What are the prevention and control methods for enteritis in yellow catfish?

(1) Pathogen: Aeromonas punctata.

(2) Symptoms: The diseased fish has a distended abdomen and red, swollen anus; when the abdomen is gently pressed, yellow mucus flows from the anus, and the diseased fish swims alone away from the group. When the abdomen is cut open, in mildly affected fish the esophagus and anterior intestine are congested and inflamed, while in severe cases the entire intestine is inflamed and pale red, with pus and blood filling the intestinal tract. Both fingerlings and adult fish can be affected.

(3) Harm and prevalence: Enteritis mainly harms yellow catfish fingerlings and adult fish. This disease is very likely transmitted directly by fish. Because the pathogenic bacteria can survive in pond silt, infection may also come from silt. In addition, the zooplankton and tubifex worms that the fish feeds on, as well as the fish meat paste in artificial compound feed, may also carry the pathogen.

(4) Prevention and control methods: ① Thoroughly clean and disinfect the pond and keep the water fresh. ② Disinfect live bait with 2%-3% salt water. ③ Strengthen feeding management and adhere to the “four fixed” feeding principles. ④ Splash the whole pond with 1 mg/kg bleaching powder. For every 50 kg of fish, use 250 g of garlic heads, mix with feed, and feed. Or when feeding fish meat paste, add 1% salt to the feed at a fixed point each day. ⑤ Feed sulfaguanidine medicated bait. The dosage is 10 g per 100 kg of fish on the first day, then halved each day from the second day to the sixth day. ⑥ Feed furazolidone medicated bait. The dosage is 4 g per 100 kg of fish on the first day, then halved each day from the second day to the sixth day.