Hormonal Profile and Reproductive Parameters of Pre-vitellogenic Mozambique tilapia (Oreochromis mossambicus) on Pawpaw (Carica papaya) Seed Meal

Abstract

The use of phytochemicals to control precocious maturation and indiscriminate spawning among tilapia species is an important issue in aquaculture. This study investigated the influence of pawpaw (Carica papaya) seed meal on the reproductive performance, and the sex hormone profile of sexually immature Mozambique tilapia (Oreochromis mossambicus). Pawpaw seed meal (PSM) were included in a tilapia commercial diet (basal diet) at an inclusion level of 0 PSM, 10 PSM and 30 PSM g/kg of the basal diet (BD), respectively, and fed to immature O. mossambicus for a period of 30 and 60 days, respectively. Enzyme-linked immune-sorbent assay (ELISA) procedures were used to quantify the plasma levels of 17β-estradiol and 11-ketotestosterone. The inclusion of PSM did not affect the growth and survival rate of the O. mossambicus. The plasma levels of 11-ketotestosterone did not differ among the treatment groups. The 17β-estradiol levels of female fish that received 30 PSM g/kg BD for 60 days were significantly lower (p < 0.05) than the levels reported for females that were not fed the PSM. In females, the PSM reduced the gonad weight, GSI, fecundity and egg diameter of fish. The study concludes that pawpaw seed meal affected the reproductive function of the female O. mossambicus though the changes were reversible.

Use of Pawpaw (<i>Carica papaya</i>) Seed in Tilapia Sex Reversal

“…In another research, Ugonna et al (2018) recorded 82.19% masculinization of Nile tilapia (Oreochromis niloticus) fed diet containing 4.27 g/kg PSM. It has also been reported that C. papaya seed included in the diet of pre-vitellogenic tilapia significantly reduced the 17β-estradiol levels, gonad weight, gonado-somatic index, fecundity and egg diameter of females (Abdelhak et al, 2013;Omeje et al, 2019). Most of the researchers (Ekanem and Okoronkwo, 2003;Hossam and Wafaa, 2011;Ampofo-Yeboah, 2013;Omeje et al, 2018) reported that the pawpaw seed meal were well tolerated by the fish and lesions (if any) it impacted on the tissues of fish were negligible and also reversible on withdrawal of treatment which shows that PSM is safe for use in tilapia culture.…”