Investigating and monitoring the gonad development of Sewellia elongate Roberts, 1998 in captivity
Abstract
The study was conducted to investigate and monitor the gonad development of Sewellia elongate, which were collected in Binh Dinh province. The study consists of two stages: (1) Examining the population of wild fish in natural environment to predict the breeding season and recording the information of the species appearance by direct survey method at the distribution area; (2) Collecting and culturing the fish to monitor gonad development in artificial environment at Ho Chi Minh City. The result showed the wild population of Sewellia elongate spawned from April to June. In rearing condition, the average size of mature fish was 4-5 cm, while weighing between 3 and 5 g/fish. Monitoring the gonad development from June to August illustrated that males had testis and females had ovaries from stage II onwards - included the testis development was mainly in stage III, IV and V, ovaries development in stage II to V. Eggs and sperm were ready for reproduction in artificial condition.
