Penaeus vannamei is native to Ecuador in South America. It was first imported from the Americas in 1988. It is one of the three largest cultured shrimps in the world with the highest aquaculture production. Compared with Chinese shrimp, Penaeus vannamei has a long breeding season, short larval rearing period, strong disease resistance, rapid growth, strong resistance to changes in water environment, long growth life, low requirements on feed, and survival from water. Long time, shrimp meat and other advantages. Penaeus vannamei has become one of the better substitutes for the development of shrimp culture in China. The artificial propagation technology of the shrimp is described below.
First, the choice of broodstock
Where conditions permit, we must introduce the United States without specific virus (SPF) Penaeus vannamei broodstock. The broodstock should have complete limbs, normal body color, luster, and no disease without injury. The female body should be 13 cm to 16 cm in length, 12 months to 18 months of age, and the ovaries should develop to stage III. The male body is 12 cm to 15 cm in length, and the spermatozoa are milky white and no blackening. Male to female ratio is 1:1 to 2.
Second, broodstock cultivation
In general, broodstock are first cultivated in outdoor ponds by conventional low-temperature methods for a period of time. Before propagation, they are introduced into the house to induce mating and spawning. The spawning ponds are mostly round, with a diameter of 3 to 5 meters, a water depth of 0.6 to 1.2 meters, a bottom of the pool is funnel-shaped, and the bottom of the pond is inclined toward the center with a slope of 5%.
Before entering the pool, broodstock should be bleached with 8010-6 to 10010-6 and soaked for 3 minutes to 5 minutes. The broodstock was introduced into the ripening pond from the wintering pond at a water temperature of 16°C, and rose to 20°C for 8 consecutive days at a rate of 0.5°C per day (20 o'clock to 8 o'clock in the next day, 0.3 o C, 8 o'clock in 20 o'clock, and 0.2 o C in 20 o'clock). . After two days of constant temperature, the temperature was raised to 26°C at a daily rate of 0.5°C. During cultivation, the water quality indicators were water temperature 23 °C ~ 26 °C, light 5 mg / l, pH 7.7 ~ 8.3, salinity 27 ~ 32, ammonia nitrogen three, promote cooked
The ovaries of mature females are red and broad-skinned. Males showed a pair of white spermatophores on the outside of the 5th foot base, and a special enlargement of the genital papillae from the ventral surface on the 5th foot of the foot. It was not easy to see. At this time, the sensation of gonads can be matured from 7 days to 15 days after the unilateral ocular stalks (male and female right) are removed surgically using a blanching method. Surgical broodstock is best incubated in low light (200 lux) and every 2 days to 3 days to examine the development of one-time glands. Whenever the ovary reaches the V stage, the fifth pair of males on the outside of the base of the step has a pair of white spermatozoa, which are immediately captured with a dip net and placed in the induction pool.
IV. Egg collection and hatching
After mating, females spawn at night to midnight, and check the quality of the eggs in the early morning of the next morning. Eggs are collected, washed and counted, and then hatched in hatching ponds or barrels. The incubation temperature is 29°C to 30°C. Hatched nauplii were collected by light trapping.
Feed is the material basis for larval development. Stage 1 to stage 2 juveniles were mainly spirulina powder, soymilk and egg yolk, supplemented with yeast; stage 3 zoea were mainly egg yolk and rotifers, and were regularly fed with yeast; stage 1 to stage 2 were The larvae mainly consist of egg yolk, rotifers, and shrimp slices; the third stage larvae of Artichoke are mainly Artemia nauplii, supplemented by rotifers, etc.; the larvae are mainly Artemia nauplii and are fed with a small amount of crushed Artemia worms. . Experiments have shown that the larvae have a high survival rate in the phase II larvae to the early feeding of larvae, which are fed with a combination of single-cell algae, artificial micro-feeds, and Artemia larvae. The salinity of the nursery water should be 25-30, pH 7.8-8.2, dissolved oxygen not less than 6.0 mg / liter. Virus disease and vibriosis often occur during nursery and should be fed with appropriate broad-spectrum antibiotics such as chloramphenicol (1 mg/l), oxytetracycline (0.5 to 1.0 mg/l) and furazolidone ( 0.3 mg/l ~ 0.5 mg/l) etc.
First, the choice of broodstock
Where conditions permit, we must introduce the United States without specific virus (SPF) Penaeus vannamei broodstock. The broodstock should have complete limbs, normal body color, luster, and no disease without injury. The female body should be 13 cm to 16 cm in length, 12 months to 18 months of age, and the ovaries should develop to stage III. The male body is 12 cm to 15 cm in length, and the spermatozoa are milky white and no blackening. Male to female ratio is 1:1 to 2.
Second, broodstock cultivation
In general, broodstock are first cultivated in outdoor ponds by conventional low-temperature methods for a period of time. Before propagation, they are introduced into the house to induce mating and spawning. The spawning ponds are mostly round, with a diameter of 3 to 5 meters, a water depth of 0.6 to 1.2 meters, a bottom of the pool is funnel-shaped, and the bottom of the pond is inclined toward the center with a slope of 5%.
Before entering the pool, broodstock should be bleached with 8010-6 to 10010-6 and soaked for 3 minutes to 5 minutes. The broodstock was introduced into the ripening pond from the wintering pond at a water temperature of 16°C, and rose to 20°C for 8 consecutive days at a rate of 0.5°C per day (20 o'clock to 8 o'clock in the next day, 0.3 o C, 8 o'clock in 20 o'clock, and 0.2 o C in 20 o'clock). . After two days of constant temperature, the temperature was raised to 26°C at a daily rate of 0.5°C. During cultivation, the water quality indicators were water temperature 23 °C ~ 26 °C, light 5 mg / l, pH 7.7 ~ 8.3, salinity 27 ~ 32, ammonia nitrogen three, promote cooked
The ovaries of mature females are red and broad-skinned. Males showed a pair of white spermatophores on the outside of the 5th foot base, and a special enlargement of the genital papillae from the ventral surface on the 5th foot of the foot. It was not easy to see. At this time, the sensation of gonads can be matured from 7 days to 15 days after the unilateral ocular stalks (male and female right) are removed surgically using a blanching method. Surgical broodstock is best incubated in low light (200 lux) and every 2 days to 3 days to examine the development of one-time glands. Whenever the ovary reaches the V stage, the fifth pair of males on the outside of the base of the step has a pair of white spermatozoa, which are immediately captured with a dip net and placed in the induction pool.
IV. Egg collection and hatching
After mating, females spawn at night to midnight, and check the quality of the eggs in the early morning of the next morning. Eggs are collected, washed and counted, and then hatched in hatching ponds or barrels. The incubation temperature is 29°C to 30°C. Hatched nauplii were collected by light trapping.
Feed is the material basis for larval development. Stage 1 to stage 2 juveniles were mainly spirulina powder, soymilk and egg yolk, supplemented with yeast; stage 3 zoea were mainly egg yolk and rotifers, and were regularly fed with yeast; stage 1 to stage 2 were The larvae mainly consist of egg yolk, rotifers, and shrimp slices; the third stage larvae of Artichoke are mainly Artemia nauplii, supplemented by rotifers, etc.; the larvae are mainly Artemia nauplii and are fed with a small amount of crushed Artemia worms. . Experiments have shown that the larvae have a high survival rate in the phase II larvae to the early feeding of larvae, which are fed with a combination of single-cell algae, artificial micro-feeds, and Artemia larvae. The salinity of the nursery water should be 25-30, pH 7.8-8.2, dissolved oxygen not less than 6.0 mg / liter. Virus disease and vibriosis often occur during nursery and should be fed with appropriate broad-spectrum antibiotics such as chloramphenicol (1 mg/l), oxytetracycline (0.5 to 1.0 mg/l) and furazolidone ( 0.3 mg/l ~ 0.5 mg/l) etc.
PECIFICATION
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