Treatment of several diseases of Pseudosciaena Crocea

1. White spot disease (stimulating cryptonuclear disease) 1. Pathogen: stimulating cryptonuclei, also known as "marine fish melons", belongs to the ciliate phylum of melons. The body is oval or spherical, and there are uniform cilia on the surface of the whole body.

two。 Symptoms: the worm is mainly parasitic on the body surface, gills and fins of Pseudosciaena Crocea. In the early stage of the disease, white spots can be seen on the caudal and pectoral fins of diseased fish. With the development of the disease, the white spots gradually spread to the body surface and Gill, and the white spots increased to form a membrane, commonly known as "white spot disease". The sick fish swim impatiently along the pond wall, or jump out of the water, or hit and rub against the pool wall. in severe cases, the scales fall off, the muscles are inflamed, fester, the eyes are white, the appetite decreases, the body is emaciated, and the movement is slow. Finally, due to serious damage to Gill tissue, breathing difficulties, asphyxiation to death.

3. Epidemic situation: from the middle of March to August every year, the water temperature of 15: 30 ℃ is the most popular. The water temperature of the nursery room is 25-30 ℃, especially for the fry over 20 days old, when the water exchange volume is less than 4 / 5, it is most likely to occur, and the infection rate is fast, the mortality rate is high, and all the fry can die within 1-2 days.

4. Prevention and control measures: 1) Prevention and control measures: ① for ponds, indoor breeding waters, increase water exchange, improve water quality, regular disinfection; sand filter should regularly sprinkle formalin for insecticidal disinfection.

② nursery appliances are often washed and disinfected with formalin or potassium permanganate, and used for special purpose.

The transmission rate of ③ increases with the increase of fish stocking density, so the stocking density should not be too high.

④ should strengthen nutrition and feed full-price feed to improve the resistance of fish.

2) treatment: ① diseased fish were treated with 0.6~0.7mg/LCuSO4 medicine bath for 12 hours for 18 hours, or 10mg/LCuSO4 medicine bath for 10 minutes for 20 minutes. After a large amount of mucus was discharged, the whole pond was absorbed and the water was changed thoroughly or the fry was poured out. The survival rate of fish fry is about 70%.

② bathe the fry with 20~30mg/L formalin for 20 hours or 24 hours, thoroughly change the water or pour the pool.

③ bathe the fry with 100mg/L formalin for 3 minutes for 5 minutes, then move to a clean seawater pool. The general cure rate of timely treatment can reach 70.90%.

④ was soaked with 50ppm for 5 minutes and 8 minutes.

⑤ blue and white film hanging bags: the blue film (Chong Chong No. 1) and white film (Nong Kangbao No. 1) were mashed and bandaged with 60-mesh silk mesh and hung at the underwater 30cm at the four corners of the Miao pond. A 50m3 seedling pond hangs 2 or 4 tablets at a time. The place where the medicine is hung must not be fed. When absorbing dirt and changing water, the medicine bag should be put away.

2. Enteritis 1. Pathogen: the disease is mainly caused by a variety of infections such as Aeromonas hydrophila and Vibrio. It is mainly due to the feeding of stale or spoiled bait, incomplete disinfection of environment and feeding utensils, and overfeeding of fish, etc.

two。 Symptoms: in the early stage of the disease, the diseased fish turned black, traveled alone and lost their appetite. In the later stage, the symptoms were abdominal swelling, anal redness and swelling, blood loss and whitening of the gills of the diseased fish. Autopsy showed congestion and inflammation of the intestinal wall, ulceration and exfoliation of the intestinal mucosa, and the intestines were filled with yellowish liquid and filled with water.

3. Epidemic: the spring seedling breeding stage mainly occurred, the epidemic season was from April to September, and the peak period was when the water temperature was higher than 25 °C to 30 °C. The course of the disease is short and can cause a large number of deaths within 3 to 5 days, with a mortality rate of more than 50% in severe cases.

4. Prevention and treatment: drug immersion is strictly prohibited for prevention and treatment of the disease. ① does a good job in environmental hygiene and disinfects the feeding utensils before each use.

The ② bait should be fresh, and the feeding taboo should be increased and decreased sharply.

③ high temperature period to control the amount of feeding: should be controlled at 7: 8% full, do not eat.

When ④ disease is prevalent, 20.4% allicin is added to the diet and reduced meals are carried out, and feeding can be suspended if necessary.

3. Benedeniasis 1. Pathogen: the pathogen is Benedenia, a class of paragonimus, oval flat, white, 6-7 mm long, visible to the naked eye.

two。 Symptoms: the worm parasites in the mouth, eyes, body surface, fins and other parts of the fish, showing a white transparent shape, the size of sesame seeds, also known as "white sesame disease", "termite disease". When the number of worms is large, it is white-spotted, which is attached to the skin or under the scales of the fish, and ingests the blood cells of the epithelial cells of the fish, causing trauma to the fish. The diseased fish secrete too much mucus on the body surface, restless, constantly swimming or rubbing against the net wall, so that the scales fall off and cause infection. The sick fish lost their appetite and finally died of wasting and exhaustion. The body surface of the dead fish is dilapidated, the mucus increases, the scales fall off, the eyes are damaged, the fins are incomplete, the gills are dark red and the fish are emaciated. The diseased fish can be seen to fall off by soaking in fresh water for a few minutes.

3. Epidemic: September to November is the popular season, in the autumn seedling cultivation stage, often mixed with stimulation cryptosporidium, anchor head worm infection, aggravate the disease, if not timely treatment, can cause a large number of deaths in a short period of time.

4. Prevention and treatment: the most effective method of ① is to soak the diseased fish in fresh water for 20-40 minutes, divided into three times, each time for about 10 minutes.

② was bathed with 150~200ppm formalin for 20 to 30 minutes.

③ was fed with erythromycin bait according to the body weight of the fish for 5 days.

④ was soaked in 30mg/L oxytetracycline for about 10 minutes and repeated after a week.

4. Valvular disease 1. Pathogen: the pathogen is Streptomyces punctatus. There is an oval nucleus slightly on one side of the middle of the body, and there are tufted cilia on the front and back. The worm can swim quickly in the water with the help of the swing of cilia.

two。 Symptoms: the valve worm parasites on the fish body surface, fins and Gill filaments, which increases the mucus secretion of the fish body, Gill anemia is gray-white, Gill filaments are swollen, there are many mud-like dirt, and there are irregular leukoplakia on the body surface. Loss of appetite, greatly reduced food intake, sick fish slowly swim away from the group, the body color becomes lighter, breathing difficulties, soon due to physical weakness and a large number of deaths.

3. Epidemic: the disease is prevalent from April to June, and the peak is when the water temperature is above 25 °C. it is a harmful parasite disease. It mainly harms the full-length 20~50mm fry cultivated in late spring and early summer. The disease has the advantages of rapid onset, short course of disease, high infection rate and mortality. If it is not treated in time, it can cause a large number of deaths, and the daily mortality rate of the disease can reach more than 10%.

4. Prevention and treatment methods: ① was washed with formalin seawater solution of 200~250ppm for 20 minutes, and the density was controlled at 25 ~ 35 tails / L, and aerated and oxygenated.

② prepared 20mg/L with furazolidone in fresh water and washed the diseased fish for 3 minutes for 5 minutes.

③ with cupric sulfate mixed with sea water to prepare 2mg/L concentration to bathe the sick fish for 10 minutes and 20 minutes.

After ④ washing, 20-30% antibiotics (such as tetracycline, erythromycin, etc.) were added to the diet for 5 days to recover.