Because Penaeus vannamei has the characteristics of high yield, rapid growth, strong disease resistance, high survival rate, and a wide range of suitable salts, the breeding and seedling raising technology has basically matured. Therefore, in recent years, aquaculture has developed rapidly. According to incomplete statistics, the area of ​​freshwater aquaculture in the Guangxi Sea last year reached 100,000 mu and the output was 15,000 tons, which accounted for 50% of the total shrimp aquaculture production in Guangxi. This year it is estimated that the first aquaculture area will be around 20,000 mu; Guangdong, Hainan The area of ​​freshwater aquaculture in the sea is estimated to account for 50% of the original aquaculture area, and Shanghai also has aquaculture area of ​​40,000 mu. It is reported that there are still many provinces and cities to promote the breeding of white shrimp this year. However, according to our years of experience in the promotion of aquaculture, the development of white shrimp culture in South America, we should pay attention to the following issues: 1, seed problems: the current seed supply is in short supply, stocking specifications. Last year, the nauplii of P. vannamei from Guangdong, Guangxi, and Hainan provinces were mainly supplied by Taiwan-funded plantations, and the source of broodstock was insufficient. The output of nauplii was still very low. This phenomenon caused the shortage of seedlings at the peak of release. Shrimp seedlings are naturally becoming smaller and smaller in size due to the rush of shrimp farmers. This year, many seedlings farms are turning to produce white shrimp seedlings of South America, and germplasm is inevitably uneven. Breeders should pay attention to selection. 2. Technical issues: The time of introduction of white shrimps in South America is rapid and the development is fast. Most farmers have not yet mastered the breeding techniques of this species, and they have guided, managed, and cultured the white shrimps of Penaeus vannamei, resulting in the release of some shrimp ponds. Post-emergence mortality is high and even the entire army is ensconced. A large number of deaths are still occurring when the shrimp specifications are 80-100fely> kg or more in the late aquaculture period. Farmers should pay attention to learning new technologies. 3. Feed issues: At present, there are not many special feeds for white prawn in South America. Many farmers use white prawn feed to feed P. vannamei, failing to give full play to the potential of the varieties' excellent characteristics and improving the economic benefits of breeding. Therefore, special feed for white shrimp should be used. 4. Environmental issues: Penaeus vannamei has poor adaptability to climate and drastic changes in the aquaculture water environment and has a strong stress response. In case of adverse weather such as cold air, typhoon and continuous rainfall, and excessive water quality, low pH (pH 8.0 or less), or a large amount of water change (more than 50%), the stress response of Penaeus vannamei is as follows: The tentacles and tails turn red. 2 Do not eat, swim wildly along the pond. 3 Extremely frightened jump. 4 prone to jaundice, black sorghum, broken phenomenon. In addition, Penaeus vannamei is not suitable for fertilizer and aquaculture, and it is necessary to maintain clean water quality during the whole breeding period. In particular, when the shrimp is in the pond, if the water quality becomes too fat, soft shell disease will occur, which will seriously affect the survival rate of the culture; if the water is too late in the rearing period, the shrimp After being frightened, the muscles became cloudy and turbid, and the convulsions sank to the bottom of the pool and died.
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