Reproductive biology and biochemical gonadal content of the spotted sand bass, Paralabrax maculatofasciatus in Kino Bay, Sonora

Despite the economic importance of sand bass, Paralabrax maculatofasciatus, little information regarding its reproductive aspects is known. In this study, gonadal maturity stage, biological indexes, proximate gonad composition and sex ratio proportion were determined. A total of 30 wild spotted sand bass were monthly obtained from March 2017 to February 2018. Organisms were measured, weighted and dissected in order to obtain the condition factor (K), hepatosomatic index (IHS) and gonadosomatic index (IGS). A small portion of gonad was preserved to perform the histological procedure, and stained with Harris' hematoxilineosin technique. The results indicate that somatic indexes were significantly affected (P<0.05) in terms of IHS and IGS. Histological analysis showed the presence of ripe males in April and from October to November, and for females, the presence of developed organisms was observed in April and from October to December. Additionally, the presence of transitional organisms from female to male was observed. The proximate analysis showed the maximum crude fat value in April, which coincides with the lowest moisture value. Sex proportion showed a significant male dominance. These data provide valuable information for the development of protection programs to encourage a sustainable fishery of the species.