How to judge fish pollution poisoning

Fish death may be caused by disease, hypoxia, poisonous algae, mechanical injury, pollution poisoning and other causes, and pollution poisoning is the most common cause of death. The following introduces several naked eye judgment methods of common pollution poisoning for reference in production.

Heavy metal pollution poisoning. Heavy metals refer to metals with relatively high density, such as lead, manganese, zinc and so on. The gills of poisoned fish are grayish white and secrete a large amount of mucus, forming flocculent deposits, which block fish gills and cause respiratory disorders. Poisoned fish often float on the surface of the water.

Lead poisoning in fish, the body color is obviously black. Fish copper poisoning, the body color is grayish white, Gill filaments are light green. Fish chromium poisoning, the body surface is dark yellow, Gill filaments are yellowish brown.

Pentachlorophenol sodium pollution poisoning. Pentachlorophenol sodium is the most common organochlorine compound, which is mainly used as cercaria control drugs, and it is also a kind of insecticide. The fish poisoned by pentachlorophenol sodium swim rapidly, jump up and down aimlessly, and the poisoned fish have the habit of getting into the grass and close to the shore before they die. In general, wild miscellaneous fish die first, then silver carp, silver carp, grass carp, carp, crucian carp and other fish die one after another, and the body color of the fish turns black after death. The fins of chronic poisoned fish become black and exophthalmos are exophthalmos.

Methamidophos pollution poisoning. Methamidophos is an organophosphorus pesticide, which is commonly used as an insecticide. The poisoned fish are restless, swim slowly after the frenzied collision, appear lateral swimming, head down, tail up and other symptoms, and finally sink into the water and die.

Dimethoate pollution poisoning. After dimethoate poisoning, the symptoms were not obvious, but the liver of the fish was obviously enlarged.

Carbofuran poisoning. The main symptoms of fish poisoning are the bending of fish body and the formation of "trailing" excreta outside the anus.

Pyrethroid pesticide pollution poisoning. Pyrethroids pesticides are highly efficient, low toxic and low residual pesticides, but they are still highly toxic pesticides for fish, and they act quickly and kill greatly. Fish poisoning shows restlessness, Gill cover open, from fish whitening to death struggle time can be as long as 12 hours. After the fish died, the exophthalmos were exophthalmos, the fundus had bleeding spots, the abdominal cavity had stagnant water, and the Gill was gray.

Herbicide contamination, poisoning. Herbicide has contact killing effect and has low toxicity to fish, but it can still cause acute poisoning and death of fish when the concentration is high. Due to the killing effect of herbicides on algae, the polluted fish ponds are easy to lack oxygen, the phenomenon of dead fish will occur at any time of the day, the transparency of the water body will be greatly increased, and the phytoplankton in the water will basically disappear.