Macrobrachium rosenbergii parent strengthening feed based on sex difference regulation

Abstract

The invention discloses a macrobrachium rosenbergii parent strengthening feed based on sex difference regulation and control, and relates to the technical field of aquaculture. The feed comprises special fortified materials for the female shrimps and the male shrimps, the addition level of n-3 LC-PUFA is regulated and controlled by the fortified materials for the female shrimps and the male shrimps, and different nutritional requirements of gonad development of the female shrimps and the male shrimps are accurately matched. The feed breaks through the formula limitation of'one-step cutting of female and male 'of the traditional feed, effectively promotes the development of the ovary of the female prawn and the testis of the male prawn, improves the gonad maturity, solves the industrial problems that the gonad development of the male and female parent prawns is asynchronous and the reproductive window period is staggered, greatly improves the overall reproductive performance of the macrobrachium rosenbergii parent, and improves the economic benefit of the macrobrachium rosenbergii. Key technical support is provided for large-scale and high-quality cultivation of parents, and the application prospect is good.

Description

Technical Field

[0001] This invention relates to the field of aquaculture technology, and in particular to a fortified feed for giant freshwater prawn broodstock based on sex difference regulation. Background Technology

[0002] The giant freshwater prawn (Macrobrachium rosenbergii) is an important freshwater economic shrimp species globally, but its aquaculture industry has long been constrained by problems such as germplasm degradation and asynchronous gonadal development in broodstock, severely impacting reproductive efficiency and high-quality industry development. Inadequate nutritional supply during the broodstock rearing stage is the core cause of these problems. In particular, the lack of sex-specific gonadal-stimulating feed formulations is a key factor leading to asynchronous male and female development in giant freshwater prawn broodstock, directly limiting the improvement of broodstock reproductive performance.

[0003] In the field of crustacean aquaculture, there are existing technologies related to feeds that promote the maturation of aquatic animal gonads. For example, patent CN1739377A discloses a feed additive that promotes the maturation of the gonads of Penaeus monodon. This technology promotes the maturation of the gonads of Penaeus monodon broodstock by adding liquid highly unsaturated fatty acids to the feed, along with astaxanthin, cholesterol, vitamins and other components. Although it can improve the maturity and egg production of Penaeus monodon broodstock to a certain extent, this technology itself has obvious technical defects, and its formula design is completely targeted at the physiological characteristics of Penaeus monodon, so it cannot be directly applied to the breeding of Macrobrachium rosenbergii broodstock. On the one hand, the excessively high proportion of liquid highly unsaturated fatty acids added in this technology leads to an extremely high risk of lipid oxidation in the feed, which not only reduces the storage stability and palatability of the feed but also increases the metabolic burden on the hepatopancreas of shrimp. On the other hand, there are fundamental differences between tiger prawns and giant freshwater prawns in terms of gonadal development mechanisms and nutritional requirements. The nutritional ratio of this technology cannot be adapted to the gonadal development needs of giant freshwater prawn broodstock. Blindly applying it will not only fail to achieve the effect of promoting gonadal development but may also cause problems such as abnormal growth and development of broodstock shrimp.

[0004] The current challenge in breeding giant freshwater prawns lies in the lack of sex-specific gonadal-stimulating feed formulations, which is also the key reason for the asynchronous development of male and female prawns. In traditional giant freshwater prawn farming methods, farmers struggle to precisely control the proportions of various nutrients in the feed, and are unable to provide targeted nutritional support based on the different physiological needs and developmental stages of male and female prawns, ultimately hindering the effective improvement of prawn reproductive performance.

[0005] The current "one-size-fits-all" approach to nutrition supply for both male and female prawns exacerbates the problem of low reproductive performance in broodstock giant freshwater prawns. On the one hand, if the content or ratio of n-3 LC-PUFA in the feed is insufficient, it cannot meet the core nutritional needs for ovarian development in female prawns. This directly leads to delayed ovarian development, low maturity, a significant reduction in egg production, and even the appearance of "empty shells" with extremely poor egg quality. Even if mating is completed, it is difficult to guarantee the survival rate of the larvae. On the other hand, if farmers blindly increase the overall fat level of the feed to meet the lipid requirements for ovarian development in female prawns, it will cause excessive metabolic burden on the hepatopancreas of male prawns, significantly reducing sperm motility. This makes it more likely that male prawns will enter the reproductive decline stage before the female prawns have completed ovarian maturity, resulting in a severe misalignment of the reproductive window between male and female broodstocks, making effective mating impossible, and ultimately leading to a significant reduction in the egg-carrying rate and fertilization rate of broodstocks. Summary of the Invention

[0006] The purpose of this invention is to provide a sex-dependent broodstock-enhanced feed for giant freshwater prawns to address the problems existing in the prior art.

[0007] To achieve the above objectives, the present invention provides the following solution: One of the technical solutions of this invention is to provide a gonad-enhancing feed for female giant freshwater prawns, comprising the following components by weight percentage: 25-30% chicken meal, 6-8% prawn shell powder, 4-6% intestinal membrane powder, 2-3% chicken liver powder, 6-8% soybean meal, 7-8% fermented soybean meal, 5-6% cottonseed meal, 3-5% yeast powder, 21% high-gluten flour, 0-5% soybean oil, 1-5% fish oil, 1-1.5% phospholipid oil, 0.3-0.4% lysine, 0.1-0.2% methionine, 0.2-0.5% red phage yeast, 0.01-0.02% vitamin C phosphate, 1-1.5% calcium dihydrogen phosphate, 0.5-1.0% zeolite powder, 1-1.5% premix, 0.2-0.3% choline chloride, and 0.8-1.0% sea salt.

[0008] The second technical solution of this invention provides a gonad-enhancing feed for male giant freshwater prawns, comprising the following components by weight percentage: 25-30% chicken meal, 2-3% prawn shell powder, 4-6% intestinal membrane powder, 2-3% chicken liver powder, 9-10% soybean meal, 10-12% fermented soybean meal, 5-6% cottonseed meal, 3-5% yeast powder, 22% high-gluten flour, 0-4% soybean oil, 1-1.5% phospholipid oil, 0.8-4% fish oil, 1-1.5% calcium dihydrogen phosphate, 1-2% zeolite powder, 1-1.5% premix, 0.2-0.3% choline chloride, and 0.8-1.0% sea salt.

[0009] In this invention, fish oil is used to provide n-3 LC-PUFA; the content of n-3 LC-PUFA is 0.4-2.0% based on the total mass of the gonadal development-enhancing feed for female giant freshwater prawns; and the content of n-3 LC-PUFA is 0.36-1.31% based on the total mass of the gonadal development-enhancing feed for male giant freshwater prawns.

[0010] More preferably, the fish oil contains 15-18% EPA, 20-25% DHA, and the mass ratio of DHA to EPA is 1.0-1.2.

[0011] Furthermore, the premix is ​​a premix specifically for giant freshwater prawn farming, containing vitamins and minerals required for the growth and development of giant freshwater prawns, and meeting the micronutrient requirements of broodstock prawns during gonadal development.

[0012] The feed of this invention can be prepared using conventional pelleting processes for aquatic feeds. After the components are mixed evenly in proportion, they are crushed, conditioned, pelleted, and dried to obtain pelleted feed with a particle size suitable for feeding broodstock giant freshwater prawns. The moisture content of the pelleted feed is controlled below 10%, which facilitates storage and feeding.

[0013] The third technical solution of the present invention is to provide the application of the above-mentioned enhanced gonadal development feed for female giant freshwater prawns and / or enhanced gonadal development feed for male giant freshwater prawns in the breeding of gonadal development of giant freshwater prawns.

[0014] The fourth technical solution of the present invention provides a method for regulating the sex difference in gonadal development of giant freshwater prawn parents through nutrition. The method involves feeding female giant freshwater prawns with the aforementioned enhanced gonadal development feed and feeding male giant freshwater prawns with the same enhanced gonadal development feed, with the feeding of male prawns starting later than that of female prawns.

[0015] Furthermore, female giant freshwater prawns were continuously fed the aforementioned gonad-enhancing feed for 50-60 days, while male giant freshwater prawns were continuously fed the same gonad-enhancing feed for 40-50 days, starting 10 days later than the females.

[0016] Furthermore, both female and male shrimp were fed three times a day.

[0017] Furthermore, the amount of feed given at one time is 1.5-2% of the total body weight of the corresponding giant freshwater prawn.

[0018] The present invention discloses the following technical effects: This invention has achieved significant technical results by developing a special gonad-enhancing feed for male and female giant freshwater prawns, which enables precise nutritional regulation based on sex differences.

[0019] This invention provides a feed with differentiated n-3 LC-PUFA supplementation levels based on the physiological differences in gonadal development between male and female broodstock shrimp. This effectively adapts to the different nutritional needs of male and female broodstock shrimp, significantly promoting the normal development of the female ovaries and the male testes, and improving gonadal maturity and reproductive cell quality. Simultaneously, this invention successfully solves the industry problem of asynchronous gonadal development in male and female broodstock shrimp in traditional aquaculture, effectively avoiding the problem of misaligned reproductive windows and significantly improving the synchronization rate of gonadal development between male and female broodstock shrimp.

[0020] This invention breaks through the limitations of traditional feed formulations that use a "one-size-fits-all" approach, providing core technical support for the large-scale, high-quality breeding of giant freshwater prawn broodstock, and is of great significance to promoting the development of the giant freshwater prawn aquaculture industry. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 The effect of n-3 LC-PUFA levels in the feed on the gonadal index (ovarian index) of giant freshwater prawns in an embodiment of the present invention; Figure 2 The effect of n-3 LC-PUFA content in the feed on the histology of the ovary of Giant River Prawn (40X) in this embodiment of the invention; A represents the CK group, and BF represent the n-3 LC-PUFA addition groups of 0.4%, 0.8%, 1.2%, 1.6%, and 2.0%, respectively; Figure 3 The effect of n-3 LC-PUFA content in the feed on the histology of the testes of giant freshwater prawns (20X) in this embodiment of the invention; A is the CK group, and BF represent the experimental groups with n-3 LC-PUFA levels of 0.36%, 0.6%, 0.83%, 1.1% and 1.31%, respectively. Detailed Implementation

[0023] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0024] It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the invention. Furthermore, with respect to numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Any stated value or intermediate value within a stated range, as well as each smaller range between any other stated value or intermediate value within said range, is also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0025] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. All references to this specification are incorporated by way of citation to disclose and describe methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail.

[0026] Various modifications and variations can be made to the specific embodiments described in this specification without departing from the scope or spirit of the invention, as will be apparent to those skilled in the art. Other embodiments derived from this specification will also be readily apparent to those skilled in the art. This specification and embodiments are merely exemplary.

[0027] The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.

[0028] It should be noted that any aspects not described in detail in this invention are conventional practices in the field and are not the focus of this invention.

[0029] All raw materials used in all embodiments are aquatic feed grade raw materials. Among them, n-3 LC-PUFA is provided by fish oil, which has an EPA percentage of 15-18%, a DHA percentage of 20-25%, and a DHA to EPA mass ratio of 1.0-1.2. The premix is ​​a premix specifically for giant freshwater prawn farming, containing vitamins A, D, E, and K, minerals such as calcium, phosphorus, iron, zinc, and selenium, as well as complex amino acids required for the gonadal development of giant freshwater prawns.

[0030] All feeds in the embodiments were prepared using conventional aquatic feed pelleting processes. After crushing, mixing, conditioning, pelleting, and drying, sinking pellets with a particle size of 3-5 mm were obtained. The moisture content of the pelleted feed was controlled at 8-10%, which facilitates storage and feeding.

[0031] Example 1 This embodiment provides a sex-differential broodstock enhanced feed for giant freshwater prawns, including a sex-differential broodstock enhanced feed for female giant freshwater prawns and a sex-differential broodstock enhanced feed for male giant freshwater prawns. The feed for enhancing the gonadal development of female giant freshwater prawns contains 1% fish oil, corresponding to a n-3 LC-PUFA content of 0.4%; the feed for enhancing the gonadal development of male giant freshwater prawns contains 0.8% fish oil, corresponding to a n-3 LC-PUFA content of 0.36%. The specific formulation is as follows: By weight percentage, the gonadal development enhancement feed for female giant freshwater prawns consists of the following components: Chicken meal 30%, shrimp shell powder 6%, intestinal membrane powder 6%, chicken liver powder 3%, soybean meal 6%, fermented soybean meal 7%, cottonseed meal 6%, yeast powder 3%, high-gluten flour 21%, soybean oil 4%, fish oil 1%, phospholipid oil 1.5%, lysine 0.4%, methionine 0.2%, red phloem yeast 0.2%, vitamin C phosphate 0.02%, calcium dihydrogen phosphate 1.5%, zeolite powder 0.68%, premix 1.5%, choline chloride 0.2%, sea salt 0.8%.

[0032] By weight percentage, the gonadal development enhancement feed for male giant freshwater prawn broodstock consists of the following components: Chicken meal 30%, shrimp shell powder 3%, intestinal membrane powder 5%, chicken liver powder 2%, soybean meal 9%, fermented soybean meal 10%, cottonseed meal 6%, yeast powder 3%, high gluten flour 22%, soybean oil 3.2%, phospholipid oil 1%, fish oil 0.8%, calcium dihydrogen phosphate 1.5%, zeolite powder 1%, premix 1.5%, choline chloride 0.2%, sea crystal 0.8%.

[0033] Example 2 This embodiment provides a sex-differential broodstock enhanced feed for giant freshwater prawns, including a sex-differential broodstock enhanced feed for female giant freshwater prawns and a sex-differential broodstock enhanced feed for male giant freshwater prawns. The feed for enhancing the gonadal development of female giant freshwater prawns contains 2% fish oil, corresponding to a n-3 LC-PUFA content of 0.8%; the feed for enhancing the gonadal development of male giant freshwater prawns contains 1.6% fish oil, corresponding to a n-3 LC-PUFA content of 0.6%. The specific formulation is as follows: By weight percentage, the gonadal development enhancement feed for female giant freshwater prawns consists of the following components: Chicken meal 30%, shrimp shell powder 6%, intestinal membrane powder 6%, chicken liver powder 3%, soybean meal 6%, fermented soybean meal 7%, cottonseed meal 6%, yeast powder 3%, high-gluten flour 21%, soybean oil 3%, fish oil 2%, phospholipid oil 1.5%, lysine 0.4%, methionine 0.2%, red phloem yeast 0.2%, vitamin C phosphate 0.02%, calcium dihydrogen phosphate 1.5%, zeolite powder 0.68%, premix 1.5%, choline chloride 0.2%, sea salt 0.8%.

[0034] By weight percentage, the gonadal development enhancement feed for male giant freshwater prawn broodstock consists of the following components: Chicken meal 30%, shrimp shell powder 3%, intestinal membrane powder 5%, chicken liver powder 2%, soybean meal 9%, fermented soybean meal 10%, cottonseed meal 6%, yeast powder 3%, high gluten flour 22%, soybean oil 2.4%, phospholipid oil 1%, fish oil 1.6%, calcium dihydrogen phosphate 1.5%, zeolite powder 1%, premix 1.5%, choline chloride 0.2%, sea crystal 0.8%.

[0035] Example 3 This embodiment provides a sex-differential broodstock enhanced feed for giant freshwater prawns, including a sex-differential broodstock enhanced feed for female giant freshwater prawns and a sex-differential broodstock enhanced feed for male giant freshwater prawns. The feed for enhancing the gonadal development of female giant freshwater prawns contains 3% fish oil, corresponding to a n-3 LC-PUFA content of 1.2%; the feed for enhancing the gonadal development of male giant freshwater prawns contains 2.4% fish oil, corresponding to a n-3 LC-PUFA content of 0.83%. The specific formulation is as follows: By weight percentage, the gonadal development enhancement feed for female giant freshwater prawns consists of the following components: Chicken meal 30%, shrimp shell powder 6%, intestinal membrane powder 6%, chicken liver powder 3%, soybean meal 6%, fermented soybean meal 7%, cottonseed meal 6%, yeast powder 3%, high-gluten flour 21%, soybean oil 2%, fish oil 3%, phospholipid oil 1.5%, lysine 0.4%, methionine 0.2%, red phloem yeast 0.2%, vitamin C phosphate 0.02%, calcium dihydrogen phosphate 1.5%, zeolite powder 0.68%, premix 1.5%, choline chloride 0.2%, sea salt 0.8%.

[0036] By weight percentage, the gonadal development enhancement feed for male giant freshwater prawn broodstock consists of the following components: Chicken meal 30%, shrimp shell powder 3%, intestinal membrane powder 5%, chicken liver powder 2%, soybean meal 9%, fermented soybean meal 10%, cottonseed meal 6%, yeast powder 3%, high gluten flour 22%, soybean oil 1.6%, phospholipid oil 1%, fish oil 2.4%, calcium dihydrogen phosphate 1.5%, zeolite powder 1%, premix 1.5%, choline chloride 0.2%, sea crystal 0.8%.

[0037] Example 4 This embodiment provides a sex-differential broodstock enhanced feed for giant freshwater prawns, including a sex-differential broodstock enhanced feed for female giant freshwater prawns and a sex-differential broodstock enhanced feed for male giant freshwater prawns. The feed for enhancing the gonadal development of female giant freshwater prawns contains 4% fish oil, corresponding to a n-3 LC-PUFA content of 1.6%; the feed for enhancing the gonadal development of male giant freshwater prawns contains 3.2% fish oil, corresponding to a n-3 LC-PUFA content of 1.1%. The specific formulation is as follows: By weight percentage, the gonadal development enhancement feed for female giant freshwater prawns consists of the following components: Chicken meal 30%, shrimp shell powder 6%, intestinal membrane powder 6%, chicken liver powder 3%, soybean meal 6%, fermented soybean meal 7%, cottonseed meal 6%, yeast powder 3%, high-gluten flour 21%, soybean oil 1%, fish oil 4%, phospholipid oil 1.5%, lysine 0.4%, methionine 0.2%, red phloem yeast 0.2%, vitamin C phosphate 0.02%, calcium dihydrogen phosphate 1.5%, zeolite powder 0.68%, premix 1.5%, choline chloride 0.2%, sea salt 0.8%.

[0038] By weight percentage, the gonadal development enhancement feed for male giant freshwater prawn broodstock consists of the following components: Chicken meal 30%, shrimp shell powder 3%, intestinal membrane powder 5%, chicken liver powder 2%, soybean meal 9%, fermented soybean meal 10%, cottonseed meal 6%, yeast powder 3%, high gluten flour 22%, soybean oil 0.8%, phospholipid oil 1%, fish oil 3.2%, calcium dihydrogen phosphate 1.5%, zeolite powder 1%, premix 1.5%, choline chloride 0.2%, sea crystal 0.8%.

[0039] Example 5 This embodiment provides a sex-differential broodstock enhanced feed for giant freshwater prawns, including a sex-differential broodstock enhanced feed for female giant freshwater prawns and a sex-differential broodstock enhanced feed for male giant freshwater prawns. The feed for enhancing the gonadal development of female giant freshwater prawns contains 5% fish oil, corresponding to an n-3 LC-PUFA content of 2.0%; the feed for enhancing the gonadal development of male giant freshwater prawns contains 4.0% fish oil, corresponding to an n-3 LC-PUFA content of 1.31%. The specific formulation is as follows: By weight percentage, the gonadal development enhancement feed for female giant freshwater prawns consists of the following components: Chicken meal 30%, shrimp shell powder 6%, intestinal membrane powder 6%, chicken liver powder 3%, soybean meal 6%, fermented soybean meal 7%, cottonseed meal 6%, yeast powder 3%, high-gluten flour 21%, fish oil 5%, phospholipid oil 1.5%, lysine 0.4%, methionine 0.2%, red phloem yeast 0.2%, vitamin C phosphate 0.02%, calcium dihydrogen phosphate 1.5%, zeolite powder 0.68%, premix 1.5%, choline chloride 0.2%, sea salt 0.8%.

[0040] By weight percentage, the gonadal development enhancement feed for male giant freshwater prawn broodstock consists of the following components: Chicken meal 30%, shrimp shell powder 3%, intestinal membrane powder 5%, chicken liver powder 2%, soybean meal 9%, fermented soybean meal 10%, cottonseed meal 6%, yeast powder 3%, high gluten flour 22%, phospholipid oil 1%, fish oil 4%, calcium dihydrogen phosphate 1.5%, zeolite powder 1%, premix 1.5%, choline chloride 0.2%, sea crystal 0.8%.

[0041] Verification of breeding effects: The feeds from the above five examples were used in a gonadal development and rearing experiment of broodstock giant freshwater prawns. A blank control group (CK group) was also set up. Throughout the experiment, separate pond rearing and differentiated feeding for males and females were adopted. The rearing environment and feeding conditions of all experimental groups and control groups were kept consistent. The specific operation is as follows: Parent stock selection and separation: Healthy Macrobrachium rosenbergii with intact appendages and no disease or injury were selected as reserve parent stock. The initial body weight of females was 16.61±0.38g, and that of males was 17.49±0.14g. After sexing, the males and females were separated into two separate rearing ponds, one on each side of a rearing pond equipped with a polyethylene partition. The partition was perforated (1-1.5cm in diameter) to ensure water circulation. Equal amounts of netting were placed in the rearing ponds for hiding. Females were placed in the larger rearing area, and males in the smaller rearing area. A total of 78 Macrobrachium rosenbergii were stocked, with a female-to-male ratio of 2:1. The blank control group consisted of Macrobrachium rosenbergii parent stock of the same size and health condition, placed in rearing ponds of the same size with the same female-to-male ratio and separation method. All parent stock were temporarily reared for 7 days to acclimatize to the rearing environment. Feeding Procedures: Female shrimp in each experimental group were continuously fed their corresponding female-specific fortified feed for 56 days, while male shrimp were fed their corresponding male-specific fortified feed for 42 days, 10 days later than the females. The control group was fed conventional broodstock feed for giant freshwater prawns. The feeding time and cycle for both male and female broodstock were completely consistent with the experimental groups. All groups were fed three times daily at 7:00, 16:00, and 22:00. Each feeding amount was 1.5-2% of the total body weight of the shrimp in the corresponding rearing area. The feeding amount was adjusted flexibly according to the shrimp's real-time feeding behavior to ensure no uneaten feed and sufficient intake by the broodstock. Aquaculture environment control: The aquaculture environment parameters in the rearing ponds of the experimental group and the blank control group were kept consistent. The water temperature in the rearing ponds was stably controlled at 26-28℃, the dissolved oxygen content was greater than 6.5 mg / L, and the pH value of the water was maintained at 7.3-7.8. One-third of the water was removed and replaced daily at 8:00 AM. The netting was cleaned once a week. Ammonia nitrogen and nitrite nitrogen in the water were tested daily to ensure that ammonia nitrogen < 0.2 mg / L and nitrite nitrogen < 0.02 mg / L. The effect of n-3 LC-PUFA levels in the feed on the gonadal index (ovarian index) of giant freshwater prawns is described in [reference needed]. Figure 1 .

[0042] The effect of n-3 LC-PUFA content in feed on the histological characteristics of giant freshwater prawn ovaries (40X) is shown in [reference needed]. Figure 2 In the figure, A represents the CK group, and B to F represent the n-3 LC-PUFA addition groups with 0.4%, 0.8%, 1.2%, 1.6%, and 2.0% respectively; OG: oogonia; Oo: oocytes; PVS: interoocyte space; Y: yolk granules; PVS: interoocyte space.

[0043] from Figure 2 As can be seen, the CK group was filled with a large number of oogonia, with a small number of mature oocytes and relatively large intercellular spaces. Adding n-3 LC-PUFA significantly improved the development of the ovary in *Macrobrachium rosenbergii*. Specifically, the 0.8%-1.2% addition group showed more mature oocytes, with tightly packed oocytes and smaller intercellular spaces; the 1.2% addition group showed more pronounced accumulation of yolk granules. These results indicate that adding 0.8%-1.2% n-3 LC-PUFA to the diet can promote ovarian development in *Macrobrachium rosenbergii*.

[0044] Figure 3 Effect of n-3 LC-PUFA content in feed on the histology of testes in giant freshwater prawns (20X); A represents the control group, and BF represent the experimental groups with n-3 LC-PUFA levels of 0.36%, 0.6%, 0.83%, 1.1%, and 1.31%, respectively; Sg: spermatogonia; Psc: primary spermatocytes; Sc: spermatocytes; Ss: secondary spermatocytes; S: sperm.

[0045] from Figure 3 The results showed that the CK group was dominated by primary spermatocytes, with only a small number of secondary spermatocytes and sperm; the 0.36% group had loosely arranged seminiferous tubules with some sperm production; the 0.6% group had tightly arranged seminiferous tubules with the highest proportion of mature sperm; the 0.83% group was similar to the 0.6% group, with a small number of immature cells remaining; the 0.83% and 1.1% groups had a higher proportion of immature cells, but their overall development was better than the control group. Histological results of the testes indicated that the 0.36-0.6% groups of *Macrobrachium rosenbergii* had a higher proportion of mature sperm in their testes, indicating better testicular development.

[0046] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A feed for enhancing the gonadal development of female giant freshwater prawn parents, characterized in that, By weight percentage, it consists of the following components: 25-30% chicken meal, 6-8% shrimp shell meal, 4-6% intestinal membrane meal, 2-3% chicken liver meal, 6-8% soybean meal, 7-8% fermented soybean meal, 5-6% cottonseed meal, 3-5% yeast powder, 21% high-gluten flour, 0-5% soybean oil, 1-5% fish oil, 1-1.5% phospholipid oil, 0.3-0.4% lysine, 0.1-0.2% methionine, 0.2-0.5% red phage yeast, 0.01-0.02% vitamin C phosphate, 1-1.5% calcium dihydrogen phosphate, 0.5-1.0% zeolite powder, 1-1.5% premix, 0.2-0.3% choline chloride, and 0.8-1.0% sea salt.

2. A feed for enhancing the gonadal development of male giant freshwater prawn parents, characterized in that, By weight percentage, it consists of the following components: 25-30% chicken meal, 2-3% shrimp shell meal, 4-6% intestinal membrane meal, 2-3% chicken liver meal, 9-10% soybean meal, 10-12% fermented soybean meal, 5-6% cottonseed meal, 3-5% yeast powder, 22% high-gluten flour, 0-4% soybean oil, 1-1.5% phospholipid oil, 0.8-4% fish oil, 1-1.5% calcium dihydrogen phosphate, 1-2% zeolite powder, 1-1.5% premix, 0.2-0.3% choline chloride, and 0.8-1.0% sea salt.

3. The application of the enhanced gonadal development feed for female giant freshwater prawns as described in claim 1 and / or the enhanced gonadal development feed for male giant freshwater prawns as described in claim 2 in the breeding of gonadal development of giant freshwater prawns.

4. A method for nutritional regulation of sex differences in gonadal development in parent giant freshwater prawns, characterized in that, Female giant freshwater prawns were fed with the gonadal development-enhancing feed for female giant freshwater prawns as described in claim 1, and male giant freshwater prawns were fed with the gonadal development-enhancing feed for male giant freshwater prawns as described in claim 2, with the feeding of male prawns starting later than that of female prawns.

5. The method for regulating sex differences in gonadal development in Giant freshwater prawn parents according to claim 4, characterized in that, Female giant freshwater prawns were fed the aforementioned gonad-enhancing feed for 50-60 days, while male giant freshwater prawns were fed the same feed for 40-50 days, starting 10 days later than the females.

6. The method for regulating sex differences in gonadal development in Giant freshwater prawn parents according to claim 5, characterized in that, Both female and male shrimp should be fed three times a day.

7. The method for regulating sex differences in gonadal development in Giant freshwater prawn parents according to claim 6, characterized in that, The amount of feed given at one time is 1.5-2% of the total body weight of the corresponding giant freshwater prawn.

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