Artificial hatching technique of cultured soft-shelled turtle eggs

1. Egg collection of Trionyx sinensis

The main results are as follows: (1) the preparation work before egg collection of Chinese soft-shelled turtle should repair and arrange the spawning site in time before the parent soft-shelled turtle enters the spawning season, plug the cave, dig loose the spawning site, spread fine sand, and adjust the humidity of the sand in the spawning ground. make it hold into a ball, let go and shake it loose. During the spawning season, the spawning ground is carefully checked every morning to see if there are any signs of female soft-shelled turtle spawning. The inspection should be carried out before the sun rises and the dew evaporates. If new soil is found, and there are paw prints of the soft-shelled turtle, and the soil surface is smooth, it is the spawning nest of the female Chinese soft-shelled turtle. At this time, a small stick can be inserted next to the egg nest for subsequent digging.

(2) the utensils ready to collect soft-shelled turtle eggs include small shovels or bamboo sticks for digging, as well as special wooden boxes, plastic baskets and pots for holding eggs.

(3) before collecting soft-shelled turtle eggs, the utensils should be washed and disinfected. After the egg collector enters the spawning ground, he will dig one nest at a time according to the mark. When digging, the floating soil at the mouth of the sealed hole should be picked gently, layer by layer. When plucking the hole and enlarging the hole, be careful not to break the eggs, then pick up the eggs one by one with your thumb and index finger from the top down and place them gently in the egg collection box. When laying eggs, they should be light, firm and steady so as not to break them. When collecting eggs, you should pay attention to checking the fertilization of the eggs. The animal pole and plant are clearly visible, there are round white spots on the top of the shell, the shell is smooth and smooth, the shell color is milky white or pink, and a large and round high-quality egg is gathered together. If the outer shell of the picked egg is not round, it is an abnormal egg, it should be put into another container, do not put it randomly. If the transparent white spots can not be seen around the eggshell, it is an azoospermic egg. If the white spots of the shell are not round and irregular, and the animals and plants are extremely blurred, they are weak sperm eggs. These three kinds of eggs should be released alone and cannot be hatched together. When collecting eggs, they are usually collected the next morning for marking the morning before, but not on the same day when they are found.

two。 Hatching mode of eggs of soft-shelled turtle Trionyx sinensis

The eggs of Trionyx sinensis can be hatched not only in indoor incubator but also in constant temperature incubator.

The main results are as follows: (1) constant temperature hatching is a form of incubation in which the automatic temperature control system is used to keep the box or indoor temperature in the most suitable temperature range to promote the normal development of fertilized eggs. When hatching in small batches, electric incubators can be used instead of incubators. When hatching in large numbers, the poultry can be modified with an incubator. It can also be specially designed, processed and manufactured. Heating is the power supply, and automatic control is adopted in the temperature and humidity control system. The hatching sand table is used to hold the soft-shelled turtle eggs, and its size and specification can be designed and installed according to the space in the box. When hatching, the bottom of the hatching plate is covered with a layer of wet sand about 4 centimeters thick. The humidity of wet sandy soil should be dispersed by holding hands and shaking hands. The diameter of sand grains is about 0.5 mm. Then put the selected high-quality fertilized eggs neatly in the sand layer, and finally cover the surface of the soft-shelled turtle eggs with a layer of wet sand 2 to 3 centimeters thick. Put the incubator into the incubator, close the door, adjust the required temperature and humidity knob, turn on the power supply, and then enter the incubation state. The temperature of constant temperature hatching should be controlled at 34 ℃ ±0.5 ℃, the sand water content should be kept at 8%-12%, and the hatching rate can reach 93%. According to the principle of constant temperature hatching, the device of kerosene lamp hatching chicks can also be used to hatch soft-shelled turtle eggs. Through manual adjustment of temperature and careful operation, a better hatching effect can be achieved. When controlling the kerosene lamp incubator, the temperature should not exceed 37 ℃, otherwise the incubation will fail.

(2) the address of the hatchery should be located in the place with high and cool terrain, leeward to the sun, good drainage conditions and convenient management. The area is about 12 square meters, the direction is facing south, the height of the north wall is less than 2.5 meters, there are large glass windows on the east, south and west, and only small windows are set on the north wall. The interior of the room is hardened with cement and is equipped with drainage channels. The roof can be covered with transparent film in the shape of a saddle, or with a glass roof, or a ridged roof. There are two shallow ponds with a height of 20 cm in the inner wall for the temporary cultivation of juvenile soft-shelled turtles. In the rest of the space, a number of multi-layer incubators are set up in order to put the hatching tray in layers and carry out three-dimensional hatching. The hatching plate is generally 60 cm × 40 cm × 20 cm, and there are several drainage holes at the bottom of the plate. When hatching, lay a layer of sand 5 cm thick at the bottom of the plate, then place the selected high-quality soft-shelled turtle eggs and cover the eggs with a layer of 3-4 cm of wet sand. A small plastic basin is buried in the corner of the incubator, the mouth of which is level with the surface of the sand, and filled with clear water to provide the shell juvenile Chinese soft-shelled turtle to climb into the water-swimming activity to facilitate collection and management. Before the soft-shelled turtle eggs are hatched, the equipment in the hatchery should be checked and disinfected, the rat hole and ant hole should be plugged, and the circuit and lighting facilities should be checked. In order to ensure the smooth progress of the hatching work, an electric stove or coal stove should be provided in the hatchery for auxiliary heating in rainy and low temperature weather. If the room temperature is too high, you can open the window to cool the air convection, or turn on the exhaust fan to vent heat and moisture to let the gas flow to cool and damp. Shading can also be taken to cool down.

(3) the simple hatching bed in the open air is a special sand bed specially built for the hatching of Chinese soft-shelled turtle in the place of high terrain, dry morning sun and shelter from the wind. The area can be determined according to the number of eggs to be hatched. It is generally 2 meters long and 1 meter wide. The north wall is 1.2 meters high and the south wall is 0.6 meters high. Surrounded by brick, the upper periphery leaves a number of vents, its bottom leaves a number of water holes, the bottom is filled with gravel and coarse sand, and the surface is covered with sandy soil 10 cm thick. The surface layer is high in the north and low in the south, forming a slope. In the southern corner, a basin containing water is buried, and the mouth of the basin is flat with the surface of the sand bed. The top cover of the sand bed is covered with transparent plastic film to achieve the purpose of heat preservation and moisturizing. When hatching, roll up the plastic film, arrange the fertilized eggs from north to south, and bury them in the sand of the sand bed. When laying buried eggs, keep a distance of about 1 cm between each egg. After the egg is set, cover the top of the egg with a layer of fine sand of 3 cm to 4 cm, and insert the hatching date mark in the gap of the egg, and then cover the plastic film on the top tightly, that is, enter the incubation period.

In the process of hatching, the temperature regulation of the hatchery bed is mainly carried out by the top of the plastic film, and the heat source is mainly irradiated by sunlight. Adding electric light bulbs to replenish heat in the cover space at low temperature can also achieve the purpose of heat preservation. When the weather is normal, for the sake of heat preservation, put a layer of grass curtain on the top of the film at night. If encounter hot weather, should add a layer of shade net or branch to shade on the film top cover during the day, or uncover part of the top cover to dissipate heat. In this hatching method, juvenile soft-shelled turtles can be seen coming out of their shells one after another in about 45 days.

In the use of hatching beds, attention should be paid to the prevention of natural enemies such as rats, snakes, ants, birds and animals, as well as the adjustment of temperature and humidity.