Technical points of artificial breeding of yellow seedlings
2018-05-25 01:43:23
First, intimacy choice and training. The species used for breeding are required to be physically strong, swim and lively. The body color should be thick black, yellow brown or black flowers, and greenish brown. Scutellaria baicalensis has sexual transformation characteristics. 1 Astragalus membranaceus is basically female in winter and 2 winter, and the male ratio is gradually increased after spawning in 2 winters. It is basically a male body until 6 winters. In the non-spawning season, it is difficult to identify males and females, generally 37-50 cm in length and 75-200 g in body weight.
Intimate stocking density is 9-10 per square meter. When breeding, male to female ratio is better than 2:1 to 3:1. The intimacy training pool is about 3 square meters, water depth is 25 centimeters, there are plenty of irregular caves in the pond wall, aquatic species such as water lilies in the pond (about 1/4 pond area), which is used by the eel to avoid light and concealment. The feed is mainly live maggots, fly maggots, oyster meats, or snail meats. The oyster meat and snail meat remove the crushed shells and big armor. The feed amount is 2.5% to 8% of the fish's body weight every day. It is fed once in the evening. . Management should remove the residual bait in time and add new water.
Second, oxytocin production. Under normal circumstances, such measures as inflating, increasing the amount of water exchange, adjusting the breeding density, and providing high-quality bait, etc., can be used for the spontaneous production of the parents. Subjects can be injected LRH-A at one time, 10 micrograms/50 grams of body weight at females, and 15 to 25 micrograms per tail at males. Males and females are given intrapleural injections 24 hours earlier than females. When injected, the depth should not exceed 0.5 cm and the injection volume should not exceed 1 ml. After injecting into the concrete pool or cage, raise the depth of water by 20-30 centimeters, change the water once a day, the water temperature is 25°C, and after 36 hours, touch the stomach of the female and feel the eggs free. insemination.
Third, artificial insemination. (1) Intimate choice. Females are selected to be about 30 cm in length and 150-250 g in body weight. Mature females have a spindle-shaped enlargement of the abdomen. Individuals with smaller mature females have a transparent zone on the abdomen. Egg outlines are visible outside the body and are touched by hand. The abdomen feels soft and elastic, and the genital hole is red and swollen. Males weigh 200-250 grams, the abdomen is small, there are blood line markings on the ventral surface, and the genital hole is red and swollen. (2) Operational points for artificial insemination. Remove the female ovulation that begins to ovulate, hold the front with a dry towel on one hand, and squeeze the abdomen with the other hand from front to back. However, most clogs will have a cloacal plugging phenomenon. At this time, small scissors can be used to cut 0.5-1 cm into the cloaca, and then the eggs can be extruded for 3-5 consecutive times. Glass containers or porcelain pots can be used for ovulation containers. Immediately kill the male foal and take out the mature testis. Cut the testis with scissors and put it into the egg-squeezing container. Stir thoroughly. Then add 200 ml of Renji solution for 5 minutes. Add clean water to filter the testis and bloodstain. , Incubation into the incubator in still water.
Fourth, temperature control incubation. The depth of incubation is about 10 centimeters. It is advisable to constantly change the water midway, but the temperature difference should not exceed 4°C. Embryonic oxygen consumption is different at different stages. The more oxygen consumed in the first stage, the more aerators should be used for proper oxygenation. The time required for incubation is closely related to the water temperature. For example, at 288 hours at 22°C, only 26 hours at 26°C. It takes 134 hours and it is even shorter when the water temperature reaches 30°C.
Fifth, seedling cultivation. It is advisable to use a concrete pool with a depth of 30-40 cm. The upper edge should be more than 20 cm above the surface of the water. The bottom of the tank should be at least 20 cm thick. In the pond, a small amount of manure water is applied to cultivate silkworms, and water hyacinth and other aquatic plants rich in roots should be stocked. The fry stocking density is about 200 per square meter. The open bait is mainly silkworm, and can also be fed with zooplankton or fish sauce and egg yolk. The last thing to add is: The body length of the seedlings is only 1.1-1.2 cm long when they are out of the membrane. The bottom of the lateral pool is based on the yolk sac. After 5 days from the membrane, the egg yolks were fed (screened with 50 mesh). After 3 days, the rotifers were fed. After 1 week, the silkworms were fed with water and the leeches were fed. After 10 days, the fish larvae were fed and the body length was 20-25 days after emergence. 5 centimeters, began to put artificial feed, and feeding mash. After 2 months, body length 7-10 cm, can be kept in separate ponds. Seedlings are cultured for 120 days and their body length can reach 8-13 cm. There should be a certain silt layer at the bottom of the nursery pond. If there is no microfluidic condition, the water can be changed once every 2-4 days, and each time the water is changed by 1/3— 1/2, temperature difference when changing water should not exceed 3 °C. Avoid polyculture, in order to avoid self-mutilation.
Six, disease prevention and treatment. Seedlings rarely develop, but if the environment is poor, it is prone to brucellosis, coma, etc. The occurrence of water mildew when the Astragalus in 3% -4% saline bath 3 - 4 minutes to eliminate, the shade can be used in high temperature season, ground water change and other methods to prevent coma.
Intimate stocking density is 9-10 per square meter. When breeding, male to female ratio is better than 2:1 to 3:1. The intimacy training pool is about 3 square meters, water depth is 25 centimeters, there are plenty of irregular caves in the pond wall, aquatic species such as water lilies in the pond (about 1/4 pond area), which is used by the eel to avoid light and concealment. The feed is mainly live maggots, fly maggots, oyster meats, or snail meats. The oyster meat and snail meat remove the crushed shells and big armor. The feed amount is 2.5% to 8% of the fish's body weight every day. It is fed once in the evening. . Management should remove the residual bait in time and add new water.
Second, oxytocin production. Under normal circumstances, such measures as inflating, increasing the amount of water exchange, adjusting the breeding density, and providing high-quality bait, etc., can be used for the spontaneous production of the parents. Subjects can be injected LRH-A at one time, 10 micrograms/50 grams of body weight at females, and 15 to 25 micrograms per tail at males. Males and females are given intrapleural injections 24 hours earlier than females. When injected, the depth should not exceed 0.5 cm and the injection volume should not exceed 1 ml. After injecting into the concrete pool or cage, raise the depth of water by 20-30 centimeters, change the water once a day, the water temperature is 25°C, and after 36 hours, touch the stomach of the female and feel the eggs free. insemination.
Third, artificial insemination. (1) Intimate choice. Females are selected to be about 30 cm in length and 150-250 g in body weight. Mature females have a spindle-shaped enlargement of the abdomen. Individuals with smaller mature females have a transparent zone on the abdomen. Egg outlines are visible outside the body and are touched by hand. The abdomen feels soft and elastic, and the genital hole is red and swollen. Males weigh 200-250 grams, the abdomen is small, there are blood line markings on the ventral surface, and the genital hole is red and swollen. (2) Operational points for artificial insemination. Remove the female ovulation that begins to ovulate, hold the front with a dry towel on one hand, and squeeze the abdomen with the other hand from front to back. However, most clogs will have a cloacal plugging phenomenon. At this time, small scissors can be used to cut 0.5-1 cm into the cloaca, and then the eggs can be extruded for 3-5 consecutive times. Glass containers or porcelain pots can be used for ovulation containers. Immediately kill the male foal and take out the mature testis. Cut the testis with scissors and put it into the egg-squeezing container. Stir thoroughly. Then add 200 ml of Renji solution for 5 minutes. Add clean water to filter the testis and bloodstain. , Incubation into the incubator in still water.
Fourth, temperature control incubation. The depth of incubation is about 10 centimeters. It is advisable to constantly change the water midway, but the temperature difference should not exceed 4°C. Embryonic oxygen consumption is different at different stages. The more oxygen consumed in the first stage, the more aerators should be used for proper oxygenation. The time required for incubation is closely related to the water temperature. For example, at 288 hours at 22°C, only 26 hours at 26°C. It takes 134 hours and it is even shorter when the water temperature reaches 30°C.
Fifth, seedling cultivation. It is advisable to use a concrete pool with a depth of 30-40 cm. The upper edge should be more than 20 cm above the surface of the water. The bottom of the tank should be at least 20 cm thick. In the pond, a small amount of manure water is applied to cultivate silkworms, and water hyacinth and other aquatic plants rich in roots should be stocked. The fry stocking density is about 200 per square meter. The open bait is mainly silkworm, and can also be fed with zooplankton or fish sauce and egg yolk. The last thing to add is: The body length of the seedlings is only 1.1-1.2 cm long when they are out of the membrane. The bottom of the lateral pool is based on the yolk sac. After 5 days from the membrane, the egg yolks were fed (screened with 50 mesh). After 3 days, the rotifers were fed. After 1 week, the silkworms were fed with water and the leeches were fed. After 10 days, the fish larvae were fed and the body length was 20-25 days after emergence. 5 centimeters, began to put artificial feed, and feeding mash. After 2 months, body length 7-10 cm, can be kept in separate ponds. Seedlings are cultured for 120 days and their body length can reach 8-13 cm. There should be a certain silt layer at the bottom of the nursery pond. If there is no microfluidic condition, the water can be changed once every 2-4 days, and each time the water is changed by 1/3— 1/2, temperature difference when changing water should not exceed 3 °C. Avoid polyculture, in order to avoid self-mutilation.
Six, disease prevention and treatment. Seedlings rarely develop, but if the environment is poor, it is prone to brucellosis, coma, etc. The occurrence of water mildew when the Astragalus in 3% -4% saline bath 3 - 4 minutes to eliminate, the shade can be used in high temperature season, ground water change and other methods to prevent coma.