of the on-farm plasma kits for adequate passive transfer was 100% (n = 29). The accuracyof the whole blood kits for assessing adequate passive transfer of IgG on samples from newborn calves was 95.5% with 4.5% false positives(n = 22). On blood samples from calves fed colostrum, the whole blood kits presented4.5% false negative readings and 0% false positives (n = 22). On the colostrum-fed calves, the plasma kit predicted passive transfer with 100% accuracy (n = 30).
"A Comparison of Methods for On-Farm Determination of Failure of Passive Transfer of Immunoglobulin to Dairy Calves,"
The Journal of Undergraduate Research: Vol. 1
, Article 4.
Available at: http://openprairie.sdstate.edu/jur/vol1/iss1/4