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has been cited by the following article:

• TITLE: Induction of testis-ova in nile tilapia (Oreochromis niloticus) exposed to 17β-estradiol

  AUTHORS: Piya Kosai, Wannee Jiraungkoorskul, Chaivira Sachamahithinant, Kanitta Jiraungkoorskul

  KEYWORDS: Oreochromis niloticus; Nile Tilapia; Endocrine Disruption; Xenoestrogens; Testis-Ova; 17β-Estradiol

  JOURNAL NAME: Natural Science, Vol.3 No.3, March 31, 2011

  ABSTRACT: The efficacy of Endocrine Disrupting Compounds (EDCs), 17β-estradiol was tested on the fish Oreochromis niloticus in order to understand the intersex relationship of fish, in which sequential hermaphrodism can consist of a male changing into a female (protandry) or a female changing into a male (protogyny). The fish were equally divided into 3 groups. The first group was the control group; the second and third groups were treated with 10 and 100 mg L-1 of 17β-estradiol, respectively, for 30 days. The overall result in this experiment had no significant effect on the growth parameters. Among the two treated groups, the low concentration group shows results similar to those of the control groups. The high concentration group shows changes to the male reproductive system with the appearance of the testis-ova present resulting in an intersex condition of the male gonads. With this experiment, it can be concluded that 17β-estradiol at high concentration reveals positive changes towards the male reproductive system of the fish, Oreochromis niloticus.