April enters the Qingming and rainy season, the rainfall increases and the weather becomes warmer, and the temperature and water temperature are obviously rising. The breeding species began to put seedlings one after another. After the overwintering period, the fish feeding activity gradually increased, and the residual bait increased. , The bacteria multiply faster. In early spring, the climate is changeable, the temperature difference is large, and the rain is frequent, and the water environment changes stress on the breeding organisms, prone to saprolegniasis and bacterial diseases. Therefore, disinfection and water quality control of breeding ponds and seedlings during the seedling stage should be done.
1. Illness prediction
1. Penaeus vannamei:Shrimp enterocytosis, white spot syndrome, etc. are prone to occur, and the focus is on the cultivation area of Penaeus vannamei in greenhouses.
2. Marine fish:prone to saprolegniasis, white spot disease of viscera, etc., focus on the sea cage culture areas in eastern Zhejiang and southern Zhejiang.
3. Freshwater fish:susceptible to parasitic diseases such as cucurbitaemia, trichoderma, gill rot and saprolegniasis, focusing on northern Zhejiang, Freshwater aquaculture areas in the middle and east of Zhejiang.
4. Soft-shelled turtle:Prone to bacterial diseases such as rot and ulcer disease, focusing on the breeding areas of soft-shelled turtles in northern and middle Zhejiang.
2. Prevention measures
(1) Preventive measures
1, vannamei white shrimp
After clearing the pond thoroughly, raise the water a week before the seedlings are released to stabilize the water environment; insist on introducing seed from a good seed farm or a reputable seed breeding farm. Choose healthy and vigorous high-quality seedlings, and ask for quarantine certificates as much as possible or conduct testing before seedling release to ensure that the seedlings that do not carry pathogens, are harmless, and are healthy. During the breeding process, water quality management should be strengthened, and high-quality and comprehensive feeds should be fed regularly, quantitatively and at multiple points to meet the nutritional needs of shrimp growth.
2. Visceral white spot disease of large yellow croaker
Do a good job in disinfection of cages; try to choose high-quality seedlings, pay attention to the temperature of the seedlings, keep the temperature of the seedling field and the sea area as consistent as possible, and do not release the seedlings too early , The water temperature is best to be above 15℃; control the stocking density to ensure the smooth flow of water in the cages and good water quality to reduce the impact of diseases.
3, freshwater fish gill rot, saprolegnia
Thoroughly clean the pond and expose to the sun before stocking; perform regular water quality and food table disinfection; during the artificial propagation of fry, the hatching equipment and fish nests must be disinfected , To prevent the occurrence of fish eggs and fry saprolegnia during the hatching process; when the fingerlings are stocked, soak them with 2%~3%salt water for 10~15 minutes.
4, turtle skin disease, fester disease
Outer pond soft-shelled turtles are poor after being consumed during hibernation, and they are prone to infections after the beginning of spring. Regular disinfection of the water should be noted; at the same time, vitamins should be added to the feed to enhance constitution.
(2) Treatment measures
Bacterial diseases of freshwater fish can be disinfected with national standard fishery chlorine and iodine disinfectants, combined with drug sensitivity test, select national standard fishery antibiotics such as florfenicol Oral treatment; protozoa such as trichosanthes and obliquus can be treated with copper sulfate ferrous sulfate powder; parasites such as sinensis and anchor head can be treated with refined trichlorfon powder and evenly splashed into the pond.
Visceral white spot disease of large yellow croaker:Combined with drug sensitivity test, select national standard fishery mixed feeding such as doxycycline hydrochloride.
soft-shelled turtle skin disease, ulcer disease, water products use chlorine-containing disinfectants to purify and disinfect water when the disease occurs, and at the same time add florfenicol and vitamin C to the feed .