Bacterial Diseases of cultured Loach and its Control

Misgurnus anguillicaudatus is a warm water bottom fish, which has both edible and medicinal value, and is one of the main freshwater economic fishes in China. In recent years, due to the export of foreign exchange and the increase of market demand, the artificial intensive culture of Loach has developed rapidly, resulting in a variety of bacterial diseases. In this paper, the symptoms, etiology, prevention and treatment methods are summarized as follows, which can be used as a reference for breeders.

Red fin disease

1. The symptoms of this disease are mostly caused by the deterioration of water quality and improper storage, which are caused by Brevibacterium infection and are prevalent in summer. Diseased fish body surface or fin epidermis peeling off is grayish-white, anus is red, then erythema appears in the abdomen and side of the body, and gradually becomes crimson, intestinal erosion, and then parasitic water mold in the skin ulcer, causing water mildew. Sick fish hang on the water surface of the pool or near the pool edge and do not feed.

two。 The prevention and cure method uses 1 gram bleach aqueous solution per cubic meter of water body and sprinkles it in the whole pool. Or wash the fish with a solution of 10 mg ~ 15 mg chloramphenicol, oxytetracycline or chlortetracycline per + ml for 10 ~ 15 minutes, once a day, 1 ~ 2 days, and cured in 4 ~ 5 days.

II. Hemorrhagic disease

1. Symptoms of the disease have emerged in recent years, and exactly what kind of bacteria cause the infection remains to be confirmed. It is easy to occur from early spring to October. The body surface of Misgurnus anguillicaudatus showed punctate, massive or diffuse congestion and bleeding, and there was also bleeding in the internal organs, showing symptoms of septicemia.

two。 The control methods were sprinkled with bleach or sodium dichloroisonitrile in the whole pool, or fed with 10 mg ~ 15 mg oxytetracycline per kilogram of Loach.

Enteritis

1. Symptoms and etiology water temperature above 20 ℃ is easy to be prevalent, which is caused by intestinal type Aeromonas punctata infection. The intestinal wall of Misgurnus anguillicaudatus is congested and inflamed, the abdomen is dilated, there are erythema, the body color becomes black, the anus is red and swollen, the intestines are purplish red and there is yellow mucus. The disease is often associated with Gill rot and red skin disease.

two。 Prevention and treatment methods: sprinkle bleach or take furazolidone orally in the whole pool.

Fourth, Gill rot disease

1. Symptoms and causes when the culture density is high, the water quality is poor, and the water temperature is more than 15 ℃, the Loach body is infected with Flexobacterium columnar, which is caused by Gill tissue decay. The body color of Loach is black, the Gill filaments are rotten and white, the tip cartilage is exposed, there is mud and mucus on the gills, and serious cases will "open the skylight".

two。 The prevention and treatment methods were sprinkled with bleach or oral norfloxacin.