Method for controlling body color of tilapia

Abstract

The application discloses a method for regulating the color of tilapia, comprising the following steps: S1, juvenile stage: daily white light LED lamp for the first time irradiation, daily feeding 2-3 times of basic feed; S2, juvenile stage: daily white light LED lamp for the second time irradiation, daily 1-2 times of yellow light LED lamp irradiation when the second time irradiation is performed, daily feeding 3-4 times of basic feed mixed with mixed material for feeding; S3, adult stage: daily yellow light LED lamp for the third time irradiation, daily 1-2 times of blue light LED lamp irradiation when the third time irradiation is performed, daily feeding 3-4 times of basic feed. By regulating the development of the growth stage of the juvenile stage, the juvenile stage and the adult stage of the tilapia, selecting the appropriate light conditions, matching the growth phototaxis conditions of the tilapia, feeding the basic feed mixed with different component mixed materials in each stage, the pigment deposition in the fish body is rapidly guided, and the color of the fish body becomes more bright.

Description

Technical Field

[0001] This invention relates to the field of aquaculture technology, and in particular to a method for controlling the body color of tilapia. Background Technology

[0002] Tilapia are a common and economically important aquatic fish, characterized by early maturity, multiple spawning cycles per year, rapid reproduction, wide adaptability, and the ability to incubate fry in their mouths. Fish body color is produced by pigments in the fish selectively absorbing specific wavelengths of light while reflecting other wavelengths. Environmental conditions influence pigment formation, and fish adapt to their environment through changes in body color. The quality and market value of a fish are closely related to its body color and markings.

[0003] The life cycle of tilapia is roughly divided into three stages: a juvenile stage (1-2 months), a larval stage (3-5 months), and an adult stage (6-10 months). Tilapia are mostly blackish-gray in color, with a dull appearance. In aquatic environments, their color can easily turn whitish. Insufficient dissolved oxygen in the water causes the gills and body color to become pale; rapid and short-term changes in water temperature can cause the color to lighten; high ammonia levels can deepen the red color of the gills and cause the body to become pale; and drug stress can also cause color changes. Environmental and nutritional factors influence the color of the fish, resulting in a inconsistent or blackish appearance, leading to lower market value and economic worth. There is limited research on the biological basis of tilapia body color formation during aquaculture, especially on gray-black-white tilapia. For the development and widespread application of tilapia, effectively improving and enhancing fish body color has long been an important goal of aquatic germplasm selection. This paper proposes methods for regulating tilapia body color, and studying the mechanisms of body color variation and differentiation in fish is of great significance for improving fish quality. Summary of the Invention

[0004] In view of this, the present invention provides a method for regulating the body color of tilapia, which has the characteristics of regulating the body color of fish at various growth stages, enhancing pigment deposition, promoting the growth quality of fish, and regulating water quality balance.

[0005] The technical means adopted in this invention are as follows: A method for regulating the body color of tilapia, comprising the following steps:

[0006] S1. Fry stage: Place tilapia fry in a culture pond with a temperature of 25-30℃ and equipped with light sources of different colors. Provide white LED lights for 8-10 hours of illumination daily for the first time, with a light intensity of 1500-1800 lux. Feed them with basic feed 2-3 times a day, with a daily feed amount of 2-3% of the fry's weight.

[0007] S2. Juvenile stage: Provide 12-15 hours of white LED light for the second irradiation daily, with a light intensity of 1000-1200 lux. During the second irradiation, provide yellow LED light irradiation 1-2 times daily. Feed the basal feed 3-4 times daily, and add 5-10% of the weight of the mixed feed to the basal feed. The daily feed amount is 4-5% of the juvenile fish's weight. The mixed feed includes: degummed kelp powder, galactomannan, monosodium glutamate, soybean lecithin, and lactic acid bacteria.

[0008] S3, Adult stage: Provide yellow LED light for 16-18 hours daily for the third irradiation, with a light intensity of 800-1000 lux. During the third irradiation, provide blue LED light irradiation 1-2 times daily. Feed the fish 3-4 times daily with basic feed, and add 12-15% of the weight of mixed feed to the basic feed. The daily feed amount is 6-7% of the adult fish's weight.

[0009] Furthermore, the basic feed comprises the following raw materials in parts by weight: 15-25 parts fish meal, 15-18 parts mosquito and fly larvae, 15-18 parts marigold petal powder, 8-12 parts calendula petal powder, 3-5 parts alfalfa, 8-10 parts chlorella powder, 10-15 parts wheat bran, 5-8 parts cassava flour, 1-3 parts fish oil, 1-2 parts palm oil, 1-2 parts calcium dihydrogen phosphate, and 1-3 parts compound premix.

[0010] Furthermore, the basic feed comprises the following ingredients in parts by weight: 20 parts fish meal, 15 parts mosquito and fly larvae, 16 parts marigold petal powder, 10 parts calendula petal powder, 3 parts alfalfa, 10 parts chlorella powder, 12 parts wheat bran, 6 parts cassava flour, 3 parts fish oil, 2 parts palm oil, 1 part calcium dihydrogen phosphate, and 2 parts compound premix.

[0011] Furthermore, the mixture comprises the following raw materials in parts by weight: 20-25 parts degummed kelp powder, 30-35 parts galactomannan, 15-20 parts monosodium glutamate, 15-20 parts soybean lecithin, and 10-15 parts lactic acid bacteria.

[0012] Furthermore, the mixture comprises the following raw materials in parts by weight: 22 parts degummed kelp powder, 32 parts galactomannan, 18 parts monosodium glutamate, 16 parts soybean lecithin, and 12 parts lactic acid bacteria.

[0013] Furthermore, during the juvenile and adult stages, a low concentration of hydrogen peroxide solution (1.0–3.0 mg / L) and photosynthetic bacteria are added every 15–22 days to regulate the water quality.

[0014] Furthermore, the effective viable count of photosynthetic bacteria is 10 × 10⁻⁶. 8 ~12×10 8 CFU / mL.

[0015] Furthermore, after vacuuming the waste every 4 to 6 days, change 30 to 50% of the water.

[0016] The beneficial effects of this invention are as follows: By using the tilapia body color regulation method provided by this invention, the development of tilapia during the juvenile, young, and adult stages, the phototaxis of each stage, and the selection of appropriate light intensity with a gradient decreasing trend, and by intermittently introducing yellow and blue light during the light irradiation period, the growth and development of tilapia are matched, the body color of tilapia during growth and development is improved, making its body color more vibrant, and improving high-density growth and aquaculture. At each stage, a basic feed mixed with a blend of ingredients was provided. Tilapia tend to feed on plant-based food, which quickly guides pigment deposition in their bodies, making their colors more vibrant. The blended feed promotes absorption, resulting in a brighter color. Furthermore, the feed contains no artificial chemical colorants, reducing the problems associated with hormones. By controlling lighting conditions and using the basic feed mixed with color-enhancing ingredients, the fish's colors become translucent. This basic feed not only makes the fish's color more vibrant but also provides various nutrients to improve the fish's surface color, ensuring that the farmed tilapia's color is neither too pale nor too black, but rather somewhere in between, and with a more vibrant hue. Water quality was also adjusted through water changes. This water treatment is harmless to tilapia, reduces nitrite concentration, inhibits harmful Vibrio bacteria, and effectively improves the survival rate of the farmed tilapia. Detailed Implementation

[0017] The principles and features of the present invention are described below. The embodiments given are only for explaining the present invention and are not intended to limit the scope of the present invention.

[0018] Example 1

[0019] A method for controlling the body color of tilapia includes the following steps:

[0020] S1. Fry Stage: Tilapia fry are placed in a rearing pond at 25℃ equipped with light sources of different colors. The stocking density is 8000-10000 fry / acre. The first irradiation is provided daily with 8 hours of white LED light at an intensity of 1500 lux. Basic feed is given twice daily, at a rate of 2% of the fry's weight. Every 4 days, 30% of the water is changed after sludge removal. The basic feed consists of the following ingredients by weight: 18 parts fishmeal, 15 parts mosquito larvae, 15 parts marigold petal powder, 8 parts calendula petal powder, 3 parts alfalfa, 8 parts chlorella powder, 10 parts wheat bran, 5 parts cassava flour, 1 part fish oil, 1 part palm oil, 1 part calcium dihydrogen phosphate, and 1 part compound premix.

[0021] S2, Juvenile Stage: Provide 12 hours of white LED light daily for the second irradiation, with a light intensity of 1000 lux. During this second irradiation, provide yellow LED light irradiation once daily. Feed three times daily with a basic diet, adding 5% of the mixed feed by weight. The daily feed amount is 4% of the juvenile fish's weight. Every 15 days, add a low concentration of hydrogen peroxide solution (1.0 mg / L) and photosynthetic bacteria to adjust the water quality. The effective viable count of photosynthetic bacteria should be 10 × 10⁻⁶. 8 CFU / mL. Change 30% of the water after vacuuming every 4 days. The mixture consists of the following ingredients by weight: 20 parts degummed kelp powder, 30 parts galactomannan, 15 parts monosodium glutamate, 15 parts soybean lecithin, and 10 parts lactic acid bacteria.

[0022] S3, Adult Stage: Provide 16 hours of yellow LED light daily for the third irradiation, with a light intensity of 800 lux. During this third irradiation, provide blue LED light once daily. Feed three times daily with basic feed, adding 12% (by weight) of mixed feed to the basic feed. The daily feed amount is 6% of the adult fish's weight. Every 15 days, add a low concentration of hydrogen peroxide solution (1.0 mg / L) and photosynthetic bacteria to adjust the water quality. The effective viable count of photosynthetic bacteria should be 10 × 10⁻⁶. 8 CFU / mL. Replace 30% of the water every 4 days after vacuuming out the waste.

[0023] Example 2

[0024] A method for controlling the body color of tilapia includes the following steps:

[0025] S1. Fry Stage: Tilapia fry are placed in a rearing pond at 30℃ equipped with light sources of different colors. The stocking density is 8,000-10,000 fry / acre. The first irradiation is provided daily for 10 hours by white LED lights at an intensity of 1800 lux. Basic feed is given three times daily, with a daily feed amount of 3% of the fry's weight. Every six days, 50% of the water is changed after sludge removal. The basic feed consists of the following ingredients by weight: 25 parts fishmeal, 18 parts mosquito larvae, 18 parts marigold petal powder, 12 parts calendula petal powder, 5 parts alfalfa, 10 parts chlorella powder, 15 parts wheat bran, 8 parts cassava flour, 3 parts fish oil, 2 parts palm oil, 2 parts calcium dihydrogen phosphate, and 3 parts compound premix.

[0026] S2, Juvenile Stage: Provide 15 hours of white LED light daily for the second irradiation, with a light intensity of 1200 lux. During this second irradiation, provide yellow LED light twice daily. Feed four times daily with a basic diet, adding 10% of the mixed feed by weight. The daily feed amount is 5% of the juvenile fish's weight. Every 22 days, add a low concentration of 3.0 mg / L hydrogen peroxide solution and photosynthetic bacteria to adjust the water quality. The effective viable count of photosynthetic bacteria should be 12 × 10⁻⁶. 8 CFU / mL. Change 50% of the water after vacuuming every 6 days. The mixture consists of the following ingredients by weight: 25 parts degummed kelp powder, 35 parts galactomannan, 20 parts monosodium glutamate, 20 parts soybean lecithin, and 15 parts lactic acid bacteria.

[0027] S3, Adult Stage: Provide 18 hours of yellow LED light daily for the third irradiation, with a light intensity of 800-1000 lux. During this third irradiation, provide blue LED light twice daily. Feed four times daily with a basic feed, adding 15% of the mixed feed by weight. The daily feed amount is 7% of the adult fish's weight. Every 22 days, add a low concentration of 3.0 mg / L hydrogen peroxide solution and photosynthetic bacteria to adjust the water quality. The effective viable count of photosynthetic bacteria should be 12 × 10⁻⁶. 8 CFU / mL. Replace 50% of the water after vacuuming every 6 days.

[0028] Example 3

[0029] A method for controlling the body color of tilapia includes the following steps:

[0030] S1. Fry Stage: Tilapia fry are placed in a rearing pond at 26℃ equipped with light sources of different colors. The stocking density is 8000-10000 fry / acre. The first irradiation is provided daily with 9 hours of white LED light at an intensity of 1800 lux. Basic feed is given twice daily, at a rate of 2% of the fry's weight. Every 5 days, 40% of the water is changed after sludge removal. The basic feed consists of the following ingredients by weight: 20 parts fishmeal, 15 parts mosquito larvae, 16 parts marigold petal powder, 10 parts calendula petal powder, 3 parts alfalfa, 10 parts chlorella powder, 12 parts wheat bran, 6 parts cassava flour, 3 parts fish oil, 2 parts palm oil, 1 part calcium dihydrogen phosphate, and 2 parts compound premix.

[0031] S2, Juvenile Stage: Provide 14 hours of white LED light daily for the second irradiation, with a light intensity of 1200 lux. During this second irradiation, provide yellow LED light twice daily. Feed three times daily with a basic diet, adding 8% (by weight) of a mixed feed to the basic diet. The daily feed amount is 4% of the juvenile fish's weight. Every 18 days, add a low concentration of hydrogen peroxide solution (2.0 mg / L) and photosynthetic bacteria to adjust the water quality. The effective viable count of photosynthetic bacteria should be 12 × 10⁻⁶. 8 CFU / mL. Change 40% of the water after vacuuming every 5 days. The mixture consists of the following raw materials in parts by weight: 22 parts degummed kelp powder, 32 parts galactomannan, 18 parts monosodium glutamate, 16 parts soybean lecithin, and 12 parts lactic acid bacteria.

[0032] S3, Adult Stage: Provide 17 hours of yellow LED light daily for the third irradiation, with a light intensity of 1000 lux. During this third irradiation, provide blue LED light twice daily. Feed three times daily with basic feed, adding 14% (by weight) of mixed feed to the basic feed. The daily feed amount is 6% of the adult fish's weight. Every 20 days, add a low concentration of hydrogen peroxide solution (2.0 mg / L) and photosynthetic bacteria to adjust the water quality. The effective viable count of photosynthetic bacteria should be 12 × 10⁻⁶. 8 CFU / mL. Replace 40% of the water every 5 days after vacuuming out the waste.

[0033] In the mosquito and fly larvae in Examples 1 to 3 above, in addition to being rich in nutrients such as protein, fat, polysaccharide, and minerals, they also contain bioactive substances such as chitin, antimicrobial peptides, lectins, and lysozyme.

[0034] Marigold petal powder: dried and ground into powder, it contains approximately 232 mg / kg of carotenoids, which can enhance the immunity of fish and improve their digestive function.

[0035] Calendula petal powder: contains 8000mg / kg of lutein.

[0036] Milk clover: It is rich in carotene, has good palatability, and can maintain the nitrogen cycle in aquaculture ponds, thereby improving feed utilization.

[0037] Chlorella powder: contains 4475mg / kg of carotenoids and various nutrients.

[0038] Degummed kelp powder: It contains rich nutrients, which can replenish the minerals and vitamins in the water, improve the skin color of fish, enhance the brightness of their colors, and increase the feed consumption rate.

[0039] Galactomannan: The mannan oligosaccharides produced by its decomposition can be absorbed by beneficial bacteria in the fish, improving the composition of the gut microbiota, reducing bacterial infection, promoting the digestion and absorption of energy, protein, and cellulose, and improving meat quality.

[0040] Monosodium glutamate (MSG): It greatly promotes growth, development, and immunity. Together with galactomannan, it promotes the reproduction of beneficial bacteria in fish and improves feed utilization.

[0041] Soy lecithin: The activity of lipase in fish is not as high as that of amylase. Soy lecithin can enhance the digestive function of lipase, improve the utilization rate of fat, and enhance disease resistance.

[0042] Lactic acid bacteria: These are beneficial bacteria that enable the basic feed in the intestines to produce a variety of enzymes, promote the balance of vitamins and proteins, and enhance disease resistance. At the same time, lactic acid bacteria can regulate the algae and bacteria balance in water quality by decomposing residual feed and other algal organic matter.

[0043] Effect test

[0044] Comparative Example 1

[0045] The difference between this comparative example and Example 3 is that the light intensity of the first, second, and third irradiations was 1000 lux.

[0046] Comparative Example 2

[0047] The difference between this comparative example and Example 3 is that the white LED lamp provides 12 hours of illumination per day for the first, second, and third irradiations.

[0048] Comparative Example 3

[0049] The difference between this comparative example and Example 3 is that the juvenile, young, and adult fish were fed only basic feed 2 to 3 times a day, with a daily feed amount of 4% of the weight of the young fish.

[0050] Comparative Example 4

[0051] The difference between this comparative example and Example 3 is as follows: S3, Adult stage: White LED lights provide 14 hours of illumination daily for the third irradiation, with a light intensity of 1200 lux. During the third irradiation, yellow LED lights are used twice daily. Basic feed is given three times daily, with 8% (by weight) of mixed feed added to the basic feed. The daily feed amount is 4% of the juvenile fish's weight. Every 18 days, a low concentration of hydrogen peroxide solution (2.0 mg / L) and photosynthetic bacteria are added to adjust the water quality. The effective viable count of photosynthetic bacteria is 12 × 10⁻⁶. 8 CFU / mL. Change 50% of the water after vacuuming every 13 days. The mixture consists of the following raw materials in parts by weight: 22 parts degummed kelp powder, 32 parts galactomannan, 18 parts monosodium glutamate, 16 parts soybean lecithin, and 12 parts lactic acid bacteria.

[0052] Comparative Example 5

[0053] The difference between this comparative example and Example 3 is that the mixture for the juvenile and adult stages includes the following raw materials in the following weight ratios: 15 parts degummed kelp powder, 25 parts galactomannan, 12 parts monosodium glutamate, 15 parts soybean lecithin, and 10 parts lactic acid bacteria.

[0054] Five tilapia of approximately 6 months age from Examples 1-3 and Comparative Examples 1-5, and five wild tilapia of the same weight (blank group) were selected for colorimetric value tests, tyrosinase activity tests, condition factor tests, and nutrient composition determination tests. Colorimetric value test: After anesthetizing the fish, removing surface mucus, and drying them, the fish were fixed on a CR-400 colorimeter to measure the brightness (L) of the area between the area below the dorsal fin and above the lateral line in each group of tilapia. ＊ Value. Tyrosinase activity test: The tyrosinase activity on the dorsal surface of the fish was measured using a tyrosinase (TYR) enzyme-linked immunosorbent assay (ELISA) kit on an enzyme-linked immunosorbent assay (ELISA) analyzer. The assay method was a one-step sandwich ELISA test with double antibodies. Condition percentage / % = average weight of experimental fish / body length of fish 3 ×100. Crude protein was determined using the Kjeldahl method (GB / T6432-2018), and crude fat content was determined using the Soxhlet extraction method (GBT6433-2006). The average results of each group of experiments are recorded in Table 1 below:

[0055]

[0056] The results showed that fish body color is a manifestation of the deposition of multiple pigments. Compared with the control method, the body color control method in this embodiment has better brightness, more vibrant appearance, and lower melanin production. Compared with the wild blackish-gray tilapia, the tilapia in this embodiment have a lighter body color, and are not whitish. Their body color depends on the control method of this invention. Because the water in the tilapia breeding pond is shallow and clear, its ability to absorb and scatter light is poor. The phototaxis of tilapia gradually weakens from the late juvenile stage to adulthood. Through staged controlled feeding, based on the characteristics of each growth stage, different colors, intensities, and durations of light are used to effectively control the fish body color, preventing slow growth, reducing tyrosinase activity, and minimizing melanin deposition. Combined with different feeds at each stage, the basic feed mixed with enhanced feed contains rich carotenoids, lutein, and other pigments, which have a good effect on the formation of fish body color. They also regulated the water quality to make the dark gray tilapia lighter in color and brighter in luster, while also improving the quality of the flesh.

[0057] In summary, the present invention provides a method for regulating the body color of tilapia. By controlling the development of tilapia during their juvenile, young, and adult stages, and selecting suitable lighting conditions with a gradient decreasing light intensity, and intermittently introducing yellow and blue light during the light exposure period, the method matches the phototactic conditions of tilapia growth. Furthermore, by feeding a basic feed containing different components at each stage, the method rapidly guides pigment deposition in the fish, resulting in more vibrant colors, improving high-density aquaculture, and reducing safety issues associated with hormones.

[0058] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for regulating the body color of tilapia, characterized in that, Comprise the following steps: S1, juvenile stage: the tilapia fry is placed in a breeding pond with a temperature of 25-30 DEG C and different color light source equipment, the first irradiation is provided by the white light LED lamp for 8-10h per day, the light intensity is 1500-1800 lux, the basic feed is fed 2-3 times per day, and the daily feeding amount is 2-3% of the weight of the juvenile fish; S2, juvenile stage: the second irradiation is provided by the white light LED lamp for 12-15h per day, the light intensity is 1000-1200 lux, the yellow light LED lamp irradiation is carried out 1-2 times per day during the second irradiation, the basic feed is fed 3-4 times per day, and the mixed material of 5-10% by weight is added to the basic feed for feeding, and the daily feeding amount is 4-5% of the weight of the juvenile fish, the mixed material comprises: degummed seaweed powder, galactomannan, sodium glutamate, soybean lecithin, lactic acid bacteria; S3, adult stage: the third irradiation is provided by the yellow light LED lamp for 16-18h per day, the light intensity is 800-1000 lux, the blue light LED lamp irradiation is carried out 1-2 times per day during the third irradiation, the basic feed is fed 3-4 times per day, and the mixed material of 12-15% by weight is added to the basic feed for feeding, and the daily feeding amount is 6-7% of the weight of the adult fish; The basic feed comprises the following raw materials in parts by weight: fish meal 15-25 parts, mosquito larvae 15-18 parts, marigold petal powder 15-18 parts, calendula petal powder 8-12 parts, Chinese milk vetch 3-5 parts, chlorella powder 8-10 parts, wheat bran 10-15 parts, cassava powder 5-8 parts, fish oil 1-3 parts, palm oil 1-2 parts, calcium dihydrogen phosphate 1-2 parts, and compound premix 1-3 parts; The mixed material comprises the following raw materials in parts by weight: degummed seaweed powder 20-25 parts, galactomannan 30-35 parts, sodium glutamate 15-20 parts, soybean lecithin 15-20 parts, and lactic acid bacteria 10-15 parts.

2. The method according to claim 1, wherein the fish is a tilapia. The basic feed comprises the following raw materials in parts by weight: fish meal 20 parts, mosquito larvae 15 parts, marigold petal powder 16 parts, calendula petal powder 10 parts, Chinese milk vetch 3 parts, chlorella powder 10 parts, wheat bran 12 parts, cassava powder 6 parts, fish oil 3 parts, palm oil 2 parts, calcium dihydrogen phosphate 1 part, and compound premix 2 parts.

3. The method of claim 1, wherein the fish is Tilapia. The mixed material comprises the following raw materials in parts by weight: degummed seaweed powder 22 parts, galactomannan 32 parts, sodium glutamate 18 parts, soybean lecithin 16 parts, and lactic acid bacteria 12 parts.

4. The method of claim 1, wherein the fish is Tilapia. The low-concentration hydrogen peroxide solution and photosynthetic bacteria are added to the water every 15-22 days during the juvenile stage and the adult stage.

5. The method according to claim 4, wherein the fish is a tilapia. The effective viable cell number of the photosynthetic bacteria is 10 x 10 8 12 x 10 8 CFU / mL.

6. The method of claim 1, wherein the fish is a tilapia. The water is changed by 30-50% after absorbing the dirt every 4-6 days.

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