CN116138354A - A kind of nutrient enhancer and application of larva opening feed - Google Patents

Abstract

The invention belongs to the field of aquatic feeds, and in particular relates to a nutrition enhancer of an opening feed for young fish and application thereof, wherein the nutrition enhancer comprises the following components: eicosapentaenoic acid, docosahexaenoic acid, eicosatetraenoic acid, complex enzyme preparation, vitamin C, lecithin, taurine and lysine. Aiming at the characteristics of small individual, weak activity capability, poor adaptability to external environment and undergrowth of digestive system of the young fish, the invention provides a nutrition enhancer capable of promoting ingestion of the young fish and obviously improving the growth and survival rate of the young fish and application thereof.

Description

A kind of nutrition enhancer and application of larva opening feed

technical field

The invention belongs to the field of aquatic feed, and in particular relates to a nutritional enhancer for larvae and juvenile fish feed and its application.

Background technique

Aquaculture seed is the most active and important production factor in aquaculture industry. As a special stage in the life history of fish, the larvae and juvenile stages of fry are quite different from juvenile and adult fish in their external morphology, internal structure and physiological metabolism. The larvae still have a yolk sac after hatching, and they receive endogenous nutrition first. As they grow and develop, the yolk sac disappears before entering the stage of exogenous nutrition. Affects the growth and health of larvae.

So far, in the production of cultured fish nursery, the opening of larvae and juveniles mainly relies on biological feed, including artemia, rotifers, and water worms. However, with the development of production, the biological feed used in traditional seedling production has greatly limited the production of seedlings due to its high production cost, unstable yield quality, and possible pathogenic microorganisms. Therefore, since the 1980s, people have begun to research and develop artificial compound feeds suitable for the feeding and digestion of aquatic seedlings, in order to partially or completely replace biological feeds. So far, some encouraging research results have been obtained, and commercial production has been carried out.

However, larvae and juveniles are small, have weak mobility, poor ability to adapt to the external environment, underdeveloped digestive system, insufficient or lack of secretion of digestive enzymes, and the nutritional composition that needs to be provided is very different from juvenile and adult fish, resulting in artificial cooperation in the opening stage The research and development of feed is full of difficulties. During the nursery stage of most farmed fish, the artificial compound feed at the opening stage is not precisely designed according to the nutritional needs and digestion and absorption characteristics of the seedling stage, resulting in indigestion and weakened stress resistance of the seedlings, which not only affects the survival rate, but even affect the subsequent development stage. Therefore, although the development of seedling pellet feed has made remarkable achievements, biological feed is still the first choice for the cultivation of aquaculture animal larvae, which is not conducive to large-scale and controllable farming.

Feed additive is one of the important raw materials used in the modern feed industry. Although it is used in a small amount in the feed, it has a significant effect on balancing or strengthening the nutrition of the feed, improving the quality of the feed, and improving the quality of animal products. In actual production, one or more animal health products, such as vitamin premix, Microecological preparations, etc., its role is to supplement the lack of nutrition, and can also improve the health level of larvae and juveniles during the feeding period.

However, how to increase the direct intake of artificial compound feed for larvae and juveniles needs to be further explored. On the other hand, existing studies have shown that the growth rate and survival rate of larvae and juveniles can be improved by feeding nutrient-enhanced live baits, such as feeding fortified eicosapentaenoic acid and docosahexaenoic acid. Artemia. Moreover, studies have also found that different nutrient-enriched baits have different effects on the growth and survival of fish. For example, Du Tao et al. (2010) carried out nutrition-intensive nursery experiments on barramundi, pomfret and American redfish with yeast rotifers and rotifers enhanced with chlorella and spirulina. The survival rate of larvae and juveniles in the fortified rotifers with cocci and spirulina powder was significantly higher than that in the yeast group. However, most of the researches are aimed at nutritional fortification of live baits, and how to carry out nutritional fortification of artificial diets for larvae and juveniles still needs further research and development. Qin Zhiqing et al. (2020) raised 5-day-old Acrossocheilius hemispinus larvae that had just opened their mouths to feed in glass tanks of 60cm×50cm×50cm at a density of 300 fish/tank, and fed freshwater rotifers (10ind./mL ), water worm slurry (passed through a 150 μm sieve), egg yolk (rubbed with 250 μm gauze), fry feed and shrimp milk powder, after 22 days of breeding experiments, it was found that freshwater rotifers are the most suitable feed for semi-spined larvae; Water worm slurry is suitable for opening bait, and it can be used as an alternative for opening bait for the larvae of the larvae when there is a lack of freshwater rotifers, which shows that the current artificial bait cannot fully meet the growth needs of larvae. Therefore, it is necessary to develop a nutritional enhancer that strengthens the larva opening feed, so as to be more conducive to the larvae opening directly with feed, and to improve the growth and survival rate of the larvae.

Contents of the invention

The present invention aims at the characteristics of small individual fish, weak mobility, poor ability to adapt to the external environment, and underdeveloped digestive system, and provides a method that can promote the direct intake of artificial compound feed by juvenile fish during the opening stage, and significantly improve the growth of juvenile fish. and survival rate nutritional enhancer. The ingredients of the nutritional supplement include eicosapentaenoic acid, docosahexaenoic acid, eicosadonic acid, protease, lipase, amylase, vitamin C, lecithin, taurine, lysine wait.

Another object of the present invention is to provide the application of the above nutritional enhancer as a feed additive for larvae and juvenile fish.

To achieve the above object, the present invention is achieved through the following technical solutions:

A nutritional enhancer for larvae and juvenile fish feed, which consists of the following components in parts by weight: 2-8 parts of eicosapentaenoic acid, 4-16 parts of docosahexaenoic acid, and 4-16 parts of eicosatraenoic acid 0.1-1 parts, 4-12 parts of compound enzyme preparation, 2-10 parts of vitamin C, 40-120 parts of lecithin, 7-15 parts of taurine, 15-25 parts of lysine.

Each part of the compound enzyme preparation contains 10000-30000U of protease, 8000-15000U of lipase and 10000-30000U of amylase.

In the scheme described above, preferably, 3-6 parts of eicosapentaenoic acid, 6-10 parts of docosahexaenoic acid, 0.3-0.7 parts of eicosatraenoic acid, 5-10 parts of compound enzyme preparation 4-8 parts of vitamin C, 70-90 parts of lecithin, 10-12 parts of taurine, 15-18 parts of lysine.

The scope of protection of the present invention also includes: the application of the above nutritional enhancer in the preparation of feed additives for larvae and juveniles; the additive can improve the body length, weight and survival rate of larvae and juveniles.

In the above application, preferably, the larvae are larvae.

Compared with the prior art, the present invention has the following advantages:

The invention provides a nutritional enhancer for larvae and juvenile fish mouth feed and its application. The feed additive provided by the invention has easy-to-obtain raw materials and a simple production process, which can promote the direct feeding of feed by larvae and juveniles in the opening stage, further improve the digestibility of larvae and juveniles, effectively supplement the needs of larvae and juveniles for external nutrients, and improve the nutritional value of larvae and juveniles. Juvenile fish grow, increase immunity, and improve survival rate.

Description of drawings

Figure 1 is a schematic diagram of the change in body length of juvenile sturgeon fed with different feeds.

Figure 2 is a schematic diagram of the body weight change of juvenile sturgeon fed with different feeds.

Figure 3 is a schematic diagram of the survival rate of sturgeon larvae.

Figure 4 is a schematic diagram of the body length change of largemouth bass juveniles fed with different feeds.

Figure 5 is a schematic diagram of the body weight changes of largemouth bass juveniles fed with different feeds.

Figure 6 is a schematic diagram of the survival rate of juvenile largemouth bass.

Fig. 7 is a schematic diagram of the body length change of the juvenile yellow catfish larvae fed with different feeds.

Fig. 8 is a schematic diagram of the body weight change of the juvenile peltedelachus larvae fed with different feeds.

Fig. 9 is a schematic diagram of the survival rate of larvae and juveniles of yellow catfish.

Figure 10 is a schematic diagram of body length changes of sturgeon larvae fed with different feeds.

Figure 11 is a schematic diagram of body weight changes of sturgeon larvae and juveniles fed with different feeds.

Figure 12 is a schematic diagram of the survival rate of sturgeon larvae.

Detailed ways

The present invention will be further described below in conjunction with specific examples, but the present invention is not limited by the examples. The technical solutions described in the present invention are conventional solutions in the art unless otherwise specified. The reagents or materials described in the present invention, unless otherwise specified, are all derived from commercial channels.

In the embodiment of the present invention, each part of the compound enzyme preparation contains 20000 U of protease, 10000 U of lipase and 20000 U of amylase.

Example 1:

A feed additive for strengthening the nutrition of juvenile fish, which is composed of the following components in parts by weight: 3 parts of eicosapentaenoic acid, 6 parts of docosahexaenoic acid, 0.3 part of eicosatetraenoic acid, compound enzyme 5 parts of the preparation, 4 parts of vitamin C, 70 parts of lecithin, 10 parts of taurine, and 15 parts of lysine can be mixed according to the conventional method.

Example 2:

A feed additive for strengthening the nutrition of juvenile fish, which is composed of the following components in parts by weight: 4 parts of eicosapentaenoic acid, 8 parts of docosahexaenoic acid, 0.5 part of eicosatetraenoic acid, compound enzyme 7 parts of the preparation, 6 parts of vitamin C, 80 parts of lecithin, 11 parts of taurine, and 16 parts of lysine can be mixed according to the conventional method.

Example 3:

A feed additive for strengthening the nutrition of juvenile fish, which is composed of the following components in parts by weight: 6 parts of eicosapentaenoic acid, 10 parts of docosahexaenoic acid, 0.7 part of eicosatetraenoic acid, compound enzyme 10 parts of the preparation, 8 parts of vitamin C, 90 parts of lecithin, 12 parts of taurine, and 18 parts of lysine can be mixed according to the conventional method.

Example 4:

Application of nutrient enhancer for larvae and juvenile fish feed in sturgeon larvae and juvenile fish feed:

1. Test Feed

4 kinds of feeds are water earthworms (the most commonly used biological feed for cultivating juvenile sturgeon), a certain brand of sturgeon feed (abbreviated as A brand, common in the market), and the A brand sturgeon of Example 1 with a weight ratio of 1%. Opening material, add the A brand sturgeon opening material of 1.2% embodiment 2 by weight.

2. Pilot Fish and Culture System

The 6-day-old sturgeon larvae were used in the experiment, which is the most important domestically cultured sturgeon hybrid (Acipenserbaerii♀×A.schrenckii♂), which was sourced from a professional sturgeon breeding farm in Beijing.

The test was carried out in 12 circular culture tanks, with flowing water culture, the water source was groundwater, the water temperature was 18.9-20.2°C, the pH was 7.1-8.0, and DO≥9mg/L. The diameter of the breeding tank is 1.5m, and the water depth is 40cm. 1000 larvae and juveniles are stocked in each bucket.

3. Test management

After the 6-day-old hybrid sturgeon larvae entered the system, a small number of seedlings began to stick to the bottom and cluster. At the age of 7 days, the larvae had clustered, part of the yolk had been absorbed, and the embolus began to drain. Therefore, the daily feeding amount is 60% of body weight, and the daily feeding amount is 30-40% of body weight after 10 days of age, and 20-30% of body weight after 15 days of age. Feed 6 times a day with an interval of 4 hours. Water earthworms are pulped with a meat grinder and sprinkled in the whole bucket, and the feed is fed with water and mixed with the whole bucket for each meal.

4. Test indicators

Body length and weight measurement: randomly select 30 representative fry every 5 days, measure the body length with a vernier caliper, and measure the weight of the fry with a one-thousandth balance.

Survival rate (%) = [(number of fish tails at the beginning of the test - number of fish tails at the end of the test)/number of fish tails at the beginning of the test] × 100%

5. Experimental results

5.1 Effects of different opening feeds on the body length of sturgeon larvae

It can be seen from Figure 1 that during the 25-day culture period, the juvenile sturgeon fed with different feeds had different degrees of growth in body length, and the juvenile sturgeon fed with water earthworms had the largest increase in body length; Among the three groups, there was no significant difference in the previous 15d, but the growth of the juvenile body length of the sturgeon larvae fed with the feed of Example 1 and Example 2 was better than that of A brand at 20d, showing that the application of Example 1 and implementation The additive in Example 2 is more conducive to the increase of the body length of juvenile sturgeon.

5.2 Effects of different opening feeds on the body weight of juvenile sturgeon

As can be seen from Figure 2, water earthworms are the most beneficial to the weight gain of juvenile sturgeon; compared with the A brand feed, feeding the feed of Example 1 and Example 2 is more conducive to the weight gain of juvenile sturgeon, indicating that the application of The additives of Example 1 and Example 2 are more conducive to the body weight growth of juvenile sturgeon.

5.3 Effects of different opening feeds on the survival rate of juvenile sturgeon

It can be seen from Figure 3 that feeding the feed containing the additives of Example 1 and Example 2 can make the survival rate of the juvenile sturgeon reach the effect similar to that of feeding water earthworms, which is significantly higher than that of only feeding A brand feed of. Show that application embodiment 1 and the additive of embodiment 2 are more conducive to the survival of juvenile sturgeon.

Example 5:

The application of nutrient enhancer in feed for larvae and juveniles in juvenile largemouth bass feed:

1. Test Feed

4 kinds of feeds, namely red worms (the most commonly used biological feed for juvenile largemouth bass, collected from ponds through dense nets), a certain brand of largemouth bass juvenile feed (referred to as B brand, common in the market), Add the B brand largemouth bass juvenile feeding feed of 0.8% by weight ratio of embodiment 2, add the B brand largemouth bass juvenile feeding feed of 1.5% embodiment 3 by weight ratio.

2. Pilot Fish and Culture System

The experiment selected 4-day-old largemouth bass juveniles from a large-scale fry farm of largemouth bass in Guangdong. The test was carried out in 12 circular culture tanks, with circulating water culture, water temperature 23.5-25.5°C, pH 6.8-7.2, DO≥5mg/L. The diameter of the breeding tank is 1.2m, and the water depth is 80cm. 1500 larvae and juveniles are stocked in each barrel. The breeding system uses shaded fluorescent lamps as the light source, the photoperiod is daytime: 12:12 nighttime, and the light intensity is about 400Lux.

3. Test management

Juvenile largemouth bass were fed the experimental feed on the second day after they were placed in the recirculating aquaculture system. Clap your hands before feeding each time to facilitate the test fish to form a conditioned reflex. Feed 4 times a day with an interval of 6 hours. Red worms are directly poured into the breeding tank, and the feed is fed with water and mixed with the whole tank for each meal. The feeding rate is the same as in Example 4.

4. Test indicators

Body length and weight measurement: 30 representative fry were randomly selected in the experiment on 5d, 10d, 20d and 30d after feeding, the body length was measured with a vernier caliper, and the weight of the fry was measured with a thousandth balance.

Survival rate (%) = [(number of fish tails at the beginning of the test - number of fish tails at the end of the test)/number of fish tails at the beginning of the test] × 100%

5. Experimental results

5.1 Effects of different feeding materials on the body length of juvenile largemouth bass

As can be seen from Figure 4, red worms are the most beneficial to the growth of the body length of largemouth bass juveniles, but compared with the B brand mouth feed, adding Example 2 and Example 3 to it can increase the body length of larvae and juveniles increase.

5.2 Effects of different feeding materials on the body weight of juvenile largemouth bass

It can be seen from Figure 5 that red worms are most beneficial to the weight gain of largemouth bass juveniles, but compared with B brand feed, adding Example 2 and Example 3 can improve the weight gain of larvae and juveniles.

5.3 Effects of different opening feeds on the survival rate of juvenile largemouth bass

As can be seen from Figure 5, the survival rate of largemouth bass juveniles fed with red worms is the highest, but compared with B brand mouth feed, adding Example 2 and Example 3 can improve the survival rate of larvae and juveniles .

Embodiment 6:

Application of nutrient enhancer for open feed of larvae and juveniles in feed for larvae and juveniles of yellow catfish:

1. Test Feed

4 kinds of feeds, namely red worm (the most commonly used biological feed for cultivating yellow catfish larvae juveniles, collected from ponds through dense nets), a certain brand of yellow catfish juvenile feed (referred to as C brand, common in the market), Add the C brand peltago larva juvenile feed of the embodiment 1 of weight ratio 1.0%, add the C brand peltago larva juvenile feed of the C brand larvae juvenile fish of the embodiment 3 with the weight ratio 0.9%.

2. Pilot Fish and Culture System

Two-day-old yellow catfish larvae were used in the experiment, which were sourced from a large-scale seedling farm of yellow catfish in Hubei. The test was carried out in 12 circular culture tanks, with circulating water culture, water temperature 27.0-29.0°C, pH 6.5-7.5, DO≥5mg/L. The diameter of the breeding tank is 1.2m, and the water depth is 80cm. 1000 larvae and juveniles are stocked in each bucket. The breeding system uses shaded fluorescent lamps as the light source, the photoperiod is daytime: 12:12 nighttime, and the light intensity is about 400Lux.

3. Test management

Peeled catfish juveniles were fed the experimental feed on the second day after they were put into the recirculating aquaculture system. Clap your hands before feeding each time to facilitate the test fish to form a conditioned reflex. Red worms are directly poured into the breeding tank, and the feed is fed with water and mixed with the whole tank for each meal. The feeding rate is the same as in Example 4.

4. Test indicators

Body length and weight measurement: 30 representative fry were randomly selected in the experiment on 5d, 10d, 15d and 25d after feeding, the body length was measured with a vernier caliper, and the weight of the fry was measured with a thousandth balance.

Survival rate (%) = [(number of fish tails at the beginning of the test - number of fish tails at the end of the test)/number of fish tails at the beginning of the test] × 100%

5. Experimental results

5.1 Effects of different feeding materials on the body length of juvenile yellow catfish larvae

It can be seen from Figure 7 that feeding red worms is most conducive to the growth of the juvenile body length of yellow catfish larvae. Compared with feeding C brand feed, feeding the addition of Example 1 and Example 3 increased the body length growth of larvae.

5.2 Effects of different opening feeds on the body weight of juvenile yellow catfish larvae

It can be seen from Figure 8 that feeding red worms is most beneficial to the weight increase of yellow catfish. Compared with feeding C brand feed, the addition of Example 1 and Example 3 in the feed is more conducive to the increase in body weight of larvae and juveniles of yellow catfish.

5.3 Effects of different opening feeds on the survival rate of juvenile yellow catfish larvae

As can be seen from Figure 9, the survival rate of juvenile yellow catfish larvae fed with red worms was the highest. Compared with feeding the C brand feed, the survival rate of the juvenile yellow catfish fed with the feed of Example 1 and Example 3 was higher.

Embodiment 7:

Different nutrient fortifiers are used in the feed of sturgeon larvae

Comparing the survival rate of Example 4, Example 5 and Example 6, we can know that in the application of sturgeon, yellow catfish and largemouth bass, the nutritional fortifier of larval fish opening feed has the highest percentage in the sturgeon larval fish feed. The application effect is better. Further compare the promoting effect of the nutrient enhancer of the larva opening feed of the present invention and other mixtures that can be used for the enhancer in the sturgeon larvae:

1. Test Feed

5 kinds of feeds are water earthworms (the most commonly used biological feed for cultivating juvenile sturgeon), a certain brand of sturgeon feed (abbreviated as A brand, common in the market), and the A brand sturgeon of Example 1 with a weight ratio of 1.2%. Opening material, the A brand sturgeon opening material of comparative example 1 with 1.2% by weight added, the A brand sturgeon opener material of comparative example 2 with 1.2% by weight added, and the A brand of comparative example 3 added respectively according to the published literature Sturgeon mouth feed.

The components of Comparative Example 1 are as follows, in parts by weight, 3 parts of eicosapentaenoic acid, 7 parts of docosahexaenoic acid, 0.2 parts of eicosatetraenoic acid, and 55 parts of phospholipids, mixed according to conventional methods.

The components of Comparative Example 2 are as follows, in parts by weight, consisting of the following components in parts by weight: 8 parts of eicosapentaenoic acid, 8 parts of docosahexaenoic acid, 8 parts of eicosatetraenoic acid, compound 20 parts of enzyme preparation, 15 parts of vitamin C, 100 parts of lecithin, 20 parts of taurine, 30 parts of lysine, mixed according to conventional methods.

Comparative example 3 is that in the mouth feed of A brand A sturgeon larvae per kilogram, the addition amounts of various components are: 1.87g of eicosapentaenoic acid (Luo, 2019), 0.8g of docosahexaenoic acid ( Luo, 2019), eicosatetraenoic acid 0.023g (Luo, 2019), protease 225U (Ghodrati, 2021), lipase 6000U (Ran, 2015), amylase 3457U (Hlophe, 2016), vitamin C 300mg (high strength , 2006), lecithin 60g (Fatemeh, 2018), taurine 1g (Hoseini, 2018), lysine 30g (Foshtomi, 2016).

2. Pilot Fish and Culture System

The 6-day-old sturgeon larvae were used in the experiment, which is the most important domestically cultured sturgeon hybrid (Acipenserbaerii♀×A.schrenckii♂), which was sourced from a professional sturgeon breeding farm in Beijing.

The test was carried out in 18 circular culture tanks, and the water source was groundwater, the water temperature was 18.9-20.2°C, the pH was 7.1-8.0, and DO≥9mg/L. The diameter of the breeding tank is 1.5m, and the water depth is 40cm. 1000 larvae and juveniles are stocked in each bucket.

3. Test management

With embodiment 4.

4. Test indicators

With embodiment 4.

5. Experimental results

5.1 Effects of different opening feeds on the body length of sturgeon larvae

It can be seen from Figure 10 that feeding water earthworms is most beneficial to the growth of juvenile sturgeon larvae. Compared with feeding brand A feed, feeding Example 2 and Comparative Example 3 promoted body length growth, but Comparative Example 2 was significantly higher than Comparative Example 3.

5.2 Effects of different opening feeds on body weight of sturgeon larvae

It can be seen from Figure 11 that feeding water earthworms is the most beneficial to increase the body weight of sturgeons, adding Example 2 to the feed can achieve a similar body weight as feeding water earthworms. Compared with feeding the A brand feed, the body weight of Comparative Example 1 and Comparative Example 2 decreased slightly, while that of Comparative Example 3 increased, but far less than that of Example 2.

5.3 Effects of different opening feeds on the survival rate of sturgeon larvae

It can be seen from Figure 12 that the juvenile sturgeon larvae fed with water earthworms had the highest survival rate, and adding Example 2 to the feed could achieve a survival rate similar to that achieved by feeding with water earthworms. But feeding Comparative Example 1, Comparative Example 2 and Comparative Example 3 did not reach a similar survival rate.

From the comparison of the above results, it can be seen that the feed additive of the present invention can effectively increase the survival rate of larvae and juvenile fish, improve growth, and further effectively reduce the application of live bait.

The above implementations are exemplary and should not be construed as limitations on the present invention. Those skilled in the art can change, modify, replace, etc. the above embodiments within the scope of the present invention, all of which belong to the protection scope of the present invention.

Claims (6)

1. A nutritional enhancer for larvae and juvenile fish mouth feed, consisting of the following components by weight: 2-8 parts of eicosapentaenoic acid, 4-16 parts of docosahexaenoic acid, eicosapentaenoic acid 0.1-1 part of enoic acid, 4-12 parts of compound enzyme preparation, 2-10 parts of vitamin C, 40-120 parts of lecithin, 7-15 parts of taurine, and 15-25 parts of lysine. 2. The nutrition enhancer according to claim 1, wherein each part of said compound enzyme preparation contains 10000-30000 U of protease, 8000-15000 U of lipase and 10000-30000 U of amylase. 3. The nutrition enhancer according to claim 1, characterized in that: 3-6 parts of eicosapentaenoic acid, 6-10 parts of docosahexaenoic acid, 0.3-0.7 parts of eicosatraenoic acid , 5-10 parts of compound enzyme preparation, 4-8 parts of vitamin C, 70-90 parts of lecithin, 10-12 parts of taurine, 15-18 parts of lysine. 4. The application of the nutritional enhancer according to claim 1 in the preparation of feed additives for larvae and juveniles. 5. The application according to claim 4, wherein said additive improves body length, body weight and survival rate of juvenile fish. 6. The application according to claim 4, wherein the larvae are larvae.

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