Application of tenebrio molitor larvae in crayfish breeding

Abstract

The invention discloses crayfish bait containing tenebrio molitor larvae and application of the tenebrio molitor larvae in crayfish breeding. The tenebrio molitor larvae serve as effective ingredients in the crayfish bait. Wherein the weight percentage content of tenebrio molitor larvae in the crayfish bait is 10%-30%. According to the method, the crayfish is used as a research object, the influence of the tenebrio molitor larvae replacing part of feed on crayfish breeding is researched, the crayfish bred through the method has positive influences on the growth performance and the oxidation resistance, and the breeding economic benefits of the crayfish are increased.

Description

Technical Field

[0001] The invention relates to the technical field of aquaculture, and in particular to application of yellow mealworm larvae in crayfish breeding. Technical Background

[0002] Tenebrio molitor belongs to the order Coleoptera, the family Tenebrioidae, also known as mealworm, mealworm genus, and is distributed worldwide. The larvae of Tenebrio molitor are rich in nutritional value, with a crude protein content of about 47%-71% in dry matter, and contain a variety of trace elements such as phosphorus, potassium, iron, sodium, aluminum, 16 kinds of amino acids necessary for animal growth, and high levels of unsaturated fatty acids, especially linoleic acid and α-linolenic acid.

[0003] In recent years, my country's crayfish farming industry has maintained a good development momentum. Crayfish are typical omnivorous aquatic animals that like to feed on natural plant and animal baits such as aquatic plants and insects. With the popularity of crayfish on people's tables, it is necessary to provide bait that can better improve the yield and quality of crayfish. Summary of the invention

[0004] The present invention first provides a crayfish bait, which contains yellow mealworm larvae;

[0005] The weight percentage content of yellow mealworm larvae in the crayfish bait is 10%-30%; the preferred weight percentage content is 20%;

[0006] The present invention also provides an application of yellow mealworm larvae in crayfish breeding, specifically, the yellow mealworm larvae are used as an effective ingredient in crayfish bait;

[0007] The weight percentage content of yellow mealworm larvae in the crayfish bait is 10%-30%, and the preferred weight percentage content is 20%.

[0008] As an effective ingredient in crayfish bait, mealworm larvae can improve the growth performance of crayfish, including terminal body weight, weight gain rate, specific growth rate and meat yield; they can also enhance the antioxidant capacity of crayfish, including the activity of superoxide dismutase, catalase and glutathione peroxidase.

[0009] The present invention also provides a management method for crayfish farming, which comprises the following steps:

[0010] Crayfish should be fed with mealworm larvae, and the water temperature should be maintained at 20-25℃, pH value should be maintained at 7.5-8.4, dissolved oxygen should be maintained at 6.0-7.0mg / L, NH 4 + -N 0.042-0.053mg / L, NO 2-N 0.031-0.039mg / L, COD12.0-14.7mg / L;

[0011] The weight percentage content of yellow mealworm larvae in the crayfish bait is 10%-30%, and the preferred weight percentage content is 20%.

[0012] Compared with the prior art, the present invention has the following advantages and effects:

[0013] (1) The presence of mealworm larvae in crayfish bait can significantly improve the growth performance of crayfish in aquaculture, and increase its yield and meat yield;

[0014] (2) Crayfish feed contains mealworm larvae, which can significantly enhance the antioxidant capacity of crayfish in culture, including the activities of superoxide dismutase, catalase and glutathione peroxidase.

[0015] At the same time, mealworm larvae, as natural bait, can also provide a reasonable combination of animal and plant protein for the growth of crayfish, as well as other nutrients that commercial feeds do not have, which is beneficial to enhancing the growth performance and antioxidant capacity of crayfish, thereby increasing yield and breeding efficiency. DETAILED DESCRIPTION

[0016] The following examples are only used to further illustrate the content of the present invention, but should not be construed as limiting the present invention. Without departing from the spirit and essence of the present invention, modifications or substitutions made to the method, steps or conditions of the present invention all belong to the scope of the present invention. The experimental methods and reagents without specifying the specific conditions in the examples are all in accordance with the conventional conditions in the art.

[0017] The crayfish pellet feed used below was purchased from Hubei Zhaoliang Biotechnology Co., Ltd.

[0018] The mealworm larvae and crayfish used below were from the Zhuangxing Comprehensive Experimental Station of Shanghai Academy of Agricultural Sciences.

[0019] The mealworm larvae were cultured to the 6th instar, with an average weight of 0.12±0.02 mg. The crayfish (Procambarus clarkii) were all in good condition without broken limbs, with an average weight of 9.1±0.15 g.

[0020] Embodiment 1:

[0021] (1) Experimental design

[0022] 450 crayfish were randomly distributed in 15 concrete pools (1.0m×1.0m×0.4m) for recirculating water culture, and the bottom of each pool was sheltered by a sufficient number of PVC pipes and crayfish nests. The 15 culture pools were divided into 5 experimental groups (A, B, C, D and E), each of which included 3 replicates.

[0023] The experimental group A was fed with 100% pellet feed and served as a control. The experimental groups B, C, D and E were fed with mealworm larvae instead of pellet feed at a weight ratio of 5%, 10%, 20% and 30% respectively. The crayfish were fed at 17:00 every day, during which the circulating water circulation was temporarily stopped. During the feeding process, the amount of food equivalent to 4%-5% of body weight was provided, and the same amount of food was provided in each pool, and the remaining food was salvaged half an hour after the feeding was completed.

[0024] The experiment was conducted at the Zhuangxing Comprehensive Experimental Station of the Shanghai Academy of Agricultural Sciences for 10 weeks. The photoperiod was maintained at 14L:10D, and the number of crayfish deaths was accurately counted daily. The water quality in the pond was regularly assessed five times a day using a portable water quality analyzer, including water temperature, pH, and dissolved oxygen (DO), and a chemical method was used to quantify NH 4 + -N,NO 2 The aquaculture water temperature is maintained at 20-25℃, pH value is maintained at 7.5-8.4, dissolved oxygen is maintained at 6.0-7.0mg / L, NH 4 + -N 0.042-0.053mg / L, NO 2 -N 0.031-0.039mg / L, COD 12.0-14.7mg / L.

[0025] The experimental data were calculated and analyzed using Microsoft Excel and SPSS22.0 software. One-way analysis of variance (ANOVA) was used to evaluate the significant differences between the experimental groups, followed by Tukey's test. The experimental data are expressed as standard deviation ± mean, and p < 0.05 indicates statistical significance.

[0026] (2) Determination of crayfish growth performance

[0027] After 10 weeks, all crayfish were anesthetized on ice after fasting for 24 hours. The number and weight of crayfish in each pool were counted. They were then dissected and the muscles and hepatopancreas were accurately weighed.

[0028] The growth performance index in this experiment was calculated using the following formula:

[0029] Survival rate (%) = 100 × final number of crayfish / initial number of crayfish;

[0030] Weight gain rate (%) = 100 × (final weight - initial weight) / initial weight;

[0031] Specific growth rate (% / d) = 100 × (ln final body weight - ln initial body weight) / 70d;

[0032] Hepatosomatic index (%) = 100 × hepatopancreas weight / final body weight;

[0033] Meat yield (%) = 100 × muscle weight / final body weight.

[0034] Table 1 Effects of different ratios of mealworm larvae replacing feed on the growth performance of crayfish

[0035] A B C D E Initial body weight (g) 9.08±0.14 9.10±0.16 9.04±0.14 9.11±0.15 9.12±0.11 Final body weight (g) <![CDATA[37.13±3.42 b ]]> <![CDATA[39.17±2.66 ab ]]> <![CDATA[40.81±3.18 ab ]]> <![CDATA[41.90±2.77 a ]]> <![CDATA[42.03±3.17 a ]]> Survival rate (%) 83.33±3.33 85.56±5.09 91.11±1.92 90.00±3.33 87.78±1.92 Weight gain rate (%) <![CDATA[308.93±37.72 b ]]> <![CDATA[330.44±29.20 ab ]]> <![CDATA[351.46±35.20 ab ]]> <![CDATA[359.91±30.35 a ]]> <![CDATA[360.86±34.79 a ]]> Specific growth rate (% / d) <![CDATA[2.01±0.13 b ]]> <![CDATA[2.08±0.10 ab ]]> <![CDATA[2.15±0.11 a ]]> <![CDATA[2.18±0.09 a ]]> <![CDATA[2.18±0.11 a ]]> Hepatocellular index (%) <![CDATA[6.68±0.69 b ]]> <![CDATA[6.83±0.54 ab ]]> <![CDATA[7.11±0.45 ab ]]> <![CDATA[7.48±0.43 a ]]> <![CDATA[7.32±0.51 ab ]]> Meat yield (%) <![CDATA[17.88±0.64 b ]]> <![CDATA[19.81±0.89 a ]]> <![CDATA[20.95±1.36 a ]]> <![CDATA[21.50±1.36 a ]]> <![CDATA[20.92±1.36 a ]]>

[0036] The test results are shown in Table 1. Replacing the feed at a ratio of 10%-30% can effectively increase the final body weight, weight gain rate, specific growth rate and meat yield of crayfish (p < 0.05).

[0037] (3) Determination of antioxidant capacity of crayfish

[0038] Three crayfish were randomly selected from each culture pond, and the hepatopancreas was collected and stored at −80°C for subsequent detection of antioxidant enzyme activities.

[0039] The hepatopancreas was rinsed with ice-cold phosphate buffer and then cut into small pieces. Freshly prepared ice-cold physiological saline was used to prepare tissue homogenate at a ratio of 1:10. The homogenate was centrifuged at 4000 rpm for 10 minutes at 4°C, and the supernatant was collected and saved for measurement. The activity of antioxidants (superoxide dismutase, catalase, and glutathione peroxidase) was determined using an enzyme activity kit (purchased from Nanjing Jiancheng Bioengineering Research Institute Co., Ltd.).

[0040] Table 2 Effects of different ratios of mealworm larvae replacing feed on the antioxidant capacity of crayfish

[0041]

[0042] The test results are shown in Table 2. In the activities of superoxide dismutase, catalase and glutathione peroxidase, group D showed significant increases compared with the control group (p < 0.05), and also performed better than other tests. Combined with the impact on growth performance and breeding costs, replacing pellet feed with 20% of mealworm larvae can significantly improve the economic benefits of breeding.

Claims

1. A crayfish bait, characterized in that It contains mealworm larvae.

2. The crayfish bait according to claim 1, wherein the weight percentage content of yellow mealworm larvae is 10-30%.

3. The crayfish bait according to claim 2, wherein the weight percentage content of yellow mealworm larvae is 20%.

4. The application of mealworm larvae in crayfish farming, using mealworm larvae as an effective ingredient in crayfish bait; The weight percentage content of yellow mealworm larvae in the crayfish bait is 10%-30%.

5. The use according to claim 4, wherein the weight percentage content of yellow mealworm larvae in the crayfish bait is 20%.

6. A management method for crayfish farming, characterized in that The method comprises the following steps: Crayfish were fed with mealworm larvae, and the water temperature was maintained at 20-25℃, pH value was maintained at 7.5-8.4, dissolved oxygen was maintained at 6.0-7.0mg / L, NH4 + -N 0.042-0.053mg / L, NO2-N 0.031-0.039mg / L, COD 12.0-14.7mg / L; The weight percentage content of yellow mealworm larvae in the crayfish bait is 10%-30%.

7. The management method for crayfish farming according to claim 6, wherein the weight percentage content of yellow mealworm larvae in the crayfish bait is 20%.

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