Estrogens in the feces of the new-born calf

Abstract

The estrogenic content of the feces of four male and six female calves, during the first 11 days of life, was measured by using the bioassay technique for uterine weight increase in immature mice. The estrogenic content of the feces of the calves was significantly higher (P < 0,001) until three days of age and higher (P < 0,05) on the fourth day than at subsequent ages. The presence of estrogenic substances in the feces was not detected in three of the ten calves (30%) at the three days of age. This percentage increased to 70% on the fourth day. By the fifth day, estrogenic activity was not detected in the feces of any of the calves examined. These results indicate that estrogens of maternal origin are eliminated within the first days of life. Thus, it does appear reasonable that estrogens are not provided by the colostrum or milk.