Estrogen Excretion by Cows after Oral Administration of Diethylstilbestrol

Abstract
Estrogen excretion by the cow has been investigated by using the response of the uterus of the immature mouse to estrogenic activity of feces, urine, milk and bile. No detectable estrogen was found in feces and urine from three ovariectomized cows. The combined daily fecal and urinary excretion ranged from 55.2 to 84.1% by ovariectomized cows receiving orally 10 mg. of DES per day. The excretion range was from 42.2 to 76.1% when the daily DES intake level was 100 mg. The average percentage of the estrogen intake recovered in the urine and feces per day was 63%, calculated as DES. Treatment of cow urine with beta-glucuronidase increased the estrogenic activity in some cases. Little, if any, estrogenic activity was found in milk from a cow 3 weeks post-partum. Milk from pregnant cows showed a small amount of activity. A slight increase in the estrogen content of milk was found after DES administration to pregnant cows. The total daily urinary excretion of estrogen by a cow, 7 months pregnant, was 0.62 mg., calculated as DES. Assays indicated a small amount of activity in gall-bladder bile following the daily administration of 1 mg. of DES for 7 days. Copyright © . .