A single-cycle starvation-re-feeding culture method for inducing over-compensatory growth of juvenile qinghe crucian

Abstract

The application discloses a kind of single cycle starvation-re-feeding methods for inducing super-compensatory growth of Qixi crucian carp fry, belonging to the technical field of aquaculture.The method takes healthy, uniform Qixi crucian carp fry as the object of cultivation;In the 28-day cultivation cycle, it is first subjected to continuous 4-day complete starvation treatment, no feed or nutritional substance is fed during the starvation period, then continuous 24-day recovery feeding is carried out, twice a day, and feeding is carried out to apparent satiation, and the starvation-re-feeding process is only performed once in the cultivation cycle.The application can significantly improve the final body length and final body weight of Qixi crucian carp fry while maintaining its stable physiological state, promote muscle fiber proliferation, and induce super-compensatory growth.The method of the application has a clear cycle and is easy to operate, does not require the use of additional exogenous growth promoters, is conducive to reducing feeding days, reducing cultivation costs and waste emissions, and is suitable for feeding management optimization in Qixi crucian carp fry cultivation.

Description

Technical Field

[0001] This invention belongs to the field of aquaculture technology, specifically relating to a single-cycle starvation-refeeding method for inducing supercompensation growth in juvenile crucian carp of the Qihe River. Background Technology

[0002] Qihe crucian carp ( Carassius gibelio Qihe crucian carp (var. Qihe) is a high-quality freshwater economic fish species with local characteristics in Henan Province, my country. It is characterized by its delicious flesh, high nutritional value, and good market acceptance, making it a valuable local aquaculture product. However, in actual farming practices, problems such as extensive feeding and management, low feed utilization efficiency, and high farming costs still exist, limiting its large-scale, efficient, and sustainable development.

[0003] Feed costs are a significant component of aquaculture production costs. While traditional continuous feeding methods can meet the normal growth needs of fish, they are prone to problems such as feed waste, eutrophication, and pollution of aquaculture wastewater. Therefore, establishing a scientific, efficient, and low-cost feeding management model is an important direction for improving the economic benefits of Qihe crucian carp farming and promoting the development of green aquaculture.

[0004] Compensatory growth refers to the biological phenomenon in fish where, after a period of starvation, restricted feeding, or nutritional limitation, the growth rate accelerates upon resuming normal feeding. Depending on the degree of recovery, compensatory growth can be categorized into partial compensation, complete compensation, and supercompensation. Supercompensatory growth, in particular, refers to the phenomenon where the final growth level of fish after resuming feeding exceeds that of the continuously fed control group, demonstrating potential value in reducing feed input, improving feed utilization efficiency, and enhancing aquaculture profitability. However, compensatory growth exhibits significant species specificity and strategy dependence. Too short a starvation period may fail to effectively induce compensatory growth; too long a starvation period may cause physiological damage, oxidative stress, metabolic disorders, or insufficient growth recovery; frequent repeated starvation-refeeding cycles may also exacerbate the body's stress response. Therefore, not all starvation-refeeding programs produce ideal aquaculture results.

[0005] The prior art patent document CN202011229978.7 discloses a nutritional method for maintaining the quality of fatty acids in the muscle of low-fat farmed fish. When flaxseed oil, soybean oil, or sunflower seed oil completely replaces fish oil in the feed, the fish is fed a cyclical diet of 2 weeks of oil-replacing feed followed by 1 week of fish oil feed during the rearing period. After a 1-week fast before harvest, the fish is fed a 4-week diet completely supplemented with fish oil. When rapeseed oil, palm oil, tallow, lard, or chicken oil completely replaces fish oil in the feed, the fish is fed a cyclical diet of 3 weeks of oil-replacing feed followed by 1 week of fish oil feed during the rearing period. After a 1-week fast before harvest, the fish is fed a 4-week diet completely supplemented with fish oil. This method achieves the same effect as continuously feeding fish oil-supplemented feed and solves the problem of declining fatty acid quality in fish meat. Patent document CN201511027471.2 discloses a method for cage culture of bluefin tuna, specifically including the following steps: selection of the culture area; setting up of cages and artificial fishing rods: placing artificial fishing rods, setting up floating frame structures, and hanging 8-14 cages around them; stocking of fish fry: stocking bluefin tuna fry at a density of 0.2-0.8 fish / cubic meter; feeding: implementing periodic starvation followed by feeding, i.e., starving for 2 days, then resuming feeding for 2 days, with feeding time from 2-5 pm, feeding with extruded compound feed for Tongwei fish; this culture method has low input costs, and the cultured bluefin tuna has high oil content and high economic value. However, although the technical solutions of the two patent documents disclosed starvation-refeeding methods for maintaining low-fat aquaculture and cage culture of bluefin tuna, they did not provide a single-cycle starvation-refeeding method for inducing supercompensatory growth in juvenile crucian carp of the Qihe River, nor did they provide any technical guidance on increasing the final body length and final weight of juvenile crucian carp of the Qihe River through specific feeding methods, inducing supercompensatory growth, promoting muscle fiber proliferation, and maintaining a relatively stable physiological state.

[0006] Technical analysis reveals at least the following shortcomings in existing feeding methods for Qihe crucian carp farming: First, continuous feeding relies heavily on feed input, making it difficult to fully utilize the fish's own compensatory growth potential; second, conventional feed restriction or cessation programs lack clear periodic parameters for juvenile Qihe crucian carp, resulting in unstable induction effects; third, unreasonable starvation-refeeding programs may lead to increased oxidative stress and metabolic burden, affecting fish health; and fourth, existing technologies lack feeding management programs for juvenile Qihe crucian carp that simultaneously promote growth, reduce stress, are operable, and have clearly defined mechanisms.

[0007] Therefore, there is an urgent need to establish a starvation-refeeding culture method for juvenile crucian carp in the Qihe River that has a clear cycle, is easy to operate, can stably induce supercompensation growth, and does not cause obvious physiological stress. Summary of the Invention

[0008] The technical problem solved by this invention is to provide a single-cycle starvation-refeeding culture method for inducing supercompensatory growth in juvenile crucian carp of the Qihe River, in order to solve the problems of extensive feeding strategies, high feed costs, unstable supercompensatory growth induction effects, and physiological stress caused by unreasonable feed restriction in the existing Qihe crucian carp culture process.

[0009] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: a single-cycle starvation-refeeding culture method for inducing supercompensatory growth in juvenile crucian carp of the Qihe River, the specific steps of which are as follows: Step S1, Selection and temporary holding of aquaculture targets: 1) Select healthy, undamaged, normally feeding and swimming juvenile Qihe crucian carp of uniform size as the breeding species, preferably 2-month-old juvenile Qihe crucian carp; 2) Place the juvenile crucian carp in the aquaculture system for acclimatization, allowing them to adapt to the aquaculture environment and the extruded compound feed for Tongwei fish. The aquaculture system includes one of the following: indoor tank, recirculating aquaculture system, or pond cage. During the acclimatization period, maintain a stable water environment, control the aquaculture water temperature at 20-24℃, the dissolved oxygen concentration at no less than 5.5 mg / L, and the pH at 7.0-7.5. Regularly remove uneaten feed and feces, and keep the water in an aerated, circulated, or water-changing state. During the acclimatization period, feed the fish with the extruded compound feed for Tongwei fish in the conventional way, twice a day. After the fish's feeding and swimming status stabilizes, they will enter the formal aquaculture cycle. Step S2, complete starvation treatment: After the formal breeding cycle begins, the juvenile crucian carp of Qihe River are subjected to complete starvation treatment for 4 consecutive days. During the complete starvation treatment, no feed or nutrients are provided, and only normal breeding management is carried out, including oxygenation, water quality monitoring, circulation filtration, water exchange, and removal of feces and other pollutants, in order to maintain the stability of the aquatic environment. Step S3, resume feeding process: After four consecutive days of complete starvation, the fish immediately enters a 24-day recovery feeding phase. During the recovery feeding period, the fish is fed with extruded compound feed for Tongwei fish, twice a day, until they appear to be satiated each time. Apparent satiety refers to a significant decrease in the fish's feeding activity, a marked slowdown in feed intake, or the appearance of small amounts of uneaten feed in the water, at which point feeding should be stopped. During the resumption of feeding, uneaten feed should be removed promptly to prevent decomposition and water quality deterioration. The preferred feeding times during the resumption period are 09:30 and 16:30 daily; however, these times can be adjusted to 09:00-10:00 in the morning and 16:00-17:00 in the afternoon, depending on the farm's production and management conditions.

[0010] Step S4, Aquaculture Cycle Control: The complete starvation treatment and the refeeding treatment constitute a complete single-cycle starvation-refeeding rearing process with a total rearing cycle of 28 days, and this starvation-refeeding process is only performed once in a rearing cycle.

[0011] Furthermore, the feed used during the adaptation period and the resumption of feeding is Tongwei fish extruded compound feed.

[0012] Furthermore, the starvation-refeeding rearing method is suitable for healthy, uniform-sized, and rapidly growing Qihe crucian carp juveniles, and is preferably suitable for 2-month-old Qihe crucian carp juveniles.

[0013] Compared with the prior art, the present invention has the following advantages and beneficial effects: 1) This invention establishes a single-cycle starvation-refeeding culture method for juvenile crucian carp in the Qihe River, which involves four consecutive days of complete starvation followed by 24 consecutive days of feeding. Compared with continuous feeding and other starvation-refeeding treatments, this method can significantly increase the terminal body length and terminal weight of juvenile crucian carp in the Qihe River, inducing them to achieve supercompensatory growth.

[0014] 2) This invention can promote the development of muscle tissue in juvenile crucian carp in the Qihe River, increase the number of muscle fibers, and make muscle growth mainly manifested as muscle fiber hyperplasia, which is beneficial to improving the growth potential of fish and subsequent aquaculture performance.

[0015] 3) This invention induces rapid growth in juvenile crucian carp of the Qihe River while maintaining a relatively stable physiological state. After treatment using the method of this invention, the liver antioxidant capacity of juvenile crucian carp of the Qihe River is enhanced, and lipid peroxidation damage is not significantly aggravated, which helps to reduce the risk of oxidative stress that may occur during the starvation-refeeding process.

[0016] 4) This invention helps optimize the energy distribution and metabolic state of juvenile crucian carp in the Qihe River. After treatment using the method of this invention, the metabolic burden on the liver of juvenile crucian carp in the Qihe River is reduced, and the body can use more energy to restore the rapid growth process after feeding, thereby improving the growth efficiency of juvenile crucian carp in the Qihe River.

[0017] 5) The method of the present invention has a clear cycle and is easy to operate. It can achieve the growth promotion effect simply by adjusting the feeding rhythm. It does not require the use of additional exogenous growth promoters or complex special equipment, and is suitable for promotion and application in indoor tanks, recirculating aquaculture systems and large-scale aquaculture production.

[0018] 6) This invention sets up a 4-day complete starvation treatment within a 28-day breeding cycle, which can reduce the number of feeding days, which is conducive to reducing feed input, reducing uneaten feed and breeding waste discharge, and has good economic and ecological benefits.

[0019] 7) The growth-promoting effect of the method of this invention has a clear biological basis. Related results show that after treatment with the method of this invention, signaling pathways and key genes related to growth regulation, energy metabolism, and cellular stress adaptation in the muscle tissue of juvenile crucian carp in the Qihe River undergo responsive regulation, providing molecular mechanistic support for the method's induction of supercompensation growth. Attached Figure Description

[0020] Figure 1 The graph shows the effects of different starvation-refeeding rearing methods on the body length and weight of juvenile crucian carp in the Qihe River. S0 represents 28 days of continuous feeding; S2 represents 2 days of continuous starvation followed by 5 days of continuous feeding, repeated 4 times; S4 represents 4 days of continuous starvation followed by 24 days of continuous feeding, which is the method group of this invention; and S8 represents 8 days of continuous starvation followed by 20 days of continuous feeding.

[0021] Figure 2 Figure showing the effects of different starvation-refeeding rearing methods on the muscle tissue morphology and muscle fiber characteristics of juvenile crucian carp in the Qihe River.

[0022] Figure 3 The effects of different starvation-refeeding rearing methods on the muscle fiber characteristics of juvenile crucian carp in the Qihe River are shown in the figure. Among them, A is the statistical graph of the number of muscle fibers; B is the statistical graph of the maximum diameter of muscle fibers; and C is the statistical graph of the minimum diameter of muscle fibers.

[0023] Figure 4 Figure showing the effects of different starvation-refeeding rearing methods on the intestinal tissue morphology of juvenile crucian carp in the Qihe River.

[0024] Figure 5 The effect of different starvation-refeeding rearing methods on intestinal structural parameters of juvenile crucian carp in the Qihe River is shown in the figure. In the figure, A represents muscle layer thickness; B represents crypt depth; C represents villus height; and D represents villus width.

[0025] Figure 6 Figure showing the effects of different starvation-refeeding rearing methods on the liver tissue morphology of juvenile crucian carp in the Qihe River.

[0026] Figure 7 The effect of different starvation-refeeding rearing methods on the antioxidant capacity of the liver of juvenile crucian carp in the Qihe River is shown in the figure. Among them, A represents the change in superoxide dismutase (SOD) activity; B represents the change in catalase (CAT) activity; C represents the change in glutathione peroxidase (GSH-Px) activity; and D represents the change in malondialdehyde (MDA) content.

[0027] Figure 8 The effect of different starvation-refeeding rearing methods on the liver metabolic capacity of juvenile crucian carp in the Qihe River is shown in the figure. Among them, A represents the change in alanine aminotransferase (ALT) activity; B represents the change in alkaline phosphatase (AKP) activity; and C represents the change in lactate dehydrogenase (LDH) activity.

[0028] Figure 9 The effect of different starvation-refeeding rearing methods on the intestinal digestive capacity of juvenile crucian carp in the Qihe River is shown in the figure. Among them, A represents the change in lipase activity; B represents the change in amylase activity; and C represents the change in trypsin activity.

[0029] Figure 10 KEGG pathway enrichment analysis of differentially expressed genes in muscle tissue of juvenile crucian carp under different starvation-refeeding rearing methods is presented. In the diagrams, A represents the KEGG pathway enrichment analysis of differentially expressed genes in muscle tissue of groups S2 and S0; B represents the KEGG pathway enrichment analysis of differentially expressed genes in muscle tissue of groups S4 and S0; and C represents the KEGG pathway enrichment analysis of differentially expressed genes in muscle tissue of groups S8 and S0.

[0030] Figure 11 Real-time quantitative PCR results of key compensatory growth-related genes in the muscle tissue of juvenile crucian carp in the Qihe River under different starvation-refeeding rearing methods. Detailed Implementation

[0031] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments, but this should not be construed as limiting the invention. Unless otherwise specified, the technical means used in the following embodiments are conventional means well known to those skilled in the art, and the materials, reagents, etc. used in the following embodiments are commercially available unless otherwise specified.

[0032] Qihe River crucian carp starvation - refeeding method I. Experimental Methods (a) Preparation of the aquaculture system A 200 L circular indoor tank was used as the culture container. Before the experiment, the culture tank, aeration equipment, and related equipment were cleaned and disinfected, then rinsed with clean water and fresh water was added. During the experiment, the aeration device was turned on to maintain sufficient dissolved oxygen in the water, and uneaten food, feces, and other pollutants were removed in a timely manner according to the water quality to maintain a stable aquatic environment.

[0033] (II) Selection and Adaptation of Experimental Fish Two-month-old, healthy, active, and uniformly sized Qihe crucian carp with intact bodies, no obvious mechanical damage, normal feeding and swimming behavior were selected as experimental subjects. The experimental fish underwent acclimatization rearing before entering the formal experiment to allow them to adapt to the indoor culture environment and Tongwei fish extruded compound feed.

[0034] During the temporary holding and experimental period, the aquatic environmental conditions were controlled as follows: water temperature 21.85±0.13℃, dissolved oxygen 6.80±0.18 mg / L, and pH 7.22±0.10. During the temporary holding period, the fish were fed twice daily at 09:30 and 16:30, using Tongwei extruded compound feed.

[0035] (III) Experimental Grouping After the temporary rearing period, the juvenile crucian carp from the Qihe River were randomly divided into 4 groups, with 3 replicates in each group and 10 fish in each replicate. The treatment methods for each group are as follows: Group S0: Feeded continuously for 28 days, serving as the continuous feeding control group; Group S2: After being starved for 2 consecutive days, the animals were fed for 5 consecutive days, and this cycle was repeated 4 times. This group served as the control group. Group S4: After 4 days of continuous starvation, the animals were fed continuously for 24 days, which is the group described in this invention. Group S8: After being starved for 8 consecutive days, the animals were fed continuously for 20 days, serving as the control group.

[0036] The total rearing cycle for all groups was 28 days. Except for the different starvation-refeeding treatment methods, the water conditions, daily management methods, feeding methods, and feed types during the recovery feeding phase were consistent across all groups.

[0037] (iv) Processing of the method group of the present invention Group S4, as the method group of this invention, first undergoes a complete starvation treatment for 4 consecutive days after the start of the 28-day breeding cycle. During the complete starvation treatment, no feed or nutrients are provided, only normal breeding management is carried out, including oxygenation, water quality monitoring, water exchange or circulating filtration, and timely removal of feces and other contaminants.

[0038] After four consecutive days of complete starvation, a 24-day resumption of feeding phase will begin immediately. During this period, fish will be fed twice daily at 09:30 and 16:30, each time until they appear to be satiated. Apparent satiation is defined as a significant decrease in the fish's feeding activity, a marked slowdown in feed intake, or the appearance of small amounts of uneaten food in the water. Uneaten food should be removed promptly during the resumption of feeding to prevent it from rotting and affecting water quality.

[0039] (v) Sample collection After the aquaculture experiment, all groups of experimental fish were fasted for 24 hours. Following the fasting period, experimental fish were randomly selected from each treatment group for measurement and sampling. First, the body length and weight of the experimental fish were measured to evaluate the effects of different starvation-refeeding treatments on the growth performance of juvenile crucian carp in the Qihe River. Subsequently, muscle, liver, and intestinal tissues were collected. Muscle tissue was used for histological observation and transcriptome analysis; liver tissue was used for histological observation, antioxidant indices, and metabolic enzyme activity detection; and intestinal tissue was used for histological observation and digestive enzyme activity detection.

[0040] (vi) Indicator Testing (1) Growth index detection: The final body length and final weight of each group of Qihe crucian carp juveniles were measured, and the differences between different treatment groups were compared to determine the effect of different starvation-refeeding treatments on growth performance.

[0041] (2) Histological observation of muscle, intestine and liver: muscle, intestine and liver tissues were collected, fixed, embedded, sectioned and stained with HE, and the tissue morphology of muscle, intestine and liver was observed. The number of muscle fibers, the maximum diameter and the minimum diameter of muscle fibers were measured to evaluate the muscle growth pattern. The villus length, crypt depth, muscle layer thickness and villus width of the intestine were measured to evaluate the physiological state of the intestine. The position of cell nuclei and the morphology of hepatocytes in the liver were observed to evaluate the physiological state of the liver.

[0042] (3) Detection of liver antioxidant and metabolic enzyme indicators: liver tissue was collected and antioxidant-related indicators such as glutathione peroxidase and malondialdehyde, as well as metabolic enzyme activities such as alanine aminotransferase, were detected to evaluate the effects of different treatments on the antioxidant capacity and metabolic status of fish.

[0043] (6) Detection of intestinal digestive enzyme indicators: Intestinal tissue was collected and the activities of lipase, amylase and trypsin were detected to evaluate the effects of different treatments on digestive capacity and nutrient utilization status.

[0044] (7) Muscle transcriptome analysis and real-time quantitative PCR verification: Muscle tissue was collected for transcriptome sequencing analysis, differentially expressed genes were screened, and KEGG pathway enrichment analysis was performed to analyze the molecular basis of the supercompensation growth induced by the method of this invention in juvenile crucian carp of the Qihe River. At the same time, some differentially expressed genes were selected for real-time quantitative PCR verification to verify the reliability of the transcriptome sequencing results.

[0045] II. Data Processing and Statistical Analysis The data obtained during the above experiments, including body length, weight, number of muscle fibers, maximum and minimum diameter of muscle fibers, liver antioxidant indicators, liver metabolic enzyme activity, and intestinal digestive enzyme activity, were compiled and analyzed.

[0046] All data are expressed as mean ± standard deviation. Student's t-test was used for comparisons between two groups, and one-way ANOVA was used for comparisons among multiple groups. P < A value of 0.05 indicates a statistically significant difference. When significant differences exist between different treatment groups, different letters or asterisks are used for punctuation.

[0047] Muscle transcriptome data were used to screen differentially expressed genes under different starvation-refeeding treatments and to perform KEGG pathway enrichment analysis to analyze the molecular basis of the supercompensation growth induced in juvenile crucian carp by the method of this invention.

[0048] Real-time quantitative PCR was used to verify the reliability of transcriptome sequencing results. Relative gene expression levels were measured using a 2-1 ratio. -ΔΔCt Method calculation.

[0049] III. Experimental Results Experimental results showed that different starvation-refeeding treatments had varying effects on the growth performance of juvenile crucian carp in the Qihe River. Compared with the continuous feeding control group S0 and other starvation-refeeding treatment groups S2 and S8, group S4, i.e., the method group of this invention, had higher terminal body length and terminal body weight at the end of the 28-day rearing cycle, and the differences were statistically significant. This indicates that the single-cycle treatment of complete starvation for 4 consecutive days followed by continuous feeding for 24 days can effectively induce supercompensation growth in juvenile crucian carp in the Qihe River.

[0050] Histological results of the muscle tissue showed that the number of muscle fibers in the Qihe crucian carp juveniles in group S4 (method of the present invention) and the other starvation-refeeding treatment groups S2 and S8 increased, while the maximum and minimum diameters of the muscle fibers decreased. In particular, the number of muscle fibers in group S4 was significantly increased compared to group S0, indicating that the rapid growth induced by the method of the present invention is mainly related to muscle fiber proliferation. These results demonstrate that the method of the present invention can not only improve the growth level of fish but also promote muscle tissue development and enhance the subsequent growth potential of the fish.

[0051] Histological results of the intestines showed that different starvation-refeeding treatments had a certain impact on the intestinal morphology of juvenile crucian carp in the Qihe River. Compared with the S0 control group, although no significant difference was found, the S2 group had the lowest muscle layer thickness and a significantly increased villus height, indicating partial remodeling of the intestinal structure. The S4 group had a relatively high muscle layer thickness, a slightly increased crypt depth, and a villus height that was higher than the S0 group but lower than the S2 group. The S8 group had a muscle layer thickness and villus width between the S2 and S4 groups, and the lowest villus height (not reaching a significant difference). Comprehensive analysis showed that the S4 group, treated by the method of this invention, exhibited a relatively balanced state between intestinal structural remodeling and functional recovery, maintaining a high muscle layer thickness while accompanied by moderate villus growth, which is beneficial for subsequent nutrient digestion and absorption and growth recovery.

[0052] Histological results of the liver showed that group S4, treated with the method of the present invention, exhibited a certain degree of liver tissue structural response after starvation-refeeding treatment, mainly manifested as adjustments in hepatocyte morphology and tissue structure, suggesting adaptive changes in liver tissue during metabolic reprogramming. This change is a physiological response to the redistribution of energy metabolism under starvation-refeeding conditions, rather than obvious irreversible damage. Compared with group S4, the control group S0 showed intact liver tissue structure, regular hepatocyte arrangement, normal cell morphology, and no obvious abnormalities; groups S2 and S8 both showed varying degrees of liver tissue structural changes. In summary, group S4, treated with the method of the present invention, achieved supercompensated growth while maintaining liver tissue within an acceptable structural response range, indicating that the starvation-refeeding strategy has a good balance between promoting growth and maintaining physiological homeostasis.

[0053] Liver physiological and biochemical tests showed differences in glutathione peroxidase (GSH-Px) and malondialdehyde (MDA) levels among groups S0, S2, S4, and S8. Group S4 had the highest GSH-Px level, while group S0 had the lowest. MDA levels in group S4 did not show a significant increase, while group S2 had the highest MDA level among all experimental groups. The significantly increased GSH-Px level in juvenile crucian carp in group S4, while the significantly decreased MDA level, indicates that the method of this invention promotes rapid growth without causing significant lipid peroxidation damage, thus helping to maintain antioxidant homeostasis in the fish. Simultaneously, the decreased alanine aminotransferase (ALT) activity in the liver of group S4 suggests a relatively reduced burden of protein catabolism, which is beneficial for restoring energy allocation from the feeding stage to the growth process.

[0054] The results of intestinal digestive enzyme detection showed that lipase activity was high in group S2, while the overall digestive enzyme activity was relatively low in group S8. In contrast, the activities of various digestive enzymes in group S4 were at an intermediate regulatory level, with amylase and protease activities remaining within a relatively stable range, and lipase activity showing no significant abnormal fluctuations, indicating a relatively coordinated digestive function. Group S4 exhibited digestive enzyme activity regulation characteristics adapted to its supercompensatory growth during the recovery feeding phase, demonstrating that the method of this invention can influence the digestion and utilization of nutrients and provide a physiological basis for rapid growth after recovery feeding.

[0055] Muscle transcriptomics and real-time quantitative PCR results further demonstrate that the method of this invention can regulate the FoxO signaling pathway and sgk1, irs1b The expression of genes related to compensatory growth provides molecular mechanistic support for its induction of supercompensatory growth.

[0056] IV. Experimental Conclusions Different starvation-refeeding treatments had varying effects on the compensatory growth of juvenile crucian carp in the Qihe River. Compared with the continuous feeding control group S0 and other starvation-refeeding treatment groups S2 and S8, group S4 (the method group of this invention) showed superior performance in terms of terminal body length, terminal body weight, muscle fiber hyperplasia, liver antioxidant status, and muscle transcriptome response. These results indicate that a single-cycle treatment of 4 consecutive days of complete starvation followed by 24 consecutive days of refeeding can effectively induce supercompensatory growth in juvenile crucian carp in the Qihe River and maintain a relatively stable physiological state.

[0057] It should be noted that the conditions such as water temperature, dissolved oxygen, pH, feeding time, stocking density and stocking container in the above implementation method can be routinely adjusted according to the actual aquaculture production conditions, but the core technical solution of "4 consecutive days of complete starvation + 24 consecutive days of resumption of feeding + only once within 28 days" should not be changed.

[0058] The foregoing has shown and described the basic principles, main features and advantages of the present invention. Various changes and modifications can be made to the present invention without departing from the spirit and scope thereof, and all such changes and modifications fall within the scope of the present invention as claimed.

Claims

1. A single-cycle starvation-refeeding culture method for inducing supercompensatory growth in juvenile crucian carp of the Qihe River, characterized in that... The specific steps are as follows: Step S1, Selection and temporary rearing of juvenile crucian carp from the Qi River: 1) Select healthy, intact Qihe crucian carp of uniform size, with normal feeding and swimming behavior, as the breeding target; 2) Place the juvenile crucian carp in the aquaculture system for acclimatization. During the acclimatization period, keep the water temperature, dissolved oxygen and pH stable, and feed them with Tongwei fish extruded compound feed twice a day. After the fish’s feeding and swimming status stabilizes, they will enter the formal aquaculture cycle. Step S2, complete starvation treatment: After the formal breeding cycle begins, the juvenile crucian carp of Qihe River are subjected to complete starvation for 4 consecutive days. During the complete starvation period, no feed or nutrients are provided, and only normal water quality management is carried out. Step S3, resume feeding process: After four consecutive days of complete starvation, the juvenile crucian carp of Qihe River were fed again for 24 consecutive days. During the feeding period, they were fed with Tongwei fish extruded compound feed twice a day until they appeared to be satiated. The process consists of four consecutive days of complete starvation and 24 consecutive days of refeeding, forming a complete single-cycle starvation-refeeding culture process. The total culture cycle is 28 days, and the starvation-refeeding culture process is only performed once within this culture cycle. This is used to significantly increase the final body length and final weight of Qihe crucian carp juveniles and induce them to achieve supercompensation growth.

2. The single-cycle starvation-refeeding culture method for inducing supercompensatory growth in juvenile crucian carp of the Qihe River according to claim 1, characterized in that: The Qihe crucian carp mentioned in step S1 are 2-month-old Qihe crucian carp.

3. The single-cycle starvation-refeeding culture method for inducing supercompensatory growth in juvenile crucian carp of the Qihe River according to claim 1, characterized in that: In step S1, the adaptive temporary rearing conditions are controlled with a water temperature of 20-24℃, dissolved oxygen of not less than 5.5mg / L, and pH of 7.0-7.5; the rearing system is one of an indoor tank, a recirculating aquaculture system, or a pond cage.

4. The single-cycle starvation-refeeding culture method for inducing supercompensatory growth in juvenile crucian carp of the Qihe River according to claim 1, characterized in that: During the adaptive temporary rearing period described in step S1, uneaten food and feces are regularly removed, and the water body is kept in a state of sufficient dissolved oxygen and water circulation.

5. The single-cycle starvation-refeeding culture method for inducing supercompensatory growth in juvenile crucian carp of the Qihe River according to claim 1, characterized in that: During the adaptive rearing period described in step S1 and the resumption of feeding period described in step S4, feeding was carried out in accordance with the conventional feeding method, and the feed used was Tongwei fish extruded compound feed.

6. The single-cycle starvation-refeeding culture method for inducing supercompensatory growth in juvenile crucian carp of the Qihe River according to claim 1, characterized in that: Normal water quality management during the complete starvation treatment described in step S2 includes oxygenation, water quality monitoring, circulating filtration, water exchange, and removal of feces and other pollutants to maintain the stability of the aquatic environment.

7. The single-cycle starvation-refeeding culture method for inducing supercompensatory growth in juvenile crucian carp of the Qihe River according to claim 1, characterized in that: The apparent satiety mentioned in step S3 refers to stopping feeding when the fish’s feeding activity decreases significantly, the feed intake rate slows down significantly, or a small amount of uneaten feed appears in the water.

8. The single-cycle starvation-refeeding culture method for inducing supercompensatory growth in juvenile crucian carp of the Qihe River according to claim 1, characterized in that: The starvation-refeeding method is used to promote the development of muscle tissue in juvenile crucian carp in the Qihe River, increase the number of muscle fibers, and make muscle growth mainly manifested as muscle fiber hyperplasia, which is beneficial to improving the growth potential of fish and subsequent aquaculture performance.

9. The single-cycle starvation-refeeding culture method for inducing supercompensatory growth in juvenile crucian carp of the Qihe River according to claim 1, characterized in that: The starvation-refeeding method is used to enhance the liver antioxidant capacity of juvenile crucian carp in the Qihe River, prevent significant aggravation of lipid peroxidation damage, and maintain a relatively stable physiological state of juvenile crucian carp in the Qihe River.

10. The single-cycle starvation-refeeding culture method for inducing supercompensatory growth in juvenile crucian carp of the Qihe River according to claim 1, characterized in that: The starvation-refeeding method helps reduce the metabolic burden on the liver, allowing the body to use more energy to recover from the rapid growth process after feeding, thereby improving the growth efficiency of Qihe crucian carp juveniles.

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