Pelteobagrus fuliridraco Richardson is a freshwater small-bottomed fish, and it is a best-selling aquatic product on the market. In recent years, due to excessive manual fishing, the production of natural waters has been very low, and research on artificial development and utilization is imminent. 1 The biology of the stingray The stingray has a long body, flat ventral surface, slightly flattened posterior half of the body, and a large, flat head. It has a blunt kiss, a large palpebral fissure, a lower jaw, a slightly longer upper jaw than the lower jaw, and upper and lower jaws with fine hairs. Eyes small, lateral, slightly elevated eye interval; to be 4 pairs, the nose must reach the posterior edge of the eye, the maxillary must be the longest, after extending the base of the pectoral fin; 2 pairs of beard, lateral 1 pair is longer than the inner 1 pair. Dorsal fins II, 6 ~ 7; anal fins 19 ~ 23; zygomatic lateral 14 ~ 16; vertebrae 36 ~ 38. The body length was 3.8 to 4.2 times the body height, 3.6 to 4.2 times the head length, 6.7 to 7.8 times the tail shank length, and 9.4 to 11.8 times the tail shank height. The head length is 2.9 to 3.8 times the length of the kiss, which is 4.6 to 6 times the eye diameter and 2.1 to 2.3 times the eye distance. The dorsal fins do not branch, the fins are hard thorns, and the trailing edges are serrated. Pectoral fin spines are more developed, and the front and rear edges are serrated, with 30 to 45 fine serrations at the leading edge and 9 to 17 coarse serrations at the posterior edge. The pectoral fins are slightly fan-shaped and the ends are near the pelvic fins. The pelvic fins are shorter than the anal fins and their ends are free. The body is dark brown on the back, yellow on the side of the body, and 3 pieces of intermittent black stripes. The belly is light yellow and the fins are gray and black. Stingray is a widespread fish, omnivorous, mainly prey on small fish, shrimp and aquatic insects. During the reproductive season from mid-May to mid-July, the water temperature changes from 23 to 30.5°C. Spawning activities take place at night. Generally 2 years of age mature, a small number of 1st-age sexual maturity, the smallest mature individual female body length of 11.7cm, male body length 14.8cm, fecundity of 1086 ~ 4469. The stingray is fertile yellow, sticky, sinks at the bottom of the nest or attaches to aquatic fibrous roots and other objects. The diameter of the egg membrane is 1.9-2.2mm, and the yolk diameter is 1.4-1.5mm. When the water temperature is 23-27°C, about 48-60h. hatch. 2 Feasibility of development and utilization of yellow snapper 2.1 High meat content and high nutritional value According to Huang Feng et al. (1999), the meat content of yellow catfish varied from 66.47% to 68.41% with an average of 67.53. %, which is close to famous fish such as squid (67.62%) and Nile tilapia (67.18%), belongs to fish with higher meat percentage. The protein content of the sturgeon was 15.37%, the total amount of amino acids was 14.19%, the essential amino acid content was 5.87%, and the essential amino acid index in the muscle of the sturgeon was 73.34, which was higher than other fishes except for salmon, and the lysine content was high. Exceeds egg protein standards. Therefore, it can be considered that Stingray is a nutrient-rich, high-quality fish and is a fish resource to be developed and utilized. 2.2 Wide temperature adaptability, suitable for feeding under various climatic conditions China has a vast territory with numerous rivers and includes five climate zones: tropical, subtropical, temperate, cold and temperate, and frigid. Stingray is a fish with wide temperature adaptability. In addition to the southwest, northwest, and a few areas in China, the Yangtze River, Yellow River, Pearl River, and Heilongjiang River Basin all have a large number of distributions, which has created favorable conditions for the development and utilization of Stingray. 2.3 There has been a breakthrough in artificial breeding techniques, which has made it possible for stingrays to shift from wild to artificial breeding. 2.4 The market prospects are promising Because the natural resources of stingrays have been drastically reduced, the price of stingrays in the market has been increasing year by year, and the demand is large, which has a good market prospect. Stingray also has huge market potential in Japan, South Korea, Southeast Asia and other countries, and is an excellent breed of foreign exchange earned through exports. 3 Artificial breeding of stingray 3.1 Artificial propagation 3.1.1 Collection and cultivation of broodstock Broodstock can be harvested from natural waters or from ponds. When the broodstock is selected, it requires the mother to be above 50g, the male parent is above 100g, and the body side has a clear marking and no disease or injury. The broodstock is sterilized with 3% saline for 10 minutes before stocking, and then put into the pool. The stocking rate is 100-150kg/667?, and the ratio of male to female is 1:1. In the first half of March, the male and female broodstock will be bred in separate ponds. When the water temperature exceeds 15°C, feeding is started, and fresh fish, shrimp, snail meat, etc. are used. For the bait, the minced meat is used to make the minced meat. It can also be crushed with a knife and fed at a fixed point. From late April to early May, two shots were made on a daily basis and the amount fed was 1% to 3% of the fish's body weight. After the middle of May, it was fed 3 times a day, and the amount fed was 5% to 8% of the fish's body weight, which was appropriately adjusted according to the fish's feeding status. Pay attention to do a good job of water quality management, the early water depth of 0.8 ~ 1.2m, later 1.2 ~ 1.5m, every 7 ~ 10d new water, each time 10 ~ 20cm, transparency control at about 40cm, dissolved oxygen 4mg / L or more. 3.1.2 Identification of broodstock maturity Females have gonopore and urinary foramen, during the breeding season, the abdomen of females is swollen and soft, and the genital hole is slightly red. The broodstock matures well and exerts pressure on the abdomen with the outflow of eggs. The outline of the ovary is obvious. Males have only excretory holes and are papillary and breeding. Mature gonads of mature males reach the end of the excretory holes, but they still cannot squeeze semen. 3.1.3 The artificial breeding of artificially propagated yellow catfish can adopt natural breeding and artificial production. For natural breeding, a spawning pond is built, usually with a small pond of 0.27 to 0.4 hm2. The pond is sterilized thoroughly and a suitable amount of small stones or roots are placed in the pond for spawning. The sexually mature broodstock is harvested from natural waters or artificially cultivated, and the ratio of males to females is put into the spawning pond at a ratio of 1:1. The stocking density is 120-150 pairs/667 ,, and the intensive breeding is carried out to feed animal species mainly including small fish and small shrimps. The bait is properly fed with tender leaves containing vitamins to promote gonad development. Usually in the first half of May, the broodstock began to pair up to nest and spawn. Because the stingray has the habit of protecting the eggs and protecting the young, the eggs are usually hatched in the original pool during reproduction, and the eggs can be collected and concentrated to hatch if conditions permit. Artificial oxytocin production, generally using DOM, HCG, LRH? A and PG have oxytocin effect, using PG alone or mixed with several other hormones have good effect. Two-needle injections should be given to individuals who have had poor sexual maturity during the early stages of the stingray breeding period. The interval between two needles is 20 to 24 hours. The specific interval time depends on the water temperature. In the late post-breeding and sexually mature individuals of stingrays, one shot can be used, with an effect time of 18 to 28 hours. It is better to use the base of the pectoral fin at the injection site. When injecting, the needle should be shallow, 2 to 3 mm, and the injection direction should be at an angle of 45 degrees with the abdomen of the body axis. Injection under the dorsal fin can also be used. The injection dose should be controlled at 0.1 to 0.2 mL/tail. After spawning of the stingray, the fertilized eggs are left to hatch in the original pool. 3.2 Seed Breeding of Stingray 3.2.1 Pond preparation Fish breeding ponds should be 0.27~0.4hm2 each, with a water depth of 1.5m. At the end of March, clear ponds should be disinfected, excessive silt should be removed, and ponds should be reinforced. Maintenance and drainage facilities. Introduce fresh water and apply 300 to 500 kg/667 lb. of livestock manure, and cultivate large clams such as Cladocera and Copepoda to feed fry. 3.2.2 Reasonably put a large number of acarids in the fish pond, when it appears, you can put in the yellow carp seedlings, generally put 40,000 to 60,000/667, and if the stock is divided, the fish stocking density can be increased. The stocking rate can reach 80,000 to 100,000 tails per 667 feet. When the fry grows to more than 1 cm, it is raised in separate ponds. 3.2.3 Bait Feeding In addition to making full use of the natural feeds in the cultivation ponds, it is also appropriate to feed the paste feeds. It is processed into paste with small fish, shrimp, snails and other animal feeds. It is fed twice a day. It is fed once a day in the morning and evening. It is mainly in the evening, and the daily feeding amount is 2% to 5 of the body weight of the fish. %, according to the fish's diet and weather, water quality, etc., appropriate adjustments. Can also be fed compound feed, Chen Yijun, etc. (2000) with their own preparation of feed (1 fish meal, 2 cakes, 2 pieces of wheat flour plus water into a group) feeding, the effect is better. 3.2.4 Water Quality Control Generally, the water is changed once every half month, each time changing water 1/4 to 1/3, to keep the water quality live and cool, and to promote the growth of fingerlings. 3.3 Adult Breeding of Sablefishes Currently, the breeding mode of Sablefishes includes large-water polyculture, pond aquaculture, net enclosure culture, cage culture, and aquarium aquaculture. This article focuses on the introduction of pond adult fish culture techniques. 3.3.1 The requirements of ponds for main pond raising are not strict. The ponds and cement ponds with sufficient water sources and good water quality can be used for stingray breeding. The pond water depth is generally about 1.5m, and the size of the area can be determined according to the scale of breeding. 300 to 2500? Before the fish is put in the pond for 10 to 15 days, 200 g/L of fresh lime slurry should be poured evenly over the whole pond, and 500 g/l of fermented organic fertilizer should be applied to breed natural food organisms for feeding by stingrays. In the first 2 days after the disinfection of the pond, 0.8 to 1 m of water is generally added, and the organic fertilizer is applied to the 3rd to 4th days. After the toxicity disappears completely, the fish is put into the fish. The stocking time of stingray fingerlings is generally from March to April of each year. Generally, sturgeon species with a tail weight of 10 to 20g are 2,000 to 3000 tails per 667 feet. In order to make full use of the water space and food resources to facilitate water quality regulation, it is possible to mix about 600 cm of squid species with a length of about 15 cm per 667 水 of water surface, 200 species of squid species and 200 species of first-year grass species. Pay attention to the fish species before stocking, use 3% to 5% of salt water to dip 10 ~ 15min, and first put the yellow sturgeon species, 10 ~ 15d after the stocking of other fish species, in order to facilitate the growth of the main fish. Since stingrays are omnivorous fish, artificial feeding can feed animal feed such as small fish and shrimp, snail meat, livestock and poultry processing plants waste, fish meal, etc., and can also be fed to bean cakes, peanut cakes, bran, bean dregs, etc. Plant feed can also be fed artificial compound feed. Wang Xingli et al. (2000) introduced two formulas: Formula 1: fishmeal 10%, bean cake 25%, vegetable cake 30%, bran 20%, barley 10%, corn 5%, plus bone meal 1%, salt 0.5%; Formula 2: Fish meal 15%, bean cake 35%, bran 30%, corn 5%, eucalyptus leaves 5%, barley 8.5%, growth hormone 1%, salt 0.55. Daily feeds accounted for 2% to 7% of the fish's body weight. They were fed once a day in the afternoon and afternoon in the afternoon. The amount of feed in the morning accounted for 1/3 of the total feeding amount in the morning and 2/3 in the afternoon. Pay attention to do a good job of water quality regulation, generally 4 ~ June, every 15 ~ 20d water injection 1, 7 ~ September, every 7 ~ 10d water injection 1, each time adding water 10 ~ 15cm, keep the water quality fat, live, tender, cool, The transparency is about 35cm. At the same time pay attention to the prevention and treatment of fish diseases. 3.3.2 Pond pond raising The nesting of yellow catfish is a method of raising a small amount of yellow catfish when raising fish in a conventional pond. Generally, 30 to 40 g/tail of stingray 60 to 70 tails/667 are stocked. The conventional cultured species and the proportion of the main cultured in the pool are carried out according to the original culture methods. The rearing and management are also conducted according to the conventional fish farming practices. Generally, the fine cultured fish ponds do not increase other inputs on the basis of the original culture scale. Can increase the production of stingray more than 10kg, increase income more than 200 yuan.
Filter Media For Water Treatment
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