A breeding method for improving the survival rate of bullfrogs during metamorphosis

Abstract

The present invention discloses a breeding method for improving the survival rate of bullfrogs during metamorphosis, and belongs to the technical field of bullfrog tadpole cultivation. The present invention provides a breeding method for improving the survival rate of bullfrogs during metamorphosis, including the steps of adding a biofloc culture medium into a feeding water body and mixing citral with feed for young frogs after metamorphosis, wherein the components of the biofloc culture medium include edible glucose, brown sugar, shrimp powder and concentrated bacillus powder; according to the mass ratio, the mixing mass ratio of edible glucose: brown sugar: shrimp powder: concentrated bacillus powder is 5:5:5:1. The present invention utilizes the combination of biofloc technology to cultivate bullfrog tadpoles and mixing plant-based additives with feed to feed young frogs after metamorphosis, providing a more efficient and sustainable solution for the healthy breeding of bullfrogs, further enhancing the physical fitness of bullfrogs, and achieving the purpose of improving the survival rate of bullfrogs during metamorphosis.

Description

Technical Field

[0001] The invention relates to the technical field of bullfrog tadpole cultivation and breeding, in particular to a breeding method for improving the survival rate of bullfrogs in metamorphosis period. Background Art

[0002] Bullfrog (Rana catesbeiana) farming has become a high-value farming species due to its rapid growth rate, short breeding cycle and strong environmental adaptability. It is widely distributed in Guangdong, Guangxi, Hunan and other places. However, bullfrogs are very sensitive to environmental changes during the seedling stage. Their survival rate and physical fitness during the metamorphosis period directly determine the growth effect in the later stage. Therefore, it is crucial to ensure that bullfrogs can smoothly transform from tadpoles to froglets during the seedling stage.

[0003] Water quality management and nutritional supplementation during the breeding process have an important impact on the smooth transformation of bullfrogs from tadpoles to froglets during this breeding stage. In the traditional pond enclosure breeding system, a large amount of water is discharged and replaced every day to remove toxic substances such as ammonia nitrogen and nitrite in the water body. This method maintains the water quality of the pond in the short term, but the discharged tail water often contains a large amount of untreated organic matter, nitrogen, phosphorus and other nutrients and residual pathogens. The direct discharge of tail water will have many adverse effects on the surrounding ecological environment. In addition, the metamorphosis process of bullfrogs is a critical stage in which energy and nutritional requirements change dramatically. Tadpoles will fast during this process, mainly due to the reconstruction of the digestive system and the adjustment of physiological needs. As tadpoles gradually transform into adult frogs, the metabolic pattern in the body changes significantly. At this time, stopping feeding makes it difficult for them to obtain sufficient nutritional reserves. In addition, their physical fitness has not yet recovered, resulting in generally poor immunity and disease resistance. Therefore, it is of great significance to provide a breeding method that can improve the survival rate of bullfrogs during metamorphosis. Summary of the invention

[0004] The purpose of the present invention is to provide a breeding method for improving the survival rate of bullfrogs during metamorphosis, so as to solve the problems existing in the above-mentioned prior art. The breeding method provided by the present invention can cultivate and enhance the physical fitness of bullfrogs, thereby achieving the purpose of improving the survival rate of bullfrogs during metamorphosis.

[0005] To achieve the above object, the present invention provides the following solutions:

[0006] Technical solution 1: A breeding method for improving the survival rate of bullfrogs during metamorphosis, comprising the steps of adding biofloc culture medium into the breeding water body and feeding the metamorphosed young frogs with citral mixed feed, wherein the components of the biofloc culture medium include edible glucose, brown sugar, shrimp powder and concentrated Bacillus powder.

[0007] Furthermore, in terms of mass ratio, the mixing mass ratio of edible glucose: brown sugar: shrimp powder: concentrated bacillus powder is 5:5:5:1.

[0008] Furthermore, the feeding time of the citral is one month.

[0009] Furthermore, the effective viable count of the concentrated Bacillus powder is 10 10 CFU / g.

[0010] Furthermore, the biofloc culture medium is added to the breeding water body 7 days before the release of bullfrog tadpole seedlings, and the biofloc culture medium is added to the disinfected breeding water body every day.

[0011] The present invention discloses the following technical effects:

[0012] The biological flocs provided by the present invention form natural "flocs" in the water body, which can decompose harmful substances such as ammonia nitrogen, reduce the risk of frequent water changes and pathogen invasion during the tadpole cultivation period, and there is no aquaculture tailwater discharge during the tadpole to frog breeding process. During the breeding period, toxic nitrogen compounds such as ammonia nitrogen in the water body can be converted into flocs in the breeding water body for tadpoles. The young frogs after metamorphosis are weak and susceptible to diseases. The essential oils in the mixing ingredients provided by the present invention can not only enhance the immunity of the young frogs after metamorphosis and relieve stress reactions, but also promote the health of intestinal flora and make up for the malnutrition during the metamorphosis period. The present invention uses the combination of biological floc technology to cultivate bullfrog tadpoles and plant-based additives to mix and feed the young frogs after metamorphosis, which provides a more efficient and sustainable solution for the healthy breeding of bullfrogs. This innovative combination is more adaptable than traditional methods, and is particularly suitable for the metamorphosis period and the initial breeding stage of bullfrogs, providing excellent water quality regulation and health promotion effects, achieving the purpose of cultivating and enhancing the physical fitness of bullfrogs, and ultimately improving the survival rate of bullfrogs during metamorphosis. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0014] Figure 1 This is the situation of bullfrog tadpoles cultured in biofloc in Example 1 metamorphosing into small four-legged frogs. DETAILED DESCRIPTION

[0015] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as limiting the present invention, but should be understood as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0016] It should be understood that the terms described in the present invention are only for describing a particular embodiment and are not intended to limit the present invention. In addition, for the numerical range in the present invention, it should be understood that each intermediate value between the upper and lower limits of the scope is also specifically disclosed. The intermediate value in any stated value or stated range, and each smaller range between any other stated value or intermediate value in the described range is also included in the present invention. The upper and lower limits of these smaller ranges can be independently included or excluded in the scope.

[0017] Unless otherwise indicated, all technical and scientific terms used herein have the same meanings as those generally understood by those skilled in the art. Although the present invention describes only preferred methods and materials, any methods and materials similar or equivalent to those described herein may also be used in the implementation or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials associated with the documents. In the event of a conflict with any incorporated document, the content of this specification shall prevail.

[0018] It will be apparent to those skilled in the art that various modifications and variations may be made to the specific embodiments of the present invention description without departing from the scope or spirit of the present invention. Other embodiments derived from the present invention description will be apparent to the skilled artisan. The present invention description and examples are exemplary only.

[0019] The words “include,” “including,” “have,” “contain,” etc. used in this document are open-ended terms, meaning including but not limited to.

[0020] Example 1

[0021] A breeding method for improving the survival rate of bullfrogs during metamorphosis

[0022] (1) Preparation of breeding system

[0023] Preparation of supporting aquaculture systems: including oxygenation system, water push system, etc. The aquaculture cement pool is 64m long, 8m wide, 2.5m high and 1.2m deep;

[0024] Disinfection of aquaculture water: The aquaculture water is river water, which is filtered by a filter cotton bag (extracted by a submersible pump, and a filter cotton bag is tied to the water pipe mouth). The aquaculture pond is 1m deep. Use potassium persulfate (50% concentration) 2g / cubic water body, dissolve it and then sprinkle it. Disinfect for more than 6 hours and use it after aeration for 12 hours.

[0025] Seven days before stocking bullfrog tadpole seedlings, biofloc culture medium (mixed mass ratio of edible glucose: brown sugar: shrimp powder: concentrated Bacillus powder is 5:5:5:1) is added to the disinfected breeding water every day. The effective viable count of concentrated Bacillus powder is 1010 CFU / g, concentrated Bacillus powder was purchased from Guangzhou Xinhai Lisheng Biotechnology Co., Ltd., and shrimp powder was purchased from Guangdong Zhanjiang Zhengda Aquatic Products Co., Ltd. A biofloc culture medium made by mixing 5kg of edible glucose, 5kg of brown sugar, 5kg of shrimp powder, and 1kg of concentrated Bacillus powder was dissolved in 50kg of breeding water, 0.1L / m 3 The water is splashed throughout the pond for 7 consecutive days.

[0026] (2) Seedling placement and breeding density

[0027] Seedling release method: Before the packaged tadpole seedlings enter the production workshop, they must be disinfected with 3ppm povidone iodine solution on the outer bag before entering the breeding pond. The temperature difference is controlled within 1°C when releasing the seedlings, and the temperature difference is controlled within 3°C in 24 hours. In order to make the tadpole seedlings adapt to the water quality environment of the nursery pond as soon as possible, the bag must be floated before opening, and the bag containing the tadpole seedlings must be floated on the water surface of the breeding pond for 30 minutes to balance the temperature inside and outside the bag. Then open the bag and slowly add pond water to the bag until it overflows, so that the tadpole seedlings gradually enter the water. 1 hour before releasing the seedlings, sprinkle 0.5g of Vc detoxification stress spirit (Guangzhou Xinhailisheng Biotechnology Co., Ltd.) per cubic meter of breeding water to prevent tadpole seedlings from stress.

[0028] Density of stocking seedlings: Tadpoles are small round heads of tadpoles 7 days after embryonic development, with a density of 1000 / m 3 .

[0029] (3) Daily management

[0030] The bullfrog tadpoles were reared until they metamorphosed into small four-legged frogs, wherein no water change was performed during the entire rearing process in step (2). The dissolved oxygen content of the water was ensured to be no less than 5 mg / L, and the water was lightly aerated within 12 hours after stocking, and then moderately and evenly aerated (30-50 mL / s); light: natural light; water temperature: 25-30°C; pH 7.0-8.5. The shrimp feed (sinking feed, purchased from Guangdong Zhanjiang Zhengda Aquatic Products Co., Ltd.) was fed three times a day (6:30, 12:00 and 19:00).

[0031] After about 40 days of breeding, a special bullfrog breeding float is set up in the breeding water body, with an area not exceeding 80% of the breeding water surface, for the bullfrog tadpoles to metamorphose into small four-legged (see Figure 1 ) before use.

[0032] The metamorphosed young frogs were fed with 4 mg / L citral (purchased from Sigma-Aldrich (Shanghai) Trading Co., Ltd.) mixed with feed (bullfrog feed (floating feed, purchased from Foshan Shunde Wanghai Feed Industrial Co., Ltd.)) for one month.

[0033] Comparative Example 1

[0034] The difference between this comparative example and Example 1 is:

[0035] (1) Seven days before stocking bullfrog tadpole seedlings, do not add biofloc culture medium (the mass ratio of edible glucose: brown sugar: shrimp powder: concentrated Bacillus powder is 5:5:5:1) to the disinfected breeding water. Instead, replace the water in the pond every day, with the water change frequency once a day, and the water change volume each time is 1 / 2 of the total water volume in the pond, and the temperature difference between the new and old water is controlled within 1-2°C;

[0036] (2) After metamorphosis, the young frogs were not fed with 4 mg / L citral (purchased from Sigma-Aldrich (Shanghai) Trading Co., Ltd.) mixed with bullfrog feed (floating feed, purchased from Foshan Shunde Wanghai Feed Industrial Co., Ltd.) for one month.

[0037] The remaining culture conditions were the same as in Example 1.

[0038] The differences in the bullfrogs and their environments under the two breeding methods of Example 1 and Comparative Example 1 are statistically analyzed, as shown in Tables 1 to 3.

[0039] Table 1

[0040] Group <![CDATA[Ammonia nitrogen / (mg·L -1 )]]> <![CDATA[Nitrite / (mg·L -1 )]]> pH Water change amount Comparative Example 1 1.66-5.65 0.1-2 6.87-9.3 1 / 2 of the total water volume Example 1 0.01-1 0-0.1 7.5-8.5 No water change

[0041] Table 2

[0042] Group Metamorphosis time (days) Transformation success rate (%) Comparative Example 1 80 50 Example 1 50 92

[0043] Table 3

[0044]

[0045]

[0046] As can be seen from Tables 1 to 3, compared with the breeding mode of Comparative Example 1, the advantages of the biological floc cultivation provided by the present invention are as follows: no water change is required during the entire seedling raising process, the water quality is stable, the metamorphosis time of bullfrog tadpoles is shortened, and the metamorphosis success rate is high. After breeding using the biological floc provided by the present invention, the final body weight increases, and the breeding benefits and efficiency are improved. Moreover, the present invention uses essential oils to mix the feed for one month after metamorphosis, which can significantly improve the growth performance of young frogs, improve the intestinal structure and digestive function compared with Comparative Example 1. In short, the breeding method provided by the present invention jointly improves the survival rate of bullfrogs during metamorphosis.

[0047] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A breeding method for improving the survival rate of bullfrogs during metamorphosis, characterized in that: The method comprises the steps of adding a biofloc culture medium into a breeding water body and feeding the metamorphosed young frogs with citral mixed feed, wherein the components of the biofloc culture medium include edible glucose, brown sugar, shrimp powder and concentrated bacillus powder; the mixing mass ratio of the edible glucose: brown sugar: shrimp powder: concentrated bacillus powder is 5:5:5:1 according to the mass ratio; the feeding time of the citral is one month; the effective viable bacteria count of the concentrated bacillus powder is 10 10 CFU / g; the biofloc culture medium is added to the breeding water body 7 days before stocking bullfrog tadpole seedlings, and the biofloc culture medium is added to the disinfected breeding water body every day.

Images