catalogue
1. Living habits
2. Morphological characteristics
3. Distribution range
4. Breeding technology
5. Nutritional value
Living habits
habitat
The hard area of the seabed where oysters live is called oyster bed, which is located in deep or shallow seawater or salty estuary waters. Oysters live in the middle of intertidal zone.
Eating habits
Fix shellfish. Generally, it is fixed on shallow sea objects or seaside rocks, and eats and breathes by opening and closing shells. As filter-feeding organisms, they mainly feed on micro zooplankton, diatoms and organic debris. Oysters generate airflow in water by vibrating cilia on gills, water enters gills, and suspended particles in water are stuck by mucus. Cilia and tentacles on cheeks classify particles according to their size. Then the small particles are sent to the mouth, and the large particles are transported to the edge of the film and thrown out.
morphological character
Oysters have different shapes, mostly triangular, and the left shell is fixed on the rock and concave. Many tongue-shaped protrusions or spikes protrude from the end edge of the scale layer of young individuals, and the spikes of growing individuals gradually decrease. The length varies from 2 inches (5 cm) to over 12 inches (30 cm). [3] The two shells of oysters have different shapes and rough surfaces, mostly light yellow-brown with purple-brown or black-brown stripes; The middle part of the upper shell protrudes; The lower shell is attached to other objects, with large volume, quite flat and smooth edges; The inner surfaces of the two shells are white and smooth, and the front depression is deep. By counting many rings similar to the rings on the oyster shell, each ring needs to grow for one year. By counting these rings, we can know the age of oysters.
The two shells are connected at the narrower end by an elastic ligament. There is a powerful adductor muscle in the middle of the shell to resist the tension of the ligament. When the shell is slightly opened, water is introduced into the shell through the wavy motion of cilia (the water flowing through it can reach 2-3 gallons per hour) to filter microorganisms.
The body of an oyster is deep in the two shells and is surrounded by a fleshy tissue layer called the mantle. The cuff is folded into three different layers: the inner layer includes muscles; The middle layer includes two rows of sensory organs for detecting chemical and temperature changes; The outermost layer includes the secretory membrane of the shell.
distribution range
Wild oysters are distributed in tropical and temperate waters, from the high line to the water depth of 10 meters.
Oyster farms are located in the Atlantic coast of Europe and America, the Pacific coast of America, Asia, Australia, China and South Korea, and the east coast of Africa. In the United States, most oysters are cultivated in the mid-Atlantic, chesapeake bay, the Gulf of Mexico and the North Pacific.
breeding technology
Choose the sea area with stable tidal current, rich bait, calm wind and waves and water depth of more than 4m as oyster raft breeding ground. Oysters near the river should be selected near the estuary with low salinity; Oysters in Dalian Bay should be selected in high salinity waters far from the estuary. Pacific oyster and pleated oyster are in between. There are two main ways of development:
⑴ Rope-hanging culture: It is suitable for oysters with shells as a fixed base. There are two kinds of culture methods: one is to string the shells for fixing oyster seedlings with ropes, separate them with bamboo tubes of about 10cm in the middle, and hang them on a raft frame; Secondly, the shells containing oyster seedlings are clamped in the twisted seams of polyethylene ropes with a diameter of 3-3.5 cm, and every 10cm is clamped 1 shell, and hung on the floating raft. Generally, each rope is 2 ~ 3m long. You can also use rubber tires to clamp seedlings and hang them.
⑵ Cage culture: Cage culture in scallop net. Put the anchorless oyster fry or the oyster fry fixed on the shell together with the shell into the scallop cage and hang it on the floating raft. Generally, there are 667_ 65438+ 100000 oyster seedlings in raft culture. Using shells as seedling collectors, about 10000 shells can be hoisted every 667 _. Oyster seedlings are stocked in May-June and harvested at the end of the year, and the output per 667 square meters can reach more than 5,000 kilograms.
nutritive value
nutritive value
1, the zinc content of oysters per 100g is as high as 9.39mg, and men can meet the body's demand for zinc by eating one every day; In order to better supplement zinc, you can take some protein zinc zinc directly;
2. Oysters are rich in taurine, which has obvious effects of protecting liver and benefiting gallbladder, and is also a good medicine for preventing and treating intrahepatic cholestasis of pregnancy;
3. Rich trace elements and sugar are beneficial to promote the growth and development of fetus, correct anemia of pregnant women and restore physical strength;
4. Oyster is the best food for calcium supplement, and it is rich in phosphorus. Because calcium needs the help of phosphorus when it is absorbed by human body, it is beneficial to the absorption of calcium;
5. Oysters also contain vitamin B 12 which is lacking in general food. Cobalt in vitamin B 12 is an indispensable substance to prevent pernicious anemia, so oyster has the function of activating hematopoietic function;
6. There are many excellent amino acids in protein contained in oysters. These amino acids have the function of detoxification and can remove toxic substances from the body. Among them, aminoethanesulfonic acid can reduce blood cholesterol concentration, so it can prevent arteriosclerosis;
7. Oyster extract can obviously inhibit platelet aggregation, reduce the content of TXA2 in blood of patients with hyperlipidemia, promote the secretion and utilization of insulin, enhance the sensitivity of malignant tumor cells to radiation and inhibit their growth.
food therapy
Tranquilize the heart and soothe the nerves, subdue yang and replenish yin, soften hard mass, and astringent. It can be used for palpitation, insomnia, dizziness, tinnitus, scrofula, swelling, spontaneous sweating, night sweats, nocturnal emission, stomachache and pantothenic acid. Calcined oyster is astringent and can be used for spontaneous sweating, night sweats, nocturnal emission, stomachache and acid swallowing.
1, nourishing yin and suppressing yang, used for dysphoria, insomnia, dizziness, headache, tinnitus, hot flashes and night sweats caused by yin deficiency and yang hyperactivity.
2, convergence and astringency, cure hyperhidrosis, leukorrhagia and nocturnal emission.
3, soft and hard, can cure swelling, lumps, phlegm and fire.