MYMENSINGH, May 06: Researchers at the Bangladesh Fisheries Research Institute (BFRI) have succeeded in artificial breeding of 24 endangered species of fish, including the endangered Tengra, Gulsha, Pabda and Bairali.
In this pandemic, scientists at the Freshwater Center of the Fisheries Research Institute have achieved this feat for the first time in the country.
As a result, the researchers hope that the endangered Dhela fish, which is rich in nutrients, can have very large production in the field very soon. Bangladesh Fisheries Research Institute (BFRI) Director General Yahya Mahmud said that for the first time in two years of intensive research at the Freshwater Research Center of the Fisheries Research Institute in Mymensingh, the minnows have been successfully produced through artificial insemination.
The research team was consisted ofthe chief scientific officer of the center AHM Kohinoor, Chief Scientific Officer Md. Shah Ali, senior scientific officer Selina Yasmin and scientific officer RabiulAwal. Dhela fish minnows collected from Brahmaputra river are reared intensively in the central pond. During rearing, the food and eating habits of the fish are monitored and food is provided according to the diet.
In addition, year-round GSI and histology tests determine the maximum breeding season for fish. Histological tests show that the highest breeding season for Dhela fish is May-June. However, the breeding season starts from the end of April. The egg bearing capacity of Dhela fish is 700-800 per gram. Studies have shown that a female fish weighs about 6-8 grams and is suitable for breeding. Reproductive males are relatively small (4-5 gms) in the size of female fish. In nature, males are relatively rare than females.
While collecting Dhela fish from different sources, it has been observed that the ratio of female to male Dhela in nature is 4: 1, there is only one male Dhela with four female Dhelas.On the research hormones were applied to 10 pairs of fish. After 08-09 hours of application of the hormone, the eggs are released and after 22 hours, the minnows are produced from the fertilised eggs. At that time the amount of egg fertilisation was about 80 percent. The minnows produced are currently being reared in the hatchery of the Freshwater Center of the Institute.
Dr. Yahya Mahmud said, "The introduction of minnow production techniques through artificial insemination of nutritious Dhela fish will facilitate the production and availability of Dhela fish minnow at the field level and will make it easier to bring Dhela fish under fishries."
He said that compared to other native fishes, Dhela fish has lots of minerals. Each 100 grams of fish contains 938 IU of vitamin A, 1270 mg of calcium and 13.60 per cent zinc. Which is much higher than other native fish. Vitamin A protects children from nyctalopia, and calcium helps build bones. Moreover zinc increases immunity.
Which is very useful during coronal period. A large quantity of Dhela were found in the country's rivers and haor, beels at one time. Later, due to climate change, over-harvesting and contraction of water bodies, the breeding and roaming areas of Dhela fish became extinct and this fish became endangered. As a result, Dhela fish is now almost scarce and sold in the market at high prices. With the invention of minnow production technology through artificial insemination by the institute, it will be possible to preserve the Dhela fish and increase its production through fisheries.