1. Parental shrimp spawning?

Parental shrimp spawning is the selected parental shrimp placed in the spawning pool or nursery pool spawning. The next morning will be removed from the parent shrimp, the hatchlings are collected, counted, and put into the nursery pool cultivation. Some hatcheries have special spawning pools, some are used as spawning pools, but the structure of the special spawning pools and nursery pools are no different, are about 40 cubic meters of large pools, only the number of air stone hanging less. This spawning method of articulated larvae are collected and moved into the nursery pool, can reduce the pollution of the nursery water by pro-shrimp; spawning pool of pro-shrimp can be fed feed, can not be spawned pro-shrimp in a larger space is easy to get fully mature, pro-shrimp have a larger spawning space, egg hatchability is high, and is now widely used in shrimp nursery farms.

Parental shrimp more spawning at night, spring spawning at night from 21:00 to midnight, October is more in the latter half of the night 1-3:00 spawning. Parental shrimp spawning swim up to the surface, swimming along the pool wall, discharged eggs into the mist. During spawning, do not disturb the shrimp, so as not to affect spawning. A tail of artificially ripened shrimp spawning volume of 100,000-20 million, and spawning conditions and maturity. A spawning time and time several nights to complete, this time can be found in the shrimp incomplete gonads, sometimes the gonads do not reach full development that has begun to spawn. These are bad phenomena, but have little effect on the quality of eggs. Parent shrimp can be moved back to the maturation pool the next morning.

2. Fertilized eggs hatch and neritic larvae to the pool?

(1) Fertilized eggs hatch? Parent shrimp spawning in the nursery pool fertilized egg incubation in the original pool, can be applied to the spawning pool beforehand 2 × 10-6-10 × 10-6 EDTA disodium and 1 × 10-6 hygromycin, in order to neutralize the heavy metal ions and reduce bacterial infestation, improve the survival rate. Because heavy metal ions have a greater impact on embryonic development, you can also change the water in the middle of incubation, i.e., using the relative density of fertilized eggs (bottom-sinking), change the upper layer of water to improve water quality and improve the hatching rate. Fertilized eggs late incubation needs to be carried out under aerated conditions to prevent the eggs from sinking to the bottom of the pile and hypoxia. Eggs in the just produced floating better, it is easy to observe the number of daily management should be more observation of the spawning of shrimp, estimate the number of eggs, regularly check the fertilization rate of eggs, so that in the hatch out of the unseasoned larvae before the number of slightly know the number of eggs produced that night, estimate the number of eggs hatch out of the unseasoned larvae, and to do a good job in the nursery pool standby work. Incubation water temperature is generally maintained at the same temperature as the spawning water.?

(2) The jointless larvae are divided into pools? Fertilized eggs hatch out for the jointless hatchlings, jointless hatchlings rely on their own yolk nutritional development, do not need to feed, pay attention to good water quality can be cultivated. The use of its strong adaptability to environmental changes can be collected and moved to the pool. Production is the use of this feature, to achieve the purpose of controlling the density of larval culture and purification of water quality; can also be collected and sold the jointless larvae. Determine the number of jointless larvae in the hatchery or nursery pool is a key task. According to the production needs by determining the number of hatchery larvae without joints transferred to other pools. Nodeless larvae cultivation is the beginning of shrimp larvae cultivation, control of appropriate density is particularly important, the general production requirements per cubic meter of water to put 150,000 -200,000 tails. Cultivated under a small amount of aeration, without water changes. The water temperature of the nursery pool can be controlled at 1-2 ℃ above the spawning pool. If the production of Japan's "colony method", the nursery should be inoculated in the second stage of the neritic larvae fertilization of the pool, and can be adjusted to the appropriate light, in order to facilitate the propagation of algae. Other nursery methods need to be cultivated under appropriate conditions.

This is the Japanese shrimp parent shrimp spawning and fertilized eggs hatching ways and means, which has a lot of technology we need to learn. I hope it will be helpful to all shrimp farmers.