The new technology of raising crabs and earthen ponds

First, the preparation of pro-crab artificial reproduction of crab seedlings, must first have enough brooding crabs. At present, it is mainly achieved through two approaches: one is the capture of natural pregnant crabs from the sea, and the other is the placement of matured pro-crabs into the seawater environment to promote their mating. The former utilizes natural resources and can reduce costs in nursery production. However, since the natural resources of river crabs have been reduced year by year, the adoption of the latter is more proactive and secure.

1. Selecting the pro crabs and keeping the pro crabs should choose to keep the green crabs, and they should be strong and lively, with a weight of 100 grams or more. The ratio of male to female is 2 to 1. The election time is generally before and after the beginning of winter (in early November of the Gregorian calendar, according to the specific circumstances of the local crabs). When you choose to keep crabs, sometimes you may not be able to collect them all at once. Cage farming can be used. Place the pro crabs in bamboo cages and hang them in a river or pond with a certain amount of water. The bamboo cage is drum-shaped, about 40 cm high, with a cage waist diameter of 60 cm and a bottom diameter of 40 cm. The holes in the cage are such that the crab cannot escape. When raising them, add 20 to 25 crabs per cage. To separate male and female. During the holding period, according to the needs of feeding crabs, feed such as quail meat, miscellaneous fish, and salted fish and vegetables are fed. This method can be used for a longer period of time.

2. After the crabs have been collected and transported, the crab cage can be used as a long-distance transportation packaging equipment. The cage is first lined with pouches, and the crabs are then taken into the pouches. The crabs are laid flat and the pouches are firmly placed so that the crabs cannot be grasped. To reduce the loss of crab feet and the consumption of crab body power. Before the vehicle is started, soak the water in the packed crab cage for a few minutes to keep some water in the cavity so that it can be breathed. At the same time, the pro-crabs are also kept in a humid environment. During transportation, wind, sun and rain should not be prevented, nor should it be placed in a ventilated or warm cabin. This kind of transportation, after 2 to 3 days, the survival rate can reach more than 90%.

3. After the rearing crabs have been collected, in order to ensure that the pro-crab overwintering and mating spawning, the pro-crabs that have been collected and transported should be carefully reared in a freshwater pond. The measures can be used in free-range and cage culture.

(1) Free-range farming: The common earth pond can be used for free-range farming. The area of ​​the pond is about 1 mu, and the depth of water is more than 1 meter. It can free up 250 to 500 kilograms of pro-crab. Before clearing crabs, clear the pond first. Each kilogram can be sterilized with quicklime 75kg or formalin 6kg. The pro-crab pool must be equipped with anti-fighting facilities, especially at the entrance and exit. Anti-evacuation nets can be used with dense mesh wire mesh, mesh size so that the pro-crab can not escape. Anti-escape around the pond usually consists of a bamboo strip with a height of 1 meter and a cover net, or a concrete factory wall with a “factory” shaped pressure opening. The width of the mouth is about 20 centimeters. Climb to escape. Free-range pro crabs are best for males and females.

(2) Cage culture: The same method of cage rearing as in the case of parent crabs. However, in the long-term breeding of this method, it is easy to cause step-foot disability due to mutual clamping of the pro-crab in the cage, and the feeding management is also troublesome. Therefore, in addition to test needs or special circumstances, many have not been adopted.

(3) Crabs in cement ponds: If there are ready-made cements and other facilities, and after the measures to prevent escape, they can also be used to raise crabs. 5-6 cm soil or sand can be laid at the bottom of the pool. A layer of nylon film is applied to the wall of the concrete pool to prevent the crab claws from being worn. Putting bricks, blocks, and other stones into the artificial crab caves can create some adaptations to crab life. Habitat ecological conditions. Crabs in cement ponds are suitable for density of 3 to 4 eggs per square meter and should not exceed 8 eggs. The density is too high and the survival rate is low.

4. The management work in management and feeding mainly includes three aspects: feeding, changing water and preventing flight. There are many types of feedstuffs, including saltwater, small junk fish, clam meat, rice dumplings, cocoon, rice, barley, vegetables, hawthorn, and animal carcasses. Feeding quantity can be customized according to the situation to meet the needs as much as possible. If you do not feed enough, so that the pro-crab starvation, will affect the smooth winter, increase mortality. According to experimental statistics, from the end of November each year to the end of April of the following year, during the five-month keeping period of the Ministry of Foreign Trade and Economic Cooperation, about 1 to 2 kg of salted bellied fish per kg of pro-crab should be fed. 0.5% to 1% of the weight of the pro crabs. Usually after 4 pm feeding, chopped octopus, vegetables and other feed can be sprinkled on the side of the pool, and cages are kept in cages. In order to keep the water fresh, it takes 3-4 days for a water exchange. In order to prevent crabs from fleeing, you must check every day whether there is any hole in the bamboo foil or whether there is crab entangled on the net. In addition, the activity and feeding of pro-crabs are closely related to the water temperature. Below 6°C, activities and feeding are greatly reduced. Therefore, measures such as feeding and changing water should be relatively reduced.

5. Pro-crab production to promote production each year from early December to mid-March next year, is the crab mating spawning period. However, as far as artificial breeding is concerned, the optimum time for pro-crab production in Jiangsu and Zhejiang provinces should be selected in the middle and early March. During this period, the overwintering and pro-crab crabs will be placed in a seawater pond with a salinity of 8 to 33 inches in proportions of 3 to 1 to 2 to 1 male and females, all of which can be successfully mated and spawned. The second day after the sea water promotes production, it is able to see the egg-raising individual. After one week, the rate of ovulation can reach 70%-80%. After half a month, the female crab can basically be pregnant. At that time, the male crabs can be taken out and handled separately so that the male crabs will not chase the female crabs to hug the mating, causing the female crabs to suffer casualties. If a cement pool is used as a propulsion pool, the density and water temperature of the pro-crab must be observed. If the density is too high, female crabs will be miscarried and the eggs will not adhere to the temperature of the hairs of the abdomen of the female crab. The water temperature must be controlled above 10°C. The water temperature is too low and the vigor of the female crab is weakened, which is not conducive to the completion of fertilized egg adhesion to the bristles. Auxiliary movements also cause abortions. In addition, the pool is best covered with mud.

Experience has shown that it is not advisable to use pro-crabs in the sea in the autumn or winter of the year to promote production. In the freshwater, wintering will be used to artificially increase the yield before the convulsions in early March of the following year, so that the first stage of juvenile larvae will hatch at about the end of mid-April and the beginning of the next month. Avoid cold waves and reduce deaths.

Shilu Huanglian is mainly produced in the primeval forest area of Dafengpu, Huangshui National Forest Park, Huangshui Town, Shizhu County. The unique climate, water quality and soil conditions in this area are the best growth areas for Shiluo Huanglian. In 1991, the Ministry of Agriculture Investment in the establishment of the National Yellow River Huangpi GAP demonstration base, the town has also established China's largest Coptis market. Natural plant Raw materials Agricultural products are not any additives. Traditional Huanglian kang, baking with firewood, drying, hair removal with bamboo cage trough, the species are hand-selected, remove the impurities and minced, relatively clean.

Natural Coptis

Natural Coptis,Wild Ya Lian,Natural Coptis Powder,Natural Coptis Chinensis Extract

Chongqing Taisun Pharmaceutical Co., Ltd. , https://www.taisuncoptis.com