Reasonable polyculture: In order to save the cost, white shrimps can be put into the fish pond for autotrophic breeding or mixed culture of tilapia summer flowers. The residual bait and feces of the fish are used as bait for white shrimps and tilapia, while white shrimps and tilapia are high-quality bait for the fish pond, so as to balance the ecology of the fish pond.
Daily management: The water temperature is required to be14 ~ 30℃, the salinity is12 ~ 35%, the PH value is 7.8 ~ 8.4, and the dissolved oxygen is more than 4 mg/L, and the daily variation range should not be too large. The daily water exchange rate is generally required to be1/3 ~/kloc-0.
If the exchange condition of water is poor and the stocking density is too high in the process of culture, it is easy to have anoxic floating head, so mechanical pumping or aerator should be adopted in time to increase oxygen. In addition, we should often patrol the pond and pay attention to safety in production.
Leptospira likes to live in rivers and streams with gravel bottom and fast flowing water, and often shovels moss and algae on stones with the developed cuticle of mandible. Laying eggs in shallow rapids from June to August every year. Mainly distributed in streams in Shanghai, Jiangsu, Anhui, Zhejiang, Fujian, Taiwan Province and other places.
Acrossocheilus fasciatus belongs to CYPRINIDAE, CYPRINIDAE, CYPRINIDAE, and the genus Acrossochelus. Commonly known as: grouper, rose fish. The body is slender, flat on the side, slightly raised on the back of the head, and the abdomen is round and shallow arc. The head is medium-sized, with a flat side and a slightly pointed front end.
Widely distributed, it is a small economic fish in the producing area with delicious meat. Eggs are poisonous, and eating them by mistake can cause diarrhea, abdominal pain, dizziness, vomiting and other poisoning symptoms; Cats, chickens and other animals eating fish eggs will cause death. Long-term heating can destroy toxins. Because of its bright body color, Zhejiang selected 3.5 cm juvenile fish of the same kind for export as ornamental fish, which created considerable value.
Extended data
pond culture
1, culture pond conditions: the pond can be built in the low and middle tidal areas in the reclamation area or by using the original shrimp culture pond. The requirements are as follows: the bottom material is sandy and semi-sandy, and the hard mud bottom is also acceptable; The water quality in the surrounding sea area is pollution-free and transparent; The fish pond area is 5- 10 mu, and the water depth of the pond is more than 1 m.
2. Clear ponds and artificial reefs are put into use. After exposure and dredging, some rocks are laid at the bottom of the pond or some worn-out tires and tile water tubes are put into use to adapt to the habit of groupers who like to drill holes.
3. Fish stocking. The cultured fish species are required to be vigorous, disease-free, black in color, and to be cultured separately. The stocking density must be adapted to local conditions, and the general fish species specification is about100g/tail, and about 0.5 tail can be stocked per square meter.
4. Feeding management
Bait feeding. The bait is mainly fresh small miscellaneous fish, preferably live bait, and cut into blocks of appropriate size according to the specifications of the fish species for feeding. When feeding, quantitative feeding is adopted, which generally accounts for 10- 15% of the fish weight in the early stage and 5- 10% in the later stage.
The best feeding time is 5-6 am and 7-8 pm.
In order to save the cost, white shrimp can be put into the fish pond for breeding grouper, or tilapia can be mixed with summer flowers. The residual bait and feces of grouper are used as bait for white shrimp and tilapia, while white shrimp and tilapia are high-quality bait for grouper, so as to balance the ecology of the fish pond.
Daily management. Grouper is very sensitive to the change of water environment, so it should be paid attention to in daily management. When cultivating, the water temperature should be 14-30℃, the salinity 12-35%, the PH value should be 7.8-8.4, the dissolved oxygen should be above 4 mg/L, and the daily change range should not be too large. The daily water exchange rate is generally1/3-1/4.
In the process of breeding, if the exchange condition of water is poor and the stocking density is too high, it is easy to have anoxic floating head, so mechanical pumping or aerator should be adopted in time to increase oxygen. In addition, we should often patrol the pond and pay attention to safety in production.
Harvest. Grouper has poor tolerance to low temperature, so it is generally appropriate to finish harvesting before the cold current comes. A few groupers that do not meet the commercial specifications should be wintered.
net-cage culture
1, selection of breeding grounds and cage making are similar to cage culture of bass.
2. Breeding season. The growth period of grouper is generally 5- 1 1 month in Zhejiang sea area, and it takes 14- 16 months for grouper to grow from 50-100g fish to 400-600g commercial fish. Generally, two breeding cycles are adopted to arrange production.
One is to breed fish from about100g purchased in May-July of the first year until the weight reaches150-200g before winter, and then overwinter them until they are put on the market before winter of the next year; The other is to put large-scale fish species weighing 200 grams in April-May, and 400-600 grams of commercial fish can be raised for sale before winter in that year.
3. Breeding density. According to the production practice and test results for many years, the stocking density of cage-cultured grouper is considered to be10kg/m2, which is 3× 3× 3m. This stocking density can achieve high survival rate, high total weight gain rate and net yield, and low feed coefficient.
4. Bait and feeding technology. It takes 7- 10 days for the fingerlings to adapt to the environmental conditions before they can start feeding. Before feeding formally, it should be tamed, and its bait is mainly offal fish, and the bait coefficient is generally 7-8:1. Several problems should be paid attention to when using compound bait: First, grouper has a strong habit of feeding bait.
There is a great adaptation and transition process from feeding miscellaneous fish to feeding artificial compound bait. Secondly, the formula of compound bait should be reasonable, and its protein content should not be lower than 40%. Thirdly, grouper will vomit if the bait is not palatable or fresh enough, so palatability should be considered.
Fourth, it needs to be made into soft particles, the size of which should be consistent with the diameter of grouper. Grouper is suspicious, and it is highly selective to feed. Therefore, the feeding technology has a great influence on the feeding of grouper. The feeding time is 8- 1 1 in the morning, and the feeding amount accounts for about 5- 10% of the fish's weight. The feeding method should be slow and wait until the fish is finished. Groupers generally don't eat the bait that sinks to the bottom of the cage.
5. Overwintering management. The water temperature drops below 15℃ from1February to April of the following year, and the grouper basically does not eat or swim, and enters the wintering stage.
Selection of overwintering sea area and cage structure. Choose the sea area with slow flow, small wind and waves and the lowest water temperature above 8℃. In order to reduce the influence of tidal current and wind waves on overwintering fish, some empty cages should be set around the overwintering cages to slow down the impact of tidal current and wind waves on the overwintering cages, and at the same time, a certain number of overwintering equipment should be set in the cages, with sacks upside down or hard plastic cages and pipes attached.
Stocking density of overwintering fish species. Generally, fish species with a size of 200g/fish are stocked, and the density is 350-400 fish/box. Feeding during the wintering period should be in windy and warm weather, with less feeding, but better bait quality, and try to feed live bait.
In addition, where conditions permit, indoor heating or land plastic greenhouse can be used for wintering.
Baidu Encyclopedia-Grouper Culture Technology