1. broodstock selection off. Big-mouthed broodstock should be picked from different rivers in order to avoid inbreeding. The weight is generally 2.5 to 5 kg. It cannot be too big or too small. Too much food can be difficult to handle. It is not easy to cultivate, and it is not the greater the amount of ovum. The age of over-maturity is not necessarily reached and it takes a long time to grow in the pond. Male and female broodstock ratio of 1:1. 2. The bred fish domesticated off. In practice, we have found that sexually mature brood fish that have just been taken from rivers have been found to be very difficult to produce by hand, and often cause broodstock to die. This is mainly due to the sudden change of ecological conditions, which inhibits the development of the gonad gonads, and the injection of exogenous hormones causes disruption of the endocrine system. However, after one year of adaptive cultivation of the pond, the broodstock adapted to the pond's ecological environment, and the gonads could be developed early and the artificial oxytocin would be successful. At the same time, the domesticated broodstock is much more gentle than the broodstock captured in the river, and the oxytocin operation is also much smoother. 3. Broodstock cultivation. We will breed them in adult fish breeding ponds, 3 to 5 tails/mu, and cast more bonito fish species to meet the nutritional needs of big oysters and meet the requirements for artificial breeding. 4. Artificially promote familiarity. In order to ensure that the gonad gonad development is consistent, the amount of female oviposition fish and the amount of semen of the male broodstock were increased. The injection of low-dose LRH-A4 or LRH-A51 to 1.5 μg/kg was performed 10-15 days before artificial oxytocin production. The fish is injected at the same time. 5. Artificial quarantine. We summed up the following two options: (1) injection of HCG 2500 ~ 3000 units / kg, male and half fish, this program should use artificial insemination, because HCG stimulation is too strong, often after the injection will cause the broodstock, while estrus When the male bred fish bites the female. Therefore, male and female broodstock should be divided into open and raised, and care should be taken to prevent death from jumping out of the pool; around 12 hours, remove the broodstock, wipe the water off the broodstock with a towel or old soft cloth, and prepare the basin and saline solution in advance. , stainless steel cuvette and dissipated brown tablets. First discharge the urine from the male and then squeeze the female eggs into the pot. Then, squeeze the male semen into a small cup, dilute it with an appropriate amount of normal saline, and pour it into the egg. The action should be quicker. Use your fingers to stir quickly. 1 to 2 minutes, then sparsely affixed to the brown tablets, 10 to 15 minutes after the eggs produce adhesion and hatch into the pool. (2) Injection of DOM 1 to 5 mg + LRH-A 22 to 5 μg/kg or 1 mixed hormone 40 units/kg. Half of the male fish, this program can overcome the drawbacks of HCG injection, natural spawning method can be used to reduce the operating trouble. First arrange the disinfected brown tablets in the fish spawning pool. The broodstock can be directly placed into the spawning pool and flushed at the right time. After spawning, slowly drain the pool to catch the broodstock. 6. Incubation management. Check the density of the eggs on the brown tablets carefully. If the density of the egg on the brown piece is too high, it should be dispersed on the other brown piece. In the original spawning pond, hatching tank or small cement pool, the hydrophile or microfluidic water incubate. If the egg turns white after 12 hours, it will be non-fertilized egg. 60 to 70 hours out of the film.
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