| Abstrakt: |
In the course of studies on the secretion of prolactin by goats in different physiological states, the concentrations of prolactin in the plasma of male goats were measured throughout the year.Three intact male goats aged 5½ (Miljohn), 2½ (Rupert) and 1½ (Minto) years at the beginning of the sampling period were used. The goats were maintained under the usual husbandry conditions, being turned out to pasture in the summer and kept in individual pens in a separate male goat house in winter; supplementary heating from infra-red lamps was used when necessary. During the breeding season, all three males were used to mate with females in the herd and all three were fertile. Samples of blood were withdrawn from a jugular vein once a week, between 14.30 and 15.30 hours for a period of 15 months. The blood samples were taken by venepuncture into heparinized syringes, centrifuged at 4°C for |
