Prevention and treatment techniques of several common diseases in cultured California perch

California perch is extremely resistant to disease, so the incidence of disease is quite low. The following diseases are known so far:

1. Needle disease (anchor head disease): this disease occurs only in a few individuals, and most of the parasitic sites are at the base and tail of the dorsal fin or Xiamen fin. The affected part often has congestion, and the appetite of the diseased fish is slightly poor. The treatment is to catch the diseased fish, remove the needle worm, disinfect the wound with 10 mg / L potassium permanganate, or speed up the replacement of new water to prevent it from spreading.

two。 Water mildew: the main reason for the occurrence of this disease is due to the decrease of water temperature and infection caused by water mold when the body has wounds or scales falling off. There are cotton floc-like white villi in the diseased area. the disease is severe and has no appetite, and eventually dies. The preventive method is to avoid fishing in the cold, or to avoid fish injury or scale shedding as far as possible. When this disease occurs, it can be disinfected with 1 mg / L malachite green solution. However, it should be noted that the disinfection time is inversely proportional to the water temperature. The higher the water temperature is, the shorter the time is, and the lower the water temperature is, the longer the time is. If the water temperature is about 20 ℃, the disinfection time is 15-20 minutes, once a day for 3-4 days.

3. Blindness: mainly due to the whiteness and turbidity of the eye mask of diseased fish, unable to eat and finally die. The cause of the disease is eye damage while fishing. Therefore, it is especially necessary to prevent the eyes from being hurt when catching.

4. Bone flexion disease: abnormal bending of the vertebrae of fish. The cause of the occurrence is not clear, it may be caused by abnormal division of fertilized eggs during hatching, and there is no treatment. The growth of fish in this state is quite slow, so it is not suitable for breeding and should be eliminated when breeding.