Prediction of serum IgG concentration by indirect techniques with adjustment for age and clinical and laboratory covariates in critically ill newborn calves.

The objective of this study was to develop prediction models for the serum IgG concentration in critically ill calves based on indirect assays and to assess if the predictive ability of the models could be improved by inclusion of age, clinical covariates, and/or laboratory covariates. Seventy-eight critically ill calves between 1 and 13 days old were selected from 1 farm. Statistical models to predict IgG concentration from the results of the radial immunodiffusion test, the gold standard, were built as a function of indirect assays of serum and plasma protein concentrations, zinc sulfate (ZnSO4) turbidity and transmittance, and serum γ-glutamyl transferase (GGT) activity.

Prevalence of Salmonella spp in selected birds captured on California dairies.

Objective: To determine the prevalence of Salmonella spp in wild birds commonly found on California dairies.

Design: Prospective study.

Animals: 7 selected species of birds were captured on 9 dairies in Kings and Tulare counties, California.

Influence of arrival weight, season and calf supplier on survival in Holstein beef calves on a calf ranch in California, USA.

On a yearly basis, large calf ranches rear thousands of neonatal cattle for replacement heifers, veal or dairy beef. Dairy beef ranches obtain bull-calves from multiple sources and with questionable colostrum intake histories. Such ranches accumulate large amounts of data that could be used to help them with calf purchasing and on-farm management practices to avoid losses.