CN112175846B - Candida utilis strain UCY-11 and application thereof in preparation of fermented hybrid broussonetia papyrifera feed - Google Patents

Abstract

The invention relates to a Candida utilis strain UCY-11 and its application in preparing fermented hybrid paper mulberry feed, which can effectively solve the problem of using the strain to prepare fermented hybrid paper mulberry feed, degrade macromolecular proteins contained in the feed, and improve the The content of crude protein and peptides in crude protein can reduce the content of anti-nutritional factors such as cellulose and lignin, improve the nutritional value of its feed, and meet the actual needs of animal husbandry. Ultraviolet mutagenesis technology is used to obtain Candida utilis strain UCY ‑11, the use of this strain to ferment the hybrid paper mulberry feed can effectively increase the crude protein and the content of peptides in the crude protein, improve the nutritional quality of the hybrid paper mulberry feed, and improve the utilization efficiency of the hybrid paper mulberry feed by animals. It is also beneficial to improve the intestinal microecological balance of animals, promote the development of animal health and aquaculture, and meet the needs of animal protein in people's lives, which has significant economic and social benefits.

Description

A strain of Candida utilis UCY-11 and its application in the preparation of fermented hybrid paper mulberry feed

technical field

The invention relates to the field of microorganisms, in particular to a Candida utilis strain UCY-11 and its application in preparing fermented hybrid paper mulberry feed.

Background technique

With the rapid development of my country's economy and the continuous improvement of people's living standards, the demand for animal protein is increasing day by day, and the contradiction between supply and demand has become increasingly prominent. Animal protein mainly comes from animal husbandry. Animal husbandry is an important part of modern agriculture in my country and an important source of meat, eggs and milk food. Vigorously developing crude protein plant feed resources has become a new way to alleviate the shortage of protein feed raw materials and ensure food safety. .

Hybrid paper mulberry is a new paper mulberry variety cultivated by the Institute of Botany, Chinese Academy of Sciences using modern biotechnology and traditional hybrid breeding methods. , the corner can be planted. Hybrid paper mulberry has the characteristics of fast growth and high yield, high crude protein content, and is a green and efficient source of vegetable protein feed. Hybrid paper mulberry is rich in crude protein, crude fat, amino acids, vitamins, carbohydrates and trace elements. The crude protein content in leaves is 2 times that of wheat, 3 times that of corn and rice, and the crude fat content is 2 times that of rice and wheat. , the total amino acid content exceeds 20%, and the essential amino acids account for about 40% of the total amino acids. However, due to the complex protein structure and high content of lignin and cellulose in mature hybrid leaves and branches, monogastric animals are difficult to digest and absorb, which reduces the utilization rate of their nutrients by livestock and poultry. Studies have shown that microbial fermentation treatment can significantly improve the digestibility of hybrid paper mulberry feed. Microorganisms can decompose the complex structure of hybrid paper mulberry protein into short peptides and amino acids that are easy to digest and absorb, and at the same time can improve crude protein and crude protein. The content of peptides , reduce the content of anti-nutritional factors such as cellulose and lignin.

Candida utilis , also known as Torula utilis or edible Torula utilis, is a simple morphological structure, mainly budding, large cells, vigorous metabolism, fast growth and reproduction, and strong adaptability to the environment , suitable for a variety of different bioreactors for fermentation of fungi. Candida utilis cells are generally 3.5μm～4.5μm×7.0μm～13.0μm, round, oval or sausage-shaped, and reproduce asexually by multilateral budding to form pseudohyphae. Candida utilis is widely used in food because it is rich in proteins, lipids, sugars and various vitamins, and also produces enzymes, coenzymes, ribonucleic acids, sterols and some metabolic intermediates during the fermentation process. , medicine, experimental research, animal husbandry and feed industries.

As a high-yielding protein biological source, Candida utilis itself is also a beneficial bacterium in the animal intestine. It has many functions in maintaining the balance of animal intestinal flora, improving immunity, providing nutrients for animals, and improving daily weight gain. Very good application value. At present, the research on Candida utilis mainly focuses on its selenium-enriched function, the production of single-cell protein feed by fermentation and culture of Candida utilis, and its use as a beneficial bacteria in the animal intestine, which is beneficial to maintaining the balance of animal intestinal flora and providing animals with However, there is no report on the fermented hybrid paper mulberry feed of Candida utilis. Therefore, it is very important to screen a new strain of Candida utilis with the function of fermenting hybrid paper mulberry feed.

SUMMARY OF THE INVENTION

In view of the above situation, in order to overcome the defects of the prior art, the purpose of the present invention is to provide a Candida utilis strain UCY-11 and its application in the preparation of fermented hybrid paper mulberry feed, which can effectively solve the problem of using the strain to prepare fermentation Hybrid paper mulberry feed can degrade the macromolecular protein contained in the feed, increase the content of crude protein and peptides in crude protein, reduce the content of anti-nutritional factors such as cellulose and lignin, improve the nutritional value of its feed, and meet the actual needs of animal husbandry. question.

The technical solution solved by the present invention is that a strain of Candida utilis UCY-11 is classified and named as Candida utilis , the preservation number is CGMCC No. 19132, and the preservation unit: China Microorganism Culture Collection Management General Microbiology Center of the Committee, Address: No. 3, Yard 1, Beichen West Road, Chaoyang District, Beijing, preservation date: December 16, 2019;

The strain can be effectively used for preparing fermented hybrid paper mulberry feed, and the method includes the following steps:

(1) Preparation of seed liquid: The Candida utilis strain UCY-11 was cultured in the fermented seed liquid medium, and the fermented seed liquid was obtained by culturing it in a fermented seed Erlenmeyer flask. The speed is 10～15r/min;

The fermented seed liquid medium is prepared by dissolving 20.0 g of glucose, 10.0 g of peptone and 5.0 g of yeast extract in 1 L of deionized water, and sterilized at 121° C. for 15 minutes;

(2) Preparation of fermented hybrid paper mulberry medium: the medium is calculated by the following mass percentages: 65-75% of hybrid paper mulberry dry powder, 5-15% of corn flour, 4-6% of wheat bran, 4-6% of rice bran 6%, molasses 5-15% and inorganic salt 0.1-0.3%, the total amount is 100%, mix well, add water to make the mass water content (m/m) reach 55-60%;

Described inorganic salt is a kind of in ammonium salt, magnesium salt, sodium salt, potassium salt;

(3) Preparation of fermented hybrid paper mulberry feed: inoculate the fermented seed liquid into the fermented hybrid paper mulberry medium according to the inoculation quality of 8-10%, put it into a triangular flask for fermentation and culture, and the loading amount is 30% of the volume of the triangular flask. 30～50%, fermented for 48～72h under the condition of temperature 32～36℃, to obtain fermented hybrid paper mulberry wet feed;

(4) Drying: Dry the fermented hybrid paper mulberry wet feed under the condition of ≤60°C to a mass water content of ≤12%, pulverize, and pass through a 40-60 mesh sieve, which is the finished product.

In the present invention, the Candida utilis strain UCY-11 is obtained by the ultraviolet mutagenesis technology, and the hybrid paper mulberry feed is fermented by using the strain, which can effectively increase the crude protein and the content of peptides in the crude protein, and improve the quality of the hybrid paper mulberry feed. Nutritional quality, improve the utilization efficiency of hybrid paper mulberry feed, and also help to improve the intestinal microecological balance of animals, promote the development of animal health and aquaculture, and meet the needs of animal protein in people's lives. It has significant economic and social benefit.

Detailed ways

The specific embodiments of the present invention will be described in detail below with reference to the examples.

The specific implementation of the present invention can be given by the following examples.

Example 1

(1) Preparation of seed liquid: The Candida utilis strain UCY-11 was cultured in the fermented seed liquid medium, and the fermented seed liquid was obtained by culturing it in a fermented seed Erlenmeyer flask. 12r/min;

(2) Preparation of fermented hybrid paper mulberry medium: the medium is calculated by the following mass percentages: 69% of hybrid paper mulberry dry powder, 10% of corn flour, 5.4% of wheat bran, 5.4% of rice bran, 10% of molasses and inorganic 0.2% salt, the total amount is 100%, mix evenly, and add water to make its mass water content reach 55-60%;

(3) Preparation of fermented hybrid paper mulberry feed: the fermented seed liquid is inoculated into the fermented hybrid paper mulberry medium according to the inoculation quality of 9%, and put into a triangular flask for fermentation culture, and the loading amount is 40% of the volume of the triangular flask. Fermentation for 60 hours at a temperature of 34°C to obtain wet feed of fermented hybrid paper mulberry;

(4) Drying: Dry the fermented hybrid paper mulberry wet feed under the condition of ≤60°C to a mass water content of ≤12%, pulverize it, and pass it through a 50-mesh sieve, which is the finished product.

Example 2

The method that a Candida utilis strain UCY-11 of the present invention is applied in the preparation of fermented hybrid paper mulberry feed is as follows:

(1) Preparation of seed liquid: The Candida utilis strain UCY-11 was cultured in the fermented seed liquid medium, and the fermented seed liquid was obtained by culturing it in a fermented seed Erlenmeyer flask. 11r/min;

(2) Preparation of hybrid paper mulberry trunk powder: from a planting base in Henan. In early June, when the whole plant of hybrid paper mulberry grows to a height of 1.0-1.2 m, the first crop is harvested, leaving 15-20 cm of stubble, and the whole plant is dried and crushed To 20～40 meshes, get hybrid paper mulberry trunk powder;

(3) Preparation of fermented hybrid paper mulberry medium: the medium is made by adding 375 kg of hybrid paper mulberry dry powder, 30 kg of corn flour, 25 kg of wheat bran, 25 kg of rice bran, 50 kg of molasses and 1.5 kg of inorganic salts into a 1-ton mixer to mix Evenly, add water to make its mass water content reach 56%;

Corn flour, wheat bran and rice bran are commercially available products and meet the relevant national standards for feed raw materials; the main component of molasses is sucrose, a reddish-brown viscous liquid, the mass content of dry matter is 48.98%, and the mass content of water-soluble sugar is 64.8%, which is in line with QB/ T2684-2005 standard;

(4) Preparation of fermented hybrid paper mulberry feed: inoculate 45 L of the fermented seed liquid into the fermented hybrid paper mulberry medium, fully mix it in a mixer for 1 hour, and put it into a film bag with a breathing valve, 20 kg or 25 kg per bag, and seal it. , and fermented for 48-72 hours at a temperature of 32-36° C. to obtain wet feed of fermented hybrid paper mulberry.

Example 3

The method that a Candida utilis strain UCY-11 of the present invention is applied in the preparation of fermented hybrid paper mulberry feed is as follows:

(1) Preparation of seed liquid: The Candida utilis strain UCY-11 was cultured in the fermented seed liquid medium, and the fermented seed liquid was obtained by culturing it in a fermented seed Erlenmeyer flask. 14r/min;

(2) Preparation of hybrid paper mulberry trunk powder: from a planting base in Henan. In early June, when the whole plant of hybrid paper mulberry grows to a height of 1.0-1.2 m, the first crop is harvested, leaving 15-20 cm of stubble, and the whole plant is dried and crushed To 20～40 meshes, get hybrid paper mulberry trunk powder;

(3) Preparation of fermented hybrid paper mulberry medium: the medium is calculated by the following mass percentages: 3500 g of hybrid paper mulberry dry powder, 500 g of corn flour, 250 g of wheat bran, 250 g of rice bran, 500 g of molasses and 15 g of inorganic salt are mixed evenly , add water to make its mass water content (m/m) reach 58%;

Corn flour, wheat bran and rice bran are commercially available products and meet the relevant national standards for feed raw materials; the main component of molasses is sucrose, a reddish-brown viscous liquid, with a dry matter content of 48.98% and a water-soluble sugar content of 64.8%, in line with QB/T2684- 2005 standard;

(4) Preparation of fermented hybrid paper mulberry feed: the fermented seed liquid is inoculated into the fermented hybrid paper mulberry medium according to the inoculation quality of 10%, and put into a triangular flask for fermentation culture, and the loading amount is 50% of the volume of the triangular flask. Fermentation at a temperature of 34°C for 72h to obtain wet feed of fermented hybrid paper mulberry;

(5) Drying: Dry the fermented hybrid paper mulberry wet feed at ≤60°C to a mass water content of ≤12%, pulverize it, and pass it through a 40-60 mesh sieve, which is the fermented hybrid paper mulberry dry powder feed.

The fermented hybrid paper mulberry feed prepared by the method of the invention has been tested and applied, and the effect is very good. The relevant information is as follows:

1. Obtainment of Candida utilis UCY-11:

Ultraviolet mutagenesis of the native Candida utilis strain: take 0.1 mL of the culture solution of the Candida utilis strain activated by the plate medium and spread it on the primary screening plate, cultivate at 28 °C for 6 hours, and pre-heat the cells with ultraviolet light. Heat for 30min, place the primary screening plate at a distance of 30cm from a 15W UV lamp and irradiate it for 0min, 3min, 6min, 9min, 12min, and 15min, respectively, and elute the primary screening plate with 5mL sterile saline under dark light conditions. , coated on the plate medium, cultured at 28°C for 84 hours, and screened according to the size of the colony and the transparent circle; according to the shape of the mutant strain colony, the size of the colony and the size of the transparent circle, 20 strains were selected and fermented in the triangular flask. Hybrid paper mulberry feed, re-screened according to crude protein and peptide content in crude protein, cultured at 28°C for 66 hours, and measured the crude protein and peptide content in fermented culture, among which the most significant increase is the target. Strain, according to the morphological characteristics, culture characteristics, physiological and biochemical characteristics and molecular biological characteristics of the target strains selected for UV mutagenesis, the identification of the mutant strain UCY-11;

Morphological characteristics of strains

Observed under the microscope, the strain UCY-11 is oval in shape, with a small amount of circular shape, and the size is 3.2μm～4.4μm×7.3μm～12.8μm. It reproduces asexually by multilateral budding, producing pseudohyphae, no sexual spores, and no pigment. produce.

strain culture characteristics

After the strain UCY-11 was cultured on wort agar plate medium at 28℃ for 72h, the cultured colonies were protruding, thick and large, and the colony diameter was 0.6-1.8cm. Colonies are white, smooth, glossy or matt, with neat edges or mycelium. The color of the front and back, edges and central parts of the colonies is the same. The colony is uniform in texture and has villi-like hyphae on the surface, which are easy to provoke. Glucose, peptone, yeast extract liquid medium was cultured at 28°C for 72h, the surface was sterile membrane, the medium was turbid, and there was bacterial precipitation at the bottom of the tube.

Physiological and biochemical characteristics of strains

Strain UCY-11 can utilize five-carbon and six-carbon sugars and other monosaccharides, such as glucose, xylose, etc., but cannot utilize maltose, galactose, lactose, etc. Carbon source assimilation test, D-glucose, D-galactose, D-xylose, sucrose, maltose, etc. were positive, L-arabinose, lactose, etc. were negative. Strain UCY-11 grows well on vitamin-free medium. The medium strain UCY-11 can grow with urea and nitric acid as nitrogen sources. Strain UCY-11 can ferment and utilize plant materials such as soybean meal, wheat bran and corn flour to produce single-cell protein products.

Molecular biological characteristics of strains

Strain UCY-11 was amplified by PCR with the 18S rDNA 5' end universal primer ITS1 (P1) and the 5' end characteristic primer CU (P2) in the ITS2 region, and a characteristic fragment of 449 bp appeared. After the 18S rDNA 5' end universal primer ITS1 ( P1) and 28 S rDNA 3'-terminal universal primer (P3) after PCR amplification, a 565bp characteristic fragment gene appeared, which was different from other fungi.

According to the morphological characteristics, culture characteristics, physiological and biochemical characteristics and molecular biological characteristics of the strain UCY-11 bred by ultraviolet mutagenesis, the strain UCY-11 belongs to Candida utilis and is classified and named as Candida utilis , numbered as Candida utilis strain UCY-11. Preserved in the General Microbiology Center of the China Microorganism Culture Collection Management Committee, address: No. 3, No. 1, Beichen West Road, Chaoyang District, Beijing, preservation date: December 16, 2019, preservation number: CGMCCN0.19132.

The strain is effectively used for preparing fermented hybrid paper mulberry feed, and realizes the application of Candida utilis strain UCY-11 in preparing fermented hybrid paper mulberry feed.

2. Determination method of feed composition of hybrid paper mulberry

The content of crude protein, crude fat and crude fiber in hybrid paper mulberry feed and hybrid paper mulberry fermented culture were determined according to the methods of GB/T6432-1994, GB/T6433-2006 and GB/T6434-2006, respectively. The content of peptides was determined according to the method of QB/T2653-2004, and the viable count of Candida utilis was determined according to the standard of NY/T1969-2010.

3. The effect of fermentation on the feed composition of hybrid paper mulberry

By measuring the contents of crude protein, peptide, crude fat, crude fiber and the viable count of Candida utilis in the fermented hybrid paper mulberry feed, the changes of the nutrient content and viable count of the hybrid paper mulberry feed before and after fermentation were compared. The test results are shown in Table 1. Table 1 shows that the crude protein content in the fermented hybrid paper mulberry feed increased from 18.25% before fermentation to 20.68%, an increase of 13.15%. The content of peptides in crude protein in fermented hybrid paper mulberry feed increased from 7.35% before fermentation to 8.56%, an increase of 16.46%. The crude fat content in the fermented hybrid paper mulberry feed increased from 5.48% before fermentation to 5.56%, an increase of 1.46%. The crude fiber content in the fermented hybrid paper mulberry feed decreased from 29.74% before fermentation to 21.01%, a decrease of 29.35%. The viable count of Candida utilis in the fermented hybrid paper mulberry feed is ≥1 billion/g.

Table 1 Changes of components of hybrid paper mulberry feed before and after fermentation project Crude protein content (%) Peptide content (%) Crude fat content (%) Crude fiber content (%) Viable count of Candida utilis (pcs/g) Before fermentation 18.25 7.35 5.48 29.74 0 after fermentation 20.68 8.56 5.56 21.01 ≥1 billion

4. Function and effect of fermented hybrid paper mulberry feed

The protein structure of hybrid paper mulberry feed is complex, and it is difficult for livestock and poultry to digest and absorb, and the rich crude protein resources have not been fully developed and utilized, resulting in serious waste of resources. The treatment of hybrid paper mulberry feed with Candida utilis fermentation technology can not only degrade macromolecular protein with complex structure in paper mulberry feed, but also significantly increase the content of crude protein and peptides in crude protein, and improve the crude protein in hybrid paper mulberry feed. The nutritional value and the digestion and absorption of the nutrients in the hybrid paper mulberry feed by animals. The content of crude fiber and lignin in hybrid paper mulberry feed is high. Crude fiber is mainly composed of cellulose, hemicellulose and lignin. Monogastric animals are difficult to digest cellulose and hemicellulose, and lignin cannot be digested and utilized by all livestock and poultry. . Through the fermentation of Candida utilis, crude fiber can be degraded, its content can be reduced, and the utilization rate of feed digestion can be improved. Anti-nutritional factors such as crude fiber and lignin in hybrid paper mulberry feed affect the palatability of hybrid paper mulberry feed. Fermentation treatment of Candida utilis has a certain softening effect on lignin and plant fiber, which has a great effect on improving the palatability of feed. Great help. The viable count of Candida utilis in the fermented hybrid paper mulberry feed is ≥1 billion/g. As a probiotic, Candida utilis can regulate the microecological balance of the animal's gastrointestinal tract and enhance the body's immunity after entering the animal's digestive tract. , improve the feed conversion rate, promote animal growth, and improve the economic benefits of breeding.

5. Effects of fermented hybrid paper mulberry feed on growth performance of finishing pigs

1. Experimental animals and experimental design

Completely randomly selected 44 Du×Chang×Big ternary hybrid pigs that were healthy, basically the same age, and weighed about 30kg and were randomly divided into two groups. The control group and the experimental group were divided into 22 pigs in each group. Repeat for 11 pigs. The test is divided into 2 stages of 30-50kg and more than 50kg. The control group was fed the basal diet, and the experimental group was fed the basal diet supplemented with 10% fermented hybrid paper mulberry feed (30-50kg) and the basal diet supplemented with 15% fermented hybrid paper mulberry feed (above 50kg) according to different stages.

, Fermented hybrid paper mulberry feed

Fermented hybrid paper mulberry feed was prepared according to the method of Example 3.

, Feeding management and test records

The experiment was carried out in a pig farm of a family farm in Henan Province. Vaccination and feeding management are carried out according to the routine procedures of the pig farm. The pre-test period was 5 days, and the test period was until the commercial pigs were put out for slaughter. During the test period, the animals were allowed to eat and drink ad libitum. On the 1st, 40th and 120th day of the test, the live weight and food consumption of each group were weighed and recorded after fasting for 12 hours.

The effect of fermented hybrid paper mulberry feed on the growth performance of finishing pigs

The test results are shown in Table 2. It can be seen from Table 2 that the average daily feed intake of 30-50kg fattening pigs with 10% fermented hybrid paper mulberry feed in the basic diet is increased by 6.40% compared with the control group, and the average daily weight gain is higher than that of the control group. The group decreased by 6.70%, and the feed-to-weight ratio increased by 13.95% compared with the control group. When the basal diet was supplemented with 15% fermented hybrid paper mulberry feed, the average daily feed intake and average daily weight gain were 4.13% and 4.71% higher than those of the control group, respectively, and the feed weight was 0.66% lower than that of the control group. Therefore, the fermented hybrid paper mulberry feed has a certain effect on increasing the average daily feed intake and average daily weight gain of fattening pigs, but has no obvious effect on reducing the feed-to-weight ratio.

Table 2 Effects of fermented hybrid paper mulberry feed on growth performance of finishing pigs 30～50kg control group test group 50kg or more control group test group Initial weight (kg) 29.56 29.43 Initial weight (kg) 52.83 51.15 Final weight (kg) 52.83 51.15 Final weight (kg) 127.60 129.49 Average daily feed intake (g) 1250 1330 Average daily feed intake (g) 2830 2947 Average daily weight gain (g) 582 543 Average daily weight gain (g) 935 979 Material to weight ratio 2.15 2.45 Material to weight ratio 3.03 3.01

6. The effect of fermented hybrid paper mulberry feed on the performance of broilers

1. Experimental animals and experimental design

Using single factor randomization, 160 AA broilers were randomly divided into 2 groups with 80 chickens in each group, with 4 replicates and 20 chickens in each replicate. The control group was fed the basal diet, and the experimental group was fed the basal diet containing 5% fermented hybrid paper mulberry feed.

, Fermented hybrid paper mulberry feed

Fermented hybrid paper mulberry feed was prepared according to the method of Example 3.

, Feeding management and test records

The experiment was carried out in a broiler farm in Henan. Vaccination and feeding management were carried out according to the routine procedures of AA broilers. The rats were weighed on an empty stomach at 1, 14, 28, and 42 days of age, respectively. Fasting and water for 12 hours before weighing, and the 1-14-day-old, 15-28-day-old, 29-42-day-old and 1-42-day-old were calculated. The average daily feed intake of AA broilers at each stage was calculated using the average daily gain of each stage and the average daily gain of the whole period to calculate the feed-to-meat ratio.

The effect of fermented hybrid paper mulberry feed on the performance of broilers

The test results in Table 3 show that the test results of feeding 5% fermented hybrid paper mulberry feed are as follows: compared with the control group, the average daily feed intake of 1-14-day-old AA broilers is reduced by 4.57%, and the average daily weight gain is reduced by 10.45% , the ratio of feed to meat increased by 6.80%. Compared with the control group, the average daily feed intake of 15-28-day-old AA broilers decreased by 2.45%, the average daily gain decreased by 6.28%, and the feed-to-meat ratio increased by 3.98%. Compared with the control group, the average daily feed intake of 29-42-day-old AA broilers decreased by 1.21%, the average daily gain increased by 1.14%, and the feed-to-meat ratio decreased by 2.20%. Compared with the control group, the average daily feed intake of AA broilers aged 1-42 days decreased by 2.13%, the average daily gain decreased by 3.74%, and the feed-to-meat ratio increased by 1.48%. It can be seen that with the development of the digestive system of broilers, they gradually adapted to the feeding of fermented hybrid paper mulberry feed. The average daily feed intake at 29-42 days of age decreased, and the average daily weight gain increased. The ratio of feed to meat decreased, indicating that the utilization rate of fermented hybrid paper mulberry feed was significantly improved by AA broilers in the breeding stage. However, it has a certain negative impact on the production performance of AA broilers, such as average daily feed intake, average daily gain and feed-to-meat ratio.

Table 3 Effects of fermented hybrid paper mulberry feed on the performance of broilers

7. The effect of fermented hybrid paper mulberry feed on the growth performance of meat rabbits

1. Experimental animals and experimental design

Eighty 30-day-old weaned New Zealand meat rabbits with similar body weight, half male and female, healthy and well-developed, were randomly divided into 4 groups with 20 rabbits in each group, with 4 replicates and 5 rabbits in each replicate. Group I was the control group and was fed the basal diet. Groups II, III, and IV were the experimental groups. The basal diet of rabbits in the experimental group was supplemented with 10%, 20%, and 30% of fermented hybrid paper mulberry feed. amount of peanut seedling powder and peanut shell powder. The trial period is 65 days, of which the pre-trial period is 5 days and the positive trial period is 60 days.

, Fermented hybrid paper mulberry feed

Fermented hybrid paper mulberry feed was prepared according to the method of Example 3.

, Feeding management and test records

The experiment was carried out in a meat rabbit farm in Henan. The rabbits in the control group and the rabbits in the experimental group were all kept in single cages during the experiment, and the rearing conditions were consistent with the environmental conditions. Before the experiment, the cages and the environment were thoroughly washed and disinfected, and the vaccines were immunized according to the routine breeding management and immunization procedures of the rabbit farm. Feed twice a day, 8:00 in the morning and 18:00 in the afternoon. Adopt free feeding and free drinking water, keep the air quality of the rabbit house good, and disinfect the rabbit house once every 3 to 5 days. On the first day of the trial period and at 08:00 on the day of the end of the trial, fasting weighing was carried out in groups as a unit, the total feed intake during the trial period was counted, and the average daily weight gain, average daily feed intake and feed-to-weight ratio during the trial period were calculated. .

The effect of fermented hybrid paper mulberry feed on the growth performance of meat rabbits

The test results are shown in Table 4. It can be seen from Table 4 that adding 10%, 20% and 30% of the fermented hybrid paper mulberry feed to replace the same amount of peanut seedling powder and peanut shell powder in the diet increased the average daily weight gain of meat rabbits by 1.96. g, 4.30g, 4.48g, had no significant effect on the average daily feed intake, and the feed-to-weight ratio decreased by 0.26, 0.56, and 0.59, respectively, indicating that 10%, 20%, and 30% of fermented hybrid paper mulberry feed were added to the diet. The same amount of peanut seedling powder and peanut shell powder can significantly increase the average daily weight gain of meat rabbits, and reduce the feed-to-weight ratio of meat rabbits to varying degrees.

Table 4 Effects of fermented hybrid paper mulberry feed on growth performance of meat rabbits project Group I Group II Group III Group IV Initial weight (g) 844.12 843.53 840.00 839.78 Final weight (g) 2694.65 2809.23 2948.56 2959.43 Average daily weight gain (g) 30.84 32.76 35.14 35.32 Average daily feed intake (g) 140.75 140.81 140.68 140.17 Material to weight ratio 4.56 4.30 4.00 3.97

While carrying out the test on Example 3, the same test was also carried out on other examples, and the same and similar results were obtained, which will not be listed one by one here.

To sum up, the purpose of the present invention is to provide a microbial strain that can ferment hybrid paper mulberry feed raw materials and efficiently degrade various anti-nutritional factors such as cellulose and lignin, and utilize the strain to ferment and produce rich crude protein and peptides. The technical method of hybrid paper mulberry feed effectively solves the technical problems existing in the development and utilization of hybrid paper mulberry feed, opens up a new way of animal husbandry and breeding industry feed, promotes the development of animal husbandry, improves the economic benefits of breeding industry, and alleviates protein feed. Actively contribute to tight supply of raw materials and ensure food safety.

Claims (4)

1. A strain of Candida utilis UCY-11, classified and named as Candida utilis , the deposit number is CGMCC No. 19132, the deposit unit: General Microbiology Center of China Microorganism Culture Collection, address : No. 3, Yard 1, Beichen West Road, Chaoyang District, Beijing, preservation date: December 16, 2019. 2. The application of the Candida utilis strain UCY-11 of claim 1 in the preparation of fermented hybrid paper mulberry feed. 3. the application of Candida utilis strain UCY-11 described in claim 2 in the preparation of fermented hybrid paper mulberry feed, it is characterized in that, its application method comprises the following steps: (1) Preparation of seed liquid: The Candida utilis strain UCY-11 was cultured in the fermented seed liquid medium, and the fermented seed liquid was obtained by culturing it in a fermented seed Erlenmeyer flask. The speed is 10～15r/min; The fermented seed liquid medium is prepared by dissolving 20.0 g of glucose, 10.0 g of peptone and 5.0 g of yeast extract in 1 L of deionized water, and sterilized at 121° C. for 15 minutes; (2) Preparation of fermented hybrid paper mulberry medium: the medium is calculated by the following mass percentages: 65-75% of hybrid paper mulberry dry powder, 5-15% of corn flour, 4-6% of wheat bran, 4-6% of rice bran 6%, molasses 5-15% and inorganic salt 0.1-0.3%, the total amount is 100%, mix well, add water to make the mass water content reach 55-60%; Described inorganic salt is a kind of in ammonium salt, magnesium salt, sodium salt, potassium salt; (3) Preparation of fermented hybrid paper mulberry feed: inoculate the fermented seed liquid into the fermented hybrid paper mulberry medium according to the inoculation quality of 8-10%, put it into a triangular flask for fermentation and culture, and the loading amount is 30% of the volume of the triangular flask. ～50%, fermented for 48～72h under the condition of temperature of 32～36℃ to obtain fermented hybrid paper mulberry wet feed; (4) Drying: Dry the fermented hybrid paper mulberry wet feed under the condition of ≤60 °C to a mass water content of ≤12%, pulverize, and pass through a 40-60 mesh sieve, which is the finished product. 4. the application of Candida utilis strain UCY-11 according to claim 3 in the preparation of fermented hybrid paper mulberry feed, is characterized in that, its application method comprises the following steps: (1) Preparation of seed liquid: The Candida utilis strain UCY-11 was cultured in the fermented seed liquid medium, and the fermented seed liquid was obtained by culturing it in a fermented seed Erlenmeyer flask. 12r/min; (2) Preparation of fermented hybrid paper mulberry medium: the medium is calculated by the following mass percentages: 69% hybrid paper mulberry dry powder, 10% corn flour, 5.4% wheat bran, 5.4% rice bran, 10% molasses and inorganic Salt 0.2%, the total amount is 100%, mix evenly, add water to make the mass water content reach 55-60%; (3) Preparation of fermented hybrid paper mulberry feed: the fermented seed liquid is inoculated into the fermented hybrid paper mulberry medium according to the inoculation quality of 9%, and put into a triangular flask for fermentation culture, and the loading amount is 40% of the volume of the triangular flask, Fermentation for 60 hours at a temperature of 34°C to obtain wet feed of fermented hybrid paper mulberry; (4) Drying: Dry the fermented hybrid paper mulberry wet feed under the condition of ≤60 °C to a mass water content of ≤12%, pulverize it, and pass it through a 50-mesh sieve, which is the finished product.