Techniques for large-scale breeding of puffer fish

The puffer fish egg is small and the egg diameter is only 1. About 1 mm, high gonadal index and large number of eggs, which creates a prerequisite for large-scale breeding. Large-scale seedling breeding should also grasp the following technical links:

First, a sufficient number of parent fish with well-developed gonads is a prerequisite for obtaining a sufficient number of high-quality eggs. Only when the number of parent fish is sufficient, the number of eggs used for breeding can be guaranteed; only when the gonads of parent fish are well developed, can the quality of eggs be guaranteed, both of which are indispensable. The quantity of parent fish can be satisfied by storing or selecting from the backup parents, while the quality of parent fish needs to be strengthened by creating a suitable ecological environment and using the method of the combination of physiology and ecology to make the gonad development of parent fish well. so as to ensure the quality of parent fish, and finally ensure the quantity and quality of parent fish eggs.

Second, accurately grasp the timing of induced labor and effect time, which is a prerequisite for normal fertilization of eggs and improvement of fertilization rate. During the induction of labor, the necessary environmental factors should be ensured, and the timing of induction should be grasped, and the eggs should be induced at the end of Ⅳ period. The type and dose of drugs should also be used properly to ensure the transformation of eggs from the end of Ⅳ to Ⅴ, otherwise they may not give birth or are overmature, resulting in failure of induced labor. Accurate timing is equivalent to increasing the number of parent fish (or saving the amount of parent fish), which is particularly important for the unit with insufficient parent fish.

Third, the appropriate incubation environment is conducive to the healthy development of fish embryos and the later cultivation of fish fry. The hatching container should be non-toxic, the temperature, salinity, PH value and illuminance during hatching should be suitable, the water should be changed frequently, and the daily water exchange rate should reach 100%, which is beneficial to improve the hatching rate. During the artificial breeding of our research group in 1999, the hatching rate of fertilized eggs of many groups of parent fish reached more than 95%.

Fourth, attention should be paid to the type, density and feeding mode of bait when cultivating fish fry.

The water quality should be kept fresh so that the fish fry will eat actively, be healthy and grow quickly. In the food series of puffer fish fry cultivation, special attention should be paid to the types of bait, the time and mode of switching to food, which are the main factors affecting the cultivation of puffer fry. Unpalatable bait, poor food conversion and cannibalism can lead to 50% or even higher mortality of fry, and may eventually lead to the failure of breeding.

As long as the breeding units have specific technical measures and operating procedures in the above four aspects, and grasp all aspects of each technical link, then the large-scale breeding of puffer fish will certainly be successful; on the contrary, mistakes in any link will affect the emergence of puffer fish seedlings, and even lead to the failure of breeding. If the operation is successful, 1 tail 1. After artificial insemination of 5 kg female parent fish, the number of black larvae can reach 100,000.