Spermatogenesis in little tunny Euthynnus alletteratus (Rafinesque, 1810) fished on continental shelf of Côte d’Ivoire

Abstract

Testes of 406 males little tunny ( Euthynnus alletteratus ), collected over a year period from an artisanal commercial fishery, were used to morphologically and histologically assess patterns of the reproductive biology in this small tuna. Most of the specimens examined ranged in size from 35 to 82 cm FL (centimetre fork length). Observation of slides under a light microscope revealed that males investigated have lobular testicular structure. These lobules arrange in a branching system of tubules. Tubules join side by side to one another and yet inter-tubular-spaces separate them. Gametes’ developmental stages occur within such a structure. Histological characteristics were consistent with the description of the six-maturity stages of males little tunny determined on the basis of the macroscopic observation.