Abstract: Selective glandular mature carp, using different hormones, different doses of oxytocin. Different stimuli were given to broiled broodstock. Different hatching methods were adopted for the collected fertilized eggs. The results showed that: broodstock breeding is the key, broodstock well-developed broodstock, as long as provide appropriate spawning conditions (spawning pool, fish nest, water), mixed with HCG + LRH-a Hormone injection can achieve the desired oxytocin effect. Different hatching methods are adopted. At a suitable water temperature (16°C-28°C), as long as the fertilized eggs can obtain sufficient dissolved oxygen, a high hatching rate can be obtained. Salmon fry seedlings are grave. After a few days of filming, they could eat each other.
Keywords squid, artificial breeding
Parasilurusasotus is a common economic fish in China. The carp is widely distributed in China, and it is an adaptable, meat-eating omnivorous fish with delicate meat, less muscle pricks, rich nutrition and high economic value. It is of great significance to study the development of this fish industry.
1 Materials and Methods
1.1 Broodstock Prenatal Cultivation
This experiment was conducted at the Dajing Reservoir fishery in Shou County in 1994-1997. The broodstock comes from Wadi Lake and local reservoirs and is caught and collected during autumn and winter. Females weigh 500-1500 grams and males 300-1000 grams. The broodstock collected were placed in a 700-square-meter fishpond to be reared, and 2 months before delivery, the loach and wild fish were fed. The fish was flushed once every two months to promote the development and maturation of the gonads. Broodstock can also be mixed in other fish ponds. Keep the water fresh.
1.2 Preparation of spawning tanks, mesh screens, fish nests, etc.
The spawning pool can be selected from the "fish" spawning pool, or the general cement pools, ponds, etc., and sterilized with bleaching powder or quicklime one week before the production. The mesh screen is made of 40 mesh and 25 mesh polyethylene nets, and is generally made into a specification of 411 meters or 221 meters. The mesh screen should be soaked in water for several days and then disinfected with malachite green or potassium permanganate. Fish nests will be rooted in willows, palms or bamboo shells. They will be tied together after 2-3 meters. Fish nests are sterilized with malachite green or potassium permanganate before use.
1.3 Male and female ratios and broodstock selection
The ratio of male to female is 1:1. In the non-reproductive season, male and female broodstock are not easily distinguished. In the reproductive season, the female body is fresh, smooth, full of shiny sensation, the abdomen is enlarged, the outline of the ovary is looming, the gonogenic hole is reddened, enlarged, rich and moist, there are radial spots around the genital hole, and a little pressure is exerted on the back of the abdomen to extrude 1 - 2 eggs, P the first hard spine trailing edge is less powerful, slightly smooth. Males showed a longer and lighter appearance. Male fish with well-developed gonads exhibited a little white semen out of the abdomen. The jagged teeth on the male P are stronger and the hand feels cut.
1.4 artificial oxytocin production:
Artificial oxytocin uses different combinations of hormones, different doses to aphrodisiac broodstock.
Injection of HCG, female 3000 ~ 2500IU/kg. Male fish 1500 to 1300 IU/kg.
Injection of HCG+LRH-a, female HCG3000IU/kg+LRH-a15ug/kg, male HCG1500IU/kg+LRH-a7ug/kg.
The dose of artificial injection fluid is not less than 1ml per female. Basically, one-time intramuscular injection was used and two injections were used for comparison.
1.5 post-employment stimulation
In order to find the best environmental conditions for broodstock spawning, different stimuli were given to the broodstock after spawning.
1 Put the broodstock gently into the spawning tank and put it into the fish nest 2-3 hours later, and stimulate it with microfluidic water.
2 Bring the broodstock into a mesh screen. The mesh screen is hung in the spawning tank in advance, then put into the fish nest and stimulated with circulating water.
3 Bring the broodstock into the spawning pool and give it a circulatory water stimulus.
4 Put the broodstock into a mesh sieve. The mesh sieve is suspended in the pond beforehand. The pond has micro-flowing water.
1.6 fertilized egg hatching method
1 The fertilized eggs adhere to the fish nest more evenly, and they are gently moved into a mesh sieve. The mesh sieve is suspended in the cement pool and the cement pool is maintained in a microfluidic state.
2 The fertilized eggs adhere to the mesh sieve more evenly, and the mesh sieve is suspended in the cement pool, and the microfluidic state is maintained.
3 The fertilized eggs adhere to the fish nest more evenly, gently put it into the mesh sieve, and suspend the mesh sieve in the pond, in a microfluidic state.
4 Put the collected fertilized eggs into the loop and incubate the looped water.
1.7 Fry cultivation
The hatching of fish fry begins on the second day and the bait is preferably rotifer, and egg yolk can also be used. After 3-5 days, young cladocera, copepods, and microzooplankton, Artemia nauplii, and leeches were bred. Facilities for fry cultivation can be compared using mesh screens, concrete tanks, and earthen ponds. The earthen pond cultivation should splash bean water one week ahead of time to cultivate palatable bait.
2 results
2.1 Hatching situation
A total of 163 broodstock-producing broodstock groups were spawned, and the spawning number was 115. The spawning rate was 71%. A total of 1.02 million eggs were obtained. The average number of eggs laid per female was 0.87 million and a total of 800,000 seedlings were obtained. The number of females with 0. The fertilization rate is 80 to 90%, the hatching rate is 90 to 95%, the estrus time is 12 to 17 hours, and the spawning effect time is 13 to 21 hours. The tolerance to hormone HCG is in the range of 2500-3000 IU/kg for females and 1300 to 1500 IU/kg for males. Spawning suitable water temperature is 16 ~ 28 °C.
2.2 Effect of hormone dosage and variety on oxytocin
1HCG dose female was 300IU/kg, male fish 1500IU/kg bred broodstock had four batches of carp 119 groups I, II, III, IV, and spawning group number was 72, the egg production rate was 60.5%, of which I, VI A total of 26 groups were approved, with 26 spawning females, spawning rate of 100%; Group II 60 groups, spawning females 32, spawning rate of 53%, due to the first batch of brooding fish before spawning The 6-square-meter small cement pool was raised for 4 days. It is speculated that the reason may be that the density of the broodstock is too high, and the dissolved oxygen is insufficient. This has caused certain changes in the gonads in the past 4 days, which has affected the smooth progress of broodstock spawning. In addition, all broodstock after puerperium is put into a spawning pool, the density is also very large, it also has an impact on their spawning. The 33rd batch of carp group 33 and 14 spawning females were spawned at 42% because the third batch of broodstock was selected from the broodstock that was spawned on May 6th and May 9th, 1994. After more than one month of cultivation, the In the case of secondary oxytocin production, it is estimated that part of the gonad's gonadal re-growth is not mature enough.
2 The dose of HCG injection was 2500 IU/kg for females and VII and VIII for males with 1300 IU/kg. There were 16 groups of broodstock, 15 spawning females, and the spawning rate was 94%.
3 Injection of HCG+LRH-a, female HCG3000IU/kg+3000IU/kg+LRH-a15ug/kg, male HCG1500IU/kg+LRH-a7ug/kg, and IV and V batches of 28 groups, spawning female fish The number is 28 and the spawning rate is 100%.
From the above it can be seen that salmon can be injected with HCG or HCG and LRH-a mixture, the injection dose is 2 to 3 times that of domestic fish. In general, the effect of injection of HCG+LRH-a mixture was best, estrus was earlier, estrus time was 12 to 15 hours, spawning was more concentrated, spawning effect was also the shortest time 13 to 18 hours, although the water temperature was biased. Low (see Table 1).
2.3 The squid began to estrus 12 to 17 hours after the hormone injection and began to lay eggs 13 to 21 hours later. This article has basically found out the time of estrus and spawning time, and has a certain guiding effect on production practice. The length of the estrus and the length of the spawning effect are mainly related to the maturity of the broodstock, the temperature of the water when elicited, and the dose and type of hormone used. In general, broodstock development is good, the water temperature during oxytocin is higher in the appropriate range, and the hormone HCG+LRH-a mixture is injected, the estrus time is shorter, and the oviposition time is shorter. In production practice, it has been observed that the eel's estrus persists for a long period of time, and spawning takes longer.
2.4 squid spawning habits
When the squid begins to estrus, the males chase the females and use the snout to "collide" with the female's abdomen or near the genital hole. After several "collisions", the females began to spawn. The male's entire body was tightly wound around the female's back abdomen. When the females discharged the eggs, the males discharged the sperms, and the male and female breds separated the water with the tails. Fertilize spermatozoa "in combination" and spread evenly. The egg and sperm of the male and female broodstock are not finished at one time, only a little bit at a time, and it takes several times to finish. The broodstock mating behavior lasts for 3 to 4 hours or even longer. When there is a fish nest, the brooding fish love to lay eggs near the fish nest, and evenly spread the eggs on the fish nest. When there is a net nest with a fish nest, the brood fish will evenly spread the eggs on the mesh sieve without a mesh sieve or a fish sieve. At the time, the eggs are placed in the water.
2.5 squid spawning time
The spawning time of salmon can be extended from the beginning of April to the end of June, and the spawning season is from late April to mid-May. Our time for brewing broodstock was from April 28 to June 20 in the late period, and we achieved good oxytocin production. Carp is suitable for oxytocin production and spawning time is longer. The appropriate water temperature for oxytocin production and spawning is 16-28°C.
2.6 squid can spawn multiple times
In the natural world, we observed that eel's spawning lasted for a long time, and its offspring often formed different groups. For example, in the Wagatu Lake Basin, more than 10 cm of eel fry could be caught during the summer and 10 cm in the autumn. Above the salmon fry, it can be inferred from this phenomenon that salmon have either a different reproductive population or can spawn multiple times. This article tested this and on June 20, 1994, the second oyster production was conducted on May 6 and May 9, 1994. The number of spawning groups was 33 and the number of spawning was 14. The spawning rate was 42% and 100,000 eggs were obtained, indicating that the squid can lay eggs several times.
2.7 relationship between post-employment stimulation and spawning
Whether or not the squid is able to lay eggs depends on the maturation of gonads and the appropriate hormonal production. There is no significant difference in the stimuli after oxytocin stimulation. Several methods of experimental design, the carp are able to successfully land eggs, II, III batch production of eggs is low, mainly gonads of the gonadal maturity changes. Appropriate spawning water, fish nests, and water flow are indispensable conditions for smooth eel production.
2.8 Relationship between hatching method and hatching rate
There is no significant correlation between hatching rate and different hatching methods. Because of the high fertilization rate of carp, in the proper temperature range, the fertilized eggs can maintain adequate dissolved oxygen, and the unfertilized eggs can be promptly removed to prevent the occurrence of watery mildew. , can get a higher hatching rate.
2.9 Hatching and Breeding
At a water temperature of 18 to 28°C, the higher the temperature, the shorter the fry hatch time. In the water temperature range of 18 to 20°C, fish hatching began to occur after about 48 hours. After 50 hours, the fish fry broke out.
Keywords squid, artificial breeding
Parasilurusasotus is a common economic fish in China. The carp is widely distributed in China, and it is an adaptable, meat-eating omnivorous fish with delicate meat, less muscle pricks, rich nutrition and high economic value. It is of great significance to study the development of this fish industry.
1 Materials and Methods
1.1 Broodstock Prenatal Cultivation
This experiment was conducted at the Dajing Reservoir fishery in Shou County in 1994-1997. The broodstock comes from Wadi Lake and local reservoirs and is caught and collected during autumn and winter. Females weigh 500-1500 grams and males 300-1000 grams. The broodstock collected were placed in a 700-square-meter fishpond to be reared, and 2 months before delivery, the loach and wild fish were fed. The fish was flushed once every two months to promote the development and maturation of the gonads. Broodstock can also be mixed in other fish ponds. Keep the water fresh.
1.2 Preparation of spawning tanks, mesh screens, fish nests, etc.
The spawning pool can be selected from the "fish" spawning pool, or the general cement pools, ponds, etc., and sterilized with bleaching powder or quicklime one week before the production. The mesh screen is made of 40 mesh and 25 mesh polyethylene nets, and is generally made into a specification of 411 meters or 221 meters. The mesh screen should be soaked in water for several days and then disinfected with malachite green or potassium permanganate. Fish nests will be rooted in willows, palms or bamboo shells. They will be tied together after 2-3 meters. Fish nests are sterilized with malachite green or potassium permanganate before use.
1.3 Male and female ratios and broodstock selection
The ratio of male to female is 1:1. In the non-reproductive season, male and female broodstock are not easily distinguished. In the reproductive season, the female body is fresh, smooth, full of shiny sensation, the abdomen is enlarged, the outline of the ovary is looming, the gonogenic hole is reddened, enlarged, rich and moist, there are radial spots around the genital hole, and a little pressure is exerted on the back of the abdomen to extrude 1 - 2 eggs, P the first hard spine trailing edge is less powerful, slightly smooth. Males showed a longer and lighter appearance. Male fish with well-developed gonads exhibited a little white semen out of the abdomen. The jagged teeth on the male P are stronger and the hand feels cut.
1.4 artificial oxytocin production:
Artificial oxytocin uses different combinations of hormones, different doses to aphrodisiac broodstock.
Injection of HCG, female 3000 ~ 2500IU/kg. Male fish 1500 to 1300 IU/kg.
Injection of HCG+LRH-a, female HCG3000IU/kg+LRH-a15ug/kg, male HCG1500IU/kg+LRH-a7ug/kg.
The dose of artificial injection fluid is not less than 1ml per female. Basically, one-time intramuscular injection was used and two injections were used for comparison.
1.5 post-employment stimulation
In order to find the best environmental conditions for broodstock spawning, different stimuli were given to the broodstock after spawning.
1 Put the broodstock gently into the spawning tank and put it into the fish nest 2-3 hours later, and stimulate it with microfluidic water.
2 Bring the broodstock into a mesh screen. The mesh screen is hung in the spawning tank in advance, then put into the fish nest and stimulated with circulating water.
3 Bring the broodstock into the spawning pool and give it a circulatory water stimulus.
4 Put the broodstock into a mesh sieve. The mesh sieve is suspended in the pond beforehand. The pond has micro-flowing water.
1.6 fertilized egg hatching method
1 The fertilized eggs adhere to the fish nest more evenly, and they are gently moved into a mesh sieve. The mesh sieve is suspended in the cement pool and the cement pool is maintained in a microfluidic state.
2 The fertilized eggs adhere to the mesh sieve more evenly, and the mesh sieve is suspended in the cement pool, and the microfluidic state is maintained.
3 The fertilized eggs adhere to the fish nest more evenly, gently put it into the mesh sieve, and suspend the mesh sieve in the pond, in a microfluidic state.
4 Put the collected fertilized eggs into the loop and incubate the looped water.
1.7 Fry cultivation
The hatching of fish fry begins on the second day and the bait is preferably rotifer, and egg yolk can also be used. After 3-5 days, young cladocera, copepods, and microzooplankton, Artemia nauplii, and leeches were bred. Facilities for fry cultivation can be compared using mesh screens, concrete tanks, and earthen ponds. The earthen pond cultivation should splash bean water one week ahead of time to cultivate palatable bait.
2 results
2.1 Hatching situation
A total of 163 broodstock-producing broodstock groups were spawned, and the spawning number was 115. The spawning rate was 71%. A total of 1.02 million eggs were obtained. The average number of eggs laid per female was 0.87 million and a total of 800,000 seedlings were obtained. The number of females with 0. The fertilization rate is 80 to 90%, the hatching rate is 90 to 95%, the estrus time is 12 to 17 hours, and the spawning effect time is 13 to 21 hours. The tolerance to hormone HCG is in the range of 2500-3000 IU/kg for females and 1300 to 1500 IU/kg for males. Spawning suitable water temperature is 16 ~ 28 °C.
2.2 Effect of hormone dosage and variety on oxytocin
1HCG dose female was 300IU/kg, male fish 1500IU/kg bred broodstock had four batches of carp 119 groups I, II, III, IV, and spawning group number was 72, the egg production rate was 60.5%, of which I, VI A total of 26 groups were approved, with 26 spawning females, spawning rate of 100%; Group II 60 groups, spawning females 32, spawning rate of 53%, due to the first batch of brooding fish before spawning The 6-square-meter small cement pool was raised for 4 days. It is speculated that the reason may be that the density of the broodstock is too high, and the dissolved oxygen is insufficient. This has caused certain changes in the gonads in the past 4 days, which has affected the smooth progress of broodstock spawning. In addition, all broodstock after puerperium is put into a spawning pool, the density is also very large, it also has an impact on their spawning. The 33rd batch of carp group 33 and 14 spawning females were spawned at 42% because the third batch of broodstock was selected from the broodstock that was spawned on May 6th and May 9th, 1994. After more than one month of cultivation, the In the case of secondary oxytocin production, it is estimated that part of the gonad's gonadal re-growth is not mature enough.
2 The dose of HCG injection was 2500 IU/kg for females and VII and VIII for males with 1300 IU/kg. There were 16 groups of broodstock, 15 spawning females, and the spawning rate was 94%.
3 Injection of HCG+LRH-a, female HCG3000IU/kg+3000IU/kg+LRH-a15ug/kg, male HCG1500IU/kg+LRH-a7ug/kg, and IV and V batches of 28 groups, spawning female fish The number is 28 and the spawning rate is 100%.
From the above it can be seen that salmon can be injected with HCG or HCG and LRH-a mixture, the injection dose is 2 to 3 times that of domestic fish. In general, the effect of injection of HCG+LRH-a mixture was best, estrus was earlier, estrus time was 12 to 15 hours, spawning was more concentrated, spawning effect was also the shortest time 13 to 18 hours, although the water temperature was biased. Low (see Table 1).
2.3 The squid began to estrus 12 to 17 hours after the hormone injection and began to lay eggs 13 to 21 hours later. This article has basically found out the time of estrus and spawning time, and has a certain guiding effect on production practice. The length of the estrus and the length of the spawning effect are mainly related to the maturity of the broodstock, the temperature of the water when elicited, and the dose and type of hormone used. In general, broodstock development is good, the water temperature during oxytocin is higher in the appropriate range, and the hormone HCG+LRH-a mixture is injected, the estrus time is shorter, and the oviposition time is shorter. In production practice, it has been observed that the eel's estrus persists for a long period of time, and spawning takes longer.
2.4 squid spawning habits
When the squid begins to estrus, the males chase the females and use the snout to "collide" with the female's abdomen or near the genital hole. After several "collisions", the females began to spawn. The male's entire body was tightly wound around the female's back abdomen. When the females discharged the eggs, the males discharged the sperms, and the male and female breds separated the water with the tails. Fertilize spermatozoa "in combination" and spread evenly. The egg and sperm of the male and female broodstock are not finished at one time, only a little bit at a time, and it takes several times to finish. The broodstock mating behavior lasts for 3 to 4 hours or even longer. When there is a fish nest, the brooding fish love to lay eggs near the fish nest, and evenly spread the eggs on the fish nest. When there is a net nest with a fish nest, the brood fish will evenly spread the eggs on the mesh sieve without a mesh sieve or a fish sieve. At the time, the eggs are placed in the water.
2.5 squid spawning time
The spawning time of salmon can be extended from the beginning of April to the end of June, and the spawning season is from late April to mid-May. Our time for brewing broodstock was from April 28 to June 20 in the late period, and we achieved good oxytocin production. Carp is suitable for oxytocin production and spawning time is longer. The appropriate water temperature for oxytocin production and spawning is 16-28°C.
2.6 squid can spawn multiple times
In the natural world, we observed that eel's spawning lasted for a long time, and its offspring often formed different groups. For example, in the Wagatu Lake Basin, more than 10 cm of eel fry could be caught during the summer and 10 cm in the autumn. Above the salmon fry, it can be inferred from this phenomenon that salmon have either a different reproductive population or can spawn multiple times. This article tested this and on June 20, 1994, the second oyster production was conducted on May 6 and May 9, 1994. The number of spawning groups was 33 and the number of spawning was 14. The spawning rate was 42% and 100,000 eggs were obtained, indicating that the squid can lay eggs several times.
2.7 relationship between post-employment stimulation and spawning
Whether or not the squid is able to lay eggs depends on the maturation of gonads and the appropriate hormonal production. There is no significant difference in the stimuli after oxytocin stimulation. Several methods of experimental design, the carp are able to successfully land eggs, II, III batch production of eggs is low, mainly gonads of the gonadal maturity changes. Appropriate spawning water, fish nests, and water flow are indispensable conditions for smooth eel production.
2.8 Relationship between hatching method and hatching rate
There is no significant correlation between hatching rate and different hatching methods. Because of the high fertilization rate of carp, in the proper temperature range, the fertilized eggs can maintain adequate dissolved oxygen, and the unfertilized eggs can be promptly removed to prevent the occurrence of watery mildew. , can get a higher hatching rate.
2.9 Hatching and Breeding
At a water temperature of 18 to 28°C, the higher the temperature, the shorter the fry hatch time. In the water temperature range of 18 to 20°C, fish hatching began to occur after about 48 hours. After 50 hours, the fish fry broke out.