The female reproductive cycle of the european common carp, Cyprinus carpio, at a Transvaal fish farm: Gonadal morphometric development

The annual reproductive cycle of Cyprinus carpio was investigated using morphometric parameters of the body and gonads, including fecundity estimations, gonadosomatic indexes as well as histological evaluation and classification of oocyte developmental stages. It was concluded the C. carpio has an extended spawning season under temperate conditions, from early spring (September) to late summer (February). Results further suggest that by manipulating temperature and daylight period during late winter (August) it would be possible to induce spawning during this period