Unknown disease takes toll on <i>koi</i> farming in Muktagachha
Fish farmers are incurring heavy losses due to epidemic deaths of climbing fish, locally known as koi, in Muktagachha upazila in the last two months.
The victims across the upazila blame adulterated fish feed for the endemic disease. The fisheries officials in the district headquarter however said they are investigating the matter and trying to find out the real cause through laboratory tests.
The hybrid species of the climbing fish, also popularly known as Thai koi, is cultivated in at least 25 villages of Muktagachha, sources said.
Farming of the fish started in the country about a decade ago and today over 20,000 farmers are involved in the trade in Muktagachha alone. Every farmer in the area has been affected by the plague which is depleting the fish stocks in the ponds, victims said.
Muktagachha upazila is also famous for shing (catfish) and pangas (Vietnamese river cobbler) cultivation but the recent epidemic deaths of koi has shaken the farmers' confidence.
Farmers said that the epidemic, that broke out in August, had already caused them losses worth lakhs of taka and if a cure was not found immediately the whole trade would be in danger.
Suruj Member of village Khilgati in the upazila said he cultivated koi in five ponds this year.
"All my stocks worth about Tk 5 lakh is dead," said Surju, adding that fearing loss, many farmers in the area sold off their whole lot of immature fish.
The affected farmers said they used fish feeds of different companies for koi cultivation.
"This year we found sand and rubber dust in the feeds of some companies and such adulterated feed is probably responsible for such deaths," alleged Humayun Kabir Mollah of Khilgati.
Shahjahan Siraj, another farmer, said they informed the fisheries department about the widespread deaths of fish. "We placed the matter before Muktagachha upazila fisheries officer several times but to no effect yet," he said.
The cost for production of one kilogram of koi stands at around Tk 160 inclusive of the price of fish feed.
"But we have sold one kilogram of fish at Tk 80 to Tk 100 only," said AZM Imam Uddin Mukta, another fish farmer.
Farmers, however, said that assistant upazila fisheries officer Ruhul Amin Faruq visited the spot and advised them to use lime and bleaching powder.
"We followed his advice but it did not work," said Mukta.
The farmers also alleged that there was no monitoring of the quality of the fish feed and so the feed traders were doing business at their will.
Contacted, district fisheries officer Suresh Chandra Sarker, told this correspondent a week ago that he along with two scientists of Bangladesh Fisheries Research Institute (BFRI), Mymensingh visited the spot on September 19 and collected samples of affected koi fish and water for tests.
Primarily it was found that water pollution due to indiscriminate use of feeds was the main reason behind such deaths. The farmers also cultivated fishes in their ponds often more than double their capacity, said the official.
"A farmer should cultivate 1000 to 1200 koi per decimal area of his pond but most farmers in Muktagachha cultivated 4,000 to 4,500 fishes per decimal," he said.
The leftover feeds got rotten and formed huge amount of ammonia gas in the ponds, resulting in epidemic deaths of the fish, the official said.
The fish sample is still being tested at BFRI laboratory and the report is yet to reach local office, added the official.
The allegation of adulterated fish feed would be probed and their samples have been collected for laboratory test, Suresh Chandra said.