Autumn often outbreaks of various types of fish parasites including anchor flea, this type of parasite always has three forms, child worms, strong worms and old worms, of which strong insects are the most harmful to fish, but insecticide to kill child insects, for farmers who do not know how to kill insects, you can see this article, for reference only.
1. Manifest symptoms
The parasitic diseased fish of anchor-headed fleas manifest themselves in anxiety, food loss, and weight loss. "Child worms" are like fine hairs, without ovary sacs, and blood spots appear on the parts of the parasitized fish body; The body of the "zhuang worm" is transparent, the ink-colored intestinal peristalsis in the body can be seen, the ovaries occupy a prominent position on both sides of the intestine, and the posterior end of the body often has 1 pair of egg sacs, which can be erected when the insect body is moved by hand; The body of the "old worm" is cloudy and soft, and many tired branches are often born on the surface of the body.
Second, the characteristics
1. The insect body parasitizes in various parts of the fish body, showing a white line head, swimming with the fish. Some insects have cotton wool moss on their bodies, which are often mistaken for moss and hang on fish.
2, this pest is fierce and gluttonous, there will be irregular deep holes in the parasite, the head of the insect drills into the muscles of the fish body, sucks blood with the mouthparts, and also eats scales and muscles, and the wounds caused by it open the door to the invasion of water mold, wheel worms, etc.
Third, the three forms of anchor-headed fleas
1, the child insect body is as thin as hair, white and transparent, no egg yolk, the naked eye needs to be observed to see, generally 2-3 days after the development of strong insects. When child infections are the mainstay, insects can be killed twice in a half month.
2. The body of the strong insect is thick and transparent, the hand can be erected, the naked eye can see the black intestinal peristalsis, and a pair of green egg sacs are hung behind the body. When the infection of zhuang insects is the mainstay, the drug can be used once.
3, the old insect body color is cloudy, soft, inelastic to the touch, no egg sac, the insect body often attaches to a lot of protozoa of the fungus, the insect body is close to death. Mainly old insect infections can not be used.
Insecticidal:
Remember: we kill juveniles, juveniles, juveniles. Say important things three times! The effect is very poor in the adult stage.
When the ambient water temperature is 18-20 °C, it takes a total of 5-6 days from hatching of the oocyst to the first copepod larvae; When the water temperature is around 25 °C, it takes 3 days; When the average water temperature is up to 30 °C, it takes only 3 days. When the temperature changes too much, the development of the larvae will appear "hysterical". For the same developing oocyst, the rate of development and growth of its larvae is also uneven.
Taking organophosphorus as an example, after its hydrolysis can produce an inhibitor of cholinelithase, which is combined with cholinelipase in the insect body, so that the activity of cholinelipase is inhibited, and the ability to hydrolyze and destroy choleacetylcholine is lost. Due to the large accumulation of acetylcholine, the nerve function of anchor flea is abnormal, first excited, then paralyzed, until poisoning death.
When the water temperature is 25 degrees, when the fish body is found to have anchor-headed flea parasitism and hangs eggs, use organophosphorus 3-5 times continuously (because we can't be sure when it will reach the larvae).
If it is found to be an old worm, use organophosphorus 2-3 times continuously.
In addition, the host can also be selective according to the pathogen, and the rotation method can be used for prevention.
The use of copper sulfate and ferrous sulfate compound (the ratio of the two is 5:2) sprinkled throughout the pool, generally so that the pool water into a concentration of 0.7 g / cubic meter, the treatment effect is good. Sick fish can be bathed in an aqueous solution of potassium permanganate, and the concentration of the drug at a water temperature of 15 to 20 °C is 20 g/m3.
Anchor head fleas are easy to occur in autumn, because the water temperature adaptation in autumn, after a large number of bait, residual bait and fish excrement in the summer, so that the water quality is suitable for the growth of various parasites and pathogens, at this time, the anchor head flea is also waiting for the opportunity to move, infected with which low resistance or injured fish, so farmers should also pay attention to the market feeding to improve the resistance of the fish body medicine, reduce the probability of fish infection disease.
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