TWI418297B - Artificial Induction of the Natural Transformation of Grouper Fish and Its Application - Google Patents

Description

Artificial induction method for promoting natural transformation of grouper and its application

The present invention relates to a method for the transformation of fish, and in particular to a method for the natural transformation of a grouper in an environment.

According to the grouper, the grouper is a kind of marine fish. There are more than 400 species in the world, distributed in tropical and subtropical seas. It is a high economic value fish in food fish. Due to the rise of the grouper breeding industry, the source of fry supply is lacking, which drives the artificial breeding of grouper. However, the main difficulty encountered in the artificial propagation of groupers is the lack of sufficient sources of male fish.

In addition, the grouper belongs to a hermaphrodite and single male type of male and female males, meaning that male groupers must be transformed from the female fish of adult fish, such as the currently farmed maraba grouper and spotted grouper. However, since the mature male fish is too large and difficult to capture, it is not conducive to the artificial propagation work. Therefore, the artificial transformation of the grouper has been carried out for many years.

The most common way used in the past was to use the effects of exogenous males to induce sexual transformation of females. For example, Chen (1977) promoted denaturation by oral administration of oral steroids ( E.tauvina ) by methyl steroids (Oral administratipn). Success; Yeh et al. (1986; 1987) conducted a series of transformation-promoting experiments for the Maraba grouper and the grouper ( E.fario ). In addition to the method of using oral hormones, there are also methods such as intramuscular injection or implantation (Yeh et al., 1988; 1989; Tan-Fermin et al., 1994).

However, the use of the above methods often causes the problem of how many doses are used, and the continuous treatment time is long. Moreover, the male and female fish must be separately reared, so that many problems are caused in the cultivation and management of the cultured fish. In addition, factors such as fish age, fish size, hormone type, granule production method, fish gonad development and absorption mode need to be considered. At present, there is still no standardized artificial induced grouper transformation technology that can be followed, which leads to the increase of females. The difficulty of fish transformation.

The main object of the present invention is to provide a method for artificially promoting the natural transformation of grouper fish, which does not require the use of hormones to reduce the effect on the operation of the fish, and meets the economic benefits of the fish management.

A second object of the present invention is to provide a method for artificially inducing the natural transformation of grouper, which is simple in operation and short in time to save the production cost of artificial propagation.

Another object of the present invention is to provide a method for artificially inducing the natural transformation of grouper fish, which can avoid the use of exogenous androgens and affect the endocrine changes of fish, and further avoid the phenomenon of reversal of sexual transformation.

In order to achieve the foregoing objectives, the present invention provides a method for artificially inducing the natural transformation of grouper fish and its application, which utilizes the principle of environmental regulation factors (community control) to induce and promote the natural occurrence of a female grouper. Sexual transformation, the method is to select a healthy female zebrafish that has matured at a predetermined time before the breeding season, and at least 4 female zebrafish are stocked in an environment of 1000 m ^{3 of} water, and the female grouper is naturally in the water environment. After the sexual transformation into a male grouper, the male grouper that has undergone the transformation can be removed, and then a female fish is added to maintain the stocking density, which can once again cause a female grouper to undergo a sexual transformation.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a preferred embodiment of the present invention will be described with reference to the accompanying drawings.

Referring to the first figure, the method for artificially inducing the natural transformation of the grouper in the present invention comprises the following steps: Step 101: Before the grouper breeding season, select one of the female groupers whose gonads have matured.

Step 102: The at least four female groupers are stocked in an environment of 1000 m ^{3 of} water, and one of the female groupers is sexually transformed into a male grouper.

The above method of the present invention utilizes the principle of regulating environmental factors - social control to induce the natural transformation of groupers, and no exogenous males are required in the process of sexual transformation, such as Hor. Mongolian does not affect the endocrine changes of the female grouper, so it does not cause the adverse effect of the reversal of sexual transformation. In addition, because there is no need to use hormones at all, reduce the pressure on the fish farming (Stress) The effect is in line with the economic benefits of the management of the fish, and it will not cause adverse effects on the environment due to improper dose control of the hormones, and the internal residues of the upper organisms in the food chain to prevent damage to the ecology.

In the method of the present invention, the time for selecting the female grouper in step 101 is at least 6 months before the grouper breeding season or before the grouper breeding season, so that the female grouper has sufficient time to undergo a sexual transition.

The method of the present invention further comprises the step 103 of removing the male grouper that has undergone a transition from the environment.

The method of the present invention, wherein the stocking density is 4 to 5 female grouper / 1000 m ³ water body is a preferred environment.

For the male and female grouper, the female fish is normal body color and small in size. During the breeding season, the abdomen expands (because the ovary is filled with the abdominal cavity); the male fish has a pale body and a large body. During the breeding season, The abdomen is normal or slightly thin.

The above method of the present invention can be applied to all grouped fishes of the hermaphroditic grouper or single male type, which are Cromileptes , Variola , and Haze. ( Aethaloperca ), Gracila , Cephalopholis , Anyperodon , Triso , Epinephelus , Saloptia or Hedgehog Genus ( Plectropomus ) and other species of the subfamily fish.

101‧‧‧Before the grouper breeding season, choose one of the female gonads that has matured

102‧‧‧Retain at least 4 female species of the grouper in an environment of 1000 m ^{3 of} water

103‧‧‧Removing the male grouper that has undergone a sexual transition from the environment

The first figure is a flow chart of a method of a preferred embodiment of the present invention.

101‧‧‧Before the grouper breeding season, choose one of the female gonads that has matured

102‧‧‧Retain at least 4 female species of the grouper in an environment of 1000 m ^{3 of} water

103‧‧‧Removing the male grouper that has undergone a sexual transition from the environment

Claims (4)

An artificial induction method of promoting grouper naturalness transition of which includes the following steps: A prior grouper breeding season, selected gonad have reached mature female grouper; B stocking density of 0.004 / m ³ ~ 0.02 tail / m.. ^In the density range of ³ , the female grouper is stocked in a water environment; wherein the grouper is selected from the group consisting of hermaphroditic and single male type of first male and female grouper. The method for artificially promoting the natural transformation of grouper according to the first aspect of the patent application, wherein the time of selecting the female grouper in step A is at least 6 months before the grouper breeding season. The method for artificially inducing the natural transformation of the grouper according to the first or second aspect of the patent application further comprises the step C; and the step C: removing the male grouper that has undergone the transformation from the environment. A method for artificially inducing a natural transformation of a grouper according to the first aspect of the patent application, wherein the grouper is selected from the group consisting of Cromileptes , Variola , Aethaloperca , and teeth. Gracila , Cephalopholis , Anyperodon , Triso , Epinephelus , Saloptia , and Plectropomus A group of species of the subfamily.