Diagnosis and treatment of similar diseases in grass carp

For grass carp diseases with similar symptoms, if we can not distinguish between diagnosis and treatment in time and apply medicine blindly, it will often fail to achieve the desired prevention and control effect, and even aggravate the disease and affect the efficiency of culture.

1. Bacterial Gill rot and Gill mildew. The common characteristics of diseased fish are Gill flap damage, decay and whitening. The main manifestations of bacterial Gill rot disease fish are: Gill filament rot and whitening, Gill tip cartilage exposed, with sludge and yellow mucus, hyperemia in the inner epidermis of the operculum, and the surface is often corroded into irregular transparent holes. The main manifestations of Gill mildew disease fish are as follows: punctate bleeding of Gill flap, whitening and decay of some Gill filaments.

2. Enteritis hemorrhagic disease and bacterial enteritis. The common feature of diseased fish is intestinal congestion and inflammation. The main manifestations of enteritis type hemorrhagic disease fish are as follows: local or whole intestine is bright red due to bleeding, intestinal wall microvessels are particularly obvious, intestinal congestion but not decay, toughness, oral bleeding. The main manifestations of bacterial enteritis are as follows: all the intestinal congestion and inflammation is purplish red, especially near the anus, the mucous membrane of the intestinal wall fester and suppurate, abdominal enlargement has erythema, and there is yellow ascites in the abdominal cavity. Enteritis hemorrhagic disease can be vaccinated with inactivated vaccine of grass carp hemorrhagic disease.

3. White head and white mouth disease and rotifer. The skin of the head and eyeball area of the fish with white head and white mouth disease becomes milky white, the lips are swollen, the surrounding skin is rotten, and flocs adhere. Rotifer fish are pale white around the head and mouth, with a layer of white powdery substance on the head and secrete a lot of mucus.