1. Individuals are usually selected directly in shrimp ponds, and the selected broodstock individuals must be moderate. Practice has shown that females should choose individuals with a body length of 10 to 12 cm and a body weight of 20 to 30 g. This species has a large number of eggs laid, a high hatching rate, and a large number of juveniles. It is not appropriate to select 7-8cm females for broodstock. Because these individuals produce few eggs and the population is degraded, males should choose individuals with body length of 11-13cm and body weight of 30-40g. For example, if males with a body length of more than 15 cm and a body weight of more than 50 g are selected as overwinter broodstock, such individuals are likely to die during wintering, resulting in the lack of males and affecting reproduction.
2. Health and disease-free general choice of bright-colored, spotless, robust shrimp as winter broodstock. If you choose to have brown spots on shrimp shells or blackish and lean shrimps for overwintering broodstock, it will cause death, and it will be transmitted to healthy shrimps, and even cause the entire army to be annihilated, so it is not suitable for wintering. Broodstock.
3. The appendages of the appendiceal complete broodstock have sensory, feeding, defense, and exercise functions, and are directly related to mating, fertilization, and hatching. Therefore, care must be taken when selecting winter broodstock to avoid step-off and injury. Limb-defective broodstocks are susceptible to pathogens, causing death and affecting the quality and quantity of juveniles.
4. The maternal broodstock shrimp seedlings can reach sexual maturity after 4 to 5 months of breeding, and can be reared after about 6 months of wintering. Practice has proved that: 1 after the winter of females hold eggs, the fertilized eggs in the hatching process is not easy to fall off, while a winter first-born females spawn, the gonad development, early maturation, two spawning time interval is short, generally In the 20 to 30 days after childbirth, the eggs can be held again by intensive cultivation, and the eggs can be held more than 3 times during the period from March to June. However, although the number of eggs in the 2 winter females is large, the fertilized eggs can easily fall off during the incubation process. There are few hatched larvae, and the time interval for repeated egg-holding is longer and the number of reproductions is less. 3 Most of the females in winter lose their reproductive ability, and the survival rate of hatched juveniles is also low, so they are selected from the grown-up shrimps that year. Females are better.
5. The proportion of males, females, and brooders in a reasonable sex wintering pool must be reasonable. Otherwise, the reproductive and fertility rates will be affected by the imbalance of male and female ratios. The ratio of male to female broodstock is generally 4:1 or 5:1. If the ratio of male to female broodstock is 6:1, the fertilization rate is low, and the broodstock tends to have a higher mortality rate than females in wintering pools. When the broodstock enters the pool at the beginning, it is better to ensure that the ratio of male to female broodstock is 3:1.
Rice is a
finished product made after the process of rice cleaning, glutinous
rice, rice milling, and finished product finishing. The
embryo and aleurone layer of rice contain nearly 64% of rice nutrients
and more than 90% of the nutrients required by the human body. It is the
main food of the people of the South.
The carbohydrate in rice is mainly starch, and the edible rice has higher nutritional value.
Storage taboo
Rice
should not be stored at the same time as foods with high moisture such
as fish, meat, vegetables, etc., otherwise it will easily cause water to
cause mildew; rice should not be stored directly on the ground, and
should be placed on a dry, ventilated and clean pad; indoors should be
stored with high moisture content. Otherwise, it
is easy to absorb water and cause mildew; the family avoids rice stored
in the kitchen because the kitchen has high temperature and high
humidity, which has a great influence on the quality of rice.
Rice
Long Grain Rice,Basmati Rice,Glutinous Fragrant Rice,Long Grain Basmati Rice
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