Testosterone-LH response and episodic secretion in the male marsupial, Dasyurus viverrinus

The pattern of testosterone-LH secretion, feedback mechanism, and periodicity of release were investigated in the male marsupial eastern quoll. Testosterone secretion is controlled directly by LH and in the wild, the secretion of both are synchronous and show a major peak at breeding time. An inverse relationship between the secretion of LH and testosterone occurs after castration which supports the hypothesis that a negative feedback mechanism exists between the gonads and the pituitary gland as in other mammals. These hormones fluctuate in a cyclic manner over 24 hr.