Applying science and technology to improve aquaculture productivity

Checking the quality of loach raised using the method of applying biological products. Photo: VNA

With the advantages of short farming cycle, high farming density, and being favored by the market, in recent years, many aquaculture households in Nam Dinh have adopted mud loach as their main fish. The whole province has hundreds of farming households, annually supplying about 300 - 500 tons of commercial fish to the market. However, the quality of parent fish is not guaranteed, along with environmental hygiene factors, making this species susceptible to disease during the farming process, and the yield and quality are not high.

After researching and surveying the production practices at seed production, nursery and commercial farming facilities in 6 districts of Nghia Hung, Hai Hau, Giao Thuy, Truc Ninh, Vu Ban, and Y Yen and evaluating the current situation, building a seed production process and commercial farming of mud loach, the research team of the Nam Dinh Province Aquatic Breeding Center carried out the project "Research on building a technical process for applying microbial products in seed production and commercial farming of mud loach in Nam Dinh province".

Engineer Vu Thi Bich An, Deputy Director of the Center, Project Manager, said that, in conducting the project, in addition to guiding households participating in pond renovation, the research team used BFC 02 pro microbial products to treat the water environment and BFC probiotic plus yeast mixed into fish feed. Accordingly, in 7 experimental ponds, the research team applied environmental microbial treatment once every 3 days and mixed probiotic yeast for daily feeding in 3 ponds, and once every 7 days treated environmental microbial treatment and mixed probiotic yeast for daily feeding in 3 ponds and a control pond, without using microorganisms.

Monitoring experimental ponds and control ponds, in the process of producing fish fry, raising fish fry to fingerlings and raising them for commercial purposes, the research team found that the survival rate of experimental ponds was higher than that of control ponds. In fish ponds using probiotics, the hatching rate and survival rate of fish fry were higher than those of control ponds.

In the experiments of raising fish fry to fingerlings in the spring-summer and autumn-winter crops of 2024, the highest and stable survival rate was 50% (twice the survival rate in the control pond).

Treating water environment in loach ponds with biological products. Photo: Nguyen Lanh/VNA

In the two commercial farming seasons in the summer-autumn and autumn-winter seasons of 2024, the applied ponds had an average survival rate of 69%. With 2,500m2 of ponds with a stocking density of 90 fish/m2, equivalent to 225,000 fingerlings, the ponds were treated with environmental microorganisms every three days and mixed with probiotics for daily feeding, yielding an average harvest of 2.7 tons of fish, earning a profit of 50.8 million VND/pond, while the control pond only yielded 1.6 tons, earning a profit of 5.6 million VND. This shows that probiotics have a great influence on the survival rate in the pond; at the same time, helping to decompose excess organic matter, stabilize the pond environment, release toxic gases, inhibit the growth of harmful microorganisms, and minimize fish diseases.

As one of the long-standing aquaculture households with a large area, Mr. Pham Duc Thuan, Phong Coc village, Minh Tan commune, Vu Ban district said that his family has more than 100,000m2 mainly raising koi fish and loach; of which, the area for raising loach is over 25,000m2.

According to Mr. Thuan, in aquaculture, using probiotics to treat the farming environment is mandatory. Especially for loach, if not using appropriate probiotics, it will be impossible to raise at high density.

In 2024, he and 15 members of Tan Khanh Production and Trade Cooperative applied the technical process of applying microbial products in seed production and commercial farming of mud loach fish researched by the Provincial Aquatic Breeding Center. Mr. Thuan assessed that, compared to other microbial products, BFC 02 pro and BFC probiotic plus are more effective. The pond water quality is more stable, the pond bottom is better improved, thereby improving the pond environment, less pollution, fish grow faster and have higher yields. With 25,000m2 of pond (7 acres), during the year, his family releases 2 batches of loach fish to harvest an average of 10 tons of fish/acre.

Currently, the research team of the Nam Dinh Province Aquaculture Center has completed three technical processes for producing fish fry, raising fish fry to fingerlings and commercial farming of mud loach. In the coming time, the research team will disseminate the results of the project to aquaculture households in the province, instructing people on how to renovate ponds, use microbial products as well as how to prevent diseases for farmed animals to improve the quality and output of products, towards sustainable aquaculture.