Feeding techniques of mussels
First, the selection of surgical mussels
Choose mussels with intact bodies, good shell luster, fat and full axe feet, and the shell of Taiwan pearl mussels is bigger than that of producer mussels. It is best to choose 4-8 years old for pearl mussels and 4? 6 years old, according to the size, 7-1 10 cm is generally used.
Second, the operation
Operating tools (tweezers, shell opener, slicing knife, opening needle, etc.) should be prepared first. First, use the shell opener to open the shell of the production mussel and separate the two shells, then use the slicing knife to take the epidermis at the edge of the mantle, and pay attention to the uniform thickness of the epidermis, and then put it flat on the glass plate with tweezers. Wipe off the moisture on the epidermis with a sponge, then cut it into 2 mm square pieces with a slicing knife, and pour physiological saline in time to keep the pieces moist.
Put the insert on the operating frame, pry open the double shell of the pearl mussel, and insert it into the mantle with the needle for feeding and slicing. Small pieces are inserted from left to right. In order to make them contact well, they should be compacted with an open needle, so that the pearls can be more round. Generally, 3 rows can be inserted in a flower-shaped layout. After the operation is completed, it should be disinfected with disinfectant, and then it should be hung in the culture pond.
Iii. culture of pearl mussels
(A) farming methods
Pearl mussels are mostly raised by hanging and cage. Before hanging mussels in the pond, you can pile them with bamboo and wood, tie them with ropes in rows, put them in a net cage and hang them in the water. In order to hang them at the same water level, you can use plastic foam or coke bottles as floats, which is both economical and easy to use. Hanging culture methods include single hanging culture and serial culture. According to the water level, water temperature and seasonal changes, the hanging depth of pearl mussels should be adjusted in time. In winter, it should be hoisted deep (40-60 cm below the water surface), and it can be hoisted shallowly in spring and autumn (below the water surface 15-20 cm), and in summer, it should be hoisted 20-30 cm below the water surface (the water temperature is 32-34℃). The number of cages depends on the size of the cage (net cage, net clip), and it is generally appropriate that each clam can contact the bottom of the cage. Generally, there are 800 mussels per mu in the pond 1200 mussels.
(2) Management
As the saying goes, three points raise seven points in charge. During the growth of mussels after operation, their physique is weak, so they should be checked frequently. If they find dead mussels, they should be removed in time to avoid affecting the growth of other mussels. At the same time, pay attention to the position of mussels and keep them in the posture of facing the sky. In order not to affect the growth, the dirt attached to the shell should be cleaned up in time.
If the water quality of the pearl pond is thin, it should be fertilized in time. Fertilizer can be organic fertilizer or chemical fertilizer, or both. The manure of chicken, duck and bird is the best organic fertilizer, and 1% quicklime should be added before use or applied after fermentation and decomposition. Fertilizer is mainly urea and calcium superphosphate (dosage ratio: 1: 2 or1:3). The two fertilizers are mixed and sprinkled after adding water, so that the amount is less and more times. Generally, urea1kg and calcium superphosphate are used per mu. You can also pour soybean milk (feed and fertilizer). At the same time, calcium fertilizer (quicklime) is applied to keep the transparency of pool water at about 30 cm.
Feeding skills of mussels
1. Selection and cultivation of parent mussels
1. Parent mussel selection
(1) The parent mussel requires that the shell be bright, bluish-blue, complete and without defects. Abdomen? Round and round, the mussel body is strong and fat, and the shell is strong. The age of mussels is 6 ~ 8 winter, and the female mussels are best after giving birth.
(2) It is difficult to distinguish the sex of pearl mussel from the appearance, and it must be judged accurately according to the density and number of internal gill filaments. Generally, female mussels are slightly larger, with wider growth ring lines and slightly wider and thicker shells. When the mussel is opened, the gill filaments of the female mussel are arranged closely. After sexual maturity, the number of gill filaments in the outer gill flap reaches100 ~120; The arrangement of gill filaments in male mussels is sparse. After sexual maturity, the number of gill filaments in the outer gill flap is only 60 ~ 80.
2. Cultivation of parent mussels. The area of the parent mussel cultivation pond is preferably more than 2,000 square meters, the water depth is 1.5 meters, and the mud thickness at the bottom of the pond is moderate. The oxygen content of aquaculture water layer is 4.0 ~ 8.0 mg/L, the pH is 6.5 ~ 8.0, and the biomass of bait is10 ~ 20 mg/L. The water quality should not be too fat, so as to avoid the female germ cells from hypoplasia or sexual reversal due to hypoxia. If the parent mussel is cultivated in a small area of water, it must have slow flow conditions.
Generally, the ratio of male to female is 2∶ 1 (that is, 2 males 1 females 1 combination), and they are hung in the water layer end to end for sex ratio combination culture.
The cultivation of parent mussels should start in autumn, and the pond water should be injected and drained regularly, and the bait organisms should be propagated in time to promote the development and maturity of the gonads of parent mussels.
Second, fertilization and embryo development
1. Fertilization
(1) Hyriopsis cumingii is taken as an example in the fertilization season. In general, Hyriopsis cumingii has the ability to reproduce when it is 3 years old. Sexual maturity begins in May every year. At sexual maturity, the gonads of female Hyriopsis cumingii are orange in appearance, while those of male Hyriopsis cumingii are white. The spawning season is from May to July. Mature eggs are spherical; Mature sperm can swim with tail wagging under microscope. When most eggs in the reproductive nest are mature, the female mussels ovulate and fertilize. Hyriopsis cumingii lays eggs 5-8 times a year, with an amount of 400,000-500,000 eggs.
(2) Fertilization methods There are two fertilization methods: natural fertilization and induced fertilization.
① Natural fertilization: in the breeding season of mussels, the mature eggs of female mussels are discharged into the outer cavity of the body through the reproductive hole; The mature sperm of male mussel is discharged from the vas deferens to the suprabranchial cavity through the reproductive orifice, and then discharged into the external water body through the water outlet pipe. Sperm enters the female shell cavity with water and combines with the eggs to be pregnant, thus completing fertilization. The fertilized egg develops on the left and right external gill flaps of the mother clam.
② Induced insemination: The germ cells of male mussels usually mature earlier than those of female mussels. When some eggs of female mussels mature, the male mussel semen can be taken out manually, diluted with reproductive saline and injected into the mantle of female mussels, and the female mussels can be placed in a fertilization basin with a water temperature 3 ~ 5℃ higher than that of the original pool in advance for induced insemination. The sperm injected at 1 time only plays the role of inducing female mussels to ovulate, so it is necessary to inject the second diluted semen in the same way, and the sperm in this semen is just fertilized with the induced mature eggs. By inducing insemination, mussels can enter the breeding season in advance.
2. Embryo development The fertilized egg passes through the fertilized egg from cleavage? Mulberry stage? Blastocyst stage? The gastrula stage? The embryonic development process of hookworm larvae forms hookworm larvae. The whole embryonic development process usually takes 35 ~ 50 days.
Third, collecting hookworm larvae
After the metacercaria develops and matures on the outer gill flap of the mother mussel, it has sufficient silk and hooks, which can parasitize the fish and must parasitize the fish to complete the metamorphosis and become a young mussel. Therefore, when the hookworm larvae are about to come out of the membrane, they should be made of fish. Seedling picker? Collect hookworm larvae on fish.
1. Selection of fish for picking seedlings Silver carp, bighead carp, grass carp and common carp can all collect hookworm larvae, but the docile bighead carp and grass carp are the best. Each mussel needs 300 ~ 500 9.9 cm fingerlings for each seedling collection. Only by selecting excellent fish species with healthy constitution can we tolerate the parasitism of more hookworm worms.
2. Identification of the maturity of hookworm. Immature hookworm has no parasitic ability, so the maturity of hookworm must be identified. The identification method is to take out several cultured female mussels, first open the mussels with a shell opener, fix them to a certain extent with plugs, and then pick out a few hookworm larvae in the middle of the gills of mussels with a probe. If the picked hookworm larvae can adhere to each other into a chain, they are mature hookworm larvae.
3. Seedling picking method
(1) Collect seedlings indoors, inject clean fresh water with a depth of10 ~15cm into the basin, place the tested mother mussels on the bottom of the basin, then put the fish for collecting seedlings, and introduce a water pipe to make the water into running water. After several hours, it can stimulate the mother mussels to discharge hookworm.
(2) Outdoor seedling collection In the fresh water quality of rivers and lakes, you can use fish boxes to collect seedlings. A large number of seedlings are picked, which is suitable for mass production. When picking seedlings, it is necessary to change the picking points in time, and it is advisable to parasitize about 200 hookworm larvae per fish. If the number is too large, the fish picking seedlings will die. Before picking seedlings 1 day, it is necessary to pull the net to strengthen the physique of the fish, and discharge feces to avoid the pollution of hookworm larvae by the fish.
Efficacy and function of mussel
Cold in nature and sweet and salty in taste. Mussel meat: quench thirst, remove heat, detoxify and remove red eyes. Mussel juice: used for removing hemorrhoid swelling, treating hemorrhoids, rectocele and swelling and pain.
1. Mingmu
Rich in calcium, calcium increases the elasticity of the eye ball wall and prevents the occurrence and development of myopia.
Step 2 sober up
Mussel can relieve the toxicity of ethanol and excrete it quickly after drinking. Can relieve symptoms such as headache, brain swelling and blushing after drinking. Relieve the absorption of alcohol in the stomach and protect the gastric mucosa.
Step 3 clear away heat
Mussels can clear the heart, purge fire, clear away heat and vexation, and eliminate heat toxin in blood. Suitable for people who get angry easily.
Step 4 strengthen bones
Mussels are rich in calcium, which can stimulate the growth of bone matrix and bone cells and make calcium salt deposit in bone tissue. It contains trace elements such as phosphorus, which can help calcium absorption and promote bone metabolism.
5. Improve immunity
Mussels are rich in protein, and protein is the most important nutrient to maintain immune function, and it is the main component of white blood cells and antibodies.
Pearl rearing techniques of mussels
produce (a film)
1. Put the selected operation mussels into fresh water, so that the mussels can naturally eliminate the dirt in their bodies. Before the operation, clean the impurities and sludge on the shell surface.
2. Take the piece: clean the dirt on the mantle of the surgical mussel with clear water, cut off the brown marginal membrane along the abdominal edge of the mussel shell, then take out the mantle, separate the outer epidermis, immediately put it on the glass plate, and gently spread the outer epidermis upward with surgical tweezers.
3. Slicing: firstly, gently wipe off the mucus and dirt on the epidermis with foam plastic, and repair the outer epidermis into long strips with uniform width and thickness with a slicing knife, then cut the strips into small pieces of cells according to the square of 3 ~ 4 mm or 4 ~ 5 mm, and drop cold boiled water or 1? The chlortetracycline solution can keep the tablets moist and play a disinfection role.
male tab
1. Opening: Fix the cleaned mussel balls on the operating frame, use the shell opener to open the mussel shells, plug them into the end plugs, and take out the shell opener. The size of the shell opening depends on the size of the mussel. In principle, the opening of the mussel should not exceed 0.8 cm. After the plug is put in, put the mussels in a clear water basin to clean the sludge in the soft part before sending the slices.
2. Film feeding: During film feeding, aim the center of the film feeding needle at the center of the small piece to prevent irregular pearls from appearing. When picking a small piece with a crochet, the operation must be brisk, subject to the diagonal angle of the small piece. After stabbing the mantle of the mussel, you should stick to it once and not repeatedly. Small pieces should be arranged? Product? Glyph or? Plum blossom Wounds between shapes and rows should be avoided. The spacing between slices should not exceed 1 cm, generally 0.6 ~ 0.7 cm is appropriate, and the feeding depth should be 0.5 ~ 0.6 cm, which is subject to avoiding the wound. Send 40 ~ 50 pieces to each 9 ~10cm-sized mussel.
3. Round the garden: arrange the small pieces into drum-shaped protrusions outside the wound with the round tip of a round device or crochet, so as to form round pearls later.
4. Disinfection and hanging: use 1? Sterilize the wound with chlortetracycline solution, take out the cork, and drill a hole in the wing-like part of the back edge of the mussel shell to hang it.