Hot summer, is the best season to eat crayfish, but often reported on the Internet citizens eating crayfish poisoning news, also let the public worried. An Zhenhua, an aquaculture expert with the School of Animal Sciences at Yangzhou University, explained on Monday how to reduce the toxic bacteria in crayfish.

　　"Eating fresh crayfish is generally not toxic. When choosing crayfish, choose ones with clean limbs and head and lighter body color, which are less contaminated. If you eat dead shrimp, it will easily lead to diarrhea and other gastrointestinal infections, harm the health of the body, "said An zhenhua, who advises against eating crayfish yellow. Because of biological enrichment, 70 to 80 percent of the toxin is concentrated in the head of the crayfish, it is recommended to eat only the tail meat.

　　"If you are eating crayfish in restaurants, you should first observe whether the cooked crayfish are bright, curved and full, and see if the meat has a certain elasticity and chewiness," he warned. If there is a fishy smell, the body of the shrimp developed straight, the flesh soft and inelastic phenomenon, then it is most likely to be made by dead shrimp, do not eat."

　　If people cook crayfish at home, they must cook them thoroughly at high temperature, because only high temperature cooking can completely kill the parasites, and cooking time must reach 30-40 minutes to kill the parasites. If the use of roast, Fried or pickled, drunk and other methods of processing crayfish, after eating there is likely to be infected with lung paragonimiasis.

　　How do you reduce the toxic bacteria in crayfish? An zhenhua said that the summer and autumn season is the peak season for crayfish disease, which is mainly caused by high temperature and bacterial infection. High temperature environment is easy to cause the decrease of oxygen content in water, and the crayfish die of hypoxia. The bacteria infect the crayfish and cause a variety of bacterial diseases, the most common of which is aeromonas hydrophis. The crayfish with bacterial disease will generally have abdominal distension, no food intake, intestinal swelling, bleeding and other symptoms. However, because of their strong resistance, crayfish generally do not die suddenly.

　　"For farmers, the simplest precaution is to reduce the density. The density of crayfish should not be too high because they are 'mutually exclusive', with the average amount of crayfish raised in an mu pond no more than 10,000, "said An