Does Castration in Guinea Fowls Produce Sexual Differentiation in Plumage and Changes in Head Furnishings?

Abstract

CASTRATION IN GUINEA FOWLS 653 tablets were given alone. There were variations both above and below the average curve obtained in the series which had received the Armour tablets alone, but the majority of the determinations as well as the average curve are somewhat higher in the series in which the KI was administered in combination with the Armour anterior pituitary tablets.Twelve guinea pigs were used in a series of experiments in which thyroid substance was administered alone in doses of 0.05 grain (Armour thyroid substance) and in combination with KI 0.05 gtn. Both drugs were administered daily by mouth. The average curve of the metabolic rates in the set of 6 guinea pigs in which the thyroid substance was given alone is very similar to that obtained when Armour anterior pituitary tablets were administered. There is a fairly sudden rise within the first 8 to 12 days which ranges from 35 % to 50% above the normal. This rise is followed by a fall which occurs in all the animals and ranges from 30% to 100%. After this there is a gradual and steady rise so that at the end of the 28 day period in which the animals were observed, the basal metabolic rate reaches a level approximately 50% above the normal rate. The animals which had received KI in combination with the thyroid substance showed in general a similar average curve of the metabolic rate to that obtained in those which had received the thyroid substance alone. There were variations in the determinations in the former series both above and below those in the latter series but the majority of the determinations as well as the average curve in the guinea pigs which had received thyroid substance with KI were slightly higher, especially in the latter periods, than in those which had received the thyroid substance alone.

Plumage tests in birds.

“…The plumage revealed no noticeable modifications. Krizenecky and Kamenicek (1932) gonadectomized five guinea cocks at the age of five months, three of which later proved to have been complete. Deplumed areas regenerated normal unmodified feathers in each case.…”