Freshwater lobsters raised in rice fields can generally reach 400-500 kg per mu, and can reach 600 kg when the yield is high. Shrimp farming in rice fields can eat aquatic organisms that consume fertilizers, such as weeds in the fields, which not only saves labor for weeding, but also eliminates mosquitoes and flies that harm people and animals. In addition, shrimp keep moving and foraging in the rice field, which can not only help the rice field loosen soil, live water and ventilate, but also increase dissolved oxygen in the field, and at the same time excrete a lot of feces through metabolism, thus achieving the effect of maintaining and increasing fertilizer. ?

1, the choice of rice fields?

To raise freshwater lobsters in rice fields, we should choose rice fields with abundant water sources, no drought or flood, fresh water quality, no pollution, fertile soil, good water retention and sufficient sunshine. Although the water quality of some mountain streams or springs is relatively poor and the water temperature is relatively low, if we can have a long process, or cross the rice fields where shrimps are not raised and then flow into the rice fields where shrimps are raised, the water temperature will rise, which is also suitable for raising shrimps. ?

2. rice field transformation?

In order to facilitate production management and daily feeding, the area between drainage ditches is generally regarded as feeding area. Dig a circulating buffer ditch with a depth of 0.5~0.6 m and a width of 1.0~ 1.2 m from the inside of the embankment, and turn up all the soil on the embankment, so that the height of the embankment can reach 0.8~ 1.0 m and the top width can reach 0.6. Ridge should be compacted and the inner slope should be smooth. At the same time, the inner side of the ridge top should be surrounded by a closed protective wall with plastic film. The height of the fence is 0.4 ~ 0.5m on the ground and 0. 1 ~ 0.2m underground ... The upper and lower entrances and exits shall be provided with escape prevention nets. ?

In order to facilitate shallow irrigation, drying, application of chemical fertilizers and pesticides or fishing in rice fields, shrimp ditches and ponds must be excavated in shrimp paddy fields. Shrimp ditch can be excavated after transplanting, and its opening mode should depend on the shape, area and direction of field drainage outlet. If the paddy field is small, it can be made into the shape of a "field"; If it is a long and big field, it can be opened into an inner "well" shape or an inner "field" shape, and the width and depth of the ditch are 0.3~0.4 meters respectively. Shrimp ponds can be opened at the intersection of shrimp ditches or at the four corners of fields, which are connected with the shrimp ditches. Shrimp ponds are generally 1.0m square and 0.8 ~ 1.0m deep. ?

The inlet and outlet of shrimp culture in rice field should be well opened and located on the diagonal ridge of rice field, so that the water in the whole rice field can be smooth during the cultivation process. Barriers should be set at the entrance and exit to prevent shrimps from escaping. ?

3. Shrimp stockings?

Stocking time: whether it is the shrimp species of the year or the parent shrimp holding eggs, we must strive for an "early" word. Early release can not only prolong the growth period of shrimp in rice field, but also make full use of a large number of natural bait resources cultivated after fertilization in rice field. The regular stocking time is usually in June 165438+ 10 or the end of March of the following year. ?

Stocking density: 30~40 kg brooding parent shrimp per mu of paddy field. Young shrimps can also be released in April-May of the following year, with 1.2 ~ 1.5 million per mu of paddy field. Pay attention to the fact that the parent shrimp should be fed directly to the peripheral ditch for wintering, and then lured to the rice field for growth when the seedlings turn green. ?

Generally, there are two feeding and releasing modes:?

(1) Summer stocking: young shrimps bred artificially in that year were mainly stocked. The stocking time is from July to September. Young shrimps1.5 ~ 20,000 per mu of shrimp ditch. ?

(2) Stocking in winter: generally, it is carried out in June 5438+February, and about1~1.5000 shrimps are stocked in each acre of shrimp ditch. Where conditions permit, shrimp culture can be conducted in two seasons, namely, green shrimp in July-June and freshwater lobster in June-February. ?

4. Feeding management?

(1) Feeding: Feeding shrimp in rice fields should be timed, fixed-point, quantitative and quality-guaranteed. Feeding once every morning and evening in the early days; Feeding at 6 o'clock in the evening. Feed varieties are mostly small miscellaneous fish, snail meat, mussel meat, earthworm, animal viscera, silkworm chrysalis, corn, wheat and barley powder. You can also feed an appropriate amount of plant feed, such as water hyacinth, water hyacinth and duckweed. The daily feeding amount is 3~5% of the shrimp weight. Check the eating situation of shrimp regularly. The bait fed on the same day is eaten within 2~3 hours, indicating that the amount of bait is insufficient, and the amount of bait should be increased appropriately. If there is any surplus the next day, the amount of bait should be reduced appropriately. ?

(2) Eliminate the enemy's harm: There are many enemies in shrimp farming in rice fields, such as centipedes, snakes, waterfowl, eels, rats and so on. In the early stage of shrimp release, the stems and leaves of rice plants were not flourishing, and there was a big gap in the water surface of the field. At this time, the shrimp is also small, with weak mobility, poor ability to avoid enemy harm and easy to be attacked by enemy harm. At the same time, freshwater lobsters need to molt and grow every once in a while, and when molting or just molting, they are most likely to become palatable bait for the enemy. At the time of harvest, shrimp may crawl around because of shallow water discharge, and the target will be bigger, and it will be easily preyed by birds and animals. In this regard, it is necessary to strengthen field management and catch the enemy in time. In addition, when shrimps are stocked, domestic ducks are also prohibited from entering the ditch to avoid losses.

Lobster (scientific name: Palinuridae) is the general name of species under the family Lepidoptera Lobster. Also known as prawns, leading shrimps, shrimps, sea shrimps, etc. Its head and chest are thick, its shell is hard and colorful, its abdomen is short, its body length is generally between 20-40 cm and its weight is about 0.5 kg. Some of them have no claws, and the next day their abdomen and limbs can be transformed into claws. The heaviest can reach more than 5 kilograms, and it is called lobster tiger. The body is thick and cylindrical, the back and abdomen are slightly flat, the head and breastplate are developed, thick and prickly, there are a pair of powerful supraocular spines in the center of the front edge, and there is a closed gill chamber. Mainly distributed in tropical waters, it is a precious seafood. Gaoyou lake lobster, Shao Bolong shrimp and Xuyi lobster are also famous.

Shrimp has strong adaptability. According to the investigation, it can survive in lakes, rivers, ponds, canals and paddy fields, and even in some water bodies where it is difficult for fish to survive. Lobster has a strong adaptability to dissolved oxygen in water. It can not only climb ashore in an anoxic environment, but also lie on its side on the water with the help of floating plants or aquatic plants in the water and breathe through its gills to survive.

Lobsters have a strong tolerance to hypoxia, and can climb ashore for gill breathing and survive in an anoxic environment. The pH value of water is in the range of 5.8 ~ 9, and it can still survive normally when the dissolved oxygen is lower than1.5 mg/L/L. The normal growth requires that the dissolved oxygen be above 3 ml/L.

Lobsters have a strong tendency to flow, like fresh water and flowing water, go upstream and live in groups. In aquaculture ponds, groups often gather around the water inlet. In rainy days, shrimp can stay or escape on the shore for a short time against the current, and climb ashore to live when the water environment is not suitable, so the breeding ground should be fenced to prevent escape.