BANGLADESH: Fish inbreeding causes concern
Posted: October 30th, 2009 - 7:53pm
The current unplanned inbreeding of fish may cause genetic deteriorations in aquaculture production and open ocean fisheries, says Golam Hossain, Director General of the Bangladesh Fisheries Research Institute (BFRI). Hatchery stocks in floodplain and other open waters may be compromised.
"Unconscious negative selection of broodstock, mating of female and male spawns from a finite population and unplanned hybridization in hatchery stocks - especially carp - has created a widespread concern," Hossain explained.
In Bangladesh, fish production through artificial or induced breeding is a widespread practice, he said, The Nation reports.
About 1,000 hatcheries are responsible for over 95 per cent of the country’s total spawn production. Genetic deterioration has often been observed in hatchery populations through recent research, he noted.
Inappropriate management of broodstock and the mating of brothers and sisters or parents and their offspring have been damaging fishery populations, Hossain observed. Most commercial hatchery owners and employees are unaware of the consequences of using low-quality brood for breeding purposes, such as poor health and low weight of offspring, which results in high death rates, he said.
Many hatchery owners have been found guilty of uncontrolled hybridization between carp and ruhi, rui and mrigel and carp and mirror carp, often with dire results such as disability and susceptibility to disease.
By doing this, hatcheries enter the lucrative market of fish fry and fingerlings. The government has been running a fish releasing programme in the floodplain during every monsoon and extensively promoting aquaculture since 2007.
"If the unplanned trend persists, there will be an acute trouble in the gene introgression of the indigenous major carp species - ruhi, carp and mrigel," Hossain warned.
BFRI has been offering hatchery owners and others appropriate training. Even so, guidelines are not being followed, as it is more profitable to sell low-quality brood.
Meanwhile, there are 28 big and five small state-level hatcheries, 233 private hatcheries and 2,065 nurseries in the Rajshahi division, according to Divisional Deputy Director of the Department of Fisheries (DOF) Abu Baker Siddiqui.
To cope with this aquaculture crisis, Hossain has offered recommendations, such as the use of brood of suitable age and weight and proper trading of stock between hatcheries. He also recommended the production and collection of more brood from high-growing fingerlings and more harvesting from rivers.
Hatcheries and nurseries should be closely supervised to ensure they are adhering to the prescribed guidelines. All relevant government and non-governmental organisations should boost their efforts to push for ethical and planned breeding in the aquaculture sector, he said.