Up to the present natural and synthetic steroids have only rarely been considered a cause of disturbances of sexual behavior and anomalies of sex organs. The increasing environmental contamination with chemicals showing estrogenic effects underlines the importance of further investigations in that matter. Therefore, the concentrations of estrogens and progesterone in the faeces of cattle were examined over a 13 weeks period. The values obtained are presented as equivalents of the standard substances estrone and 4-pregnene-20 beta-ol-3-one. The samples were stored in a refrigerator or incubator at temperatures of 5 degrees C and 30 degrees C, respectively, and the investigations were carried out by using an enzyme-immunoassay. Estrogen and progesterone concentrations decreased more rapidly when incubation was performed at 30 degrees C as compared to storage at 5 degrees C, and estrogen values declined more slowly than those of progesterone. When keeping the samples at 5 degrees C the estrogen concentrations decreased to below the basal values only beyond the eleventh week of storage. In contrast, comparable concentrations were already obtained during the third week of the experiment if the samples were stored at 30 degrees C. Progesterone levels decreased to below the basal values during the fourth week of storage at 5 degrees C and during the second week at 30 degrees C.
Download full-text PDF |
Source |
---|
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!