The phenomenon of mass fish deaths in cages and rafts on the Ma River is not due to disease.

After receiving information about the mass death of fish in cages and rafts on the Ma River through Ba Thuoc District for unknown reasons, the Department of Agriculture and Rural Development and specialized agencies have stepped in to determine the cause. Initial findings indicate that the fish deaths were not caused by disease.

Dead fish on Ma River do not show clinical signs of infectious disease.

According to the report, the phenomenon of fish dying sporadically and in small numbers in some households raising fish in cages and rafts in Canh Nang town since March 20 and then fish dying in large areas in the communes of Thiet Ong, Ban Cong, Ai Thuong, Ha Trung, Dien Lu, Luong Ngoai, Luong Trung and Canh Nang town. The total number of damaged fish cages was 210 cages of 158 households out of 692 households; the weight of dead fish was more than 12.1 tons.

In addition to Ba Thuoc district, since May 3, on the Ma River section flowing through Cam Thanh commune (Cam Thuy), there has also been a phenomenon of dead grass carp in cages. The total loss is about 972.3 kg belonging to 21 cages of 7 local households.

Professional agencies took fish and water samples to verify the cause.

Through the results of the actual inspection of the Department of Animal Husbandry and Veterinary Medicine, the Department of Fisheries and the People's Committee of Ba Thuoc district, it was shown that: The dead fish on the Ma River flowing through Ba Thuoc district did not show clinical signs of infectious diseases, parasitic diseases, or fungi on fish. When dissecting, the internal organs were completely normal; the dissolved oxygen index (DO) measured at the time of the fish deaths was from 3.1-3.3 mg/l, lower than the appropriate threshold; after instructing people to move the fish to other water sources such as near the mouth of streams, ditches, ponds and increasing oxygen or pumping clean water from wells and drilled wells into the cages, the salmon returned to normal.

The results of analysis and testing from 3 fish samples and 6 water samples also showed that no infectious diseases, parasites, or fungi were detected in the dead fish samples and that there was a lack of dissolved oxygen in the water (DO) that caused the fish to die.

After moving the fish to another water source such as near a stream, ditch, pond, and adding more oxygen or pumping clean water from a well or drilled well into the cage, the salmon returned to normal.

To promptly overcome the consequences of damage and soon stabilize production, the Department of Agriculture and Rural Development requested Ba Thuoc and Cam Thuy districts to strengthen monitoring to detect cases of dead animals and aquatic products; promptly implement remedial measures and handle to reduce damage.

At the same time, instruct people to implement technical measures such as moving and cleaning cages, using pumps and aerators to increase dissolved oxygen; if fish continue to die, collect and treat dead fish according to regulations, ensuring environmental hygiene and veterinary hygiene.

Along with that, local People's Committees need to coordinate with functional agencies to increase the frequency of environmental monitoring and supervision to provide early warning to people, minimize economic losses, and ensure people's health.

Le Hoa

Source: https://baothanhhoa.vn/hien-tuong-ca-chet-hang-loat-tai-cac-long-be-nuoi-tren-song-ma-khong-phai-do-dich-benh-213624.htm