The crystal sardines of the genus Papilionus are in the form of oystercatchers, fishes of the genus Mansoni, and genus of fishes. Native to Malaysia, Thailand and other places, it is tropical and subtropical fish. In addition to the crystal puffin fish, there are white paddock, black padding, and Pahang river Buding. Crystal pudding is of good quality, with no spurs and delicious taste. Generally, freshwater fish have a bad taste after being frozen, but the crystal pudding does not change its taste after being frozen. This is a great advantage of the crystal pudding, which is very popular with consumers. The crystal puddling grows rapidly, with body weights of up to 1.5 - 2.0 kg for Malaysian infancy fish and up to 4.0 kg for class II fish. The first batch of fry introduced by the South China Sea Fisheries Research Institute of the Chinese Academy of Fishery Sciences was cultured for 4 months at the aquatic breeding ground in Foshan and the average weight reached 475 grams, which is suitable for breeding in the tropical and subtropical waters of China. The crystal pudding fish is of mixed diet and has a low requirement for the protein content in the feed. The crystal pudding can be cultured with tilapia feed. Breeding management is convenient. In 2000, the South China Sea Fisheries Research Institute introduced crystal budding fish from Malaysia to grow broodstock and artificial breeding. The artificial breeding situation is described as follows: Broodstock Cultivation The South China Sea Fisheries Research Institute of the Chinese Academy of Fishery Sciences imported a batch of 1.5-year-old crystal paddlefish from Malaysia in autumn and winter of 2000, with an average weight of 2.5 kg, in the aquatic breeding ground in Foshan City. Breeding, autumn and winter water temperature is low, in the wintering shed rearing, feeding a lower amount, feeding the amount of fish body weight 1% -3%. After the spring begins, as the temperature rises, the water temperature also rises, and the gonads develop more quickly. At this time, the amount of feeding is increased, and the feeding amount is 3% to 5% of the fish's body weight to ensure the nutritional requirements of gonadal development. . After more than half a year of pond cultivation, the average body weight reached 4.5 kg. After inspection, the gonads were fully developed and matured. Pre-production pull nets to check the maturity of fish gonadal development. The abdomen of the female fish is swollen, soft and elastic, and the reproductive hole is red and open. With an egg dig you can dig a full-orange egg. The crystal egg puffin has a small egg diameter of about 0.9 mm and the egg membrane is thicker. Under the microscope, it is difficult to distinguish the oocyte development to the first few phases. At present, it is mainly distinguished by eyes, observing the fullness, color, viscosity, and shape of the fish body to distinguish whether the sex gland of the female is mature. The abdomen of the male fish is not very round, and the infra-red projection of the reproductive hole is conical. The testis is dendritic and the spermatorrhea is not smooth. For example, the spermatozoa of the male reproductive quill are mature and can be artificially inseminated. Artificial insemination The oxytocic agent used in this artificial insemination is commonly used in domestic fish, such as HCG, LRH-A 2 and DOM, which are used after being formulated. According to the ratio of male to female ratio of 1:1, injecting oxytocic acid, the oxytocic acid is divided into two injections, two time intervals are 10 hours, the effect time is 8 hours, and the whole process of oxytocin takes 18-20 hours. The oxytocin effect depends on the maturity of broodstock, The water temperature, the oxytocin production dose, and the injection site are slightly different during oxytocin production. Prepare male and female fish for artificial insemination, first female and then male, wipe the fish body, squeeze the egg into the egg container, and then quickly squeeze the semen of the male fish into the egg container and squeeze the eggs while using the chicken feathers. Stir the eggs, fertilize the eggs in the vessel, and transfer the fertilized eggs to the hatchery. There are many attachments in the hatchery and the fertilized eggs will automatically adhere to the attachments and then hatch. Accurately grasping the effect time is the key to the success of artificial insemination. Premature artificial insemination, immature egg is not mature, and it is difficult to inseminate. Infertility is too late and the egg is too mature. The best time to miss insemination affects the fertilization rate. Injection site and water temperature have a greater effect on the effect time. Pectoral fin injection is usually the fastest and the intramuscular injection is slower. The difference between the two drug efficacy time is about 1-2 hours, sometimes even more. The effect of water temperature on the efficacy is particularly obvious. When the water temperature is lower than 27°C, the fertilization effect is poor. From repeated trials, it was found that the crystal puffer fish used intramuscular injection at a water temperature of 29°C-31°C, and the efficacy time was 18 hours, and the oxytocinization effect was the best, and the oxytocin success rate was more than 80%. The artificial hatching will transfer the fertilized egg applicator into the hatchery pool for incubation. The hatching pool is an indoor rectangular cement pool with a volume of 4 cubic meters. The hatching pool water temperature is 29°C-31°C, continuous oxygenation, and the fertilized eggs are processed for 16-18 hours. , hatched larvae. The time required for the development of fertilized eggs at each stage is shown in the table below: Time required for each stage of development Incubation time Development period 2 hours Cleavage period 4 hours Blastocyst stage 7 hours Gastic period 18 hours Breaking the membrane Small fish rupture membrane 10 After hours, the amount of oxygen was increased and the fertilized egg applicator was removed at the same time. At this time, it was transferred to the fry cultivation stage. In this experiment, a variety of methods were used to hatch fry, but what kind of hatching method is better is a problem in the incubation of crystal sardines. Crystal paddlefish eggs are viscous eggs, and they have been successfully hatched after fertilization or not. However, judging from the experimental results, the effect of non-sticking and hatching is better than that of de-bonding. According to reports, the majority of Malaysian crystal puffer hatches are de-bonded and hatched. Therefore, the hatching conditions and facilities affect the crystal pudding. Fertilized egg development is an important factor. Especially before the gastrointestinal phase, different hatching conditions always affect the development of the embryo. These conditions include: water temperature, water depth, whether the water is flowing, whether it is oxygenated, the amount of oxygenation, whether it is de-bonded, whether the fertilized egg applicator is , How to place the fertilized egg attachment device, etc. Through several experiments, the author believes that non-sticking and hatching is better, and is relatively simple. Incubation is performed in a microfluidic manner with proper oxygenation. The water depth is controlled at about 30 cm and the applicator is laid flat so that the best effect of hatching can be achieved. . The fry raises the newly hatched larvae with a total length of about 3.0 millimeters and is small in size. It is cultivated in the original pool of aerated and microfluidic water. The newly hatched larvae have a large yolk, a transparent body color, a cuddly shape, and occasional spiral movements. They can swim horizontally for 10 hours after filming, and have a high frequency of fishtail swing during swimming. Around her, she maintained her life with her own yolk, and her yolk absorption was completed on the third day after hatching. At this time, the fry was about 8.0 mm in length and began to feed on food. Ingestion of smaller branches, copepods, etc. in the first period, feeding 4-6 times a day, maintaining a depth of 30-40 centimeters; after 5-10 days, the larger branches of the horns, cockroaches can be fed Classes and worms, etc., the water level increased to 50-70 centimeters; after 17 days, when the fish body is 3 centimeters long, the fish body is pink, and the body shape is basically similar to the adult fish. At this time, the powdered squid feed can be fed. The water level is maintained at about 80 cm. The whole process of fry breeding changes water 1-2 times a day, changing the amount of water for each time is about 30%. When the fish body is up to 3 cm, it can be moved to the outdoor cement pool for cultivation. When the fish body reaches 5-6 cm in length, it can be Put in pond culture.
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