(1) Select parent soft-shelled turtle
Selecting excellent parent soft-shelled turtle is a very important process of artificial propagation and artificial incubation. When selecting parent soft-shelled turtle, the soft-shelled turtle should be over 4 years old, preferably 6-8 years old (the age of artificial soft-shelled turtle can be halved), and the weight should be above 1 kg, preferably 2-4 kg. Soft-shelled turtle has normal appearance, bright skin, lively and healthy, no injuries and normal development. In addition, the nutritional quality of parent turtle mainly depends on the thickness and hardness of leathery skin at the posterior margin of nail. The thin and weak skin at the trailing edge is malnutrition, and the thick and slightly wrinkled skin is excellent. Soft-shelled turtles caught with hooks or forks, soft-shelled turtles with serious internal injuries and deformed soft-shelled turtles are not suitable for parents.
(2) Ratio of investment between men and women
Because turtles have the habit of not eating each other, they are more prominent in food and fighting for spouses. Moreover, if the stocking density is too high, the discharge will increase, and the water quality will easily deteriorate, which is difficult to control. Therefore, the stocking density of parent soft-shelled turtle needs a reasonable proportion. Generally, the stocking density of the parent soft-shelled turtle with an area of 1.5~2 square meters is one per 1.5 ~ 2 square meters. If warm water is adopted, the water temperature will be controlled at about 30℃ all the year round, the water quality will be fresh, and the stocking density can be appropriately increased to about 3 animals per square meter/kloc-0. The ratio of male and female stocking is generally 3 ~ 4: 1. There should not be too many males, otherwise the males will bite each other, compete with the females for food and interfere with the normal estrus mating activities of the females. Too many males will increase the cost of breeding, but if there are too few males, the fertilization rate of eggs will be reduced.
(3) Daily management of parent soft-shelled turtle
The daily management of parent soft-shelled turtle is very important, which directly affects the success or failure of artificial reproduction of parent soft-shelled turtle. In the daily management of the parent turtle, we should pay attention to writing a management diary to record the daily weather, weather, water temperature, water quality, feeding amount, feeding situation, activities of the parent turtle, whether there is any disease, etc. Doing a good management diary is helpful to sum up experience and analyze the specific situation in time, so as to continuously improve breeding technology and improve breeding level.
The water quality of the turtle pond should be clean and fresh, especially the oxygen content of the pond water should be sufficient. In order to keep the high oxygen content of the pool water, some fresh water should be injected frequently, but not too much water, and it is appropriate to change the water at about 1/5 each time. Always pay attention to the change of water temperature. The water temperature should be kept at around 30℃. Feed properly every day. The method is to record the daily feeding amount, the feeding situation of parent turtles and the remaining amount of bait, sum up the daily feeding amount, and combine the water temperature and air temperature to get a reasonable feeding amount. After each feeding, the food table should be cleaned in time to remove the residual bait left by parents. At the same time, it is necessary to keep the quiet environment of the parent turtle farm, avoid external interference and create a good environment for the parent turtle. If it is the first time to lay eggs, turtle's parents are more strict with the environment. They often have no experience in digging holes. If they are slightly disturbed when laying eggs, they will run away in a hurry, which will seriously affect the spawning effect. In addition, the water content of the sand layer in the spawning ground is also very important. In case of continuous rainy days or dry weather without rain for a long time, the water content of sand should be adjusted in time. The method is to cover the spawning ground with a shade shed to prevent rain and sun, raise the water level or splash water to increase humidity when necessary, plant some shrubs and flowers or pile up some gravel in the spawning ground to simulate the natural environment. In short, the water content of the sand in the spawning ground should be kneaded into a ball by hand, and it will be scattered when it is released.
Parents usually lay eggs at night. It should be absolutely quiet at this time, and there should be no lights or flashlights to prevent parents from being frightened. Parents can take eggs 8 hours after laying eggs, usually in the morning after laying eggs. When taking eggs, the eggs should be placed in the Xiao Qing to avoid damage. If one end of the egg is white, it means it is a fertilized egg. Otherwise, there will be no fertilized eggs. The collected fertilized eggs should be cleaned and restored as much as possible for the benefit of parents.
(4) Artificial incubation
In the process of artificial turtle breeding, artificial incubation is a central link, and the primary task of artificial turtle incubation is to select eggs and identify fertilized eggs. Turtle eggs are collected from mid-May to early August every year, and the quality of turtle eggs collected from June to July is the best. After the mother turtle lays eggs in the spawning ground, she can get turtle eggs from the sand. Because the weight and diameter of turtle eggs directly affect the quality of embryos, the larger the diameter of eggs, the heavier the eggs, and the larger the hatchlings, the higher the quality. So when you choose eggs, you should choose turtle eggs with big and heavy eggs. Collect the collected turtle eggs and leave them in the shade for about 6~ 10 hour, and a white area will appear on the surface of the eggshell, with the eggs facing upwards, which is a sign that the turtle eggs have been fertilized. Without this white area, it can't be used for artificial incubation.
The hatching of turtle eggs used in production is carried out in an incubator. The incubator should be located in a small room, and the sand facing east or south should be made into an inclined plane. There should also be escape prevention facilities, and the whole incubator should be kept at a certain temperature. In addition, a small water tank or washbasin is buried at the lower end of the slope of the sand, and the mouth of the tank is flush with the sand and filled with water. This is because the newly hatched young turtles have the habit of swimming into the water, so that they can climb into small water tanks in droves after hatching, and it is also convenient to catch the young turtles in the water tanks.
During the incubation process, temperature, humidity and water content of sand are important factors affecting the incubation rate. During incubation, the temperature is 30~32℃, the relative humidity is 80%~85%, and the water content of sand is 7%~8%, which is a reasonable set of data.
Under suitable conditions, the shell can hatch in about 40~50 days. If under some special circumstances, the young turtle has not hatched for a long time, it can be artificially hatched, and the turtle eggs can be gently knocked open with a wooden hammer to hatch smoothly. Another method is artificially induced incubation, that is, when the accumulated incubation temperature reaches 36,000℃? Hours, collect turtle eggs with completely white eggshells and put them in a washbasin or bucket filled with warm water at 20~30℃ to completely immerse the eggshells. Due to the stimulation of warm water on turtle eggs, the hatching speed of young turtles is accelerated. Generally, a large number of young turtles will hatch within a few minutes after being put into water. For example, they hatch at 30℃ for 50 days, which is 30℃×50 days× 24 hours. Hours, so it can be artificially induced to hatch after 50 days. Both naturally hatched young turtles and artificially hatched young turtles need a temporary breeding process, but it should be noted that the water temperature of hatched young turtles should be balanced and there should be no alternation between cold and hot. At the same time, naturally hatched young turtles and artificially hatched young turtles should not be mixed together, because naturally hatched young turtles are stronger and develop faster. If mixed with artificially hatched young turtles, it will easily lead to mutual competition and killing.
In addition, here is an article on "Preventive Measures for Turtle Diseases" by China Lvye-Ningbo Agricultural Economics Online:
1, to ensure the quality of seedlings: adhere to self-reproduction, self-education, and eliminate the source of infection. When purchasing turtle seedlings, you should choose the first-and second-class turtle seedlings with pure germplasm, strong physique, active individuals, large size and no injuries, and try not to import overseas turtle seedlings without inspection by the customs inspection department.
2. Reasonable stocking: According to the breeding experience, the stocking density of young turtles is generally controlled at 20-40 /m2, the stocking density of young turtles is not more than 15 /m2, the stocking density of adult turtles is 2-3 /m2, and the stocking quantity of fish, shrimp and turtles is controlled at 300-500/mu.
3. Ensure the quality of feed: The feed should be full-price compound feed produced by reputable and high-quality manufacturers. First of all, ensure that the feed is fresh and does not deteriorate, and the particle size is appropriate. The second is to control and adjust the feed rate. The daily feeding amount mainly depends on the feeding situation, water quality and temperature of soft-shelled turtle.
4. Water quality control: (1) The water in the fish pond should be slightly alkaline, the pH value should be 7.5-8.0, the salinity should be below 1.5‰, and the temperature should be relatively stable. (2) The transparency should be 30-35cm, and the water color should be yellow-green or yellow-brown. (3) Although the requirement of soft-shelled turtle for dissolved oxygen is not high, it can be kept above 4 mg/L as far as possible. (4) Water quality regulation and sediment improvement: The application of microbial preparation to cultivate water quality can improve the stability and self-purification ability of water body. Generally, beneficial microbial agents such as EM bacteria, Bacillus, nitrifying bacteria and enzyme-producing probiotics can be used to reduce the content of ammonia nitrogen and nitrite in water and effectively decompose harmful substances such as organic matter in sediment. (5) Sewage for water: Regular sewage discharge is an effective means to control water quality. Changing water is the most direct way to adjust water quality, but changing water frequently is too expensive on the one hand, and it is easy to destroy the original ecological balance on the other. Therefore, the amount of water to be changed should be determined according to the water regime.
5, the implementation of fish, shrimp, turtle, shellfish, algae, duckweed and other mixed culture, to maintain the biodiversity of water. Multi-species polyculture is an effective means of biological disease prevention and a very effective preventive method. It can overcome the drug resistance caused by long-term use of chemical drugs or antibiotics, avoid the side effects and environmental pollution, and promote the growth of various organisms. Several better polyculture models are introduced for reference:
(1) Polyculture of Carassius auratus and shrimp: interplanting 6-8kg/mu of shrimp or shrimp with eggs in turtle ponds in winter; (2) Mixed culture of fish and soft-shelled turtle: in the conventional fish pond, 50- 100 young soft-shelled turtle cultured in greenhouse was put into each mu in early June; (3) Mixed culture of soft-shelled turtle: 65,438+00-20 Siniperca chuatsi cultured in that year, or other fish species such as Pelteobagrus fulvidraco, flower (fishbone) and Xiangyun crucian carp. Put 100- 150 fish per mu in the turtle culture pond. At the same time, 150-200 kg/mu of snails can also be stocked in the turtle pond in spring.
6. Pay attention to the prevention of turtle disease. According to the characteristics of soft-shelled turtle's disease and daily observation during the growth period, it is the key to do a good job of prevention. Usually it should be disinfected once every 20-25 days. Disinfecting drugs include safety and environmental protection drugs such as quicklime, bromochlorine preparation, sodium dichloroisocyanurate and EM bacteria, which are disinfected alternately. At the same time, 1‰-2‰ vitamin C, Shikai, florfenicol, Jiedujing, EM raw dew or enzyme-producing probiotics are added to the feed regularly to enhance the immunity of soft-shelled turtles. In particular, when environmental factors such as climate and water temperature change obviously or suddenly, such as when the soft-shelled turtle in greenhouse is transferred to an outer pond for breeding, in rainy season, typhoon and rainstorm season and high temperature weather, disease prevention and water quality control should be done in time to prevent the stress response of soft-shelled turtle from increasing, leading to endocrine disorder and disease.
The above information is for reference only.