One, adult fish pond mixed culture
Adult fish pond mixed culture of Pelteobagrus fulvidraco, there is no strict requirement for the pond main fish. The fish ponds of the four major fish and the main feeding fish (such as carp, tilapia, freshwater white pomfret) can be mixed with Pelteobagrus fulvidraco. Fish pool area of 20 acres to 30 acres, water depth of 2 meters to 2.5 meters, adequate water supply, good water quality, convenient injection and drainage. Generally mu put Pelteobagrus fulvidraco 40 ~ 50, specifications 3 cm / tail ~ 4 cm / tail, can mu increase the income of Pelteobagrus fulvidraco 5 kg ~ 8 kg.
Second, the parent fish pool mixed culture
Parent fish pool mixed culture can not only make full use of the parent fish pool of the water body space, improve the utilization rate of the parent fish pool, and Pelteobagrus fulvidraco can ingest some of the parent fish pool with the parent fish compete for food and oxygen consumption of small wild fish. After the end of the artificial reproduction of the parent fish, each mu stocking of Pelteobagrus fulvidraco 40 ~ 60, specifications 2 cm / tail ~ 3 cm / tail, can mu increase the harvest of Pelteobagrus fulvidraco 6 kilograms ~ 10 kilograms.
Three, into the crab pool mixed culture
Crab pool mixed culture of Pelteobagrus fulvidraco, can make full use of the natural bait biological resources in the crab pool. General crab pool area of 30 mu ~ 50 mu, watercress coverage rate of about 50%, after the crab stocking, mu stocked 30 ~ 50 tail of Pelteobagrus fulvidraco, specifications 3 cm / tail ~ 5 cm / tail, can mu increase Pelteobagrus fulvidraco 5 kg ~ 10 kg.
Fourth, mixed culture in the river
River in the low value of wild fish more, mixed culture of Pelteobagrus fulvidraco can save artificial bait. Generally mu put 40 to 60 tail catfish, specifications 2 cm / tail ~ 4 cm / tail, can mu increase the yellow catfish 6 kg ~ 12 kg.
Fifth, large water surface mixed culture
Large water surface mixed culture of Pelteobagrus fulvidraco, group production is high, does not affect the yield of the main species, but also do not need to bait. Generally mu put 40 to 60 catches of Pelteobagrus fulvidraco, specifications 3 cm / tail ~ 4 cm / tail, can mu increase Pelteobagrus fulvidraco 8 kg ~ 15 kg.
No matter what kind of mix-culture method is used, the following matters should be noted in culture management:
One, keep the water body with high dissolved oxygen. Pelteobagrus fulvidraco has a high demand for dissolved oxygen in pool water, so it is required to have fresh water and sufficient dissolved oxygen when mixed culture is practiced, and new water should be added at the right time during the growing season, and water should be changed diligently during the high temperature season, and it is better to keep the micro-flow water.
Two, maintain a reasonable stocking density and stocking specifications. According to the water body bait biomass, scientific and reasonable to determine the mixing ratio and stocking specifications, the general water body to mix 30 to 60 tail is appropriate, stocking specifications for 3 cm / tail ~ 4 cm / tail. If the density is too large, the specification is too small, the end of the year can not reach the market specification.
Three, the fish pool mixed with Pelteobagrus fulvidraco is no longer suitable for mixing with other carnivorous fish, freshwater marsh shrimp, freshwater crayfish in the aquaculture pool should not be mixed with Pelteobagrus fulvidraco.
Fourth, in the process of breeding, if you find that the specification of Pelteobagrus fulvidraco is too small, it means that the natural bait biomass is insufficient in the fish pond, so you can make up for the small miscellaneous fish and shrimp, the summer flower of the domestic fish, or feed the artificially formulated special Pelteobagrus fulvidraco bait. When feeding artificial bait, the main species should be fed first (into the shallow water), and then the yellow catfish (into the deep water). Pelteobagrus fulvidraco has the habit of living day and night, and baiting should be done mainly at night.
Fifth, the crab pool mixed with yellow catfish, because the river crab, yellow catfish in the ecological position in the same water layer, easy to cause the two ecological position competition. Therefore, the crab pool must maintain sufficient natural bait organisms, otherwise it will affect the feeding effect of Pelteobagrus fulvidraco. You can put 300 kilograms to 400 kilograms of snails and some egg-carrying crucian carp and egg-carrying prawns per mu in the crab pond beforehand, so that they can reproduce naturally for the river crabs and Pelteobagrus fulvidraco to feed freely.
Techniques for controlling common diseases of Pelteobagrus fulvidraco
Pelteobagrus fulvidraco is a widely distributed demersal economic fish in freshwater water bodies in China, and while improving the yield per unit area, increasing the stocking density and expanding the aquaculture area, diseases of Pelteobagrus fulvidraco have gradually increased and the hazards have increased. For this reason, the main control techniques of several common diseases are proposed.
One, mechanical injury etiology
Because Pelteobagrus fulvidraco prefers to live in clusters, its pectoral fins and dorsal fins are long with hard spines, which is easy to cause mechanical injuries such as skin abrasion, cracked fins and other mechanical damages in production operation and transportation, secondary bacterial infection and mycobacterial infection, and rotting fins and growth of water molds as the main symptom.
Epidemic situation
Mainly for the net box sub-culture operation and large-size fish species after long-distance transportation injury.
Disease control techniques
In pulling net exercise and transportation should be carefully operated. When the fry are released, the time of the temporary net box should not be too long, and the stocking density of the temporary box should be reduced as much as possible. The water used for transportation can be added with appropriate amount of hygromycin, and the fish species should be disinfected with a low concentration of potassium permanganate or 30% saline solution by dipping before entering the pool or the net box.
Two, hemorrhagic edema disease
Cause
Caused by bacterial infection. Diseased fish body surface yellowish, mucus increased; pharyngeal skin broken congestion of round holes; abdominal expansion, anus red, swollen, turned out; head congestion, dorsal fin swelling, pectoral fins and ventral fins at the base of the congested, ulcerated fins, and even the abdomen from the pectoral fins to the abdominal fins longitudinal fracture, bile exudation. The abdominal cavity is sloughed with a large amount of blood or yellow frozen gelatinous material, there is no food in the gastrointestinal cavity, the stomach is pale, the intestines are filled with yellow thick liquid, the liver is earthy yellow, the spleen is necrotic, and there are moldy black spots on the kidneys. The disease is most harmful during the breeding of fry or adult fish, especially more prevalent in the process of fry cultivation, with a mortality rate as high as 80%. In the high-temperature season, the disease is easy to outbreak and fierce, spreading fast.
Disease control techniques
During the breeding process, close attention should be paid to the water quality, maintain good environmental conditions, and keep the dissolved oxygen content above 5mg/L; appropriately reduce the stocking density of the fry; after the disease occurs, disinfect the water body once a day for three consecutive days. When feeding fish slurry, 1% salt should be added to the bait every day.
Three, water mold disease
Cause
Caused by water mold infection. Water mold first parasitic, the naked eye can not see the difference, when the naked eye can see, the mycelium has invaded the wound and to the inside and outside of the growth and spread of diffusion, was like gray-white cotton-wool-like adherents, the sick fish swimming disorders, restlessness, until the muscle rot, loss of appetite, weak and dead; if the fish eggs are covered with mycelium, the white pom-pom-like, moldy eggs to become the death of the fish eggs. Serious harm to eggs in hatching and fish body surface with wounds in the fry and adult fish. This disease is most likely to occur when the water temperature is low, mostly caused by improper operation in the process of pulling nets, separating boxes and transportation.
Disease control techniques
In the process of catching, transportation and stocking, try to avoid injury to the fish body, and master a reasonable stocking density. Before the fish species are placed in the pond, disinfect the pond with a salt water solution with a concentration of 2-3%, splash methylene blue on the whole pond so that the pond water reaches a concentration of 2mg/L, and then splash it again 2 days later. Fertilized eggs should be strictly disinfected before hatching, and the water temperature should be preferably controlled at 26～28℃, and the fertilized eggs should be disinfected again during the hatching process.
Four, enteritis disease
Causes
Caused by infection with punctate aerobic monosporidium. Diseased fish abdomen is enlarged, anus red and swollen, light pressure on the abdomen, the anus has yellow mucus outflow. Cut open the abdomen of the fish, the body of the less sick fish esophagus and foregut congestion and inflammation, severe inflammation of the whole intestine was light red, blood pus filled with intestinal tubes. Sick fish swim alone, slow activity, loss of appetite. Enteritis mainly affects fish species and adult fish. The infection may originate from the bottom silt of aquaculture waters, and the zooplankton and earthworms ingested by the fish as well as the fish slurry in the artificial compound feed may also carry the disease. The peak of the epidemic occurs when the water temperature is 25 to 30 degrees Celsius.
Disease control techniques
The pond should be thoroughly cleaned and disinfected; not feeding moldy and rotting feed, live bait should be disinfected with 2-3% salt solution, and 1% salt or 0.1% fresh garlic juice should be added to the feed for feeding on a regular basis; and the whole pond should be sprinkled with 0.5g of dibromohydantoin per cubic meter.
V. Rotifers
Causes
Caused by the parasitism of rotifers. The sick fish are restless, and when seriously infected, they swim wildly along the edge of the pond, presenting the phenomenon of "running horse"; microscopic examination shows that a large number of rotifers are parasitized on the gill filaments of the fish and the mucus of the skin. The disease mainly affects Pelteobagrus fulvidraco fry and species, and mostly occurs in late spring and early fall.
Disease control techniques
Splash the whole pool with 0.7g of copper sulfate and ferrous sulfate combination (5:2) per cubic meter, or use neem leaves 30kg/mu to decoct and then splash the whole pool with broth.
Six, small melon worm disease
Causes
Caused by the parasitism of multinucleate small melon worm. In the sick fish body surface naked eye visible small white spots, serious body surface seems to be covered with a layer of white film; microscopic examination of gill filaments and skin mucus, see a large number of small melon worms. The breeding temperature of Cucurbita pepo is 15～25℃, and it is popular in spring and fall. When overcrowding, insufficient bait, fish thin, the fish is easy to be infected by small melon worm.
Disease control techniques
Wash the fish body with 50-60g of formalin per cubic meter for 10-15 minutes, at the same time, the onset of the fish pool is also disinfected with formalin; the whole pool is splashed with 2g of methylene blue per cubic meter, several times in a row, once a day.
Seven, anchor head flea disease
Cause
Caused by anchor head flea parasites. In the early stage of the disease, the fish is restless, slow swimming, fish body wasting and other phenomena. The parasitized part is congested and inflamed, swollen, and red spots appear. Anchor flea parasitism is visible to the naked eye.April to June is the epidemic season.
Disease control techniques
With 90% crystal trichlorfon whole pool splashing, so that the pool water concentration of 0.3 ~ 0.4g per cubic meter, the efficacy of significant.
Eight, nutritional diseases
Causes
The nutritional diseases of Pelteobagrus fulvidraco are caused by too much or too little nutrients in the feeds, denaturation of the feed ingredients or insufficient energy. Common symptoms include fatty liver disease and vitamin deficiency. The liver of sick fish is enlarged, the color of liver is pinkish white or yellowish, the gallbladder is enlarged, the bile is black, and the pancreas is pale. Sick fish die sporadically.
Disease control techniques
Improve the feed formula, improve the quality of feed, and appropriately increase the amount of vitamins and inorganic salts in the feed.
In the control of common diseases of Pelteobagrus fulvidraco, we should adhere to the policy of "prevention is the mainstay, prevention is more important than cure", and do a good job of preventive measures: ① Thoroughly clear the pond and strictly disinfect. ② When stocking seedlings, use salt and other drugs to disinfect the bath. ③Raising healthy, disease-free seedlings. ④Feed fresh, high-quality feed, adhere to the "four", "four look" feeding methods, do not apply unfermented manure. ⑤ Strengthen water quality management, and change water regularly. (6) Splash medicines regularly to disinfect the water and take medicines orally, and insist on disinfecting the live bait, feed table and food ground. ⑦Find fish disease, timely diagnosis and treatment. It should be noted that: Pelteobagrus fulvidraco is a scaly fish, it is sensitive to copper sulfate, potassium permanganate, trichlorfon and other drugs, especially to be used with caution.