CATDOLL : CATDOLL: Is it okay to raise grass carp and shrimp together? Does grass carp eat shrimp?

Is it okay to raise grass carp and shrimp together? Does grass carp eat shrimp?

Grass carp and shrimp can be mixed in the same pond. Because grass carp does not feed on shrimp, and the presence of shrimp can increase the species richness in the pond, making the entire pond ecosystem more stable. In this way, not only can fish and shrimp grow better, but the incidence of grass carp and shrimp can also be reduced, thereby reducing the risk of breeding.

Grass carp and green shrimp can be mixed in the same pond. Because grass carp mainly feed on floating algae, duckweed, earthworms, etc., and do not eat shrimp. Moreover, mixing shrimp and grass carp in the same pond can effectively increase the stability of the pond ecosystem and keep the water quality stable. In this way, the chance of fish and shrimp getting sick can also be reduced.

Grass carp and shrimp can be raised together in the same pond. Because grass carp does not feed on shrimp, and the presence of shrimp can increase the species richness in the pond and make the entire pond ecosystem more stable. In this way, not only can fish and shrimp grow better, but also the incidence of grass carp and shrimp can be reduced.

It is certainly possible to raise the grass carp and shrimp together as you mentioned. The grass carp only eats some plankton or plants, and does not eat shrimp.

Do you know the tilapia farming technology? Can you share it?

1. Breeding Model

Every change or progress in the aquaculture industry begins with a change in the aquaculture model, and tilapia aquaculture is no exception, because the aquaculture model is the easiest to change. From the development of tilapia aquaculture in China, the aquaculture model of tilapia has gone through the traditional fish-pig mixed aquaculture, fish-duck mixed aquaculture, intensive aquaculture in recent years, and now large-scale mixed aquaculture. No matter which aquaculture model is, farmers have made flexible changes according to market changes, which is a wise choice for farmers.

1. Intensive breeding model

The intensive farming model of tilapia developed rapidly in the years when the market was good. Intensive farming, that is, pure tilapia farming, can produce more than 5,000 per mu, creating many tilapia myths. The representative areas of the intensive farming model are tropical and subtropical farming areas such as Wenchang, Hainan and Nanning, Guangxi. The seedling density is 2,500-4,000 per mu, and the feed coefficient is 1.3-1.5 throughout the process. The farming cost is 3.5-4 yuan per catty. The pond needs to be equipped with a strong oxygenation capacity, and the pond with good conditions even has a sewage system.

Hainan takes advantage of its unique climate and can raise fish three times a year; while Nanning relies on its domestic market advantage, and fish prices have been relatively strong. Tilapia raised in the intensive mode grows fast and has a high yield, so it is highly praised by farmers in both places. In addition, the peak period for tilapia to be put on the market is from October to December, which is also the time when the price is the lowest. Tilapia raised in the intensive mode can be put on the market one month earlier, so farmers can take advantage of the time difference and avoid the impact of peak fish production on fish prices.

However, in the past two years, intensively farmed tilapia has faced the dual challenges of streptococcal disease and weak exports. With the market still uncertain in 2016, many large tilapia farmers are still in a wait-and-see mood.

2. Tilapia-shrimp polyculture model

Tilapia-shrimp polyculture is a classic aquaculture model, which is also due to the frequent occurrence of shrimp diseases and the sluggish tilapia market in recent years. This model is distributed in Taishan, Zhuhai, Zhanjiang and Maoming, Guangdong.

The tilapia-shrimp mixed culture model is mainly based on tilapia, supplemented by shrimp. The two complement each other and improve the ability to resist risks. Farmers generally start to coarse tilapia fry and shrimp fry in mid-to-late March. The density of tilapia fry is 2500-3000 per mu, and the density of shrimp fry is 20,000-30,000 per mu, with the second generation fry as the main. After coarse, when the size of tilapia fry reaches 50 per catty and the size of shrimp fry reaches 800 per catty, tilapia and shrimp can be mixed in the pond. Some farmers also directly put shrimp fry in the tilapia fry pond, and then replenish the fry in time during the breeding process. Farmers with sufficient ponds can prepare for the second batch of coarse in the middle of the first batch to achieve the goal of maximizing breeding efficiency. Tilapia is fed throughout the process, while white shrimp is not fed or fed less. The omnivorous characteristics of shrimp are used to improve the utilization rate of feed and the purification capacity of the pond, and reduce breeding risks and costs.

Prawns can be harvested in early June and caught in ground traps. The annual yield per mu is about 200 catties. Calculated at an average price of 15-20 yuan per catty, the per mu output value of prawns is 3,000-4,000 yuan, which can offset most of the tilapia feed expenses. Tilapia can be put on the market in batches in mid-September, with a feed coefficient of about 1.3 and a per mu yield of 2,500-3,000 catties. Taking advantage of the high added value of prawns, this model can greatly increase the farming income of tilapia.

3. Intensive breeding of large-sized tilapia

In recent years, the market of large-sized tilapia weighing 3-4 jin has been very stable, with an average price of about 10 yuan per jin, and a considerable profit margin. It has been sought after by some farmers, and the breeding areas are mainly concentrated near high-consumption cities such as Zhuhai and Foshan. This model generally releases seedlings in March, with 3,000-4,000 seedlings per mu (size 7-8 days). After 3 months of breeding, farmers can choose to sell some commercial fish or divide the ponds for further breeding to speed up capital turnover and reduce breeding risks in high temperature seasons. After breeding until the end of the year, the size of tilapia reaches 3-4 jin, and farmers can sell fish in batches according to market conditions. Taking farmers in Pingsha, Zhuhai as an example, the annual per mu yield of tilapia under this model can reach 6,000 jin, and the per mu profit is as high as 12,000-15,000 yuan.

Despite its lucrative profits, this farming model is only suitable for farming areas close to wholesale markets or urban consumer groups. These areas not only have strong consumption capacity for large-sized tilapia, but farmers can also directly connect with the market to obtain greater profit margins.

In addition, large-sized tilapia must survive the winter, because the price of tilapia is the highest during the lean period after the New Year, and whether it can survive the winter has become the most concerned issue for tilapia farmers. Therefore, this model is only suitable for ponds with winter sheds and sufficient groundwater or geothermal heat. This model has a long breeding cycle and high costs. Farmers should choose according to their own pond environment and market environment, and should not blindly follow the trend.

4. Three-dimensional breeding mode

Three-dimensional farming includes traditional fish-duck mixed farming and fish-pig mixed farming, which are mainly concentrated in eastern Guangdong and inland large water surface farming areas. Taking fish-duck mixed farming in eastern Guangdong as an example, the stocking density of tilapia is 800-1000 per mu (size 8-9 days), and it is also matched with filter-feeding and omnivorous fish such as bighead carp, silver carp and dace. Feed the fry with starter feed to improve the survival rate. No feed or less feed is added in the middle of the breeding period. When the fish reaches a size of more than half a catty, tilapia feed is started to fatten them. Some farmers will feed duck feed when waiting for the price to be sold. The feed coefficient throughout the process is about 0.6-0.8, and the breeding cost is 2-3 yuan per catty.

According to industry insiders, the current cost of intensive farming of tilapia is generally 3.5 to 4 yuan per catty, mixed farming is 3 to 3.5 yuan per catty, and vertical farming is 2 to 3 yuan per catty. Under the current low price situation, the first two farming models are loss-making businesses. Therefore, for now, vertical farming is still the best farming model for tilapia farmers to avoid market risks.

In the short term, the three-dimensional farming model will not disappear, but with the shift in policy, the farming industry and environmental protection will be linked, and the government will strengthen the control of the pond farming environment. Some areas have banned the construction of pig houses and duck sheds in ponds. In the long run, farmers still need to make timely changes to cope with changes in the overall environment.

5. Large-scale polyculture model

Large-scale polyculture is to mix tilapia with carp, dace, grass carp, bighead carp, silver carp, etc., making full use of the water space and the feeding habits of fish, thereby improving the efficiency of the entire breeding process. The following table shows the stocking and income of tilapia farmers in Enping City, Guangdong Province, for your reference.

Compared with three-dimensional farming, the large-scale polyculture model of tilapia avoids drug residues and bottom pollution in livestock and poultry manure, has higher operability, and there is still a lot of room for exploration.

6. There are some other breeding modes

Such as marine tilapia farming in coastal areas, intensive farming in high-level ponds, and switching to marine farming after freshwater farming to improve the flavor and taste of tilapia.

2. Seedlings

"To get rich through breeding, seedlings must come first." Seedlings are the foundation of breeding. Once selected, their innate characteristics cannot be changed. Especially for tilapia, which is a low-profit variety, the quality of seedlings often determines the success or failure of breeding.

1. Seedling selection

Try to choose company-owned and branded seedlings. Although the impact of this year's cold wave on the tilapia seedling industry is not as great as in 2008, small seedling farms will still seize the opportunity to seize the market. Farmers must not be too eager to invest in seedlings and mistakenly choose inferior seedlings, which will delay production.

In terms of variety selection, GIFT tilapia dominates the market with its fast growth rate. Oni tilapia grows slowly but has higher cold and disease resistance than GIFT. After the industry has experienced various baptisms, farmers should rationally choose fish fry varieties according to their own breeding habits and plans, and avoid ignoring the quality of fish fry in pursuit of speed.

2. Planting seedlings

Regarding stocking, there are no more conventional precautions such as pond cleaning and water transfer. We will just remind farmers of some key points. The water body for stocking should not only be concerned about its safety, but also its stability. Stable water bodies have richer plankton and fry are less likely to be stressed. It is recommended to use avermectin or ivermectin to kill insects in the pond 2 days before stocking, and stock the fry when the water temperature is stable above 20℃. High-protein eel powder and turtle powder can be used to feed the fry to improve the survival rate and immunity of the fry. After stocking, it is recommended to kill insects once a week, and regular disinfection is required in low temperature weather to prevent saprolegniasis. Finally, do a good job of preventing natural enemies (water snakes, birds, tadpoles, etc.).

1. Farming conditions Before stocking seedlings, the pond must be cleaned thoroughly and other fish, especially tilapia, removed. Otherwise, four generations will live together and compete for food and space.

Usually quicklime or tea bran powder is used to clean the pond. If quicklime is used, dry the pond first, drain the pond water thoroughly, and then apply quicklime at 100kg/mu. When filling and draining water, use a 30-mesh mesh to filter to prevent other tilapia from mixing into the pond.

2. Stocking density If you cultivate seedlings, the stocking density of the fish seedlings is 30,000-100,000 per mu. If you raise adult fish, there are two major models. One is pure breeding of a single species. The stocking density should be adjusted according to the size of the breeding water body. It should be ventilated and transparent, and the feed should be sufficient. For example, a fish pond with a water depth of 3m and an area of ​​10-20 mu, the stocking density is 2000-3000 per mu, and 1.25kg per fish can be raised in one year. At the same time, 20-30 bighead carp and bream should be stocked per mu to regulate the water quality, and some black snakehead or catfish should be stocked to prevent incomplete pond cleaning, or other species of tilapia and wild fish from growing and breeding in the pond during drainage and irrigation. The second is three-dimensional multi-species mixed breeding, which mainly involves the fish as an omnivorous fish in the traditional four major carps and famous and special ponds to remove residual feed and feces. The stocking density of this model is 500-1000 per mu.

3. The key to feeding intensity is to feed enough feed. First of all, it is necessary to select the feed. Instead of choosing the feed, it is better to choose the feed manufacturer. It is necessary to choose the brand feed produced by large and old factories, which has a high safety factor. Secondly, among sinking feed, semi-sinking feed and floating feed, floating feed is preferred. Feed should be fed at regular times, fixed points and quantitatively. Feed twice a day, at 10 am and 3 pm. Do not feed in the hot summer, especially when the weather is hot and humid, to prevent the fish from overeating. Insufficient dissolved oxygen at night will damage the digestion and absorption function of the fish's stomach and intestines.

4. Daily management focuses on regulating water quality and improving the bottom environment. Inspect the fish pond in the morning and evening, observe the water color, smell the water vapor, and observe the activities of the fish to prevent the fish from lacking oxygen, especially when the weather is hot and humid. Once the fish are found floating, the aerator should be turned on in time. If the water quality is found to be too rich, reduce the feed, inject new water to reduce the water concentration or change the water, especially in summer, deepen the breeding water level. Pay attention to the observation of the pond base and drainage and irrigation outlets, and prohibit other tilapia from mixing into the fish pond. At the same time, pay attention to improving the bottom environment to create a good ecological environment for the healthy growth of fish.

5. Disease prevention and control: This fish not only grows fast and has a large body, but also has strong disease resistance. It usually rarely gets sick or even never gets sick. It is usually easily infected by bacteria and dies due to abrasions or injuries caused by fishing or transportation. It is especially prone to Saprolegniasis after fishing or long-distance transportation when the weather is cold. On the day the fry are put into the pond, iodine or chlorine preparations should be used to dissolve water and spray the entire pond.

When raising tilapia in the breeding room, you must pay attention to the temperature and sunshine time, and pay attention to the nutritional method of the feed. You must choose nutritious feed of the same brand.

The pond should be surrounded by convenient drainage, no pollution sources, sufficient sunlight and good water quality. The pond should preferably have a sandy mud bottom, the bottom of the pond should be flat and free of impurities, the water depth should be generally 1.8-2.5m, and it should be equipped with an aerator. 7-10 days before stocking the fish, the fish pond water should be cleared and disinfected with quicklime. The amount of quicklime used per mu is 150 catties, and a certain amount of fermented fertilizer is added to cultivate plankton. The inlet and outlet should be blocked with mesh or iron gauze. The water temperature should not be lower than 18℃ during the breeding process. When the water temperature rises above 18℃ in March and April, stocking begins. For ponds mainly stocking tilapia, 2000-3000 2-3 inch fish are placed per mu. In ponds mixed with silver carp, bighead carp and grass carp, 1000-1500 orni fish of the same specifications are stocked per mu. The feed is mainly protein feed, and green feed is supplementary feed. The crude protein content in the feed should exceed 25%. Tilapia feed, wheat bran or oil cake can be fed once in the morning and afternoon every day. The daily feed amount for fish before they grow to half a catty is 7% of their body weight, and it is changed to 5% after half a catty.

To farm tilapia, a pond with an area of ​​5 mu and a depth of 2 meters should be built in a place far away from pollution sources and with convenient drainage and irrigation. The bottom and walls of the pond should be covered with mulch to prevent water seepage. Before using the pond, it should be disinfected with quicklime to avoid the presence of infectious bacteria.