CN111109163B - Breeding method of commercial snakehead - Google Patents

Abstract

The invention discloses a method for breeding commercial snakehead, which comprises the following steps: (1) parent selection and cultivation, wherein snakeheads from different geographical populations are used as breeding materials; (2) and (3) parent line and maternal line breeding: selecting the father line, and taking the growth speed and the bait coefficient as selection indexes; through breeding of 3-4 generations, the growth advantage character index is fixed; selecting a mother line, and selecting by taking the number of eggs laid, fertility rate and hatchability reproductive performance as selection indexes and considering growth performance; breeding for 3-4 generations to fix the indexes of the propagation advantage characters; (3) and (3) producing commodity filial generation, namely, breeding the female parent with the female line individual and breeding the male parent with the male line individual as the male parent to produce the commodity filial generation. According to the invention, through mating of different individuals of a parent system, the special variety for commercial snakeheads with large quantity, high growth speed, strong disease resistance and good meat quality is produced, and the problems of unclear blood relationship of the snakeheads cultured in the prior art, easy inbreeding caused by the unclear blood relationship of the snakeheads, degeneration of the variety, small egg laying amount, low fertility rate and hatching rate, low growth speed of fish fries and fish seeds and low commodity rate are solved.

Description

Breeding method of commercial snakehead

Technical Field

The invention relates to snakeheads, in particular to a method for breeding commercial snakeheads.

Background

Snakehead fish is commonly called snakehead fish, is an economic fish popular with the masses, has tender and few thorns, delicious taste, rich nutrition and high protein content, and also contains various nutritional components of fat, calcium, phosphorus, iron and ash. The snakehead carnivorous fish is called fish and tiger because the carnivorous fish feeds from fish fry to adult fish, and the carnivorous fish has strong tophagy from zooplankton such as rotifer, copepods, cladocera and aquatic insects to fish and shrimp and even jumps out of water surface to prey on water surface insects, the adult fish can jump to more than one meter and has very fierce character. In case of insufficient feed, the phenomenon of mutual eating is serious.

The snakehead has a body length of 30 cm, gonads develop, and sexual maturity begins when the snakehead grows to the second winter age. The brood amount of female fish per kilogram is about 1.5 ten thousand grains. Breeding fish seeds of more than 10cm in a stocking way, and culturing for 11-12 months (including the wintering period), wherein the survival rate is 75% -80%, the average weight of the fish seeds is 0.6-0.7 kg, and the yield per mu reaches 4000-; 16-20 cm of fingerlings in the next year of stocking in 3-4 months, after 8 months of cultivation, the average weight of fingerlings reaches 0.7 kg at the end of the year, the survival rate is more than 90%, and the yield per mu reaches 6000 kg of plus 5000 materials.

The conventional snakehead, namely the common snakehead, is the snakehead which is not bred and has unclear relationship with blood and naturally breeds and grows in a wild state. The commodity snakehead is the offspring produced by crossing after breeding of 2-3 mating lines and is only used as the commodity fish for market.

The defects of the conventional snakehead are mainly shown as follows:

(1) unclear blood margins, which may cause inbreeding, leading to breed degeneration.

(2) The egg laying amount is small, and the fertility rate and the hatching rate are low.

(3) The fry and fingerling growth speed is slow, and the commodity rate is low.

Disclosure of Invention

The purpose of the invention is as follows: the invention aims to provide a method for breeding commercial snakehead, which is characterized in that by collecting snakehead populations with different geographical populations with the spacing of more than 200 kilometers, inbreeding is avoided, reproductive performance is selected as a mother system character special for the commercial snakehead, growth performance is selected as a father system character special for the commercial snakehead, and different individuals of the father and mother systems mate to produce a commercial snakehead special variety with large quantity, high growth speed, strong disease resistance and good meat quality.

The technical scheme is as follows: the breeding method of commercial snakeheads comprises the following steps:

(1) parent selection and cultivation, wherein snakeheads from different geographical populations are used as breeding materials;

(2) the parent and maternal line breeding method comprises the following steps:

(2.1) carrying out paternal line breeding, wherein the growth speed and the bait coefficient are used as selection indexes; through breeding of 3-4 generations, the growth advantage character index is fixed; the growth dominance character indexes are growth speed and bait coefficient;

(2.2) breeding the mother line, and selecting by taking the number of eggs laid, the fertility rate and the hatchability reproductive performance as selection indexes and considering the growth performance; breeding for 3-4 generations to fix the indexes of the propagation advantage characters; the breeding dominance character indexes are egg laying number, fertility rate and hatchability breeding performance;

(3) and (3) producing commodity filial generation, namely, breeding the female parent with the female line individual and breeding the male parent with the male line individual as the male parent to produce the commodity filial generation.

Wherein in the step (1), 3-5 geographical snakehead populations with space distance over 200 kilometers and natural growth are selected as parents.

The method selects the snakeheads with the body surface characteristics of the snakeheads and the anatomical structures of other aspects with the conventional snakeheads variety characteristics, and the individuals are all snakeheads with the winter age and the body weight of more than 2 kilograms as parents.

In the step (2.1), the overwintering weight of the snakeheads in the current year is required to reach more than 200 g, the average weight at the end of 10 months in the 2 nd year is required to reach more than 1500 g, and the bait coefficient is required to be within 1.35.

In the step (2.2), when breeding the female line, the amount of eggs per kilogram is required to reach 20000 grains, the fertility rate reaches 85%, the hatchability reaches 90%, the survival rate of the fry reaches more than 80%, the overwintering weight in the current year reaches 150 g, and the average weight at the end of 10 months in the 2 nd year reaches more than 1200 g.

Has the advantages that: according to the invention, through mating of different individuals of a parent system, the special variety for commercial snakeheads with large quantity, high growth speed, strong disease resistance and good meat quality is produced, and the problems of unclear blood relationship of the snakeheads cultured in the prior art, easy inbreeding caused by the unclear blood relationship of the snakeheads, degeneration of the variety, small egg laying amount, low fertility rate and hatching rate, low growth speed of fish fries and fish seeds and low commodity rate are solved.

Drawings

FIG. 1 is a flow chart of the snakehead fish breeding method of the invention.

Detailed Description

In this example, in south China, Jiangsu, China, aquatic product professional cooperative society, different geographical populations of snakeheads are collected from Taihu lake, Hongze lake and Weishan lake basin respectively as materials, reproductive performance is selected as a special maternal trait for commercial snakeheads, growth performance is selected as a special paternal trait for commercial snakeheads, and different individuals of the paternal maternal line are mated to breed commercial snakeheads. More than 150 thousands of high-quality snakehead fry can be supplied to the society every year, and also 10 thousands of parents and parents can be specially supplied.

The specific snakehead breeding method comprises the following steps:

(1) and (5) parent selection and cultivation. Selecting 3-5 snakehead geographical populations with space distance over 200 kilometers and natural growth as parents. The selected individual has obvious snakehead body surface characteristics, and the anatomical structures of other aspects have the characteristics of conventional snakehead varieties, so that the body is healthy, disease-free and injury-free; the individuals are required to be selected to be 2 winter years old, and the body weight reaches more than 2 kilograms.

(2) The breeding method of the male and female line comprises the following steps:

(2.1) father line breeding, taking growth speed and bait coefficient as selection indexes, requiring that the overwintering weight in the current year reaches more than 200 g, the average weight at the end of 10 months in the 2 nd year reaches more than 1500 g, the bait coefficient is within 1.35, and the individuals which can not meet the requirements can not be used as seeds. After 3-4 generations of breeding, the growth advantage character index is fixed, namely the growth speed and the bait coefficient.

And (2.2) breeding the female line, and selecting by taking the number of eggs laid, the fertility rate and the hatchability reproductive performance as main selection indexes and considering the growth performance. The amount of eggs per kilogram is required to reach 20000 eggs, the fertilization rate reaches 85%, the hatching rate reaches 90%, the survival rate of fish fries reaches more than 80%, the overwintering weight in the current year reaches 150 g, and the average weight at the end of 10 months in the 2 nd year reaches more than 1200 g. The individual is used as the parent strain when the index is reached, and the individual which cannot be reached is eliminated. After 3-4 generations of breeding, the breeding advantage character index is fixed, namely the breeding performance of egg laying number, fertility rate and hatchability.

(3) And (5) commodity hybridization progeny production. The bred maternal line individuals are used as female parents, the bred paternal line individuals are used as male parents, and filial generation of the hybridized commodity is produced.

Meanwhile, the obtained data is compared with the common snakehead, and statistical analysis is carried out on the data by using statistical software. The results are shown in the table below, and the differences of the new breeding variety (strain) and common snakeheads in 1-month age, 5-month age and bait coefficient are obvious, and the weight difference of the new breeding variety (strain) on the market at 18-month age is extremely obvious.

The growth performance of the breeding variety (strain) of the epiophyta obscura is compared with that of the common ophyta obscura

Note: comparison of P <0.05 in the same row indicates significant difference, P <0.01 indicates significant difference, and P >0.05 indicates insignificant difference, as follows.

Claims (1)

1. A method for breeding commercial snakeheads is characterized by comprising the following steps: the method comprises the following steps:

(1) parent selection and cultivation, wherein snakeheads from different geographical populations are used as breeding materials; specifically, 3-5 snakehead geographical populations which naturally grow and have a spatial distance of more than 200 kilometers are selected; the individual has the body surface characteristics of the snakeheads, the other aspects of the individual contain anatomical structures and have the conventional snakehead variety characteristics, and the individuals are all snakeheads with the winter age and the body weight of more than 2 kilograms as parents;

(2) the parent and maternal line breeding method comprises the following steps:

(2.1) carrying out paternal line breeding, wherein the growth speed and the bait coefficient are used as selection indexes; the overwintering weight of the snakeheads in the current year is required to reach more than 200 g, the average weight of the snakeheads in the 10 th month in the 2 nd year is required to reach more than 1500 g, and the bait coefficient is within 1.35; through breeding of 3-4 generations, the growth advantage character index is fixed; the growth dominance character indexes refer to growth speed and bait coefficient;

(2.2) breeding the mother line, and selecting by taking the number of eggs laid, the fertility rate and the hatchability reproductive performance as selection indexes and considering the growth performance; when breeding a mother line, the amount of eggs per kilogram is required to reach 20000 grains, the fertility rate reaches 85%, the hatchability reaches 90%, the survival rate of fish fries reaches more than 80%, the overwintering weight in the current year reaches 150 g, and the average weight at the end of 10 months in the 2 nd year reaches more than 1200 g; breeding for 3-4 generations to fix the indexes of the propagation advantage characters; the breeding dominant character index refers to the number of eggs laid, fertility rate and hatchability breeding performance;

(3) and (3) producing commodity filial generation, namely, breeding the female parent with the female line individual and breeding the male parent with the male line individual as the male parent to produce the commodity filial generation.

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