Effect of Reserpine and Three Phenothiazine Derivatives on Growing-Fattening Swine

Abstract

A total of 136 Yorkshire, Berkshire and Yorkshire × Berkshire pigs were used in two experiments to study the effect of tranquilizers on rate of gain and efficiency of feed utilization when added to the feed continuously through the growing-fattening period. In Experiment I no significant differences were obtained among lots by the addition of 28.4 or 56.8 mcg. reserpine per lb. of feed in trial 1, although there was a tendency for greater rate of gain among treated pigs during the first 13 days on test. In trial 2 no significant differences were obtained by the addition of 14.2, 28.4, or 56.8 mcg. reserpine per lb. of feed. A slight depression in growth of pigs receiving the highest level was not accompanied by changes in rectal temperature or blood cholesterol level. In Experiment II, a slight, but not statistically significant, increase in average daily gain of pigs receiving 0.5 or 1.0 mg. trifluoperazine per lb. of feed was obtained in trial 1. No response was obtained from 5.0 mg. chlorpromazine per lb. of feed. In trial 2 no significant differences were obtained by the addition of 0.5 or 1.0 mg. trifluoperazine or 0.5 mg. trifluomeprazine per lb. of feed.