What are the prevention and control methods for abdominal distension and ulceration disease in large yellow croaker?
(1) Pathogen According to reports from Japan, it is Vibrio alginolyticus; but another source says it is Edwardsiella.
(2) Symptoms The stomach sac of diseased fish is especially swollen and enlarged, and in some fish the dorsal and ventral walls rupture from the swelling, with the entire stomach sac detaching from the fish body. Large numbers of diseased fry float scattered on the water surface, unable to feed, spin in circles for several days, then sink and die. Larvae at 15-20 days of age are most susceptible, showing a peak mortality period.
(3) Prevention and control methods Increase the water exchange rate, improve the rearing environment, avoid feeding Artemia nauplii alone, feed copepods earlier, strengthen the nutrition of larvae and juveniles, and strictly control water quality.