CATDOLL : CATDOLL: What medicine should be prepared for raising eels?

1Prevention and treatment of ecological diseases

Fever

Fever disease mainly occurs during transportation, mainly because during transportation, the density is too high, the eels secrete too much mucus, accumulate and ferment, and the dissolved oxygen decreases. The symptoms of this disease are: the eels are entangled with each other, and a large amount of mucus on the body surface falls off. In terms of prevention, the shipping density should be strictly controlled; loaches should be transported in a tethered manner, and the loaches' characteristics of swimming up and down should be used to prevent the eels from entangled with each other; ginger slices should be added to the transport box, 100g per box, and new water should be replaced in time.

Madness

Madness usually occurs in early summer and late spring, mainly after the eel fry is put into the box. Due to sudden changes in weather and environment, the stress response is strong, which reduces the physical fitness of the eel fry, causes physiological metabolism disorders, affects mucus secretion, and makes the skin of the eel fry lose resistance, leading to virus invasion and infection. The sick eel has no appetite, often swims fast like an arrow in the box or entangled on water plants, similar to madness; it has difficulty breathing, sticks its head out of the water, and opens its mouth; the body rotates and struggles in an "S" and "O" shape, and the muscles of the whole body show spasms and tremors; when you touch its body with your hands, you will feel stiffness, there is no obvious trauma or ulceration on the body surface, and there is little mucus or no sticky mucus falling off. In terms of prevention, during transportation, keep the water temperature stable and the water environment excellent to minimize the stress caused by environmental changes; in order to enhance the physical fitness of the eel, vitamin C, multivitamins, etc. can be mixed into the feed to reduce the stress response. For treatment, you can spray Sujian V9 0.3 g/m³ of water in the whole pond inside and outside the cage; then spray Plant Anti-Toxic C 10 mL/box in the diseased cage.

Bleeding disorders

Hemorrhagic disease is prone to occur in the early stage of seedling release or before adult eels enter winter. It is a syndrome caused by poor seedling quality or weather factors such as continuous low temperature, rainfall and other adverse environments, which reduce the resistance of eels and cause cross-infection of bacteria and viruses. Sick eels will partially expose their bodies above the water at night and their heads above the water during the day. The body surface is covered with blood spots, and the shapes of the blood spots vary. Occasionally, there are diffuse bleeding symptoms all over the body, the most obvious part is the abdomen; the anus is red and swollen, and there is bloody mucus in the mouth and gills. The liver is enlarged, dark brown, and inelastic when dissected, and the abdominal cavity and intestines are congested. For prevention, the eel body can be soaked in 10 g/m³ of povidone iodine water. For treatment, first disinfect the whole box, glutaraldehyde can be used, and on the second day, spray povidone iodine 1 g/m³ water body on the whole box; take oral medications, such as hemostatic drugs, antiviral drugs, allicin, etc., for 7 consecutive days; spray the whole box with 1 mg/L of Jundujing, and add 3 g/kg of Sanhuang powder and 5 g/kg of eel Kangbao to the feed for feeding.

White dew disease

Causes of the White Dew Syndrome in Rice Field Eels: Every September, some farmers have to sell their eels at low prices due to a large number of diseases. Since the disease is mostly concentrated after the "White Dew", many farmers are accustomed to calling it "White Dew Syndrome". In fact, "White Dew Syndrome" is mainly caused by liver lesions (swelling, whitening, and brittleness), so strictly speaking it is a liver disease. The main reason for the "White Dew Syndrome" in rice field eels is that they are fed a large amount of feed with a high protein content, which overloads the eel's liver and causes the disease.

The main methods of preventing eel white dew disease are:

(1) Do a good job of feeding training. Some farmers do not do a good job of feeding training. Often, only a portion of the eels in the farm will eat. On the surface, the eels' food intake is relatively normal. In fact, the eels that eat frequently are often eating too much. The size difference of eels in the same box is very obvious. Large eels often die from liver diseases after long-term excessive intake of high-protein feed. This is why farmers often find that some cages or eel ponds are the only place where large eels die. When farmers are training eels to eat, for cages or eel ponds that eat slowly after feeding and have fewer eels coming out to eat, fresh feed should be used for individual training until the amount of fresh feed consumed by the eels reaches more than 4% of their body weight, and then compound feed should be gradually added for conversion.

(2) Properly control feeding. When the eel's feed intake exceeds 8% of the weight of the seedlings, it is best to stop feeding for one day every five days to relieve the eel's liver load. At the same time, add "Eel Treasure Liver Protection Ning" to the feed once every 15 days (3 to 5 grams of medicine per kilogram of feed). After entering autumn, farmers with conditions can appropriately increase the proportion of fresh feed.

(3) Choose feed with high fat content In some areas where fresh feed is scarce, it is best to choose feed with slightly lower protein content but higher fat content to feed eels. This can effectively reduce the possibility of eels suffering from "white dew syndrome". Feed with a crude protein content of more than 36% and a crude fat content of more than 6% is ideal.

2 Bacterial diseases

Skin rot

Skin rot often occurs in summer and autumn. It is mainly caused by factors such as high stocking density, inconsistent seedling specifications, improper box division, and problems with cage soaking, which cause eels to be injured and infected with bacteria. The surface of the diseased eel has round and oval red spots as big as soybeans, which are congested and inflamed in spots. The most obvious parts are the two sides of the abdomen; the head of the diseased eel often sticks out of the water and swims weakly; in severe cases, its epidermis rots, ulcers appear, and severe bones and internal organs are exposed. Occasionally, congestion and inflammation of the intestines and anus can be seen. In terms of prevention, try to avoid eels from being damaged; after the beginning of autumn, control the area of ​​aquatic plants and keep 15% of the empty water surface in the cage; before the White Dew and the Cold Dew, sprinkle the cage with 30 g/m³ of quicklime for 3 to 5 consecutive days. In terms of treatment, 1 to 2 g/m³ of povidone iodine can be used for disinfection; remove the head of the toad and drag it in the pond.

Red skin disease

Red skin disease is most common in late spring and early summer. Most cases are caused by trauma caused by fishing or transportation, which allows bacteria to invade the skin. The diseased eels have local bleeding and inflammation symptoms on the surface of the body, and the scales fall off, especially on the abdomen and sides, which are more serious and fall off in blocks. For prevention, bleaching powder 1 g/m³ water can be used and evenly sprinkled throughout the pond. For treatment, the diseased eels can be immersed in 2.5% salt water for 15~20 minutes; or the affected area can be scrubbed with 2.5%~10.0% salt water.

Bacterial enteritis

Bacterial enteritis is most prevalent in summer, mainly caused by eels eating rotten and spoiled bait or uneven hunger and satiety, which causes parasites in the intestines. Sick eels move slowly, have no appetite, have black body surfaces, especially the head, have red spots on the abdomen, and have red and swollen anus. Yellow or red mucus will flow out when the abdomen and anus are pressed lightly. There is no food in the intestines, and some or all of them are congested and inflamed. In terms of prevention, add a little garlic extract when feeding, do not feed rotten and spoiled bait, remove residual bait in time to prevent water quality deterioration; use 30 g/m³ of quicklime to clean and disinfect the pond. In terms of treatment, the principle is to combine oral and topical drugs. For every 5 kg of eel, 5 g of sulfathiazole or 1 g of furazolidone is mixed with bait and fed for 3 to 5 days; for every 5 kg of eel, 3 to 5 g of allicin is mixed with bait and fed for 3 days every 5 to 7 days; for every 10 kg of eel, 500 g of decoction of Herba Lycopodii, Polygonum hydropiper or Acorus calamus is mixed with feed and fed for 3 days; for topical drugs, 10 g/m³ of quicklime, 1 to 2 g/m³ of bleaching powder, or 2 to 3 g/m³ of erythromycin solution for poultry is usually used to soak the eel for 10 to 15 minutes.

Tail rot

Tail rot is more likely to occur in high-density breeding ponds and during transportation. It is a common disease of eels and is not easy to prevent and treat. It is a disease caused by a bacterium in Aeromonas. The tail of the diseased eel is congested and inflamed, and then the muscles are necrotic and ulcerated. In severe cases, the tail stalk or tail muscles rot, and only the tail vertebrae are exposed. For prevention, the water quality and environmental sanitation management of the eel pond should be strengthened to avoid the massive reproduction of bacteria. For treatment, povidone iodine 1~2 g/m³ water can be used for disinfection; furazolidone 0.24 g/m³ water can be used for spraying throughout the pond; chlortetracycline 0.25 U/mL can be used for immersion and disinfection of sick eels; toads can be decapitated and dragged in the pond.

3 Fungal diseases

Common fungal diseases are mainly Saprolegniasis, which is most prevalent in late spring and early winter. The disease is mainly caused by eels biting each other, mechanical damage or invasion of harmful organisms, and the wounds are infected by Saprolegnia. There are no obvious symptoms in the early stage of the disease. After a few days, cotton-like hyphae grow outward from the affected area and quickly spread on the body surface, becoming "white hair" visible to the naked eye, and muscle erosion; sick eels leave their holes and swim alone, have no appetite, and finally become emaciated and die. For prevention, quicklime can be used for disinfection, and care should be taken to avoid injury to the eel during operation. For treatment, 5% iodine or 1% malachite green ointment can be applied to the affected area; soak the sick eels in 2%~3% saline for 3~4 minutes, and soak them continuously for 2~3 days; replace new water, and sprinkle 0.04% soda water and 0.04% saline throughout the pond.

4 Parasitic diseases

Acanthocephalus

Acanthocephalus disease is mainly caused by the head of the acanthocephalus drilling into the intestinal mucosa of the eel, destroying the tissue, often wrapped in the chest wall mucosa to form a cyst, allowing other pathogenic bacteria in the intestine to enter the intestinal wall and cause inflammation. The sick eel has almost no appetite, the body color turns blue and black, and the anus is red and swollen. After dissection, white stripe worms can be seen in the intestine, with a body length of 8.4~28.0 mm, which can shrink and the snout firmly drills into the intestinal mucosa, causing intestinal congestion and inflammation, and in severe cases, intestinal perforation. For prevention, 90% crystal trichlorfon 0.05 g/m³ water body can be used and sprayed throughout the pond. For treatment, use 0.2~0.3 g of tobendazole and levamisole for every 100 kg of eel, mix with bait and feed, and feed again in the same way after 2 days; use 40~45 g of 90% crystal trichlorfon mixed with feed for every 50 kg of eel and feed for 6 consecutive days.

Capillariasis

Capillariasis is mainly caused by the head of the capillaries drilling into the mucosal layer of the intestinal wall, destroying the tissue, allowing other pathogens in the intestine to invade the intestinal wall, causing tissue inflammation and ulceration. The abdomen of the diseased eel is upward, the head is out of the water, the body color is black, and the anus is red and swollen; after dissection, milky white, thread-like, 2-11 mm long capillaries can be seen in the hind intestine. For prevention, 90% crystal trichlorfon 0.05 g/m³ water body can be used and sprayed throughout the pond. For treatment, veterinary trichlorfon tablets (0.5 g/tablet) can be soaked in water, then crushed, mixed with feed at 0.1% and fed for 6 consecutive days; 90% crystal trichlorfon 5.0-7.5 g per 50 kg eel is mixed with feed and fed for 6 consecutive days.