The Effect of Habitat Manipulation on Early Gonad Maturation of Channa striata in Captive Condition

Abstract

Background: With remarkable growth in aquaculture, the need for system diversification and species diversification has been demanded by the producers to gain fruitful output in terms of profit. Striped murrel, Channa striata has been identified as a suitable species for modern aquaculture systems in terms of species diversification due to their fast growth rate, air-breathing nature, higher market price and consumer acceptance. The major bottlenecks in seed production of murrel are captive maturation and short spawning window. To overcome these problems, an attempt was made to achieve early gonadal maturity of striped murrel in captive conditions by intervening in the brooder rearing habitat. Methods: In this regard, four habitats were tested in duplicates, namely T1 - Tank with clean reservoir water without macrophytes and soil base, T2 - Tanks provided with floating (Water hyacinth, Eichhornia sp) and submerged (Waterthyme, Hydrilla sp) aquatic macrophytes without any soil base, T3- Tanks provided with only soil base (15-20 cm) without any macrophytes and T4 - Tanks provided with both soil base and macrophytes. Result: At the end of the three-months rearing phase, the fishes provided with macrophytes and soil base (T4) resulted in early maturation characterized by an egg size of around 1.29±0.21 mm and the majority of late granular stage oocytes and spermatozoa in ovary and testes, respectively. The results concluded that providing a bottom soil base of 15-20 cm and covering the 20-30% water spread area using aquatic macrophytes in the brood rearing tank helped in the gonadal maturation of striped murrel during pre-monsoon in captive conditions.