The Effect of Amprolium and of Payzone on the Functional State of the Thyroid in Growing Chickens

Abstract

The effect of amprolium and of payzone on the functional state of the thyroid in growing chickens. Acta vet. scand. 1973, 14, 225-228. -Amprolium fed to growing chickens in a concentration of 125 p.p.m, in a commercial diet was accompanied by a small but significant decrease in th yroid activity compared with the results for untreated chickens, judged by serum PBI values. The epithelium: colloid relation was lowered. This was presumed to be a con sequence of the antagonistic effect of amprolium on thiamine. Pa yzon e feeding, 10 p.p .m. in commercial feed, caused a more pronounced retardation of th yroid activity, judged by the same criteria. A possible connection between the depressed th yroid function and the well-established improvement in weight gain and feed conversion in connection with payzone feeding is discussed.

On the Effect of Payzone-Feeding on Some Blood Constituents of Growing Chickens

“…The mode of action of payzone [1,5-bis(5-nitro-2-furyl) 1,4pentadien-3-one amidinohydrazone hydrochloride] in improving the weight gain and feed conversion of chickens is not well understood. Andersson & Garry- Andersson (1973) found a depressed thyroid activity in connection with payzone-feeding, judged by changes in relative thyroid weight, epithelium: colloid relation and serum protein bound iodine (PBI). The increase in body weight might then, at least partly, be ascribed to a depressed thyroid activity.…”