Gametogenic cycle in Villorita cyprinoides and the influence of salinity
Journal Title: Aquaculture, Aquarium, Conservation & Legislation - International Journal of the Bioflux Society - Year 2009, Vol 2, Issue 4
Abstract
Villorita cyprinoides is gonochoristic and showed no signs of sex reversal and hermaphroditism. During the inactive stages of reproductive cycle the gonad is hardly visible through the visceral mass, but at advanced level it observed as a thick transparent tissue through the visceral epithelium. In Villorita cyprinoides the reproductive stages is classified into undifferentiated, early gametogenesis, late gametogenesis, mature, partially spent and spent stage. In undifferentiated phase the sexes are not able to distinguish even in smear preparation and hostological sections. At both stations the number of females are higher and Villorita cyprinoides breeds twice a year, minor spawning during December-February and major during May to July. There is a period of rest between two reproductive cycles; change in salinity is found to be the major factor which triggers reproduction and temperature was not at all a factor governs reproduction. Induced breeding of the species is possible either by sudden drop in salinity or increase in pH. Construction and periodical opening of Thannermukkom bund drastically affects the reproductive pattern of Villorita cyprinoides.
Authors and Affiliations
Aloorkalarickal Arun
Keywords
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