1, to master the season: the river raft at the peak of reproduction gonad fullness. High fertilization rates, high hatching rates, and high rates of larval metamorphosis can yield high yields; otherwise it will affect yield. 4.4 If there is too much sperm, it will affect the normal development of fertilization and embryos can use egg washing liquid to kill part of the sperm and increase the fertilization rate. See Table 1 Table 1: Effects of egg washing liquid on fertilization rate Number of developmental examinations Number of developmental normal necrosis and fertilization (post-sac) The larvae do not feed after filming After the larvae are filmed, they are cast into artificial live baits. 6.5 Drain the bottom of the pool every day. The tank bottom is gently stirred by hand. Use micro-flowing water to flush away any contaminants floating in the water so as not to oversink the larvae and seedlings. 6.6 Timely replenishment of river mud, when the basin larvae metamorphose up to the bottom of the seedling camp, it is necessary to add some mud to the bottom of the seedlings when they change from the swimming life to the benthic crawling life. The need to supplement minerals can also avoid enemy damage. Dried Tomato,Semi Dried Tomatoes,Sun Dried Tomatoes,Dehydrating Tomatoes Ningxia Lihe Food Co., Ltd. , http://www.lihedried.com
2, choose a good pro 蚬 . Physically strong, disease-free and injury-free. The complete shell is intimacy.
3, artificial oxytocin: The selected pro 蚬 washed after Sheng in the pot or pool. Using dry stimulation, flowing water stimulation, and proper combination of chemical stimuli can induce spawning and spawning.
4, improve the fertilization rate of operation technology.
4.1 Necessary glands with well-developed selective glands, such that the excreted sperm are active and fertile.
4.2 When the urine production is properly increased, the fertility of the inbreeding stock is increased, and the sperm and eggs are arranged in a row, which increases the fertilization rate of the sperm and eggs.
4.3 After excretion of sperm and eggs, use your hands to gently stir to help the eggs and eggs more contact.
Add egg wash
100
78
twenty two
78%
Without washing liquid
100
60
40
60%
5 Operational techniques to increase hatching rate Eggs begin to split after fertilization and are split into two cells by one cell. Four-cell, eight-cell, multi-cell, mulberry, blastocyst, primitive gut, and early turf-working worms, larvae reptiles, hatch a membrane. In this process of embryonic development, it is necessary to create a suitable ecological environment for it, otherwise it will be deformed, or it will fail to develop normally. Oxygen in running water, suitable temperature control, and proper application of hatching agent can significantly increase the hatching rate. See Table 2
Table 2: Effect of hatching agent on hatching rate Number of larval larvae Excluded number Number of hatching (%)
Added 2 hours after fertilization
80
49
31
61.48
Added 5 h after fertilization
80
61
19
76.25
For adding (control group)
80
31
49
38.75
6 Raising the metamorphosis rate of larvae to raise the seedlings. After the larvae emerge from the membrane, they can perform rolling movements. After gradually removing body contaminants, they start feeding. Afterwards, it gradually turns into a double-shelled larvae, and then disappears from the basin and grows axe, cockroach, mantle, heart and intestine. It takes about 5 to 7 days to complete metamorphosis, which is a very complicated life activity. In particular, during the larval stage of replenishing larvae, the egg membrane was originally protected within the egg membrane. When the bivalves did not grow after the membrane was formed, the embryo body was completely exposed in the water, and the carelessness of the larvae was disregarded. We did a few hundred trials before we tried to make it live and become metamorphosed into basin larvae. The technical measures for cultivation were:
6.1 The water needs to be precipitated and filtered with a dense mesh sieve to filter out predator organisms and contaminants such as large animals, fish and shrimp eggs.
6.2 Frequent use of lime to kill bacteria in water;
6.3 supplement the oxygen in the cultivating tank with running water, pay attention to the temperature difference when the water is not more than 2 °C;
6.4 Adhere to feeding three times a day for the growth of larvae. See Table 3.
Table 3: Effect of bait on the metamorphosis of larvae to seedlings Metamorphosis of larvae Temperature (°C)
18 disintegration
22-24
The larvae produce a plant sap after filming
28 disintegration
22-24
5-7 complete metamorphosis into seedlings
22-24