Effects of β‐endosulfan on the growth and reproduction of zebrafish (Danio rerio)

Abstract

Because of persistent organic pollution in aquatic environments, the widely used organochlorine pesticide endosulfan, which is a potential endocrine disruptor, is expected to pose a significant risk to aquatic organisms. In the present study, we explored the potential endocrine-disrupting risk of β-endosulfan by investigating its effect on the growth, reproduction, plasma vitellogenin, and organ histology of adult zebrafish. We found that, although β-endosulfan did not significantly affect the growth of zebrafish, it greatly decreased the hatching rate, even at a concentration as low as 10 ng/L. Interestingly, the decrease of the hatching rate was highly correlated with pathological alterations of the testes. Additionally, the values of the gonadosomatic index were significantly reduced in female zebrafish treated with 200 ng/L β-endosulfan, which was also closely associated with ovarian histological changes. More importantly, a significant increase in the level of vitellogenin was observed in all male fish treated with β-endosulfan. Based on these findings, we conclude that β-endosulfan severely affects the reproductive function of zebrafish and the synthesis of vitellogenin in the liver, and thus, β-endosulfan has a serious endocrine disruption function in zebrafish.

Reproductive toxicity of chlorpyrifos tested in zebrafish (Danio rerio)

“…The results of this study are in concordance with earlier studies that demonstrated a dose-dependent increase in plasma VTG in male zebrafish exposed to -endosulfan (Han et al, 2011). Upregulation of messenger RNA expression of hepatic VTG1 and VTG3 in male zebrafish exposed to tribromophenol and 2,4-dichlorophenol was also noticed earlier Ma et al, 2012).…”

Exposure to agricultural pesticides impairs growth, feed utilization and energy budget in African Catfish Clarias gariepinus (Burchell, 1822) fingerlings

“…A study of Hanson et al (2007) showed the adverse effects of lindane, pentachlorophenol and propoxur on the growth of Nile tilapia, African catfish and Bagrid catfish Chrysitchtys nigrodigitatus. On the contrary a concentration of 10 ng/L of b-endosulfan did not affect the growth of zebrafish (Han et al 2011). Several factors can explain the delay observed in growth of fish exposed to the pesticides tested, such as the difference of feed intake (Wang et al 1998;Qian et al 2002;Lal et al 2013) or the difference in the food metabolism (Qian et al 2002).…”

The effect of vitamin E supplementation on ovary and testis histopathology inOreochromis niloticusexposed to deltamethrin

“…Mlambo et al (2009) reported that DDT exposure caused disorganization of seminiferous lobules in the testes of adult Mozambique tilapia (O. mossambicus). Testes degeneration and sperm necrosis were seen in the testes tissues of fish treated with beta endosulfan (Han et al 2011).…”

“…Atretic follicles were detected in the ovary of fish treated with beta endosulfan. These atretic follicles exhibited characteristic degenerative changes, including decreased vitellogenesis, oocyte membrane folding, and an increase in the number and size of follicular cells (Han et al 2011).…”