Insights into growth, gonadal development, and igf1 expression in captive false clown anemonefish (Amphiprion ocellaris): Implications for breeding programs and sexual development

Abstract

Understanding the interplay between growth and gonadal development is crucial for breeding programs and teleost sexual development. Here the growth and gonadal development of captive-reared false clown anemonefish (Amphiprion ocellaris) aged one to eight months was investigated. Histological analysis and quantification of insulin-like growth factor-1 (igf1) mRNA transcripts were performed. The fish displayed a maximum specific growth rate of 0.56 ± 0.11% day− 1 at two months with a negative allometric length-weight relationship. Gonadal differentiation occurred at three months, with concurrent oogenesis and spermatogenesis at four months. Male germ cell development intensified from five to eight months, at the stage of perinucleolus oocytes were observed. Expression levels of igf1 in the liver peaked at eight months; expression was highest in gonadal tissues at two months and decreased significantly in older fish. These findings highlight the potential role of igf1 in ovarian differentiation and the growth of primary oocytes. Further investigations are needed to explore the interplay between igf1 expression and other regulatory factors. This research enhances our understanding of fish reproductive biology and has implications for the captive management of false clownfish.