New shrimp farming technique makes shrimp grow plump and strong

Xu Zhihua, a household in Fengma No. 1 Village, Hengli Town, Nansha District, Guangzhou, China@#@234@#@, contracted 60 mu of ponds to raise whiteleg shrimp (Litopenaeus vannamei). In 2007, under the guidance of agricultural technicians, he used enzyme bacteria technology and fish-and-shrimp fertilizer, achieving a net income of 5000 yuan per mu.

Xu Zhihua conducted comparative trials in two ponds. Pond No. 1 was sprayed with enzyme bacteria and fertilized with fish-and-shrimp fertilizer to enrich the water, with 50,000 shrimp fry stocked per mu. He applied fertilizer frequently and lightly, and throughout the whole process he used no water-purifying agents or bactericidal drugs, yet there was no shrimp surfacing or death, and the shrimp survival rate was above 95%. At harvest 4 months later, 1750 kg of shrimp were harvested, with about 800 kg still remaining in the pond. He obtained a net income of 5000 yuan per mu, with remarkable economic benefits.

Xu Zhihua's Pond No. 2 had an area of 5.5 mu and used the same batch of shrimp fry stocked at the same time as Pond No. 1, with the same stocking density, but it was managed by conventional methods. In early May, Pond No. 2 suddenly became covered with blue-green algae; the shrimp swam to the surface, stopped eating feed, and dozens of dead shrimp appeared at the pond edge every day. Xu Zhihua then applied enzyme bacteria and fish-and-shrimp fertilizer to Pond No. 2. Three days later, the blue-green algae were gone, the shrimp surfacing decreased, and the shrimp resumed eating feed; after May 23, basically no more dead shrimp were found. At the inspection on June 21, Pond No. 2 had already harvested 800 kg of shrimp for market, with about 750 kg still remaining in the pond, averaging 281.5 kg per mu. Pond No. 2 used relatively less feed, but drug costs increased, and the net profit was about 630 yuan per mu.

Under the conditions of the same batch of shrimp fry stocked at the same time and the same density, Pond No. 1 used enzyme bacteria and fish-and-shrimp fertilizer throughout the whole process, achieving good water cultivation results, a high shrimp survival rate and fast growth, and saving the cost of water-purifying agents, bactericides and other drugs as well as part of the feed cost. Its net income was 4370 yuan per mu more than that of Pond No. 2 under conventional management.