[Use of diazepam for medication of feed for pigs]

Diazepam was given to weaned piglets intramuscularly (0.25 and 1.0 mg . kg-1), individually per os (2 mg . kg-1), or in feed mixture (5, 10, 15 mg . kg-1 of feed) either alone or in combination with phenobarbital (100 mg . kg-1 of feed). The highest tranquillizing effect of diazepam was obtained after the single administration of the intramuscular dose of 1 mg . kg-1, oral dose of 2 mg . kg-1, and after the intake of 0.65 mg together with 6.5 mg of phenobarbital per kg of body weight in feed during 22 hours. Adrenocortical activity, increased in the controls as a result of the stress from handling, was also blocked in these cases. The piglets which had consumed a dose of 0.66 mg of diazepam with feed during 14 days after weaning, or 0.26 and 0.34 mg of diazepam together with 5.2 and 3.4 mg phenobarbital per kg b. w., showed a manifest trend to a lower level of plasma corticoids. At repeated administration, the effect on body weight gains was not explicit; the addition of phenobarbital had no effect. No symptoms of intoxication or impairment to the metabolism of the main nutrients and vitamin A were observed. The suitability of diazepam for the tranquilization of piglets was demonstrated and the practical advantages of its administration in feed mixture were emphasized, the best time of administration being a day prior to handling which is expected to exert an adverse effect on pig production and to render human work difficult.