Feed additive for preventing broiler necrotic enteritis, preparation method and application

Abstract

The invention discloses a feed additive for preventing broiler necrotic enteritis, a preparation method and application, and relates to the technical field of feed. Comprising the following raw materials in parts by weight: 15-30 parts of plant essential oil, 40-60 parts of deoxycholic acid, 10-20 parts of vitamin D310, 3-8 parts of protein zinc, 2-6 parts of saccharomyces cerevisiae and 1-5 parts of zeolite powder. The feed additive provided by the invention is clear in component, stable in property, convenient to operate and control, easy to realize industrial production, and convenient to popularize and apply. By adopting the feed additive provided by the invention, the integrity of the intestinal epithelial barrier can be improved, the intestinal flora structure can be improved, the immunity of the organism can be improved, and necrotic enteritis of broilers can be effectively prevented.

Description

Technical Field

[0001] The invention relates to the technical field of feed, and in particular to a feed additive for preventing necrotic enteritis in broiler chickens, a preparation method and application thereof. Background Art

[0002] Necrotic enteritis is an intestinal disease caused by infection with Clostridium perfringens, which seriously damages poultry production. Under certain conditions, Clostridium perfringens (type A or type G) in the intestines proliferates and secretes α-toxin and NetB toxin, leading to large-scale necrosis of the intestinal mucosa. Chickens suffer from depression, ruffled feathers, dehydration, bloody stools, decreased production performance, and other symptoms. The mortality rate is as high as 50%, which is extremely harmful. Both broilers and laying hens can be infected and fall ill, with broilers aged 2 to 5 weeks and laying hens over 5 weeks of age having more cases. According to statistics, the economic losses caused by necrotic enteritis to the global poultry industry are as high as US$6 billion per year.

[0003] For a long time, adding antibiotics to broiler feed has been a conventional way to control the occurrence of necrotic enteritis. Since July 1, 2020, my country has banned the addition of antibiotics to livestock and poultry feed. The incidence of necrotic enteritis in broiler chickens has increased year by year and has become an important infectious disease that damages broiler production. At present, in actual breeding processes, antibiotics such as lincomycin, penicillin, oxytetracycline, and virginiamycin are commonly used to treat necrotic enteritis in broiler chickens. The use of ionophore anticoccidial drugs can also help prevent the occurrence of necrotic enteritis in broiler chickens. However, the extensive use of antibiotics in the breeding process not only leads to bacterial resistance problems, but also leads to a large amount of antibiotic residues in meat products, which seriously threatens human food safety. Therefore, the development of safe and effective antibiotic alternatives to prevent or treat necrotic enteritis is a hot issue that urgently needs to be solved in broiler farming.

[0004] At present, there are some compound Chinese herbal medicines or Chinese herbal medicine extracts that can replace antibiotics and are used to prevent and treat poultry necrotic enteritis. For example, Chinese patents with publication numbers CN116327834A and CN115089638A disclose a compound Chinese herbal medicine or Chinese herbal medicine extract for preventing or treating chicken necrotic enteritis, both of which achieve the purpose of inhibiting the proliferation of Clostridium perfringens and preventing and treating chicken necrotic enteritis by adding compound Chinese herbal medicines or extracts to feed. However, since the bitterness of Chinese herbal medicines affects the palatability of feeds to a certain extent, and the active components and effective contents in Chinese herbal medicines and their extracts are affected by various factors such as the origin of Chinese herbal medicines and climate, the drug efficacy stability is poor. Summary of the invention

[0005] The present invention provides a feed additive, preparation method and application for preventing necrotic enteritis in broilers, aiming to solve the problems existing in the above-mentioned background technology. The feed additive provided by the present invention can effectively promote intestinal health, improve the integrity of the intestinal mucosal barrier, reduce intestinal inflammatory response, improve the structure of intestinal flora, improve the body's antioxidant capacity, and reduce the occurrence of necrotic enteritis in broilers.

[0006] In order to achieve the above technical objectives, the present invention mainly adopts the following technical solutions:

[0007] In a first aspect, the present invention discloses a feed additive for preventing necrotic enteritis in broilers, comprising the following raw materials in parts by weight: 15-30 parts of plant essential oil, 40-60 parts of deoxycholic acid, 10-20 parts of vitamin D3, 3-8 parts of protein zinc, 2-6 parts of brewer's yeast, and 1-5 parts of zeolite powder.

[0008] Among them, plant essential oils are secondary metabolites of aromatic plants, which have a wide range of physiological functions such as antibacterial, antiviral, anti-inflammatory, and antioxidant. The composition of natural plant essential oils is very complex, including terpenes, phenols, aldehydes, ketones, and esters. Among the many plant essential oil components, cinnamaldehyde and phenols have the highest antibacterial activity, such as carvacrol, thymol, and eugenol. Affected by factors such as plant origin, variety, growth environment, harvest time, extraction site, and extraction method, the active ingredients of natural plant essential oils often fluctuate greatly, resulting in unstable effects of natural plant essential oils. The stability of the effects of plant essential oil products can be effectively guaranteed by synthesizing pure products.

[0009] Deoxycholic acid is a free secondary bile acid, which is generated from primary bile acid by bile acid hydrolase and 7α-dehydroxylase. It has the activities of promoting bile secretion, promoting food digestion and absorption, and eliminating bile stasis. Clinical studies in recent years have shown that deoxycholic acid is also involved in the occurrence and development of a variety of chronic diseases, such as obesity, diabetes, colorectal cancer, enteritis, etc.

[0010] Vitamin D3 is metabolized into active forms in poultry, promoting the absorption of calcium and phosphorus in the small intestine, which is essential for the bone development of poultry. In addition, vitamin D3 has a wide range of regulatory effects on the immune system, including increasing the phagocytosis, differentiation and production of antimicrobial peptides by macrophages, reducing inflammatory responses, enhancing cell-mediated and antibody-mediated immune responses, and enhancing the body's antimicrobial defense capabilities.

[0011] As an essential trace element for poultry, zinc is an essential component or cofactor of more than 300 enzymes or functional proteins, and plays an important role in a variety of physiological processes, including nutrient metabolism, immune function, antioxidant function, reproductive ability and epigenetic processes. Protein zinc is a form of organic zinc, and the bioavailability of medium-chelated zinc in poultry is better than that of inorganic zinc.

[0012] Brewer's yeast is a probiotic that can regulate the structure of intestinal flora, promote intestinal health, and enhance the ability of intestinal cells to absorb nutrients.

[0013] In a preferred embodiment of the present invention, the raw materials are included in the following parts by weight: 20-30 parts of plant essential oil, 50-60 parts of deoxycholic acid, 10-15 parts of vitamin D3, 3-6 parts of protein zinc, 3-6 parts of brewer's yeast, and 1-4 parts of zeolite powder.

[0014] Furthermore, the plant essential oil comprises the following raw materials in parts by weight: 20-45 parts of cinnamaldehyde, 8-15 parts of carvacrol, 8-15 parts of thymol, 4-10 parts of eugenol, and 40-60 parts of silicon dioxide.

[0015] In a preferred embodiment of the present invention, the plant essential oil is prepared by the following method: cinnamaldehyde, carvacrol, thymol and eugenol are mixed evenly, and then loaded with silica nanoparticles to prepare microcapsule-encapsulated plant essential oil.

[0016] In a second aspect, the present invention discloses a method for preparing a feed additive for preventing necrotic enteritis in broilers as described in the first aspect, comprising weighing various raw material components of the feed additive and mixing them uniformly in proportion.

[0017] In a third aspect, the present invention discloses a use of the feed additive as described in the first aspect in preparing a feed for preventing necrotic enteritis in broiler chickens.

[0018] In a preferred embodiment of the present invention, the feed additive improves the production performance and immunity of broiler chickens, improves the intestinal epithelial barrier function, and promotes intestinal health.

[0019] In a preferred embodiment of the present invention, the feed additive reduces the intestinal damage score of broiler chickens, improves intestinal tissue morphology, improves the integrity of the intestinal epithelial barrier and the activity of intestinal maltase and sucrase, increases the height of the villi, reduces the depth of the crypts, increases the ratio of the villus height to the crypt depth, reduces the number of Clostridium perfringens in the ileum contents, and increases the levels of serum IgA and IgG in broiler chickens.

[0020] In a fourth aspect, the present invention discloses a feed for preventing necrotic enteritis in broiler chickens, comprising the feed additive as described in the first aspect.

[0021] In a preferred embodiment of the present invention, the feed additive is added to the basic feed at a ratio of 0.06-0.12%.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] (1) The feed additive provided by the present invention has clear components, stable properties, convenient operation and control, easy to realize industrial production, and convenient for promotion and application.

[0024] (2) The feed additive provided by the present invention can enhance the immunity of broilers, improve the intestinal tissue morphology of broilers, improve the intestinal flora structure, and effectively prevent necrotic enteritis in broilers caused by Clostridium perfringens infection. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is the intestinal injury score diagram for each group in Experimental Example 2;

[0026] Figure 2 This is the intestinal injury score diagram for each group in Experimental Example 3. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical scheme and advantages of the present application clearer, the present application is further described in detail below in conjunction with the examples. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application. The reagents not described separately in detail in the present application are all conventional reagents and can be obtained from commercial channels; the methods not described in detail are all conventional test methods and can be obtained from the prior art.

[0028] Example 1 Preparation of feed additive 1

[0029] Take 30 parts of cinnamaldehyde, 12 parts of carvacrol, 12 parts of thymol, and 6 parts of eugenol, mix them evenly, and then load them with 40 parts of mesoporous silica nanoparticles to prepare microcapsule-coated plant essential oil. Then take 15 parts of plant essential oil, 60 parts of deoxycholic acid, 10 parts of vitamin D3, 8 parts of protein zinc, 6 parts of brewer's yeast, and 1 part of zeolite powder, mix them evenly, and obtain feed additive 1.

[0030] Example 2 Preparation of feed additive 2

[0031] Take 26 parts of cinnamaldehyde, 10 parts of carvacrol, 10 parts of thymol, and 4 parts of eugenol, mix them evenly, and then load them with 50 parts of mesoporous silica nanoparticles to prepare microcapsule-coated plant essential oil. Then take 25 parts of plant essential oil, 50 parts of deoxycholic acid, 12 parts of vitamin D3, 5 parts of protein zinc, 5 parts of brewer's yeast, and 3 parts of zeolite powder, mix them evenly, and obtain feed additive 2.

[0032] Example 3 Preparation of feed additive 3

[0033] Take 20 parts of cinnamaldehyde, 8 parts of carvacrol, 8 parts of thymol, and 4 parts of eugenol, mix them evenly, and then load them with 60 parts of mesoporous silica nanoparticles to prepare microcapsule-coated plant essential oil. Take 30 parts of plant essential oil, 40 parts of deoxycholic acid, 20 parts of vitamin D3, 3 parts of protein zinc, 2 parts of brewer's yeast, and 5 parts of zeolite powder, mix them evenly, and obtain feed additive 3.

[0034] The following specifically examines the effect of the feed additive prepared in Example 2 on necrotic enteritis in broiler chickens.

[0035] Experimental Example 1: Investigating the effects of different doses of feed additives on broiler production performance

[0036] 240 one-day-old male Arbor Acres broiler chickens with the same body weight were randomly assigned to three treatments, each with 8 replicates and 10 chickens in each replicate. The control group did not add the additive of the present invention, while the experimental group 1 and the experimental group 2 added 600 mg and 800 mg of the additive of the present invention per kilogram of diet, respectively. Other conditions were the same, and the chickens were raised to 42 days of age to observe the effect of the additive on the growth performance of broilers. The results are shown in Table 1.

[0037] As shown in Table 1, adding the additive of this test example to the broiler diet does not affect the production performance of broilers at 0-42 days of age.

[0038] Table 1 Production performance of broiler chickens from 0 to 42 days of age

[0039] project Body weight gain (g) Feed intake (g) Material weight ratio Control group 2190 4117 1.88 Test Group 1 2215 4209 1.9 Test Group 2 2244 4196 1.87

[0040] Experimental Example 2: Investigating the preventive effects of different additives on necrotic enteritis in broiler chickens

[0041] 320 7-day-old male Cobb 500 broilers of uniform body weight were randomly assigned to 4 treatments, each with 8 replicates and 10 chickens in each replicate. They were control group, infection group, test group 1 and test group 2. The control group and infection group broilers were fed a wheat-soybean meal-fish meal type basal diet, and the test group 1 was supplemented with 250 mg of the plant essential oil in Example 2 per kilogram of basal diet, and the test group 2 was supplemented with 800 mg of the feed additive in Example 2 per kilogram of basal diet. The basal diet formula is shown in Table 2.

[0042] Table 2 Basic diet formula and nutritional level of broiler chickens

[0043]

[0044] Except for the control group, all broiler chickens in the treatment groups were gavaged with 25 times the dose of mixed coccidia vaccine (canonical TM Four-valent) and fed with fresh culture solution of Clostridium perfringens type G for three consecutive days at 16-18 days of age (108 cfu / bird / time), and gavage-fed twice a day. The test site was the Jinshui Test Base of the Hubei Academy of Agricultural Sciences. The chickens were kept in multi-layer cages in the same chicken house, and they were allowed to eat and drink freely. They were slaughtered on the 26th day of age, scored according to the intestinal damage, and intestinal samples were collected to detect intestinal morphology and function. In addition, the ileum contents were collected for plate culture to determine the number of viable bacteria in the intestinal contents.

[0045] Intestinal injury score Figure 1 It can be seen that infection significantly increased the intestinal lesion score of broiler chickens, and the intestinal lesion score was significantly reduced in groups 1 and 2. Compared with group 1, group 2 had a significantly lower intestinal lesion score.

[0046] Intestinal brush border hydrolases (such as disaccharidases) play an important role in the digestion of intestinal nutrients and intestinal health. Maltose, sucrose, etc. can only be absorbed and utilized by the intestines when they are hydrolyzed into monosaccharides under the action of disaccharidases. As can be seen from Table 3, infection significantly reduced the activities of maltase and sucrase in the jejunum of broiler chickens. Compared with the infection group, test group 1 did not affect the activity of intestinal disaccharidases, while test group 2 significantly increased the activities of intestinal maltase and sucrase.

[0047] Intestinal tissue morphology is an important indicator of intestinal health. As shown in Table 4, infection significantly reduced the height of villus in the jejunum of broiler chickens, increased the depth of crypts, and reduced the ratio of villus height to crypt depth. Compared with the infection group, test group 1 did not affect the intestinal tissue morphology, while test group 2 significantly increased the height of villus, reduced the depth of crypts, and increased the ratio of villus height to crypt depth.

[0048] According to Table 5, infection significantly increased the number of Escherichia coli and Clostridium perfringens in the ileal contents. Compared with the infection group and the test 1 group, the test 2 group significantly decreased the number of Clostridium perfringens in the ileal contents.

[0049] Table 3 Disaccharidase activity of jejunal mucosa of broiler chickens

[0050] project Maltase activity (U / mgprot) Sucrase activity (U / mgprot) Control group <![CDATA[331.8±11.3 ab ]]> <![CDATA[61.3±2.4 a ]]> Infection group <![CDATA[251.0±9.4 c ]]> <![CDATA[28.8±4.3 b ]]> Test Group 1 <![CDATA[264.4±23.5 bc ]]> <![CDATA[35.4±4.1 b ]]> Test Group 2 <![CDATA[378.9±18.1 a ]]> <![CDATA[62.7±2.7 a ]]>

[0051] Table 4 Morphology of jejunum in broiler chickens

[0052] project Villus height (μm) Crypt depth (μm) Villus height to crypt depth ratio Control group <![CDATA[1015±27 a ]]> <![CDATA[133±4 b ]]> <![CDATA[7.6±0.2 a ]]> Infection group <![CDATA[693±25 b ]]> <![CDATA[169±3 a ]]> <![CDATA[4.1±0.1 b ]]> Test Group 1 <![CDATA[720±29 b ]]> <![CDATA[152±6 ab ]]> <![CDATA[4.8±0.1 b ]]> Test Group 2 <![CDATA[975±33 a ]]> <![CDATA[142±2 b ]]> <![CDATA[6.9±0.2 a ]]>

[0053] Table 5 Bacterial counts in ileum of broiler chickens (log 10 cfu / g)

[0054] project Escherichia coli Lactobacilli Clostridium perfringens Control group <![CDATA[7.25±0.18 b ]]> 8.09±0.10 <![CDATA[0.50±0.08 c ]]> Infection group <![CDATA[8.99±0.21 a ]]> 8.04±0.09 <![CDATA[5.62±0.12 a ]]> Test Group 1 <![CDATA[8.29±0.22 ab ]]> 8.15±0.07 <![CDATA[5.27±0.10 a ]]> Test Group 2 <![CDATA[8.32±0.24 ab ]]> 8.21±0.12 <![CDATA[2.33±0.13 b ]]>

[0055] Experimental Example 3: Investigating the intestinal protective effects of different additives on broiler chickens infected with Clostridium perfringens

[0056] 144 one-day-old male Arbor Acres broiler chickens with the same body weight were randomly assigned to three treatments, each with six replicates and eight chickens in each replicate. They were a control group, an infection group, and a test group. The control group and the infection group broiler chickens were fed a wheat-soybean meal type basal diet, and the test group was supplemented with 800 mg of the feed additive of Example 2 per kilogram of the basal diet. The basal diet formula is shown in Table 6.

[0057] Table 6 Basic diet formula and nutritional level of broiler chickens

[0058]

[0059]

[0060] From the 14th to the 20th day of age, broilers in the infection group and the experimental group were orally inoculated with 1 mL (about 1×10 8 cfu / mL); the control group was gavaged with 1 mL of sterile broth every day. The test site was the Jinshui Experimental Base of Hubei Academy of Agricultural Sciences. The chickens were raised in multi-layer cages in the same chicken house, and they were free to eat and drink. The production performance was counted in replicates. The broilers were raised until the 21st day of age and slaughtered, and the scores were given according to the intestinal damage. Blood samples were collected and serum was separated to detect the antibody level in the serum.

[0061] according to Figure 2 It can be seen that infection significantly increased the intestinal lesion score of broilers, while the intestinal lesion score of the test group decreased significantly. As shown in Table 7, the body weight gain of broilers in the infection group was significantly reduced, and the feed-to-weight ratio was significantly increased. Compared with the infection group, the test group significantly increased the body weight gain of broilers at 21 days of age and improved the feed-to-weight ratio. According to Table 8, compared with the infection group, the test group significantly increased the levels of serum IgA and IgG in broilers.

[0062] Table 7 Production performance of broiler chickens from 0 to 21 days of age

[0063] project Body weight gain (g) Feed intake (g) Material weight ratio Control group <![CDATA[781±6 a ]]> 1069±8 <![CDATA[1.37±0.01 b ]]> Infection group <![CDATA[650±5 c ]]> 988±10 <![CDATA[1.52±0.01 a ]]> Experimental Group <![CDATA[728±8 b ]]> 1013±10 <![CDATA[1.39±0.02 b ]]>

[0064] Table 8 Immune indicators of broiler chickens

[0065]

[0066]

[0067] The above specific implementation cases of the present invention are described in detail, but they are only examples, and the present invention is not limited to the specific implementation cases described above. For those skilled in the art, any equivalent modification and substitution of the present invention are also within the scope of the present invention. Therefore, the equalization and modification made without departing from the spirit and scope of the present invention should be included in the scope of the present invention.

Claims

1. A feed additive for preventing necrotic enteritis in broiler chickens, characterized in that: The invention comprises the following raw materials in parts by weight: 15-30 parts of plant essential oil, 40-60 parts of deoxycholic acid, 10-20 parts of vitamin D3, 3-8 parts of protein zinc, 2-6 parts of brewer's yeast and 1-5 parts of zeolite powder.

2. The feed additive for preventing necrotic enteritis in broiler chickens according to claim 1, characterized in that: The invention comprises the following raw materials in parts by weight: 20-30 parts of plant essential oil, 50-60 parts of deoxycholic acid, 10-15 parts of vitamin D3, 3-6 parts of protein zinc, 3-6 parts of brewer's yeast and 1-4 parts of zeolite powder.

3. The feed additive for preventing necrotic enteritis in broiler chickens according to any one of claims 1 or 2, characterized in that: The plant essential oil comprises the following raw materials in parts by weight: 20-45 parts of cinnamaldehyde, 8-15 parts of carvacrol, 8-15 parts of thymol, 4-10 parts of eugenol and 40-60 parts of silicon dioxide.

4. The feed additive for preventing necrotic enteritis in broiler chickens according to claim 3, characterized in that: The plant essential oil is prepared by the following method: cinnamaldehyde, carvacrol, thymol and eugenol are mixed evenly, and then loaded with silicon dioxide nanoparticles to prepare microcapsule-encapsulated plant essential oil.

5. A method for preparing a feed additive for preventing necrotic enteritis in broilers as claimed in claim 1, characterized in that: Weigh the raw material components of the feed additive and mix them evenly according to the proportion.

6. Use of the feed additive according to claim 1 in preparing feed for preventing necrotic enteritis in broiler chickens.

7. The use according to claim 6, characterized in that: The feed additive improves the production performance and immunity of broiler chickens, improves the intestinal epithelial barrier function, and promotes intestinal health.

8. The use according to claim 7, characterized in that: The feed additive reduces the intestinal damage score of broiler chickens, improves the intestinal tissue morphology, improves the integrity of the intestinal epithelial barrier and the activities of intestinal maltase and sucrase, increases the height of the villi, reduces the depth of the crypts, increases the ratio of the height of the villi to the depth of the crypts, reduces the number of Clostridium perfringens in the ileum content, and increases the levels of serum IgA and IgG in broiler chickens.

9. A feed for preventing necrotic enteritis in broiler chickens, characterized in that: Comprising the feed additive as claimed in claim 1.

10. The feed for preventing necrotic enteritis in broiler chickens according to claim 9, characterized in that: The feed additive is added to the basic feed at a ratio of 0.06-0.12%.

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