Effects of selenium (Se) deficiency and supplementation on production of colostral immunoglobulins by beef cows and transfer of antigen-specific and nonspecific immunoglobulins to their calves were examined. Eighty beef cows, with marginal to deficient Se status (blood Se concentration, 50 micrograms/L), were allotted by breed and age to 1 of 4 Se treatment groups (n = 20/group): no supplemental Se; parenteral administration of 0.1 mg of Se and 1 mg of vitamin E/kg of body weight; ad libitum consumption of 120 mg of Se/kg of salt-mineral mix (SMM); and parenteral administration of 0.1 mg of Se and 1 mg of vitamin E/kg plus ad libitum consumption of 120 mg of Se/kg of SMM. All cows were inoculated IM with lysozyme. Cows consumed Se-deficient pastures or hay (21 to 62 micrograms/kg) during the study that began at mid-gestation and ended at postpartum hour 24. Although the concentration of specific lysozyme antibodies was not affected, cows given 120 mg of Se/kg of SMM (treatments 3 and 4) had higher colostral IgG concentration (P < 0.002) than did Se-deficient cows (treatments 1 and 2). Calves from cows in treatments 3 and 4 had higher postsuckle serum concentrations of IgG (P < 0.01) than did calves from cows in treatments 1 and 2. Colostral IgM and calf serum IgM concentrations did not differ among treatments.

Selenium concentration was measured in paired maternal blood samples and fetal liver specimens collected at a San Joaquin County, Calif, slaughterhouse (beef = 19, dairy = 54) and from bovine aborted fetuses submitted to the California Veterinary Diagnostic Laboratory System (CVDLS; beef = 20, dairy = 20). Of the slaughterhouse samples and specimens, dairy maternal blood selenium concentration was significantly (P < 0.001) higher (mean +/- SD; 0.22 +/- 0.056 micrograms/ml) than that for beef breeds (0.137 +/- 0.082 micrograms/ml). The CVDLS mean maternal blood selenium concentration for the dairy-breed samples (0.192 +/- 0.028 micrograms/ml) was similar to that for the slaughterhouse dairy-breed samples, but was greater than that for the slaughterhouse beef-breed samples. Slaughterhouse mean fetal liver selenium content also was higher (P < 0.001) for the dairy breeds (0.777 +/- 0.408 micrograms/g), compared with the beef breeds (0.443 +/- 0.038 micrograms/g). Mean fetal liver selenium content for slaughterhouse specimens was higher (P < 0.002) than that for the CVDLS specimens (beef, 0.244 +/- 0.149 micrograms/g; dairy, 0.390 +/- 0.165 micrograms/g). At the CVDLS, dairy fetal liver content was greater (P < 0.001) than that for beef breeds. Mean ratio of fetal liver selenium content to maternal blood selenium concentration was 3.53 +/- 1.89 for dairy breeds at the slaughterhouse (liver-to-blood correlation [r] = 0.38), and was 2.11 +/- 1.00 for dairy breeds at the CVDLS (r = 0.31) and 3.43 +/- 1.50 for beef breeds (r = 0.58). Both slaughterhouse breed ratios were significantly (P < 0.002) greater than the CVDLS dairy-breed ratio. On the basis of these results, breed and source location should be taken into account when interpreting selenium values. Fetal liver selenium content should only be used as a screening test and combined with whole blood selenium concentration from clinically normal herdmates to evaluate herd selenium status.