Ornamental shrimp diseases are mainly divided into ten types, filamentous bacterial disease, black spot disease, bacterial necrosis, tired mycoccosis, muscle white necrosis, Dora virus disease, leukoplakia, red leg disease, carapace ulcer disease, black gill disease. Because the shrimp survive in the fish tank, and the water in the fish tank has become the key to the disease, the quality of the water leads to whether the shrimp can survive, but the water change is artificially controlled, so there can be no problem in the water quality.
Manning shrimp
1. Dora virus disease, referred to as TSV. When the water temperature reaches 28 ° C, the crystal shrimp is prone to disease. Symptoms of Dora virus disease: acute manifestations are weak and inactive crystal shrimp, soft carapace, empty stomach, jejunum, body surface is reddish, tail fan, swimming foot becomes red, shrimp die in large numbers during molting. Chronic manifestations are multiple damaging dark spots on the surface of the carapace, but can be ingested normally.
Second, leukoplakia is referred to as WSSV, and the manifestations and symptoms of leukoplakia are: the amount of food ingested by the diseased crystal shrimp is greatly reduced, and even stopped eating. Slow and sluggish movement, weak bounce. Float on the surface of the water or lie on the edge of the pool without moving. The cephalothorax and abdominal nails are easily peeled off, and the body color of the diseased shrimp often becomes slightly red or dull and faded, and the surface of the body adheres to the dirt. The white spots on the inside of the carapace can be seen directly to the naked eye.
Third, the manifestations of red-legged disease: the sick shrimp are inactive, swimming slowly or at the bottom of the water at the edge of the pool, sometimes swimming in rotation or vertical swimming. The response to external disturbances is sluggish, the appetite is reduced or the food is stopped, and the individual is more emaciated. The main symptom is that the appendages become red, the swimming foot turns red at the earliest, and the later foot and tail limb are also bright red, and the mortality rate of red-legged disease is higher, because it is an acute disease.
Fourth, the main pathogen of crustacean canker disease is caused by a variety of bacteria such as Vibrio, Pseudomonas, Aeromonas and slime bacteria. For crystal shrimp invaded by bacteria, the surface of its shrimp body will be mechanically damaged. Another is caused by a lack of vitamins. Carapace ulcer disease is the main symptom: the diseased shrimp move slowly, sometimes lose balance, swim sideways, crawl at the bottom of the pool, and finally die. If you look closely at the lesions of the shrimp body, you will find that the back of the first, second and third abdominal segments on the carapace on the side of the cephalothorax and the carapace on both sides and the caudal nodes have different degrees of black brown or black spotted ulcers, and the middle of the spots is concave, dark, and the edges are slightly white. Most of the newly dead shrimp have broken frontal swords, tail segments and appendages. The molted shrimp shell has a distinct black ulcer outline.
Fifth, Fusarium, deterioration of water quality, lack of vitamins can cause black gill disease. The main manifestations of black gill disease: the shrimp body produces melanin deposition, especially at the end of the gill filament, the dot or the whole gill is black, such as caused by bacterial invasion, when the hyphae grow in large quantities, they will break through the gill membrane and grow out of the gills, and resemble "flower" at the end of the gill filament. The diseased shrimp react slowly and travel sideways at the bottom of the tank.
Sixth, filamentous bacterial disease is also known as pathogenic bacteria. Characteristics of filamentous bacterial disease: filamentous bacteria mainly parasitize the body surface of shrimp larvae and juvenile shrimp, such as the bristles of the larval appendages and the ribs and feet of juvenile shrimp. If the shrimp body is viewed with a microscope, the bacteria can be found in the diseased part of the juvenile shrimp. When this filamentous bacterium parasitizes a large number of shrimp bodies, a large number of deaths occur.
Seven, the cause of black spot disease and black gill disease is similar, both are due to crystal shrimp disease caused by bacteria. Black spot disease is a more common type of crystal shrimp disease, mainly caused by bacteria that decompose chitin and decay, Pseudomonas and Caterpillar, etc., and the most deadly is the invasion of freshwater algal bacteria, resulting in the death of shrimp. Manifestations of black spot disease: smaller brown spots at the beginning of the disease, and then gradually ulcerate at the lesion and become black. The sites most commonly infected by bacteria are gill filaments, muscles on the ventral surface of the abdomen, caudal segments and foot walking feet. Severely ill shrimp are lying at the bottom of the tank, usually only the gastropods and gill caps are in motion.
Eighth, the pathogen of bacterial necrosis is more complex, there are many kinds of bacteria can cause this disease, the seat is not easy to judge. Manifestations of bacterial necrosis: the disease occurs mainly in shrimp larvae, and necrosis occurs in the appendages of diseased shrimp, especially the abdominal limbs of the antennae. The bacteria first concentrate on attacking 1-2 appendages, and then quickly cause the larvae to die. Sudden temperature changes and careless handling can also interfere with the immunity of the shrimp body and reduce the disease resistance of the larvae. Excessive larval density (100 pcs/L) and feeding underilized feed can cause bacterial necrosis.
The pathogen of mycoccosis is Epistylis of the protozoan phylum ciliosomes. Presenting features of mycoccosis: severely ill shrimp, often with villi on the body surface. This is the invasive twig insect, which will seriously affect the feeding of the shrimp body.
10. Muscle white necrosis is also known as muscle white turbidity disease. The cause of this disease is too high salt, too much density, too high temperature, dissolved oxygen and other adverse environmental stimuli caused. Vibrio infection or spore parasitism in the muscles can also occur. Muscle white necrosis is characterized by muscle necrosis in the last and second segments of the abdomen, gradually becoming opaque white (milky white), losing transparency, at first only the tail muscles become white, and then the muscles in the front of the shrimp body also become white. Individual diseased shrimp are whitened all over the body, and the muscles in the white area of microscopic examination have been necrotic, the muscle fibers are disordered, and the rhabdomy lines are not clear. Before the shrimp dies, the muscles are soft and the cephalothorax is separated from the abdomen. Giant shrimp with this disease have soft carapace, slow growth and high mortality. In water with a salinity of 35 ‰, the baby shrimp after the muscles turn white will die in about 1 hour. Muscle necrosis in male shrimp with larger individuals may be related to physiological factors. It is difficult to see sick shrimp on the surface of the water, and there are dead shrimp at the bottom of the pool, which are normal for early onset of disease, and after death, the muscles that turn white and turbid turn red first.