Crucian carp boil disease causes red, swollen, congested body surface and pus-filled boils. How can it be prevented and treated?

    Crucian carp boil disease is caused by Aeromonas punctata f. furunculus. In the early stage of the disease, the skin and tissues on the back of the crucian carp become inflamed. As the disease progresses, pustules appear in the tissues of the inflamed area, and the affected part becomes raised, red and swollen, feeling soft and puffy to the touch. The pustules are filled with pus. The skin and muscle around the pustules also become inflamed and congested, and in severe cases, the intestines also become congested. The fin rays split, and the fin bases become congested. This disease has no obvious epidemic season and can occur throughout the year. After crucian carp are infected with boil disease, a treatment method combining external application of disinfectants and oral administration of antibacterial drugs can be used.

Crucian carp farming

   (1) External application of disinfectants. Add 0.3-0.5 g of chlorine dioxide or dibromohydantoin per cubic meter of water and splash it over the whole pond for 3-5 consecutive days; if the condition is severe, double the dose on the first day. After 1 course of treatment, wait 2 days, then splash 15-20 kg of quicklime per mu of water surface after slaking it into slurry over the whole pond, or add 2 g of bleaching powder per cubic meter of water and splash it over the whole pond. When the water is relatively fertile, add 15-20 ml of concentrated glutaraldehyde per mu and splash it over the whole pond for 3-5 consecutive days; when the water is relatively lean, add 0.3-0.5 g of strong chlorine essence (containing 40%-50% trichloroisocyanuric acid) per cubic meter of water and splash it over the whole pond for 3-5 consecutive days.

   (2) Oral administration of antibacterial drugs. For every 100 kg of crucian carp, mix 1-2 g of multivitamins and 2-5 g of norfloxacin into 5-10 kg of feed and feed it, twice a day for 3-5 consecutive days; or for every 100 kg of crucian carp, mix 5-10 g of Sanhuang powder and 10-15 g of sulfadiazine into 5-10 kg of feed and feed it, twice a day for 3-5 consecutive days; or for every 100 kg of crucian carp, mix 20-30 g of allicin and 5-10 g of sulfadimethylisoxazole into 5-10 kg of feed and feed it, twice a day for 3-5 consecutive days.

    To prevent crucian carp boil disease, do the following two things well:

   (1) Do a good job of pond clearing and disinfection. Use 150-200 kg of quicklime per mu for pond clearing with water, or 100-150 kg of quicklime for dry pond clearing. For ponds where boil disease has occurred, in addition to disinfection, they must also be exposed to sunlight for 10-15 days.

   (2) Shorten the transportation time of the fingerlings or adult fish to be stocked as much as possible, reduce mechanical damage, and strictly prevent diseased or injured crucian carp fingerlings or adult fish from being stocked into ponds. Fingerlings or adult fish must be disinfected, generally by soaking in a 20 mg/L potassium permanganate solution for 20 minutes, or by soaking in a 3%-5% salt solution for 15-20 minutes before stocking.