June 1, 2018
A marine finfish hatchery project of the Rajiv Gandhi Centre for Aquaculture at Pozhiyoor , Kerala has reported a success in the production of Silver Pompano seeds by natural spawning in a controlled arena.
A high-prized genus, Silver Pompano (Trachinotus blochii) is emerging as a preferred choice for marine and brackish water aquaculture cross-wide nation.
RGCA scientists developed photo-thermal simulation systems which induced natural spawning in the Silver Pompano brood stock at the hatchery. “Though breeding programmes and seed production are being practised in the USA, China, Taiwan, Malaysia, Indonesia, Vietnam, and the Philippines, this is the first recorded production of Silver Pompano seeds from natural spawning in captivity,” says Geo Christy Eapen, project-in-charge, RGCA.
“Normally, spawning is induced by administration of reproductive hormones. The photo control method developed by us, along with careful nursing of brood stock and formulation of feeds enhanced the reproductive performance of the brooders, leading to natural spawning coinciding with lunar phases,” he explains.
This year, the project produced about 50,000 Silver Pompano seeds from five continuous natural spawnings. The first batch of seeds was sold to farmers in Andhra Pradesh. Farmers in Gujarat and Kerala have also taken to aquaculture of the species. In fact RGCA has launched a project to promote Silver Pompano farming in all maritime States. Also known as Valayod in Malayalam, the Silver Pompano attains a marketable size of 400 to 500 gm in around six months and can be cultured in floating cages or open ponds.
Preferred for its texture and flavour, the fish is usually sold as steaks or fillets for grilling or frying. It fetches Rs. 300 to Rs. 400 a kg in the domestic market against a production cost of less than Rs. 150 per kg, making it an attractive proposition for farmers.
Experiments at the RGCA hatchery revealed that the fishes are tolerant to even freshwater for a considerable period of time but prefer a salinity range of higher than 10 ppt (parts per thousand) for better growth.
The RGCA has tied up with the State Fisheries Department for sea ranching (release of juvenile fish into the sea) of Silver Pompano for natural stock enhancement. It has also established a multi-species demonstration farm at Muttom, Kanyakumari for cage farming of Pompano and Cobia (Rachycentron canadum).