Seasonal variations in spermatogenesis, testicular weights, vasa deferentia, and androgen levels in neotenic male tiger salamanders, Ambystoma tigrinum.

@article{Norris1985SeasonalVI,
  title={Seasonal variations in spermatogenesis, testicular weights, vasa deferentia, and androgen levels in neotenic male tiger salamanders, Ambystoma tigrinum.},
  author={D. O. Norris and M. Norman and M. Pancak and D. Duvall},
  journal={General and comparative endocrinology},
  year={1985},
  volume={60 1},
  pages={
          51-7
        }
}
Significant seasonal changes were observed in spermatogenesis, testicular weights, vasa deferentia, and cloacal development as well as in plasma androgen levels (testosterone and dihydrotestosterone). Androgen levels were highest in the fall and lowest during the period of spermatogenesis. Low levels of androgens were also observed during the breeding season. Diameter of the vasa deferentia corresponded to presence of stored spermatozoa and not to plasma androgen levels. Testicular weights were… Expand
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