Method and device for large-scale breeding of crayfish in net cage of greenhouse

Abstract

The invention belongs to the technical field of crayfish breeding, and discloses a method and a device for large-scale breeding of crayfish in a net cage of a greenhouse. The method comprises the steps of building the greenhouse on a cement pool; building the net cage in the cement pool, and planting water hyacinth around the net cage; selecting parent crayfish in August and September, wherein theweighs of the parent crayfish are 40-50g, feeding mainly with animal feed, supplementing with pellet feed, and controlling the feeding amount to be 3-6% of the total weight of the bred crayfish; after the incubation of the parent crayfish is completed, removing the net cage and the parent crayfish in the net cage; continuing to breed the floating plants and animals through the fertilizer water inthe pool so as to provide astaxanthin for ingestion of the crayfish; after crayfish larvae are incubated in the cement pool for two weeks, collecting by using a small-mesh ground cage and then transferring into a big pond for further breeding. The method increases the water temperature during breeding, thus promoting the gonad development of the parent crayfish, shortens the embryo hatching time,and enabling the emergence of the seedlings to be synchronous as much as possible; furthermore, the net cage is used for isolating the parent crayfish and the crayfish larvae after incubation, so that the cruel killing of the crayfish larvae by the parent crayfish is reduced, the survival rate of the crayfish larvae is 90% or above, and the large-scale breeding is realized.

Description

Technical field [0001] The invention belongs to the technical field of lobster breeding, and particularly relates to a method and device for large-scale breeding of crayfish in a greenhouse net cage. Background technique [0002] At present, the existing technology commonly used in the industry is as follows: the asynchrony of the growth and reproduction of crustaceans has always been a problem that plagues the world's breeding industry. Freshwater crayfish is particularly difficult to compare with marine prawns (such as Chinese prawn and vannamei) and freshwater prawns (such as green prawns, macrobrachium rosenbergii, etc.). This is because: (1) marine prawns and freshwater prawns The level of gonadal development can be observed from the outside of the head breastplate, and the problem of simultaneous spawning can be initially solved by manual selection. However, the head breastplate of freshwater crayfish is thick and opaque, and it is more difficult to distinguish the degree o...

AI Technical Summary

Problems solved by technology

The phenomenon of crayfish broodstock eating larvae is very serious. If the hatched larvae cannot be isolated from the broodstock, the survival rate of the larvae will be very low because the broodstock cannibalism will lead to a very low survival rate of the larvae, and the asynchronous breeding of crayfish makes this One problem is more prominent, which is a key constraint factor for large-scale breeding of crayfish

If artificial isolation is used, each female shrimp needs to be placed separately when hatching, and the female shrimp will be taken away after hatching to collect juvenile shrimp, which cannot meet the needs of large-scale breeding at all.

[0004] In summary, the problems in the prior art are: crayfish fecundity is low, and large-scale breeding requires a large number of parents

The existing artificial breeding methods generally have problems such as low survival rate of broodstock, poor synchronization of batch spawning and hatching, low survival rate of seedlings, low seedling production and high cost, which are far from meeting the needs of aquaculture production

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