Control techniques of enemy diseases of river crab

The main enemies in the process of river crab culture are water rats, frogs, birds and so on, among which water rats are the most harmful. River crabs move on the slope of the pond at night, especially the soft-shell crabs that have just shelled, often move slowly for a few days and are most vulnerable to attack. Bait poisoning and artificial capture can be used for prevention and control.

There are several common diseases in river crab culture. in the stage of crab fry and juvenile crab, there are condensed worms and monozoan epiphytes, which seriously affect the normal activity and feeding of the larvae. In the young and adult crab stage, there are crab slave worms and red filariasis parasites. The former is parasitic in the abdomen, and there are white punctate worms in the navel of the crab. In serious cases, the meat smells foul and cannot be eaten. The latter is parasitic in the body and is visible to the naked eye. In addition, there is shell lysis disease, that is, there are holes in the crab shell; black spot disease, there are black spots on the crab body.

Once the river crab gets sick, it is very difficult to cure, so it is necessary to prevent the disease first and give priority to prevention. Before the river crab is released, it is necessary to thoroughly clear the pond, disinfect and kill germs. In the process of feeding, it is necessary to often add new water and sprinkle quicklime, so as to achieve better results.