Estrogenic Activity of the Meat of Cattle, Sheep and Poultry Following Treatment with Synthetic Estrogens and Progesterone

Abstract

Residual estrogens have been demonstrated in the meat of steers, wethers and chickens treated with synthetic estrogens. The muscle and liver of steers has been shown to contain residual estrogen but in the case of sheep only muscle showed detectable estrogenic activity. There was no demonstrable effect of site of hormone implantation on the amount of hormone retained in the edible tissue. The species differences noted in the amount of residual hormone present are probably a function of time lapse after treatment of the animals with the estrogens. In poultry, the amount of hormone present was reduced quite markedly with time after hormone treatment. In sheep this loss of activity with time was slight. Generally speaking, the greater the amount of hormone used in treating the animals, the greater the amount retained. There was no consistent evidence to indicate that the type of hormone used affected residual amounts in muscle tissue. The only effect of cooking on residual estrogen was a possible loss of amount of activity in the rendered fat or tissue juices but heat (120 to 150° C. for two hours) per se had no effect on the hormone. In all probability, the amount of hormone present in beef muscle and liver does not exceed 0.01 ug. per gram of dried tissue and 0.1 ug. per gram of dried tissue in the case of sheep muscle and chicken meat.