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Updated: Jul 23, 2026

Determination of Reproductive Competence by Confirming Pubertal Onset and Performing a Fertility Assay in Mice and Rats
Published on: October 13, 2018
[Hormones, reproductive behavior and fertility in male silver foxes]
Abstract:
The relationships between gonadal and glucocorticoid hormones and reproductive behaviour were estimated in two groups of silver fox males classified as either low or high sex activity. Levels of testosterone and cortisol in peripheral plasma measured by radioimmunoassay did not differ between the groups. However, when receptive females were introduced to experimental males, levels of testosterone in plasma increased significantly only in the males with high sex activity within 1 hr after a test of sexual behaviour. Low sex activity of silver fox males correlated with an increased level of aggressive behaviour and decreased fertility.
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