Spermatogenesis is a developmental process during which a small number of diploid
spermatogonial stem cells produce a large number of highly differentiated spermatozoa …

The major progestin in teleosts is not progesterone, as in tetrapods, but 17, 20β‐
dihydroxypregn‐4‐en‐3‐one (17, 20β‐P) or, in certain species, 17, 20β, 21‐trihydroxy …

Three major phases compose spermatogenesis: mitotic proliferation of spermatogonia,
meiosis of spermatocytes, and spermiogenesis, the restructuring of spermatids into …

Fish spermatogenesis, from spermatogonial stem-cell renewal to sperm maturation, is
controlled by the sex steroid hormones. Mitotic divisions of spermatogonia can be …

In teleost fish, sex steroids are involved in sex determination, sex differentiation, and fertility.
Cyp17a1 (Cytochrome P450 family 17 subfamily A member 1) is thought to play essential …

Meiosis is an indispensable process of sexual reproduction. However, detailed information
on the regulatory mechanisms that initiate meiosis is not available. Progestins are important …

Using two species of teleost fish, Japanese huchen (Hucho perryi) and common carp
(Cyprinus carpio), we investigated whether sex steroids are involved in early oogenesis in …

Abstract The Yakima River Spring Chinook Salmon Supplementation Project in Washington
State is one of the most ambitious efforts to enhance a natural salmon population currently …

In male salmonids, the age of maturation varies from 1 to 6 years and is influenced by
growth during critical periods of the life cycle. The endocrine mechanisms controlling …

Background Sex hormones play important roles in teleost ovarian and testicular
development. In zebrafish, ovarian differentiation appears to be dictated by an oocyte …