The present study reports the first incidence of intersex in Cobia, Rachycentron canadum maintained at sea cages in the Gulf of Mannar, India. During the 10 year study period (2010–2019), at total of 815 broodstock (386 wild captured and 429 captive raised) were maintained under captivity in sea cages in the Gulf of Mannar, India for the purpose of seed production. Of which, 318 male and 252 female broods’ gonads were examined post-mortem following a natural death. Only one male fish was found with a visible gonadal anomaly. Microscopic analysis of gonad revealed the presence of both the characteristic female and male tissues in testes of a single specimen (testis-ova). Only the abnormal nodular portion contained primary oocytes, whereas the central testicular tissue contained spermatocytes and spermatids in the seminiferous lobules. This is the first reported intersex of cobia from the Gulf of Mannar, India. It could be interpreted as low-level rare incidence of natural aberration.

本研究报告了双性恋在加拿大军曹鱼Rachycentron canadum中的首次发病维持在印度马纳尔湾的海笼中。在为期10年的研究期内（2010-2019年），在印度马纳尔湾的网箱中，总共815只亲鱼（捕获的野生野生动物和429只圈养的人工养殖）被圈养，以进行种子生产。在自然死亡后的尸检中检查了318个雄性和252个雌性性腺。仅发现一只雄性鱼类，可见性腺异常。生殖腺的显微镜分析显示，单个标本（睾丸-卵）的睾丸中同时存在女性和男性特征组织。仅异常结节部分含有原代卵母细胞，而睾丸中央组织在生精小叶中含有精母细胞和精子。这是印度曼纳尔湾首次报道的军曹鱼性交。