Staged temperature control fly pupa preservation method and application

Abstract

The invention provides a staged temperature control fly pupa preservation method and application, and belongs to the technical field of insect preservation. The metabolic process of the fly pupae is effectively delayed in the low-temperature stage, and premature eclosion and energy consumption of the fly pupae are avoided. Then, the physiological activity of the fly pupae is gradually improved in the temperature control environment of 10 DEG C and 15 DEG C, and the effects of recovering and promoting eclosion are achieved. Through staged temperature control preservation, the preservation time can be prolonged, the preservation and activity recovery requirements of the fly pupae can be balanced, stress injury possibly caused by direct temperature rise is avoided, the preservation period of the fly pupae is effectively prolonged, and the problems that in an existing preservation method, the survival rate of the fly pupae is low, and the eclosion rate attenuation is fast are solved. And the stability and efficiency of fly maggot protein production are ensured. Moreover, a simple, convenient, economical and efficient solution is provided for remote transportation of the fly pupae, and powerful support is provided for balanced and sustainable supply of feed protein resources in the market.

Description

Technical Field

[0001] The present invention relates to the technical field of insect preservation, and in particular to a stage-by-stage temperature-controlled fly pupa preservation method and application. Background Art

[0002] With the continuous expansion of livestock and poultry farming, the treatment and utilization of solid waste has become a critical issue that needs to be addressed. Current practices primarily rely on composting, which, while achieving a certain degree of resource utilization, remains primarily limited to the low-efficiency, single-use organic fertilizer production stage. According to incomplete statistics, over 40% of livestock and poultry manure remains underutilized, creating a significant environmental burden. Against this backdrop, fly maggot bioconversion technology stands out due to its high organic matter conversion efficiency.

[0003] As living standards improve, demand for high-quality aquatic products is growing, driving the continuous expansion of the aquaculture industry. High-quality protein feed, particularly fishmeal, is a key nutrient essential for the growth and development of aquatic animals, and demand is rapidly increasing. However, global fishmeal resources are limited. In recent years, the decline of marine fishery resources and fishing restrictions have led to an increasingly tight supply, severely constraining the development of the aquaculture industry. Therefore, finding new, high-quality alternatives to fishmeal has become a top priority for the aquaculture industry to overcome development bottlenecks.

[0004] Insects are considered a potential alternative to fishmeal protein due to their high bioconversion rates, rapid reproduction rates, and high protein content. Maggot protein is particularly prominent, being rich in essential amino acids for animal growth and development, as well as vitamins and a variety of bioactive substances. Studies have shown that adding maggot protein to livestock and aquatic animal feed can effectively enhance animal immunity, reduce antibiotic use, and ensure the quality and safety of agricultural products at the source. More importantly, maggots are highly efficient bioconverters of livestock and poultry solid waste. The bioconversion of livestock and poultry waste by maggots not only produces high-value maggot protein but also generates high-quality organic fertilizer, effectively transforming waste into valuable resources and establishing an ecologically sustainable industrial chain.

[0005] However, to achieve large-scale development of the fly maggot protein industry, fly pupa preservation technology has become a key constraint. In the fly maggot breeding process, the fly pupa stage is an important link between larvae and adults, and its preservation effect directly affects the continuity and production efficiency of fly maggot breeding. At present, the low-temperature preservation method commonly used in the industry has many disadvantages. On the one hand, the survival rate and emergence rate of fly pupae in low-temperature environments fluctuate greatly and are difficult to control stably, which makes it impossible to guarantee the output and quality of subsequent fly maggot breeding; on the other hand, long-term or single low-temperature treatment can easily cause the growth of fly pupae to stagnate, or even cause death.

[0006] Therefore, there is an urgent need for a preservation method that can improve the survival rate and emergence rate of fly pupae. Summary of the Invention

[0007] The purpose of the present invention is to provide a staged temperature-controlled fly pupa preservation method and application, which can significantly improve the survival rate and emergence rate of fly pupae by controlling the preservation temperature and preservation time, and provide technical support for the large-scale application of fly maggot protein.

[0008] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0009] The present invention provides a staged temperature-controlled fly pupae preservation method, comprising the following steps:

[0010] (1) Preserving the fly pupae in a low-temperature environment;

[0011] (2) taking the fly pupae stored at low temperature in step (1) and placing them at 9-11° C. for a second storage;

[0012] (3) taking the fly pupae after the second preservation in step (2) and placing them at 14-16° C. for a third preservation;

[0013] (4) The fly pupae after the third preservation in step (3) are subjected to eclosion treatment.

[0014] Preferably, in step (1), the fly pupae are fly pupae that are initialized for 1 to 3 days.

[0015] Preferably, in step (1), the temperature of the low-temperature environment is 6 to 10° C., and the preservation time is 0 to 30 days.

[0016] Preferably, the temperature of the low-temperature environment is 6° C., and the storage time is 0 to 30 days.

[0017] Preferably, the temperature of the low temperature environment is 10°C and the storage time is 0 to 20 days.

[0018] Preferably, in step (2), the second preservation time is 1 to 3 days.

[0019] Preferably, in step (3), the third preservation time is 1 to 3 days.

[0020] Preferably, in step (4), the eclosion temperature is 20-26°C and the humidity is 60-80%.

[0021] The present invention also provides an application of a staged temperature-controlled fly pupa preservation method in the large-scale production of fly maggot protein.

[0022] The beneficial effects of the present invention compared with the prior art are:

[0023] The present invention effectively delays the metabolic process of fly pupae through the low-temperature stage, avoiding premature emergence and energy consumption of fly pupae. Subsequently, by gradually improving the physiological activity of fly pupae under a temperature-controlled environment of 10°C and 15°C, the effect of recovery and promotion of emergence is achieved. Through staged temperature-controlled preservation, it is possible to balance the preservation and activity recovery requirements of fly pupae while extending the preservation time, avoiding stress damage that may be caused by direct temperature increase, effectively extending the storage period of fly pupae, and solving the problems of low survival rate of fly pupae and rapid decay of emergence rate in existing preservation methods, ensuring the stability and efficiency of fly maggot protein production, and providing technical support for the large-scale application of fly maggot protein. It also provides a simple, economical and efficient solution for the long-distance transportation of fly pupae, and provides strong support for the balance and sustainable supply of market feed protein resources. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. 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 any creative work.

[0025] Figure 1 The following is a comparison of the emergence rates of fly pupae stored at 6°C in stages and at a single temperature of 6°C in Example 1 and Comparative Example 1;

[0026] Figure 2 The following is a comparison of the emergence rates of fly pupae stored at 10°C in stages and at a single temperature of 10°C in Example 2 of the present invention and Comparative Example 2;

[0027] Figure 3 The emergence of fly pupae under different temperature conditions and different storage times in Test Example 1 of the present invention;

[0028] Figure 4 This is the effect of different humidity in the emergence chamber on the emergence rate of fly pupae in Test Example 2 of the present invention. DETAILED DESCRIPTION

[0029] 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 rather as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0030] It should be understood that the terms described herein are intended only to describe particular embodiments and are not intended to limit the present invention. In addition, for numerical ranges herein, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Each smaller range between any intermediate value within a stated value or stated range and any other stated value or intermediate value within the stated range is also encompassed by the present invention. The upper and lower limits of these smaller ranges may be independently included or excluded within the scope.

[0031] Unless otherwise indicated, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art. Although only preferred methods and materials are described herein, any methods and materials similar or equivalent to those described herein may also be used in the practice 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 any conflict with any incorporated document, the contents of this specification shall prevail.

[0032] It will be apparent to those skilled in the art that various modifications and variations may be made to the specific embodiments described herein without departing from the scope or spirit of the invention. Other embodiments will be apparent to those skilled in the art from the description of the invention. The description and examples are intended to be exemplary only.

[0033] The words “include,” “including,” “have,” “contain,” etc. used in this document are open-ended terms, meaning including but not limited to.

[0034] Example 1

[0035] Example 1 of the present invention provides a staged temperature-controlled fly pupae preservation method, the specific steps of which are as follows:

[0036] (1) The first stage: the fly pupae on the first day of pupation at 25°C were placed in a large fresh-keeping box (27×19×9.5 cm) with a stacking thickness of about 5 cm. The fresh-keeping box was covered and stored in a low-temperature environment of 6°C (divided into 6 treatment groups A to F, group A was stored for 6 days, and groups B to F were stored for 10 days on the basis of group A's 6 days) to delay their physiological activities;

[0037] (2) The second stage: placing the fresh-keeping box containing the fly pupae in step (1) at 10°C and 15°C in turn, and preserving them at each temperature for 2 days to restore the physiological activity of the fly pupae;

[0038] (3) The third stage: The fly pupae from step (2) were transferred to a constant temperature incubator at 25°C and humidity controlled at 80% for eclosion treatment. The eclosion rate was calculated. Three parallel replicates were set for each treatment group. The results are shown in Figure 2. Figure 1 shown.

[0039] Comparative Example 1

[0040] Comparative Example 1 of the present invention adopts a single temperature preservation method of 6°C to preserve fly pupae, and the specific steps are as follows:

[0041] Take the fly pupae on the first day of pupation at 25℃ and put them into a large fresh-keeping box (27×19×9.5cm) with a stacking thickness of 5cm. After the fresh-keeping box is closed, place it directly in a 6℃ environment for storage. Samples are taken every 7 days and the fly pupae samples are placed in a constant temperature incubator at 25℃ and 80% humidity for eclosion. The eclosion rate is calculated. Three parallel replicates are set for each treatment group. The results are as follows Figure 1 shown.

[0042] Figure 1 The results showed that the initial emergence rates of the pupae using the staged temperature-controlled storage method and the single 6°C storage method were 97.27% and 93.45%, respectively. The emergence rate gradually decreased with prolonged storage. In the single 6°C storage group, the emergence rate dropped by 15.31% after 7 days of storage; by 14 days, it dropped to 37.09%; by 21 days, it dropped to 16.89%; and by 31 days, it was close to 0%.

[0043] In contrast, the emergence rate of the fly pupae in the staged temperature-controlled fly pupae preservation group of the present invention decreased by only 1.19% after 10 days of preservation; after 20 days of preservation, the emergence rate stabilized at 81.16%; after 30 days of preservation, the emergence rate dropped to 34.79%. When the preservation time was extended to 40 days, the emergence rate dropped to below 5%, and as time went on, the fly pupae no longer emerged. The results show that the staged temperature control method of the present invention can effectively activate the fly pupae in low-temperature storage by slowly increasing the temperature, significantly improving their emergence rate.

[0044] Example 2

[0045] Example 2 of the present invention provides a staged temperature-controlled fly pupae preservation method, the specific steps of which are as follows:

[0046] (1) The first stage: the fly pupae on the first day of pupation at 25°C were placed in a large fresh-keeping box (27×19×9.5 cm) with a stacking thickness of about 5 cm. The fresh-keeping box was covered and stored in a low-temperature environment of 10°C (divided into 6 treatment groups A to F, group A was stored for 6 days, and groups B to F were stored for 10 days on the basis of group A's 6 days) to delay their physiological activities;

[0047] (2) The second stage: placing the fresh-keeping box in which the fly pupae were stored in step (1) at 15° C. for 2 days to restore the physiological activity of the fly pupae;

[0048] (3) The third stage: The fly pupae from step (2) were transferred to a constant temperature incubator at 25°C and humidity controlled at 80% for eclosion treatment. The eclosion rate was calculated. Three parallel replicates were set for each treatment group. The results are shown in Figure 2. Figure 2 shown.

[0049] Comparative Example 2

[0050] Comparative Example 2 of the present invention adopts a single temperature preservation method of 10°C to preserve fly pupae, and the specific steps are as follows:

[0051] Take the fly pupae on the first day of pupation at 25℃ and put them into a large fresh-keeping box (27×19×9.5cm) with a stacking thickness of 5cm. After the fresh-keeping box is closed, place it directly in a 10℃ environment for storage. Samples are taken every 7 days and the fly pupae samples are placed in a constant temperature incubator at 25℃ and 80% humidity for eclosion. The eclosion rate is calculated. Three parallel replicates are set for each treatment group. The results are as follows Figure 2 shown.

[0052] Depend on Figure 2 The results show that the initial emergence rates of fly pupae stored at 10°C in stages and at a single temperature of 10°C were 97.27% and 93.25%, respectively. The emergence rates gradually decreased with the extension of storage time. At 14 days of storage at a single temperature, the emergence rate of fly pupae dropped to 47.78%, below 50%. However, when stored at staged temperature, the emergence rate remained at 93.19% after 10 days, then dropped to 69.74% after 20 days and 46.66% after 30 days.

[0053] Example 3

[0054] Example 3 of the present invention provides a staged temperature-controlled fly pupae preservation method, the specific steps of which are as follows:

[0055] (1) The first stage: the fly pupae on the second day of pupation at 25°C were placed in a large fresh-keeping box (27×19×9.5 cm) with a stacking thickness of about 5 cm. The fresh-keeping box was covered and stored in a low-temperature environment of 8°C for 20 days to delay their physiological activities.

[0056] (2) The second stage: placing the fresh-keeping box containing the fly pupae in step (1) at 9°C and 16°C in turn, and preserving them at each temperature for 1 day to restore the physiological activity of the fly pupae;

[0057] (3) The third stage: the fly pupae from step (2) are transferred to a constant temperature incubator at 25°C and humidity controlled at 70% for eclosion.

[0058] Example 4

[0059] Example 4 of the present invention provides a staged temperature-controlled fly pupae preservation method, the specific steps of which are as follows:

[0060] (1) The first stage: The fly pupae on the third day of pupation at 25°C were placed in a large fresh-keeping box (27×19×9.5 cm) with a stacking thickness of about 5 cm. The fresh-keeping box was covered and stored in a low-temperature environment of 8°C for 10 days to delay their physiological activities.

[0061] (2) The second stage: placing the fresh-keeping box containing the fly pupae in step (1) at 11°C and 14°C in turn, and preserving them at each temperature for 3 days to restore the physiological activity of the fly pupae;

[0062] (3) The third stage: the fly pupae from step (2) are transferred to a constant temperature incubator at 25°C and humidity controlled at 60% for eclosion.

[0063] Test Example 1

[0064] Test Example 1 of the present invention detected the emergence rate of fly pupae at different storage temperatures, and the specific steps were as follows:

[0065] Four temperature treatment groups were set up: 3°C (refrigerator), 6°C (refrigerator), 10°C (shaking table) and 15°C (shaking table). In each treatment group, the fly pupae 3 days after pupation were placed in a fresh-keeping box. About 300 fly pupae were randomly selected according to the group, and samples were taken every 5 days. Each group of fly pupae was divided into 3 mesh bags. Subsequently, these fly pupae were moved to an environment of 25°C and 60% relative humidity for emergence test. The storage time was 6 to 9 days. The emergence rate of each group of fly pupae was recorded and calculated. The results are as follows: Figure 3 shown.

[0066] Figure 3 It showed that the initial emergence rate was 91.43%. After 5 days of storage, the emergence rate of fly pupae in the 3℃ treatment group dropped to 40.42%; the emergence rate of the 6℃ treatment group was 72.77%; the emergence rates of the 10℃ and 15℃ treatment groups were 87.6% and 87.71%, respectively. After 10 days of storage, the 15℃ treatment group had begun to emerge, with an emergence rate of 82.57%, so the storage was ended early; the emergence rate of the 10℃ treatment group dropped to 58.71%; the emergence rate of the 6℃ treatment group dropped to 43.27%; and the emergence rate of the 3℃ treatment group dropped to 23.55%. After 15 days of storage, slight emergence occurred in the 10℃ treatment group, so the storage process was ended early; the emergence rate of the 6℃ treatment group dropped to 23.06%, and the emergence rate of the 3℃ treatment group dropped to 12.93%. As the storage time was extended to 25 days, the emergence rates of the 3℃ and 7℃ treatment groups dropped to 2.26% and 7.91%, respectively. Figure 1 It can be seen that under the same storage time, the higher the temperature of the storage environment, the higher the feathering rate.

[0067] Test Example 2

[0068] Test Example 2 of the present invention detected the emergence rate of fly pupae at different emergence humidity levels, and the specific steps were as follows:

[0069] The fly pupae treated in step (2) of Example 1 were placed in a constant temperature environment of 25°C and placed under different humidity conditions of 50%, 60%, 70%, and 80% for eclosion. Three parallel samples were set under each humidity condition, and the eclosion of the fly pupae was recorded and the eclosion rate was calculated. The results are as follows: Figure 4 shown.

[0070] Figure 4 It shows that under the condition of 80% humidity, the emergence rate of fly pupae is the highest, about 91.95%, which is significantly higher than other humidity conditions; under the humidity of 60% and 70%, the emergence rate of fly pupae is 89.12% and 89.66% respectively; under the humidity of 50%, the emergence rate of fly pupae is lower, only 87.45%.

[0071] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A method for preserving fly pupae by controlling temperature in stages, characterized in that: The steps include: (1) Preserving the fly pupae in a low-temperature environment; (2) taking the fly pupae stored at low temperature in step (1) and placing them at 9-11° C. for a second storage; (3) taking the fly pupae after the second preservation in step (2) and placing them at 14-16° C. for a third preservation; (4) The fly pupae after the third preservation in step (3) are subjected to eclosion treatment.

2. The method for preserving fly pupae by temperature control in stages according to claim 1, characterized in that: In step (1), the fly pupae are fly pupae that are initialized for 1 to 3 days.

3. The method for preserving fly pupae by temperature control in stages according to claim 1, characterized in that: In step (1), the temperature of the low-temperature environment is 6 to 10° C., and the preservation time is 0 to 30 days.

4. The method for preserving fly pupae by temperature control in stages according to claim 3, characterized in that: The temperature of the low-temperature environment is 6° C., and the preservation time is 0 to 30 days.

5. The method for preserving fly pupae by temperature control in stages according to claim 3, characterized in that: The temperature of the low-temperature environment is 10° C., and the preservation time is 0 to 20 days.

6. The method for preserving fly pupae by temperature control in stages according to claim 1, characterized in that: In step (2), the second preservation time is 1 to 3 days.

7. The method for preserving fly pupae by temperature control in stages according to claim 1, characterized in that: In step (3), the third preservation time is 1 to 3 days.

8. The method for preserving fly pupae by temperature control in stages according to claim 1, characterized in that: In step (4), the eclosion temperature is 20-26° C. and the humidity is 60-80%.

9. Use of the staged temperature-controlled fly pupae preservation method according to any one of claims 1 to 8 in the large-scale production of fly maggot protein.

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