1. There are two main sources to choose the artificially cultured Monopterus albus fry, namely, artificial propagation and wild collection. Regardless of the source, you should distinguish the types before selecting fry.
1. 1 difference type: the type difference of Monopterus albus seedlings mainly depends on the body color spots. High-quality seedlings are yellow or slightly golden yellow with a large area of dark brown spots inside. The growth speed is fast, the weight gain multiple can reach 5-6 times, and the yield and benefit are high; Middle-fingered eel is bluish yellow, with small variegated color, average growth speed and weight gain of 3-4 times, which is suitable for general large-scale culture. Inferior fry, the eel body is gray or bluish gray, the mottled color is not obvious, the growth rate is slow, the weight gain is only 1 ~ 2 times, the yield and benefit are low, and it is not suitable for artificial breeding.
1.2 Distinguishing between good and bad: There are two ways to distinguish between good and bad Monopterus albus seedlings: one is to look at the capture method; All seedlings caught in cages and nets can be purchased; No hook fishing, electric fishing or poisonous seedlings can be collected. Second, watch activities with water; Swimming freely, bright body surface, no red blood spots, moderate mucus, strong hand grip, healthy seedlings; Otherwise, swimming is slow, the body is sluggish, there are red blood spots, mucus falls off, hands are weak, and most of them are weak or sick eels.
2. Disinfection of the eel pond: clean the pond body for disinfection before stocking the fry, and use quicklime 180 ~ 225 g per cubic meter of water, and fry can be put in after 7 ~ 8 days; Disinfect the seedlings before stocking, soak them in 3% ~ 4% salt water for 5 ~ 10 minutes (low temperature time is longer, high temperature time is shorter), then rinse them with clear water and then breed in the pond.
3. Water quality Monopterus albus likes to live in relatively clean water with a pH of 7.6 ~ 8.5. There should be a certain silt layer at the bottom of the pool, preferably still water or micro-flowing water. Plant some aquatic plants in the pond properly, and change the water 1 time every 3 ~ 5 days, every 2 days in summer high temperature, and every time 1/3 ~. The micro-flow water does not need to be changed, the flow rate is controlled within 0.2m/ s, and the temperature difference between the inlet water and the pool water does not exceed 3℃. Monopterus albus has strict requirements on water quality and is not suitable for breeding in acidic soil, rich water or places with corrupt water quality. Monopterus albus is not easy to get sick in natural waters. If the water quality is sour and fat, it is easy to induce diseases and even a large number of deaths.
4. The selectivity of feeding Monopterus albus is strict, and it is difficult to change a bait once it has been fed for a long time. Therefore, in the early stage of feeding, it is necessary to do a good job of taming food in a short time. The first domestication 1 time is to feed mixed bait, in which earthworms, fly maggots, wheat bran, rice and vegetable leftovers are added. On the third day after the larvae entered the pond, they began to tame the food. The feeding amount on the first 1 day is 1% ~ 2% of the stocking weight, and it is increased or decreased according to the feeding situation on the second to third day. For normal feeding, increase 1% every day until the mixed bait completely replaces the original bait and reaches normal feeding. (1 Domestication is the transitional bait at seedling stage). The second domestication, that is, feeding artificial compound bait or granular bait. Feed 20% on 1 day. If the feeding is normal, increase the feeding amount by 20% every day. After 5 days, it can completely replace the original bait. The second taming is a broad-spectrum bait for larvae and adults.
5. Disease Prevention The common diseases of Monopterus albus in the process of artificial high-density intensive farming are:
5. 1 Symptoms of enteritis: mainly depends on the color of the anus, and the gray anus is normal; The anus is red, congested, purplish red and everted, which is a sick eel; Sometimes gill bleeding, lifting the bleeding water from the tail and mouth, shows refusal to eat, which belongs to bacterial infection, with short course of disease and high mortality. Prevention and control: ① Sprinkle quicklime 20 ~ 25g per cubic meter of water in the whole pond, 65,438+0 times a day for 7 days; ② Oral administration of 10 drops of water (20ml), thiamine guanidine 10g or furacilin 20g; Monopterus albus fed with 20g chloramphenicol every 100kg for 3 days.
5.2 Hemorrhage symptoms: punctate, massive or diffuse congestion on the body surface, obvious in abdomen and throat, sometimes oral bleeding, gill rot, acute onset and high mortality. Prevention and control: ① improve water quality and environmental sanitation conditions; ② Use 0.2 ~ 0.25g of furazolidone per cubic meter of water, and sprinkle it all over the pool; ③ Soak eels with 0.25 units of chlortetracycline per milliliter. 5.3 Symptoms of Hydromycosis: The silk of Hydromycosis is mainly parasitic on the wound on the body surface of Monopterus albus, spreading in the form of white floc, and the pathogen is mostly fungal cotton mold. Control: Use 0.2g malachite green or 3g methyl blue or a mixture of 0.05% salt and 0.05% baking soda per cubic meter, 1 time, every 3 days 1 time, for 3 times in a row.
5.4 Symptoms of capillary nematodiasis: This worm is mainly parasitic in the middle and rear parts of the intestine, and its body is milky white, and the sick eel is gradually wasting away. Control: 1kg Monopterus albus oral administration of 90% crystal trichlorfon 0.04 ~ 0.1g; Or 1kg earthworm is mixed with 2.5g of 90% crystalline trichlorfon for 3 days, and 0.2g of 90% crystalline trichlorfon is sprayed per cubic meter of water the next day.
5.5 Fever symptoms: At high density, eels secrete mucus at a high speed, and the waste mucus cannot be removed in time, and the fermentation releases high fever, which leads to a sudden increase in water temperature, which makes the eel's body temperature rise, and sick eels come out of the hole, intertwine with each other, and the mucus falls off, resulting in a large number of deaths. Prevention and control: ① Replace with fresh water; ② 5g of 0.07% copper sulfate aqueous solution is used for every cubic meter of water, and the whole pool is splashed; (3) Add a small amount of loach to increase the cleaning capacity of running water.
6. Precautions:
6. 1. The cultured Monopterus albus has high technology content and strict requirements on water quality; Therefore, all localities should adapt to local conditions and not blindly develop.
6.2. Artificial culture of Monopterus albus should be adapted to local conditions. Where conditions permit, the scientific and technological strength is sufficient, and large-scale mass production can be carried out; It is advisable for rural specialized households to adopt small-scale rolling development or temporary feeding and fattening, and its economic benefits are also very good.
6.3. The artificial culture of Monopterus albus is managed by ecological principles, in which special attention should be paid to planting some aquatic plants with strong pollution absorption ability, such as water peanuts and water hyacinths, so that Monopterus albus can live in seclusion, prevent heatstroke and cool down, improve water quality and purify water quality.
6.4. Attention must be paid to the prevention and control of diseases in cultured Monopterus albus. ① Lysozyme decreased. Lysozyme in the mucus of Monopterus albus has strong bactericidal ability. However, in artificial scale culture, due to transportation injury, high density, deterioration of water quality, changeable water temperature and other factors, lysozyme is reduced, its activity is reduced, and bacteria invade and cause disease. ② The disease was found late. Monopterus albus likes to live in mud, and it is not easy to find out when it begins to get sick. Once found, the disease has spread and the best treatment period has passed. ③ Taste allergy. Huang Xian is sensitive to taste and refuses to swallow tasteless, bitter and exciting bait; So the drug treatment effect is not obvious.
6.5. Monopterus albus cultured artificially should be neat in specifications and separate in size. Generally, 20 eels per kilogram are suitable (because each 50g fry has high survival rate, fast weight gain and high yield), and the stocking density is per square meter1~ 2kg.
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