CN1114132A - Feminizing induction technique for Chinese prawn - Google Patents

Abstract

The induction method for controlling the feminization of prawn features that the young prawns are treated in warm water for 45-110 seconds within 12-25 hours after they have been incubated out and then cultured as usually. The rate of female can reach 70-75% and the average length and weight of prawn are obviously increased. The prawn has improved activity, high growing speed and strong disease resistance.

Description

The Chinese prawn inductive technology of feminizing

The present invention relates to the cultural technique of a kind of animal, specifically the sex controlling technology of a kind of prawn.

Chinese prawn is commonly called as prawn, prawn, prawn, is oriental prawn again, is one of important fish product of China's Marine Fishing Industry.Chinese prawn is individual big, has abundant nutritive value, is the marine product that people like food.Along with improving constantly that growing needs in shrimps market, the world and Chinese people daily necessities are asked, the quantity of natural marine products shrimp can not reach the level that it is needed already.Therefore propagating prawn artificially has obtained large development.According to the state of development of present Chinese prawn aquaculture, it is limited only from continuous expansion cultured area output being improved year by year, so the scientific research personnel just setting about from the required best ecotope of shrimp culture starting with, to seek the optimum growh ecological factor.Though these researchs have obtained certain achievement, practice shows that the per unit area yield quantity that improves culture shrimp by this approach also is limited.So someone think Chinese prawn propagate artificially industry at present institute reach level near limit, be difficult for having broken through! How to improve prawn output in the case significantly, then become the difficult problem that relevant scientific and technical personnel earnestly seek.

Find that under study for action the female shrimp of Chinese prawn is individual bigger than male shrimp, growth is fast, the coefficient of condition height, and ovum female shrimp in bosom is especially true.And at natural marine products and propagating artificially in the colony, the ratio of female shrimp and male shrimp is all in 1: 1 approximate range.If the female shrimp ratio in the shoal of shrimps improves, be about to male shrimp and be converted into female shrimp, then under the situation of identical shrimp amount, the overall weight of shoal of shrimps and volume can be significantly increased, and can improve significantly thus and support shrimp output.

But male shrimp is converted into this sex controlling technology of female shrimp beyond example still both at home and abroad at present, and also different with common shrimps of the reproductive habit of Chinese prawn.Female shrimp, the male shrimp of Chinese prawn carry out post-coitum, and the spermatophore that male shrimp will keep sperm is inserted in the receptaculum seminis of female shrimp and stored.Lay eggs after the bosom maturation of ovum of female shrimp, the spermatophore that is hidden in simultaneously in the receptaculum seminis discharges sperm, and the shrimp ovum is fertilized in seawater, is grown, and hatches the prawn young at last, through four juvenile stage with repeatedly cast off a skin and grow up to juvenile prawn.To carry out the female conversion of Chinese prawn so, will solve when the prawn sex breaks up, what the sex controlling factor is, manually could control and how to make male shrimp be converted into a series of problems such as female shrimp.

The biotechnology such as the steroid hormone inductive technology that have according to phenomenon are handled Chinese prawn fertilized egg with 17 α-Methyltestosterone and 17 β-estradiol, and the result shows that the two has no effect to the sex ratio of Chinese prawn.Inducing processing if carry out sex with chemicals, then can cause drug accumulation, and then can have influence on the quality of shrimp, also is unfavorable therefore.

Purpose of the present invention just provides a kind of sex controlling technology of Chinese prawn, with the sex ratio of manual intervention shoal of shrimps, improves the ratio of female in the shoal of shrimps, makes shoal of shrimps under the constant situation of individual amount, and volume and weight obviously improves.

The female shrimp that the present invention is achieved in that at Chinese prawn laid eggs back 12-24 hours in, with 30-38 ℃ of warm water bathing shrimp ovum, put into the hatchery after 45-110 seconds time of bathing again and grow seedlings with conventional method, can realize thus Chinese prawn by male to female conversion, the shrimp seedling obtains to feminize.

Key point of the present invention has been that clearly the time of Chinese prawn Sex Differentiation is to hatch period at the shrimp ovum, and the sex controlling factor is the hatching environment chemical factors such as water temperature in period.Determined Chinese prawn sex artificial induction's possibility thus, and made the transform into possibility of male shrimp to female shrimp.The key of the inductive technology of feminizing then is to determine optimization process period, optimum treatmenting temperature and optimization process time span.The present invention is through prolonged and repeated test, explored optimum processing parameter, and find to have handled beginning period too early or late excessively, inducing all of the shrimp that feminizes gets nowhere, if and the shrimp ovum carries out in after its output 16-20 hours the period of handling, then feminisation shrimp rate can reach the highest.In addition, the prawn feminisation induces the temperature of processing then to induce the basic no change of result as low excessively (＜30 ℃); Then occur the extreme of fertilized egg is destroyed as temperature too high (＞38 ℃), make it dead.Induce time of processing too shortly also not have a marked change, then make fertilized egg being hurt as long.

Shrimp seedling after abductive approach of the present invention is handled is after forming colony, and through actual measurement and inspection, female shrimp accounts for 70-75% of sum, promptly has 20-25% male shrimp to change into female shrimp.Verification method is to take shrimp soma sections observation, and the result shows that profile is female person in the prawn colony, and the sexual gland structure of a part and the common female shrimp of control group are identical, can regard the female shrimp of primary as; The sexual gland structure of another part is between female and the intermediate form male gonad structure, can confirm as to induce success and property conversion person is the shrimp that feminizes.Show that with the isozymogram analysis result bands of a spectrum of this shrimp that feminizes increase, increased activity, thereby the shrimp seedling shows obvious growth advantage and resistance against diseases, and individual two to three times of can reach common prawn.Through actual measurement, the shrimp body average body length of experimental group is than the increase by 23% of control group, and average weight increases more than 55%.Thereby utilize the technology of the present invention, and not only can shorten the breed phase of prawn, and the female individuals in the cultured population is increased, output obviously improves, and economic benefit is very remarkable.

Embodiment: in Bohai Sea Gulf, the Chinese prawn sex of feminizing is induced, promptly after shrimp ovum output, put into the hatchery with 32 ℃ of warm water bathing shrimp ovum after 60 seconds in 20 hours, do not need any giving someone extra help, conventional method by the hatching of shrimp seedling is grown seedlings, and raises to becoming shrimp through conventional method again.The female sex rate of actual test shoal of shrimps is 72%, and be 72 days the vegetative period of the shrimp that feminizes, long 12.71 centimetres of the shrimp body average body of shoal of shrimps, average weight 23.5 grams.

Claims (2)

1, a kind of Chinese prawn inductive technology of feminizing is characterized in that the shrimp ovum after output in 12-14 hours, grow seedlings with conventional method again after 45-110 seconds with 30-18 ℃ of warm water bathings.

2, inductive technology according to claim 1 is characterized in that carrying out in shrimp ovum processing 16-20 hours after being preferably in its output period.