CATDOLL : CATDOLL: Crab farming technology and management, what conditions are needed for farming

1. Crab farming technology and management, what conditions are required for farming

If you want to raise crabs, you first need to build a pond of appropriate size. The water in the pond must be clean and hygienic enough. There must also be aquatic plants in the pond, but the number of aquatic plants cannot be too many. At the same time, you need to prepare an oxygenator to supply oxygen to the crabs, and you also need to prepare an anti-escape device. When choosing crab seedlings, do not choose those with injuries or difficulty breathing.

1. Crab farming technology and management

1. Crab breeding technology

(1) First, you need to build a pond of appropriate size. The water in the pond must be clean and sanitary, and there must be enough sunlight around it. The water in the pond should not be too deep, generally 50cm deep, and the height of the pond should be above 1m.

(2) There must be water plants in the pond where crabs are raised, because water plants can not only produce oxygen, but also have a certain effect on purifying water quality. The amount of water plants should be determined according to the changes in weather and climate. In summer, the amount of water plants can be more, and in other seasons, the amount of water plants should be reduced.

(3) When breeding crabs, you can prepare an aerator to provide oxygen to the crabs. If there is not enough oxygen in the water, the crabs will suffocate to death. You also need to prepare some anti-escape devices and water filling and drainage systems.

(4) You need to choose high-quality crab seedlings. Do not choose crab seedlings with injuries or difficulty breathing.

(5) Before putting crab seedlings in, you can disinfect the pond with quicklime. Generally, the amount used per mu is 70 kg. Half a month after disinfection with quicklime, crab seedlings can be put in. In addition, you can place the crab seedlings in a corner of the pond to let them adapt to the pond environment before putting them in.

(6) Generally, crab fry can be released in the spring. At the same time, they need to be fed with feed, but the amount of feed should not be too much. When the crabs are slightly larger, they can be fed with an appropriate amount of meat feed.

2. How to manage crabs

(1) When breeding crabs, it is necessary to observe the behavior of the crabs. If any crabs are found to be behaving abnormally, they need to be isolated in time.

(2) You need to change the water frequently, but not all at once. Generally, you should change about 40% of the water first. When changing the water for crabs, be careful not to allow the water temperature and water level to fluctuate greatly.

2. What conditions are required for crab farming?

1. The place for breeding crabs must be quiet, sheltered from the wind and facing the sun, and transportation must be convenient.

2. The breeding site should have sufficient water resources, good water quality and convenient irrigation and drainage. The silt at the bottom of the pond should not exceed 5cm.

3. After selecting a site, you need to go to the relevant department to apply for the corresponding breeding certificate.

4. When raising crabs, you need to find a good sales channel in advance.

2. How to raise small crab seedlings?

I don't know what kind of crab you are talking about. Here are some feeding methods for blue crabs. I hope it will be helpful to you.

1. Baiting technology

(1) Bait types Blue crabs are carnivorous crabs, so carnivorous baits should be used as the main feed, supplemented by plant baits. Commonly used baits include small low-value shellfish such as red-fleshed blue clams, Xun's muscle clams, duck-billed clams, small hairy clams, short-toothed clams, freshwater river clams, freshwater snails, as well as small fish, shrimps, crabs, etc. Some artificial baits for blue crabs can also be fed. There are many types of edible baits, which can be selected according to the actual local resource conditions. As long as the bait is non-toxic and harmless and the blue crabs like to forage for cheap baits, they can be used as a bait source to ensure supply. However, the bait must be fresh, and moldy and spoiled baits must not be fed, otherwise it will seriously affect the healthy growth of blue crabs.

(2) Feeding ratio The amount of feed during the breeding period should be flexibly controlled according to the water temperature, tide, water quality and the activity of blue crabs. For example, blue crabs feed vigorously when the water temperature is above 15℃, reaching the peak at 26℃. If the water temperature is higher than 30℃ or lower than 13℃, their food intake will be significantly reduced. For example, the water temperature in the coastal areas of Zhejiang (Wenzhou and Taizhou) is more suitable from May to June and September to October, and the food intake of blue crabs will increase, so more feed should be given; the water temperature is relatively high during the high temperature period from July to August, and the water temperature is significantly lower before May and after October, and the food intake of blue crabs will decrease, so less feed should be given.

During high tides or rising tides, blue crabs eat more, and less during low tides or after ebb tides; after water is replaced during high tides, the water quality is good and the feeding rate is enhanced, so the amount of feed can be increased by 1 times compared to usual times; if it rains a lot, the pond water is turbid or the weather is hot and humid, the food intake will decrease, so the amount of feed should be reduced appropriately; in cold weather, when the water temperature drops to around 10℃, blue crabs are less active or not active, and forage for food less or not at all, so you should pay attention to feeding less or no feed.

The amount of food consumed by blue crabs increases gradually as they grow, but the ratio of daily food intake to their body weight decreases as their body weight increases. The general relationship and percentage between the amount of food fed and the size of blue crabs is as follows: when the crab carapace is 3 to 4 cm wide, the daily amount of food fed accounts for about 30% of their body weight; when the crab carapace is 5 to 6 cm wide, the daily amount of food fed accounts for about 20% of their body weight; when the crab carapace is 7 to 8 cm, the daily amount of food fed accounts for 15%; when the crab carapace is 9 to 10 cm, the daily amount of food fed accounts for 10% to 12%; and when the crab carapace is 11 cm wide, the daily amount of food fed accounts for 5% to 8% of their body weight.

(3) Feeding method: Feed should be evenly distributed around the crab pond, not in the center of the pond. If conditions permit, it is best to set up several feeding tables around the pond to better control the daily feed amount. According to the life habits of blue crabs, which hide during the day and come out at night to forage, one-third of the daily feed amount can be fed in the early morning and two-thirds in the evening. In August, the northwest wind rises (referring to the lunar calendar), and the temperature difference between the first and second half of the night widens. Blue crabs tend to be irritable and easy to escape after midnight. It is best to add an appropriate amount of feed in the first half of the night, which can prevent blue crabs from escaping and reduce their killing. In short, feeding should be based on water quality conditions, weather changes, crab growth and molting conditions, and other factors to flexibly control the daily feed amount.

3. Crab seedling breeding technology

It is easy to raise crabs. Just buy a fish tank, put some sand in it, and build a high stand so that it can bask in the sun. As for food! You can feed it a small amount of grains, but the most ideal thing is millet and glutinous rice. You can also let it eat meat occasionally, such as a small fish or a grasshopper.

4. I would like to ask about the specific method of raising hairy crab seedlings. Please support me! Thank you

(1) Water quality

The breeding of hairy crabs is done by releasing them into the wild, so we chose Xingfu Reservoir in Yingshan County to implement this breeding plan. This is mainly because Xingfu Reservoir is the main drinking water source for the city of Yingshan County. Under the government's high standards for drinking water sources, the water quality of the water source is protected to a certain extent. In addition, under the principle of ensuring the amount of drinking water, the water quantity is also relatively guaranteed!

(2) Environmental factors

The hairy crabs are farmed by letting them grow freely, so the breeding environment must be selected with high standards. The natural conditions of Xingfu Reservoir are very suitable in all aspects, including climate change, year-round temperature, natural disasters (floods), environmental pollution, such as air, noise, pesticides, and traffic conditions. It is the first choice for hairy crab breeding!

In addition! Because Director Yang has many years of experience in reservoir management and has a unique understanding and control of all aspects of the reservoir environment, of course, large-scale aquaculture in reservoirs requires particularly high anti-theft requirements. After a year of trial aquaculture experience and understanding, the people of Qingshui Township, where Xingfu Reservoir is located, are conservative and there are few thefts among the people. Therefore, vigorously developing the hairy crab aquaculture business here can achieve twice the result with half the effort!

2. Hardware

The hard equipment area is divided into a breeding area and a management area, all of which utilize the existing reservoir area and equipment of Xingfu Reservoir!

(1) Breeding area

The breeding area uses nearly 4,000 acres of water surface in the Xingfu Reservoir as the breeding area. After a year of experience, the shallow water area of ​​the entire reservoir is very suitable for the breeding of hairy crabs. The reservoir has abundant aquatic plants, snails, wild fish and other natural baits. The crabs produced by using these natural baits are large in size, with green shells (commonly known as green backs), white bellies, and golden legs, which are the characteristics of hairy crabs. It can reduce the breeding cost and does not require the use of drugs. Therefore, it is the best policy to make good use of this great natural resource!

(2) Management area

Management area is divided into

1) Office, reception room and cadres' dormitory.

2) Fishery guardhouse on the surface of the reservoir.

3) Motor boats, patrol vessels, etc.

3. Introduction to the process and technology of hairy crab farming

1. Breeding process

Purchase crab seedlings (50-70 crabs per pound) in Jiangsu before March every year --- Stock the entire reservoir area --- Patrolmen feed a small amount of wild fish to supplement the bait before dark every day --- Prepare to release crabs in ground traps one month before the Mid-Autumn Festival every year!

2. Brief introduction to the company’s breeding technology.

2-1 Hydrological conditions

Hydrological conditions are the most important factor in determining the success or failure of aquaculture and the amount of profit. Strict selection of water source conditions and quality is the first step to successful aquaculture.

2-2 Employee Conditions and Management

The aquaculture industry is a typical labor-intensive industry. The process of crab farming from the selection of crab seedlings to the sale and transportation of adult crabs takes at least 7 months and at most 12 months. The process is long and requires employees to go all out and manage every minute. In addition, most large-scale aquaculture areas are located in remote areas. The aquaculture area is too large and the location is remote. If an emergency occurs, it will be difficult to support. If you are not careful, the loss will be huge. In addition to a strict and good management system and aquaculture technology, the quality of employees is another important key to success. The conditions are as follows:

<1> Physically fit, preferably with background and experience in aquaculture.

<2> Have interest and enthusiasm in aquaculture.

<3> Careful, patient, hardworking and able to endure hardships.

<4> Good character, integrity, loyalty, and good work cooperation.

<5> You must stay at the fishing ground permanently except for scheduled vacations.

Since hairy crabs are still a popular crab species in China, and have not been replaced by other crab species in China, Hong Kong, Macao, Taiwan, and even other countries in the world for more than ten years, it can be seen that they have unlimited prospects. Therefore, the cultivation of talents and the formulation of reward and punishment measures are important foundations for future development. Otherwise, no matter how good the species, how advanced the technology, how good the system, and how broad the market are, they cannot be promoted without the help of "talents".

2-3 Types of feed

Xingfu Reservoir is blessed with unique natural resources. Feed expenditure accounts for 80% to 90% of the total breeding cost, which is a huge proportion. Making good use of the reservoir's natural bait is the key to profitability.

Types of feed: divided into <1> animal bait, <2> plant bait.

<1> Animal bait: wild fish, snails, river clams, etc. from the reservoir.

<2> Plant bait: aquatic plants, melons, fruits and vegetables, barley, wheat, etc.

In order to reduce the cost and quality of breeding as much as possible, we try to use the original natural bait in the reservoir as much as possible during the breeding process!

Feeding technology instructions

Chinese hairy crabs are omnivorous crabs, so the following should be noted when feeding them:

1) Feed crabs at regular intervals and in fixed quantities according to the size of the crab population and the stocking density, and record the situation daily.

2) Manage according to the manual and observe the growth of crabs, eating habits and changes in crab bodies at any time.

3) All wild fish, snails, wheat, etc. fed to the fish must be fresh. When any problems are found, the management staff must be notified immediately so that emergency response can be taken.

In short, there are actually many on-site conditions in crab farming, which cannot be described in detail one by one, but as long as scientific, enterprise-oriented, data-based, tabular and systematic management is adopted, all difficulties can be overcome and regularity can be achieved, thereby avoiding feed waste, saving farming costs, ensuring normal growth, easy sales, and excellent quality of commercial crabs, and maintaining market stability.

2-4 Crab seedling purchase and selection

The crab seedlings are purchased from professional nurseries in Jiangsu and Zhejiang. After a year of practical breeding experience, we concluded that if you want to raise large-sized commercial crabs, purchasing high-quality crab seedlings is the first step in breeding. Hairy crab seedlings can be completely artificially bred, so there are hairy crab seedlings available from November every year to March of the following year!

In addition to the normal appearance (phototropism, strong ability to trace water, ferocious feeding, rapid crawling after leaving the water, prickly feeling when held, and falling apart immediately after release), the main aspects of observing the appearance of high-quality crab seedlings are: (1) body color is yellow with green, light yellow or ginger yellow, shell is transparent, stomach and intestine are full, and appendages are complete. (2) The body surface is smooth and free of foreign matter such as condensed worms or filamentous bacteria. (3) The megalopa larvae are no less than 7 days old and can already cling to the wall and grasp the rope. The cover degree out of the pond is generally not more than 7. (4) The proportion of "white-headed seedlings" with white stomachs does not exceed 10%.

The above points are the conditions that all high-quality crab seedlings should have, and none of them can be missing.

Poor quality crab seedlings can be easily identified from the following points: (1) The proportion of crab seedlings with mixed black and white or white and light yellow color is generally less than 5%, and they are small and have empty stomachs without food. (2) The proportion of "white-headed crab seedlings" with white stomachs is too high, often exceeding 30%. (3) Although the body color of the seedlings is normal, also ginger yellow, there are foreign objects such as filamentous bacteria and polycystic ovary on the body surface. (4) There are still a large number of dead seedlings in the pond. (5) The age of the megalopa larvae is less than 6 days, and the desalination time is less than 4 days and the desalination salinity exceeds 10. Crab seedlings that meet one or more of the above conditions can be determined to be poor quality crab seedlings.