Analysis of fatty acids and sex steroid hormones in rainbow trout testes (Oncorhynchus mykiss) during the reproductive process
Rayees Ahmad Bhat Sudha Saini; Concetta Saoca; Giulia Maricchiolo; Francesco Fazio;
In the present study, we aimed to examine the cellular structure of the testes, the
hormonal changes occurring throughout the reproductive cycle, and the fatty acid
composition in rainbow trout. An electron microscopic analysis was conducted to investigate
the morphology and cellular changes during the development of the testes.
Germ cells were observed in different stages of differentiation: primary spermatogonia
(PSGs), secondary spermatogonia (SSGs), primary spermatocytes (PSCs), secondary
spermatocytes (SSCs), spermatids (SPDs) and spermatozoa (SZs). Differentiated
spermatozoa were observed within the cysts. Regarding steroid hormones, the maximum
level of testosterone was in the mature stage, and the minimum level was in the
spent stage; for 11-ketotestosterone,
the highest level was in the maturing stage and
the lowest level was in the spent stage. In terms of the fatty acid composition, the
levels of C14, C15, C16, C18, C16:1n7, C18:1n7, C18:1n9, C20:4n6, n-3
PUFAs, n-6
PUFAs, C20:5n-3
(EPA), C22:5n-3
(DPA) and C22:6n3 (DHA) (g-1 of gonad wet weight)
were the lowest during the immature stage and the highest during the mature stage
of the testes. The major significance of the study is the sex steroid hormonal profile,
the primary regulators of spermatogenesis and the fatty acid composition, which is
important for the development of gonads and sperm. These data should contribute to
the knowledge regarding the reproductive biology of male rainbow trout, for which
research data remain scarce.
2022 - Journal article
Aquaculture research (Print) (2022). doi:10.1111/are.15940
Keywords: 11-ketotestosterone, Fatty acids, rainbow trout, Sertoli cells, spermatogenesis, testosterone