A Detailed Guide to the Prevention and Treatment of Vibriosis in Farmed Pufferfish

[Symptoms of pufferfish vibriosis] The pathogen is Vibrio, with a growth temperature of 101Z-35C and an optimum temperature of around 25C; the growth salinity range is 0.5%-6%, and can even reach 7%, with an optimum salinity of around 1%; the growth pH range is 6—8, with an optimum of around 8. Diseased fish show gastrointestinal bleeding and inflammation, a reddened anus, and bleeding spots on the liver; the body surface becomes red from bleeding. Later, ulcers form in the dermal tissue, the bases of all fins become congested and red, the anus becomes red and swollen, the eyeballs protrude, with intraocular bleeding or bubble formation, or the eyeballs turn white and cloudy. The internal organs and muscle tissue show diffuse or pinpoint hemorrhages, the intestines show severe inflammation, and the intestinal mucosal tissue rots and sloughs off, forming yellow or yellowish-red mucus. The liver, kidney, and spleen bleed, and may even become necrotic.

[Prevention and treatment methods for pufferfish vibriosis] (1) Preventive measures for pufferfish vibriosis: ① Handle fish carefully to prevent injury to the body; ② Do not stock at excessive density; ③ Maintain good water quality and do not feed rotten or spoiled feed; ④ When using freshwater or 4% concentrated brine to remove parasites from the body surface of marine fish, antibiotics should be added to prevent bacterial infection; ⑤ If individual diseased fish are found, remove them immediately, keep them isolated, or destroy them; ⑥ Carry out artificial immunization. Before the disease season, feed each kilogram of fish 4 grams of formalin-inactivated Vibrio anguillarum vaccine daily for 15—30 consecutive days. This method is only effective in experiments, and further research is needed before use in production. (2) Treatment methods for pufferfish vibriosis: ① Pure antibiotic powders such as oxytetracycline hydrochloride, tetracycline, chloramphenicol, or chlortetracycline, at 50—70 milligrams per kilogram of fish per day; ② Sulfonamide drug powders such as sulfamerazine, or 4—sulfa—2.6—dimethylpyrimidine (long-acting sulfonamide), or 4—sulfa—6—methoxypyrimidine (sulfadiazine, long-acting sulfonamide C), at 200 milligrams per kilogram of fish per day, mixed into the feed and fed continuously for 3—7 days, all are effective, but when the water temperature is below 15°C the fish do not eat, so oral administration is ineffective; ③ Furazolidone sprinkled over the entire pond at a concentration of 0.5—1 milligram per liter.