I. Overview of disease types of ornamental fish Generally, fish diseases are divided into two categories: one is mainly caused by living animals or plants. Diseases caused by viruses, fungi, bacteria and unicellular algae are also called microbial fish diseases. Microbial fish is called infectious fish disease because of its acute onset, rapid spread, high morbidity and mortality, strong infectivity and difficult prevention and control. Fish diseases caused by animal parasites are called parasitic fish diseases, which generally have the characteristics of slow onset and spread, low morbidity and mortality, and easy prevention and control. Another kind of fish disease is called abiotic fish disease, which is mainly caused by abiotic factors such as mechanical, physical and chemical factors of water environment or physiological dysfunction of fish. There are many kinds of fish diseases, which are harmful and involve a wide range. As long as management is strengthened and prevention work is done well, this kind of fish disease can be avoided.

Second, diseases caused by virus 1 hemorrhagic disease

[Pathogen] It is herpes virus.

【 Symptoms 】 The body surface of the diseased fish is dark and dull, and the mouth, muscles and various fin bases are congested. Sometimes there is congestion on the gill cover, head and abdominal wall; Branchial filaments are bright red spots or congested plaques; Seriously sick fish, due to a large amount of congestion in other organs and tissues, make their gills pale and "white gills". In addition, exophthalmos, intestinal tract and internal organs show congestion. Sick fish lose appetite, move slowly, often swim alone or slowly, lose weight, muscle atrophy and even die. The onset season is mostly from June to September, and the water temperature is 25 ~ 30℃, which is the most popular and the mortality rate is quite high.

[treatment method]

(1) Get enough sunshine and lower the water temperature below 25℃ for about 10 days, and you can see the curative effect.

(2) Take a bath with 1% salt water 1 week.

(3) Grinding 0.25-0.5 kg of rhubarb and 0.5 kg of Liquidambar formosana leaves into powder, decocting in water or soaking in hot water, then mixing with bait to make medicinal bait, and feeding the sick fish for 5 days, while using 0.6ppm of dichlorvos in the aquarium for 2 days.

(4) Water bath treatment with 3-5 ppm Dijunling, or 0.7 ppm copper acetate, copper chloride, copper sulfate solution, or rhubarb extract has better effect. 2. Vaccinia-also known as lymphocystis disease virus's disease.

[Pathogen] It is caused by virus particle infection of herpes virus.

【 Symptoms 】 At the early stage of the disease, many small white spots appeared on the skin surface of the diseased fish, covered with two layers of white mucus. With the development of the disease, the number and area of these white spots gradually increase, and the epidermis of the affected area gradually thickens, sometimes reaching 1 ~ 5 mm, forming paraffin-like "growth", and the surface tissue changes from soft to cartilage connective tissue. When these "growths" grow to a certain extent, they will automatically fall off, and then new "growths" will reappear in their original positions. If these "growths" account for most of the surface area of fish, it will seriously affect the normal growth of fish, make fish thin, swim slowly and even die. If there is not much "growth", it will have little impact on fish; In general, the case occurred in spring when the water temperature was about 65438 05℃. Because the disease is not widely spread, rarely occurs and has little harm, it has not attracted attention.

【 Prevention 】 This disease can be treated with levochloramphenicol. Small fish can be soaked in 0.225 parts per million (0.225 ppm) medicine, and big fish can be injected with this medicine, which can achieve certain curative effect.

Other methods:

1. Strengthen cultivation in autumn, so that goldfish, red carp and koi fish have certain fatness before overwintering, and enhance their resistance to low temperature and diseases.

2. Feed fresh animal food such as Daphnia, earthworm, chironomid larva (blood worm) regularly to strengthen nutrition and enhance the disease resistance to acne.

3. Immersion in erythromycin 10ppm concentration for 50-60min is effective for prevention and early treatment.

4. Spraying erythromycin with the concentration of 0.4 ppm ~ 1.0 ppm in the whole pool, and then smearing it after 10, has certain curative effect.

5. After erythromycin 10ppm soaking, the whole pool was sprayed with 0.5ppm- 1.0ppm, and the whole pool was sprayed with the same concentration after 10, which had certain curative effect.

Third, diseases caused by bacteria.

Common diseases caused by bacteria are as follows: 1. Bacterial gill rot.

【 Etiology 】 First, it is caused by protozoa, monoculture animals and crustaceans. The second is caused by aquatic algae, such as gill mold; The third is caused by bacteria.

[Pathogen] Myxococcus Fisch.

【 Symptoms 】 The gills of diseased fish are often filled with mucus, and there is bleeding on the inner epidermis of gill filaments and operculum. Gill silk turns from red to white, gradually decays with the sludge, and finally develops into a full gill, making it lose its respiratory function and die.

[Treatment] Ill fish can be soaked in 2ppm furacilin, 12.5 ppm chlortetracycline, 25ppm oxytetracycline and 25ppm furazolidone for 30 minutes. Or use 0.02g chloramphenicol with the concentration of 1 1.5% to dissolve in 10kg water and soak fish15 ~ 20min; Or disinfect with one millionth (1ppm) of nitrofurazone, one millionth (1ppm) of bleaching powder or two to four millionths (2-4ppm) of gallnut; Fish containers and all utensils should be disinfected with 8ppm bleach.

2. Bacterial enteritis

【 Etiology 】 The main causes are eating unclean food or overeating, intestinal fullness, obstruction of excretion, and finally enteritis caused by intestinal bacterial infection.

[Pathogen] Aeromonas punctata.

【 Symptoms 】 Sick fish often have abdominal swelling, erythema, protruding anus, dull fish body, stopping in the corner of the fish tank, muscle twitching for a short time, not eating, and white feces. When you cut open the fish belly, you can see that there is water in the abdominal cavity and the intestinal wall is congested and inflamed. In light cases, only part of the intestine appears red, while in heavy cases, the whole intestine appears purple, and there is no food in the intestine, which is full of yellowish mucus and blood pus.

[Treatment] There are many treatments for enteritis. There are many drugs on the market, such as Naco, Yufukang and sulfaguanidine. And topical drugs such as turmeric, furacilin, gentamicin, oxytetracycline, furazolidone, etc. After dilution, it can be sprinkled or soaked in the bath, which can achieve good curative effect.

3. White skin disease-also known as white tail disease

【 Etiology 】 Because the water quality is unclean, especially the excrement in the aquarium is not removed in time, or the operation is careless in fishing, transportation, stocking and moving the box, the fish body is injured, which leads to pathogen infection.

[Pathogen] is a gram-negative bacterium called Trichomonas albicans.

【 Symptoms 】 At the initial stage of the disease, only a small white spot appeared at the base of dorsal fin or caudal stalk, and then it quickly expanded and spread backward from the dorsal fin of fish, making the body surface between dorsal fin and gluteal fin white. With the aggravation of the disease, the swimming ability of the sick fish was obviously weakened, and the balance between the body and the body was out of control. The head was up, the tail fin was up, swimming up and down perpendicular to the water surface and struggling, and soon died. The epidemic season of the disease is May-August every year, and the fish die within 2-3 days after the onset, and the mortality rate is extremely high.

[Treatment] It can be soaked in 12.5 ppm (12.5ppm) chlortetracycline or 25ppm oxytetracycline for 30 minutes. You can also use one millionth (1ppm) of bleaching powder or two to four millionths (2 ~ 4ppm) of gallnut to splash it in the aquarium for disinfection. 4. White head and mouth disease

[Pathogen] is a kind of myxococcus, which is very similar to the pathogenic cocci of gill rot mentioned above. The strain grows aerobically, the optimum temperature is 25℃, the optimum pH is about 7.2, and it can grow at pH 6.0 ~ 8.5.

【 Symptoms 】 At the onset, the cells around the forehead and mouth of the diseased fish died, the pigment disappeared and turned white, and the diseased part festered, sometimes with gray villi, resulting in the symptoms of "white head and white mouth". The symptoms of sick fish swimming on the water surface are particularly obvious. When the sick fish leaves the water, the symptoms are not obvious. Severely sick fish, the diseased parts fester, and some sick fish have hyperemia in the head, sometimes showing pathological reactions such as white skin, white tail, rotten tail, rotten cheeks or whole body mucus. Sick fish are generally thin and black, breathing faster, losing appetite, swimming slowly, constantly surfacing and dying soon. The disease is an explosive disease, with rapid onset and infection, and all of them can die within one day. The epidemic season of the disease is obvious, generally from late May to early July, with the peak in June.

【 Prevention and control method 】 During prevention and control, the fish tank can be disinfected by spraying one millionth (1ppm) bleaching powder, or spraying 0.5 ~ 0.7 millionth (0.5 ~ 0.7 ppm) Heineken (containing 2.5% ethyl chloride), with good effect.

5. Hemorrhagic decay-also known as erythroderma and erythroderma. [Pathogen] Trichomonas fluorescens is a gram-negative bacterium.

【 Symptoms 】 Local or most of the body surface is bleeding and inflamed, and scales fall off, especially on both sides and abdomen of the fish. The dorsal fin or the base of all fins is congested, and the ends of the fins rot, often in one section, and the tissues between the fins are also destroyed, showing a tattered paper fan shape (also known as eating fins); The maxilla, mandible and branchial lid of the diseased fish are sometimes partially congested, and now it is a large area of erythema, sometimes congested and inflamed. Water mold often grows where scales fall off and fins rot. The disease is prevalent in a wide area, which can be seen all year round, and is often complicated with gill rot and bleeding. When a fish is injured, pathogenic bacteria take the opportunity to invade the fish, and it is easy to get this disease. When the water temperature is extremely low in winter, fish skin will also be frostbitten.

[Treatment] We can use 1% salt solution, or five parts per million (5ppm) of furazolidone, or two parts per million (2ppm) of potassium permanganate, or two parts per million (2ppm) of bleach. 6. Vertical scale disease-also known as vertical scale disease, pine scale disease, pine skin disease, etc.

[Pathogen] is a bacterium similar to Trichomonas hydrophila.

【 Symptoms 】 The symptoms of diseased fish are rough body surface, and the scales at the tail mostly spread outward like pinecones, while the scales at the base of the scales swell and accumulate translucent or bloody secretions inside, which makes the scales stand up. When a little pressure is applied to the scales, the liquid is ejected from the scales, and the scales fall off, sometimes accompanied by symptoms such as congestion at the base of the fins and the surface of the skin, exophthalmos, and abdominal swelling. The sick fish swam slowly, had difficulty breathing, rolled over, and the abdomen was upward, and died 2-3 days later. It is easy to suffer from this disease when the water quality is unclean, the light is insufficient, the water lacks oxygen, the feeding water temperature is too high, and the scales of fish are scratched. Goldfish and koi fish often get this disease, which is popular every spring. Among tropical ornamental fish, foam spawning fish such as Percidae, Bettidae and psyllidae often suffer from this disease. This disease is difficult to cure, and even after it is cured, its color and posture are not as good as before.

[Treatment] The sick fish can be soaked in tetracycline solution with the concentration of 1 unit 50,000 for bathing 1 hour; You can also use 2% sodium chloride solution and 3% sodium bicarbonate solution to mix and bathe 10 minute; Or soaked in chloramphenicol solution, furacilin powder plus furazolidone solution, or gentamicin solution, or diluted with 1% of the above liquid medicine into low-dose spray, which can be effective for several days. 7. furuncle

[Pathogen] The pathogen is Aeromonas punctata, a gram-negative bacterium. The thallus is short rod-shaped, with round ends, and the size is (0.5 ~ 0.6) μ m× (1.0 ~1.4) μ m, with 1 ~ 2 connected, extremely single flagella, no envelope and no spores. Agar colony is round, 2 ~ 3 mm in diameter, gray and translucent, and the optimum culture temperature is 25 ~ 30℃.

【 Epidemic and Harm 】 Because the focus is on both sides of the dorsal fin base of fish, and the furuncle is only in a small area of the skin, the focus protrudes outward to form furuncle, so it is not easy to form an epidemic. So there is no obvious popular season, and it happens all year round. It mainly harms carp, grass, herring and other fish.

【 Symptoms 】 This disease is also called neoplastic dysentery, and the focus is uncertain. Usually, there are 1 or several red and swollen lumps in the subcutaneous muscle tissue on both sides of the base of fish dorsal fin, which look like abscess and feel soft and swollen by hand. With the development of the disease, muscle tissue appears bleeding, body fluid exudation, and then necrosis and ulcer. Because the affected parts are on both sides of the dorsal fin base, the fin base of the diseased fish is congested and the fin is scattered. When the condition is serious, there will also be symptoms of congestion and inflammation in the intestine.

Diagnosis can generally be made according to symptoms. When the boils are not festering, the boils are cut, and muscle ulcers and pus are obviously visible. During smear examination, a large number of bacteria and white blood cells can be seen under the microscope.

[Control Method]

(1) prevention

(1) Don't hurt fish during fishing, transportation and stocking.

(2) Drug disinfection: Bathing the fish with 2 g/m3 furazolidone for 30 minutes can disinfect the injured part and prevent bacterial infection. (2) Treatment (oral and external use)

(1) oral sulfonamides, feeding together for 5 days;

② Oral furazolidone, 65438 0 times a day, mixed feeding for 20 days.

③ Oral antibiotics 10 day; Chloramphenicol 5 ~ 10 day; Tetracycline 10 day.

④ Take norfloxacin orally and mix it with feed, once a day, for three consecutive days, for 1 course of treatment. (1) To prevent the disease, the water body should be kept clean to prevent fish trauma.

② When the abscess is mature, it can be discharged surgically, then washed with nitrofurazone water and coated with nitrofurazone dry powder or antibiotic powder, which can achieve good results. Serious ones will be eliminated immediately, and those with blisters will be fished out and treated separately.

③ Large fish can be injected with 40,000 to 80,000 units of penicillin intramuscularly or washed with liquid medicine.

8. Printing disease-also known as rot.

[Pathogen] is a punctate subspecies of Aeromonas punctata, belonging to Gram-negative bacteria.

【 Symptoms 】 Ill fish are usually inflamed near the anus or at the tail stalk (rarely at the front of the body), and erythema appears on the skin and muscles, sometimes like pustules. With the development of the disease, the scales in this part fall off, and the muscles gradually rot, forming a round or oval focus, full of blood, and the edge is red, which seems to have a red mark, so it is called India disease. Sick fish are thin and swim slowly; When the illness is serious, death may occur one after another. When the water quality is unclean or the fish is damaged, it is often infected with this disease. There is no obvious popular season.

[Treatment] Fish diseases caused by Gram-negative bacilli can refer to other treatment methods. 9. Explosive hemorrhagic disease (bacterial septicemia)

[Pathogen]: At present, through preliminary identification, the pathogen * * * can be divided into three types, (1) Yersinia Luke. (2) Aeromonas. (3) Vibrio. Yersinia Luke is a pathogen suitable for growth below 20℃. The best time for this kind of bacteria to appear is March-April every year. This bacterium is the main pathogen of the outbreak during this period. Aeromonas and Vibrio are warm-water bacteria. The suitable growth temperature is between 20- 30℃. So from the end of May to the whole hot season). This kind of bacteria can be found when examining sick fish. Because the pathogen of the disease produces toxins, it causes hemolysis, bleeding and serious tissue damage of sick fish. Liver dysfunction, renal dysfunction, pancreatic dysfunction, uremia and hepatic coma in dying fish. When the water temperature is high, pathogenic bacteria multiply quickly. The disease is septicemia caused by various bacterial infections, so it is also called freshwater fish bacterial septicemia, or bacterial septicemia for short.

【 Symptoms and Diagnosis 】: At the early stage of the disease, from the appearance, the mouth, abdomen, gill cover, orbit, fins and both sides of the diseased fish showed mild congestion symptoms. When the abdominal cavity was cut open, a small amount of food was still found in the intestine. With the development of the disease, the above-mentioned body surface congestion intensifies, muscles appear bleeding symptoms, congestion around the orbit, exophthalmos, abdominal swelling and redness. Open the abdominal cavity, it is obvious that the internal organs (liver, spleen, kidney, etc. ) damage, resulting in yellow or red ascites in abdominal cavity, hepatosplenomegaly, congestion of intestinal wall, flatulence and no food. Gray gills show anemia, sometimes purple and swollen, and in severe cases, the ends of gill filaments rot. From March to April, the symptoms of inflammation and congestion on the body surface of sick fish are: head, mouth, gill cover, eye socket and other parts on both sides of the body surface, especially under the ventral fin and tail stalk. Some diseased fish can see exophthalmos, branchial anemia, inflammation of internal organs in different degrees, and sometimes intestinal swelling. After 5 months, the symptoms of diseased fish are mostly congestion and inflammation in the lower edge of gill cover, fin base and viscera, and sometimes congestion and inflammation in the mouth and muscles at the same time. At this stage, the clinical symptoms of sick fish are more complicated, and sometimes the fish dies when the physical symptoms are not obvious. At the same time, the symptoms of each sick fish are not exactly the same, so it is difficult to have an absolute boundary.

[treatment method]

1, clean the fish tank thoroughly.

2, medication:

Dactylogyrus (freshwater fish)

Treatment: Kill the fish ectoparasites on the first day.

Disinfection: Choose one of the following fish medicines.

Calcium lime, Youchlorine, trichloroisocyanuric acid and chlorine dioxide preparations (Baiduqing, Miduwang, Yuxian, etc. ) should be applied and disinfected according to the instructions.

Fourth, diseases caused by fungi.

1. Dermatomycosis, also known as water mold and white disease, is one of the most common diseases of ornamental fish.

[Pathogen] It belongs to Hymenoptera, Hymenoptera, Heterobacteria, Myxomycetes, Pythium, etc.

【 Symptoms 】 When fishing and transporting ornamental fish, the skin of the fish was accidentally injured, or the skin was damaged by parasites. The spores of mold invade the wound, absorb nutrients and germinate quickly. One end of the mycelium infiltrates into the muscle inward, and the other end grows outward, forming cotton-wool mycelium. When mold is only parasitic, it is not easy to be found by naked eyes; When visible to the naked eye, mycelium has invaded from the wound of fish and grown from the outside to the inside. Mycelia entangles and adheres to the wound tissue, causing tissue necrosis. Due to more and more cotton-wool hyphae, the fish body is overloaded, which makes swimming abnormal, loss of appetite and emaciation, leading to death. When ornamental fish are infected with mold, they will also be affected by the length of light. Continuous rain for a long time, or insufficient indoor lighting, sunlight and other light sources will promote the growth of mold. The skin of fish infected by mold is usually covered with a layer of white, especially black and red fish, thus losing the luster of fish. Subsequently, the activity is slow, often dull, floating on the water. If not treated in time, the mold of fish will spread, the muscles of the affected area will rot, the appetite will decrease, and eventually it will lead to death.

[Treatment] Dermatomycosis can occur all year round, especially in early spring and late winter. In order to prevent the occurrence of water mold, attention should be paid to prevent fish from being injured and bitten by parasites, and a small amount of salt can be put in the water to inhibit the occurrence of water mold. When fish are found to be infected with water mold, they can be soaked in 3% salt solution for 5-1 0 minutes every day, or in 2ppm potassium permanganate solution and 1% salt for 20-30 minutes, or in 1-2 ppm malachite green solution. Or soak in 1-2 ppm (1-2 ppm) methylene blue solution for 20-30 minutes, or soak in 5ppm (furacilin solution), or directly sprinkle 0.02ppm (malachite green solution) and 0.3ppm (formaldehyde solution) into the aquarium for inhibition. You can also raise the water temperature to inhibit the growth of water mold. Installing a 15W ultraviolet lamp on the top of the aquarium for several hours every day can effectively inhibit or eliminate the breeding of water mold.

2. gill mold

[Pathogen] Belongs to Cladosporium.

【 Symptoms 】 When spores are scattered in water, they contact gills, then stick to gills, invade their tissues to grow, develop into hyphae, and keep branching, and pass through gills like earthworms, destroying tissues and turning normal bright red gills into pink, showing a serious anemia state. With the development of the disease, the respiratory function is seriously hindered, and even the sick fish die. The course of disease is often acute. At the onset, a few fish died, but on the second to third day, a large number of fish died suddenly. When the water quality is unclean and deteriorated due to too much organic matter, it is most suitable for the mass reproduction of gill mold.

[Treatment] There is no good treatment for gill mold, which mainly depends on paying attention to prevention, keeping the water clean and pre-disinfecting it. The treatment method can refer to the treatment method of dermatomycosis.