Reproductive interventions for revitalising the sustainable production of Malabar labeo, Labeo Dussumieri, an indigenous candidate for aquaculture diversification

Malabar labeo, Labeo dussumieri is one of the cyprinids, endemic to the Western Ghats, India.The lack of availability of proper captive production techniques and over-exploitation has led to a decline in the population of this fish in its natural habitats.In the present study Malabar labeo were acclimatised to captive conditions and selected brooders were introduced into breeding pools.They were administrated with synthetic hormones for dose optimisation as well as breeding trial experiments.To determine the effective dose for induced breeding, the females were injected with WOVA-FH at 0.5 (T1), 0.75 (T2) and 1.0 (T3) ml/kg body weight.The spawning fecundity was 2.2 0.2 lakhs eggs/kg during the peak spawning season.Among the three treatments, T2 (0.75 ml/kg body wt.) showed the best results in terms of egg fecundity (89,560 592), fertilisation rate (94.76 0.57%), hatching rate (90.31 0.68%) and spawn survival rate (85.25 0.54%).The fertilised eggs were round, non-sticky with a diameter of 2.48 0.1 mm, and hatching took place between 16 and 20 h after fertilisation.The newly hatched larvae had an average total length of 4.1 0.2 mm and a weight of 2.7 0.4 mg.The study revealed the potential of producing L. dussumieri under captivity and meeting its demand for farming and conservation.