Serological studies on leptospiral antibodies in dairy milkers in three regions of the South Island of New Zealand.

The antibody levels of leptospiral antigens among dairy herds were determined and correlated with those of the milkers in three areas of the South Island of New Zealand. The milkers filled out an extensive questionnaire giving age and sex of the milker, as well as details of the herd milked and his/her association with it. The serological results are compared with these data and the value of such seroepidemiological studies examined from the point of view of the advantages of vaccinating cattle to protecting the milker from leptospirosis. Antibodies to L. interrogans serovar hardjo were the ones most frequently encountered among the milkers; however, antibodies to other serovars were also noted. Some animals in most herds had antibodies to serovar hardjo. These studies suggest that vaccinating cattle with serovar hardjo would not necessarily reduce the human incidence of leptospirosis in this population.

Factors influencing the lipogenic rate in swine adipose tissue.

Measurements of the lipogenic rate in adipose tissue samples obtained sequentially by biopsy from the same pig may be useful for many nutritional experiments. The average lipogenic rate over a short period (several days to 2 weeks) appears to be relatively stable if the pigs weigh about 20 kg initially and if approximately 10 animals are allotted to each experimental group. The lipogenic rate is readily influenced by the feeding regimen (amount and timing). It is easily lowered by less than ad libitum dietary intakes and is influenced especially by the intake pattern for several days preceding the rate determination. In two different experiments, the lipogenic rate obtained at either 20 or 50 kg body weight was not effective as a predictor of backfat thickness or loineye area measured 13 or 6 weeks later, respectively.