Interpretation of Blackfish Culture Science
In today's aquaculture industry, Black Stork (Blackfish) has become the breeding target of more and more farmers. However, the phenomenon of restricting unit production, threatening product quality, affecting sustainable development, and causing the outbreak of diseases still exist. To solve this series of issues, the key is science and technology, technology, management, and philosophy. As the core content of "agricultural science and technology" mentioned in the "Central Document No. 1" in 2012, again, only science and technology can make you Go farther in this aquatic product!
"Establishment of an agricultural extension system" is another key word in this year's "Central Document No. 1". Therefore, with some operations in the process of artificial intensive culture of Ukrainian artemisia, the author communicated with everyone in a scientific and easy-to-understand way. I hope this expression and content of this article will benefit more aquaculture farmers. At the same time, it is explained that the points mentioned in this article are only the main points in the process of aquaculture. The content may not be comprehensive enough.
First, prepare before feeding
1 The selection of ponds and water depths shows that after many years of breeding experience, the area of ​​aquaculture ponds is generally 1-3 mu, which is too inconvenient for management. The best water depth is 1.5-1.8m, the water is too shallow, the water capacity is small, the water is too deep, and the water temperature at the bottom of the water body should not rise.
2 Disinfect the ponds and fish bodies. The ponds should be sterilized by dry ponds within half a month prior to stocking fry, and use 100-150 kilograms of quick lime per acre. And to kill or catch the old black dragonfly to prevent damage to the seedlings. Before the fry is released, the body surface may be injured and there is a bacterial infection, so it is also necessary to disinfect the pond. That is, the fish body can be infiltrated with 3%-5% saline for 10-15min, and 15g/m potassium permanganate can also be used. Soak the solution for about 10 minutes.
3 If the fry is to be selected and released, if it is stocked with fry every other year, it may be stocked in 110-150g, fry with a length of 16-20cm and stocked 30005000 fish in March-April. If the stocking specifications are basically the same, there is no need to screen the stock after Xia Tang. After 6-8 months of cultivation, the stock can be listed in the same year. If fry is stocked in the year, stocks of 30-50g can be stocked in June-July, and fry 3-5cm in length can be stocked with 50007000 fish. However, it takes 2-3 times of breeding to avoid mutual killing.
4 Anti-escape and infrastructure, Ukrainian dragons are good at jumping and hidding against the currents. Therefore, there must be measures to prevent the escape of ponds and drains. Fences or nets should be set around the ponds, and other equipment such as pumps and aerators are also required.
Second, feeding and precautions
Umbilicus is a carnivorous fish. At present, people commonly use small trash fish, shrimp, chilled fish, livestock and poultry as waste materials. According to statistics, the net increase in the weight of 500g fish is 2.2 to 2.7kg. fish. There are the following points regarding the feeding:
1 Adopt the conventional “Four Principles†(timing, fixed-point, qualitative, quantitative), and each feeding adopts a “less, more, and less†feeding method. Its role is to induce fish to eat and form food-grabbing scenes. Unsatisfied black quail continues to eat, which is beneficial to reduce the waste of bait and promote the uniform growth of black locust.
2 After April, the temperature of water continued to increase, and the food intake of black storks continued to increase. From April to mid-July, mid-September to mid-September, the temperatures were suitable. The metabolism of Chinese black buckwheat was more plentiful, and the feed amount could account for the weight of fish. 5%-7%. In mid-June-September, the temperature is relatively high, and the metabolism of Chinese wolfberry is very strong. However, 80% of it is full, and food and vomiting will occur in Safflower and Scorpio. The table below shows the feeding conditions of the researchers during the various months of feeding Ukrainian turtles:
3 For small-scale farmers, or for fish farmers who have access to fish, they can use small trash fish as feed, but for large-scale farms, it is best to use compound feed or self-mixed feed. The Chinese wolfberry self-made feed formula is generally 50% for animal food such as fish meal, blood meal, and slaughtered leftovers, plant food such as bean cake, peanut cake, wheat bran, corn flour for 45%-48%, and bone meal 2%-5%. , as well as some additives. In short, the protein content in feed should not be less than 38% and the fat content should be no less than 8%.
Third, the management of water quality
Good or bad water quality is the key to the breeding process of black razor clams. It is the basis for improving yields, preventing diseases, and ensuring quality. It should be regarded as a key management object. There are several ways to improve water quality:
1 Rational planting of aquatic plants, described below; stocking appropriate amount of earthworms, because the earthworms are all filter-feeding fish, the pond water of Wuji tends to become fat, the plankton breeding is fast, and the water can purify the water, and at the same time, it can obtain additional income. However, the stocking specifications must be large, otherwise they will be eaten by Wuhuan.
2 Regular application of quicklime, 15-20 kg of quick lime per acre per half-month. Since Ukrainus is a carnivorous fish, the excrement is acidic, and quicklime can play a role in neutralizing pH, but also has the function of sterilization.
3 Regularly sprinkling microbial preparations to accelerate the decomposition of organic matter at the bottom of the water, which can effectively prevent the breeding of bacteria at the bottom.
4 Install a mechanical oxygen system to promote the circulation of water, increase oxygen, help to decompose the reducing substances such as methane, hydrogen sulfide and ammonia at the bottom, and increase the carrying capacity of the water body.
5 Regularly infuse new water, the above four points play a certain role in purifying the water body, but still need to renew the water body, and can change the water according to the specific conditions of the water body. There is no qualitative requirement. Generally, from July to October, it will be the season for the growth of Wuhuan, and it will be changed frequently. , The general transparency is less than 25cm must change the water.
Fourth, the rational arrangement of aquatic plants
Umberella is a carnivorous fish. It has a large amount of food and excrement, and the water quality is easily deteriorated. Some farmers may overlook this point. It is generally believed that aquatic plants should account for about 20% of the total water surface. Too little purification effect is not enough. Too much (as in the right diagram) the surface of the water receives less light, which inhibits the growth of phytoplankton, reduces the oxygen production capacity of the water, and is not conducive to the water body. The temperature rises and the water body is low. Aquatic plants with well-developed root system should be selected because of their strong ability to absorb nitrogen and phosphorus in water, and they can effectively control the eutrophication of water bodies such as water peanuts, bamboo leaf vegetables and water hyacinths. It is worth mentioning that not all aquatic fish are used for the cultivation of all kinds of aquatic plants, such as filter-feeding fish (cockroaches, cockroaches) and omnivorous fish (fungus, cockroaches).
V. Comprehensive prevention of diseases
A good growth environment, timely preventive measures, and proper management methods are the main ways to prevent the outbreak of the disease. For the diseases that arise in farming, the principle of "prevention first" should be adhered to, and generally it is considered that prevention has gotten in place, and the cultivation of black crickets rarely falls ill.
1 Confirm that there is no pollution in the water source, ensure the safety and health of the pond water quality, control the amount of fish stocks, ensure that the bait is fresh and not deteriorated, and often disinfect foodstuffs, pond stems, fishing gear, and even food.
2 For water body disinfection and prevention, use 15-20 kg of lime per acre for water quality improvement and sterilization every half a month. For fish breeding stage, use 20-30 ml of avermectin per acre at a depth of 1 m. Sprinkle once every 10 days. , It can prevent and treat parasitic diseases; 0.3-0.5 kg of chlorine dioxide (or other chlorine-containing disinfection products) per acre of water at a depth of 1 meter can be sprayed once a month to prevent and treat bacterial diseases; every half a month, per kg Add 2 grams of allicin to feed and use it for 3 days to prevent visceral diseases;
Sixth, the treatment of common diseases
According to the survey of actual breeding conditions, this article will list some of the most common conditions and treatment methods in the process of artificial breeding of Chinese wolfberry. For some virus diseases, parasitic diseases, etc., there is currently no effective treatment.
1 ascites, symptoms: diseased fish scales erect, pectoral fins, anal fins were congestive edema, abdominal softness, enlargement, water filling the body; more surface mucus, some parts of congestion, whitish pale white color; hepatomegaly presented Purple, subcutaneous water, mesentery, body cavity membrane, gonads have bleeding spots. Treatment method: Inject new water and treat ascites with sputum, kanamycin, sulfamethoxazole or norfloxacin. The effect is as effective as 6 g of bait for every 100 kg of fish. At the same time, about 50kg of quicklime can be poured per acre for 3-5 days.
2 Saprolegniasis: Symptoms: Eichhornia fish body weight loss, anorexia, early: symptoms are not obvious, only some of the gray spots. Mid-term: spotted blood spots appear on the surface of the body and white areas appear. The diseased fish is free of fish and remains in the water. Late stage: Cotton-like mycelium grows in the fish body lesion area and the tissue is necrotic. It is generally caused by infection with water molds after fishing, transportation and stocking injury or poor water environment. Treatment: Sprinkle formalin at 30-50ml/m in a fish pond with watery mildew and then increase oxygen in time. 0.3-0.5 mg/L methylene blue can also be used to disinfect the whole pool for 3 to 5 days. The effect is also good. Injured fish can be infiltrated with 3% to 5% saline.
3 Hemorrhagic disease, enteritis, symptoms: The diseased fish has erythema on both sides of the body and in the abdomen, the back is dark in color, and the anus is red and swollen; the liver has blood clots or yellow petiole, intestinal congestion, and intestinal mucosa shedding and ulceration. It may be due to the feeding of deteriorated bait, higher water temperature and more water quality. Treatment method: Inject new water, and sprinkle about 50kg of quick lime per acre, and use 2mg of Dacella per 1kg of fish, and feed it with mixed bait for 3-5 days. Oxytetracycline or allicin can also be used. For example, 0.5 kg of chopped garlic seeds or 5-8 g of oxytetracycline per 100 kg of fish is used for feeding.
4 Turnip, Symptoms: White spots appear on the head and body surface of Chinese black crickets at the early stage of disease; In the middle stage, scales fall off, skin ulcers are festering, and infections are severe; In the later stages, severely, the abdominal wall rots and shows internal organs, and the head can rot. Upper and lower jaws and tails can rot the caudal fins. Treatment: 1 g/m bleaching powder or 0.3 g/m strong chlorine fines Quanchiposa, even for 3-5 days, while adding chlortetracycline in the feed.
5 Myxosporidiosis, Symptoms: The pathogenic parasites are extensive. On the surface of the black worm, the white cysts, rice grains, and bleeding at the lesion site occur. Therapeutic method: can be treated with 0.2-0.5g/m splashed crystal trichlorfon, at the same time, 90% of the crystal trichlorfon bait fed; Quanchiposa 30-50ml/m formalin, there is a certain Efficacy.
Seventh, the artificial breeding of black eagle
The breeding of black storks is actually relatively simple. The breeding season is from mid-May to mid-August each year. Artificial breeding is best done from mid-June to early July (Chen Deying, 1998). Floating eggs, eggs are yellow, with oil Balls, spawning up to several thousand to more than 10,000 tablets at a time, the breeding of blackbird have the following key points:
1 The identification of male and female, as shown in figure:
2 Oxygen production hormones and oxytocin, commonly used hormones for pueraria production are: fish ovulation hormone 3 (LRH-A3), fish ovulation hormone 2 (LRH-A2), domone maleate (DOM), fluff Membrane gonadotropin (HCG), B mixed oxytocin fish, hormone-free fish hormone, squid release hormone analogue (SGnRN-A) and so on. Oxytocin can be mixed or used alone, for example: ovulation hormone No. 3 (powdered), diluted with distilled water, at a dose of 50-60 g/kg for females, in two injections, the first being 1/3 of the total No less than 10 hours between two injections. The male fish was halved and injected with the female's second injection. The pectoral fin base was injected into the body cavity and the needle was inserted approximately 1 cm. As long as the parental pod is mature and the external environment is suitable, the oxytocin has no obvious effect on the oxytocin production (Hu Guohong et al., 2001).
3 In other spawning environments, the spawning water temperature of Wuji is 25-30°C, and the optimum water temperature is 28°C (Xu Yanshan et al., 2001). The fertilized egg hatching water temperature is 26-28°C. After about 30 h, the larvae can be hatched. Incubator pools need to maintain micro-flowing water, arrange fish nests, fresh water, rich in dissolved oxygen, and use the available chlorine 30% bleaching powder (2mg/L) or strong chlorine extract (0.3-0.5mg/L). Waterproof mildew can be used; generally use the paired spawning instead of group spawning (Guan et al., 2001), and the soon-to-be sex hormones are put into small cages or pools for fertilization and spawning, so fertilization rates and yields Egg volume is high.
Summary: This article makes a brief analysis of the artificial breeding of Chinese wolfberry, which is characterized by clear, intuitive, clear, and rigorous science. "Fish can feed, but the output is high and low; the yield is good, but the cost is many; the profits are many, but the quality is different." Therefore, I hope that this article can bring more inspiration to the black tadpoles and other aquaculture farmers. And harvest!
Takoyaki Machine,Fish Grill,Electric Fish Grill,Gas Fish Grill
Guangzhou New Power Catering Equipment Manufacturing Co.,Ltd , https://www.gznewpower.com