Feed additive for replacing antibiotics to treat chicken necrotic enteritis and application of feed additive
By using chestnut tannin extract as a feed additive, the problem of antibiotic dependence in the treatment of necrotizing enteritis in broilers has been solved, resulting in improvements in broiler production performance, intestinal morphology, and immune function, and providing a safe and efficient antibiotic alternative.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- QINGDAO AGRI UNIV
- Filing Date
- 2026-02-07
- Publication Date
- 2026-04-10
- Estimated Expiration
- Not applicable · inactive patent
AI Technical Summary
In existing technologies, the treatment of necrotizing enteritis in broilers relies too heavily on antibiotics, leading to bacterial resistance and drug residues, which affect food safety, and there is a lack of effective natural alternatives.
Chestnut tannin extract was used as a feed additive to improve the production performance, gut health and immune function of broilers, thus replacing antibiotics in the treatment of necrotizing enteritis.
Chestnut tannin extract significantly improved the production performance of broilers, improved intestinal morphology and immune function, and alleviated intestinal inflammatory damage, demonstrating good therapeutic effects.
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Abstract
Description
TECHNICAL FIELD
[0001] The present application belongs to the technical field of feed, and particularly relates to a feed additive for replacing antibiotic treatment of chicken necrotic enteritis and application thereof. BACKGROUND
[0002] Necrotic enteritis is a bacterial disease affecting the intestinal tract of poultry, mainly caused by Clostridium perfringens, and often associated with coccidiosis and fish meal, etc. Clostridium perfringens produces necrotic enteritis toxin beta, which leads to reduced nutrient utilization, intestinal microbiota imbalance and intestinal barrier damage, thereby causing intestinal inflammation damage in poultry. Necrotic enteritis in broilers usually occurs in acute clinical and chronic subclinical forms. The clinical form will cause diarrhea and high mortality, while the subclinical form is characterized by chronic damage to the intestinal tract and decline in production performance. With the development of intensive farming, over-reliance on antibiotic treatment of necrotic enteritis in poultry production has led to continuous increase in bacterial resistance and drug residues in products, thereby causing decreased disease resistance in poultry and food safety problems. Therefore, seeking feasible natural alternatives has attracted widespread attention.
[0003] Tannins are divided into condensed tannins and hydrolysable tannins according to their chemical structure. Chestnut tannin is a natural polyphenolic compound extracted from chestnut trees, mainly composed of tannin and gallotannin, belonging to the category of hydrolysable tannins, and has functions of anti-inflammatory, antioxidant, antibacterial and immune regulation. At the same time, due to the raw materials from chestnut trees of different ages and parts, the tannin molecular structure is diverse, can combine with a variety of proteins, and is more easily hydrolyzed and absorbed by the gastrointestinal tract to exert biological activity, thereby protecting the intestinal mucosa from damage. In addition, compared with other tannins such as gallnut tannin, the market price of chestnut tannin is more advantageous, and in recent years it has been widely used in the prevention and treatment of animal clinical diseases. In summary, chestnut tannin provides a new intervention target for nutritional regulation of necrotic enteritis in broilers, and lays a solid theoretical foundation for the development of safe and efficient antibiotic substitutes, which has far-reaching significance and great value for promoting the green and healthy development of the poultry industry. SUMMARY
[0004] In view of the deficiencies of the prior art, the purpose of the present application is to provide a feed additive for treating necrotic enteritis in broilers and application thereof.
[0005] In order to achieve the above technical purpose, the technical scheme adopted by the present application is: a feed additive for preventing and controlling necrotic enteritis in broilers, wherein the active ingredient of the feed additive is chestnut tannin extract.
[0006] It should be noted that the effective component of the feed additive of the present application is tannin extract from chestnut tree, and the chestnut tannin extract prepared by the present application is a brown powder, wherein the content of hydrolyzed tannin is 76.5% of dry matter. It can improve the production performance and intestinal health of broilers with necrotic enteritis, and has a therapeutic effect on broilers with necrotic enteritis.
[0007] Secondly, the present application also provides a broiler feed comprising a basic diet, in addition to which the feed also comprises the above-mentioned feed additive. Further preferably, the additive amount of the feed additive in the feed is 500-1000 mg / kg.
[0008] Thirdly, the present application also provides a preparation method of a feed additive, which comprises the following steps: taking the bark, wood or / and cup of chestnut tree, drying and crushing, and then performing ultrasonic extraction or hot reflux extraction for 1-4 times with a solvent, filtering, concentrating and drying to obtain chestnut tannin extract; the solvent is water or an ethanol aqueous solution.
[0009] Further preferably, the preparation method of the feed additive as described above, wherein the concentration of the ethanol aqueous solution is 30%-60% (v / v).
[0010] Further preferably, the preparation method of the feed additive as described above, wherein the solid-liquid mass ratio of ultrasonic extraction or hot reflux extraction is 1: (6-20).
[0011] Still further preferably, the preparation method of the feed additive as described above, wherein the solid-liquid mass ratio of ultrasonic extraction or hot reflux extraction is 1: (8-12).
[0012] Still further preferably, the preparation method of the feed additive as described above, wherein the temperature of hot reflux extraction is 55-65℃.
[0013] Still further preferably, the preparation method of the feed additive as described above, wherein the time of hot reflux extraction is 1-4 hours.
[0014] Finally, the present application also provides the use of chestnut tannin pure product or chestnut tannin extract in the preparation of a feed additive for preventing and controlling necrotic enteritis of broilers.
[0015] Compared with the prior art, the present application has the following beneficial effects:
[0016] (1) The chestnut tannin extract can improve the production performance, intestinal morphology and immune function of broilers with necrotic enteritis, thereby relieving intestinal inflammatory damage, and further used as a feed additive for replacing antibiotics to treat chicken necrotic enteritis.
[0017] (2) The chestnut tannin extract can improve the production performance of broilers with necrotic enteritis to a certain extent, and can improve the intestinal morphology and immune function of broilers with necrotic enteritis. This shows that the chestnut tannin extract can replace antibiotics and has a good treatment effect on the intestinal inflammation of broilers caused by Clostridium perfringens and coccidia. DETAILED DESCRIPTION
[0018] The present application will be further illustrated by the following test examples. It should be understood that the following test examples are only used to illustrate the technical solutions and technical effects of the present application, and are not a limitation on the protection scope of the present application. Simple improvements of the method under the premise of the general concept all belong to the scope of protection of the present application.
[0019] The experimental methods in the following examples are all conventional methods unless otherwise specified. The materials, reagents, etc. used in the following examples can be obtained from commercial channels unless otherwise specified.
[0020] Example 1, preparation of chestnut tannin extract
[0021] Dry European chestnut wood was crushed through a 20-mesh sieve. 1 kg of raw material was weighed, 10 liters of 50% (v / v) ethanol aqueous solution was added, and hot reflux extraction was carried out at 60°C for 2 hours. Filtration was performed, and the filtrate was collected. The filter residue was repeatedly extracted once, and the two filtrates were combined. The filtrate was concentrated to a paste at 50°C under reduced pressure, and then spray dried to obtain about 120 grams of chestnut tannin extract in the form of brownish yellow powder. The content of hydrolyzed tannin was determined by the Folin-phenol method to be 76.5% of the dry matter, which was used as the test substance for the animal experiment of Example 2.
[0022] Example 2, test of the effect of chestnut tannin on broiler necrotic enteritis
[0023] 1 Test method
[0024] 240 healthy male Cobb 500 broilers (44.54±0.51g) at 1 day of age were randomly divided into 4 treatment groups. Each treatment group consisted of 6 cages (length 115 cm x width 95 cm x height 65 cm), with 10 broilers in each cage. The broilers were raised for 35 days.
[0025] The four groups included a control group (basic diet), a B challenge group (basic diet + 4x10 8 CFU / mL of Clostridium perfringens), a C challenge + low dose of chestnut tannin group (basic diet + chestnut tannin 500 mg / kg added to the diet + 4x10 8 CFU / mL of Clostridium perfringens), and a D challenge + high dose of chestnut tannin group (basic diet + chestnut tannin 1000 mg / kg added to the diet + 4x108 CFU / mL Clostridium perfringens). On day 14, the challenged group, the challenged + chestnut tannin low dose group and the challenged + chestnut tannin high dose group of broilers were orally administered with 1 mL containing 4 species of Eimeria at 1 x 10 5 CFU / mL Clostridium perfringens). On day 14, the challenged group, the challenged + chestnut tannin low dose group and the challenged + chestnut tannin high dose group of broilers were orally administered with 1 mL containing 4 species of Eimeria at 1 x 10 8 CFU / mL Clostridium perfringens). On day 14, the challenged group, the challenged + chestnut tannin low dose group and the challenged + chestnut tannin high dose group of broilers were orally administered with 1 mL containing 4 species of Eimeria at 1 x 10
[0026] On day 28 and 35, one broiler with the weight close to the average weight of the group was selected from each cage. After 12 hours of fasting, blood was collected from the subclavian vein, and serum was separated by centrifugation and stored at -20 °C for the determination of indicators. Immediately after exsanguination by jugular vein, the abdominal cavity was opened, the jejunum and ileum were removed, washed with sterile saline, and then fixed with 4% paraformaldehyde for histomorphometric analysis. Subsequently, the remaining jejunum and ileum segments were cut longitudinally, and the intestinal mucosa was scraped for immune function analysis and stored in a refrigerator at -80 °C.
[0027] 2. Determination indicators
[0028] 2.1 Production performance
[0029] The initial body weight of each replicate of the chicks was weighed before the start of the experiment. The fasting weight of the chickens was weighed on day 14 and 35, and the amount of feed provided and the amount of feed remaining were accurately recorded for each replicate during the experiment. The average daily gain (ADG) and average daily feed intake (ADFI) and the feed to gain ratio (F / G) were calculated based on the data.
[0030] 2.2 Intestinal morphology
[0031] The fixed jejunum and ileum segments were dehydrated, transparentized, and embedded to make paraffin sections, which were stained with hematoxylin and eosin and imaged under an optical microscope. Image analysis software was used to measure the villus height (VH) and crypt depth (CD) and calculate the villus to crypt ratio (V / C). Three replicates were set for each sample.
[0032] 2.3 Immune function
[0033] 0.1 g of jejunum mucosa was homogenized in 0.9 mL of saline, and the supernatant was obtained by centrifugation at 3000 rpm for 10 minutes. The concentrations of IL-1β, IL-6, IL-10, TNF-α, and IFN-γ in the jejunum mucosa were determined using ELISA kits according to the manufacturer's requirements, and the total protein concentration in the jejunum mucosa was determined using a protein detection kit. The concentrations of IL-1β, IL-6, IL-10, TNF-α, and IFN-γ were expressed as the content per milligram of mucosal protein.
[0034] 3 Experimental results
[0035] 3.1 Production performance
[0036] Table 1: Production performance of broilers in each group
[0037]
[0038] Note: Different superscript lowercase letters in the same column indicate significant difference (P < 0.05), and the same superscript letter or no superscript letter indicates no significant difference (P > 0.05).
[0039] From the experimental statistical results in Table 1, before infection with necrotic enteritis (1-14 d), the production performance indicators of broilers in each group had no significant difference (P > 0.05). After infection with necrotic enteritis (14-35 d), compared with the control group, the challenge group significantly reduced ADG (P < 0.05) and significantly increased F / G (P < 0.05); compared with the challenge group, the ADG of the low-dose chestnut tannin group and the high-dose chestnut tannin group was significantly increased (P < 0.05), and the F / G was significantly decreased (P < 0.05). During the whole test period (1-35 d), infection with necrotic enteritis significantly reduced ADG (P < 0.05) and significantly increased F / G (P < 0.05), while the ADG of the low-dose chestnut tannin group and the high-dose chestnut tannin group was significantly increased (P < 0.05) and the F / G was significantly decreased (P < 0.05) based on the infection with necrotic enteritis.
[0040] 3.2 Intestinal morphology
[0041] Table 2: Intestinal morphology of broilers in each group
[0042]
[0043] Note: Different superscript lowercase letters in the same column indicate significant difference (P < 0.05), and the same superscript letter or no superscript letter indicates no significant difference (P > 0.05).
[0044] From the experimental statistical results in Table 2, infection with necrotic enteritis changed the intestinal morphology of broilers. Specifically, at 28 days of age, compared with the control group, the CD of the jejunum and ileum of the challenge group was significantly increased (P < 0.05), while the VH and V / C of the jejunum and ileum were significantly decreased (P < 0.05). On the basis of infection with necrotic enteritis, the addition of chestnut tannin improved the VH, CD, and V / C of the jejunum and ileum (P < 0.05), but the VH and V / C of the jejunum and ileum of the low-dose chestnut tannin group were excluded. At 35 days of age, compared with the challenge group, the control group, the low-dose chestnut tannin group, and the high-dose chestnut tannin group significantly increased the VH and V / of the jejunum and ileum (P < 0.05) and significantly decreased the CD (P < 0.05).
[0045] 3.3 Immune function
[0046] Table 3: Inflammatory cytokine concentrations in each group of broilers
[0047]
[0048] Note: The same row with different lowercase letters indicates a significant difference (P < 0.05), and the same row with the same letter or no letter indicates no significant difference (P > 0.05).
[0049] From the experimental statistical results in Table 3, at 28 days of age, the infection of necrotic enteritis significantly increased the concentrations of IL-1β, IL-6, TNF-α, and IFN-γ in the jejunum of broilers (P < 0.05) and significantly reduced the concentration of IL-10 (P < 0.05). Compared with the challenge group, the high-dose chestnut tannin group significantly reduced the concentrations of IL-6, TNF-α, and IFN-γ (P < 0.05). At 35 days of age, compared with the challenge group, the IL-1β, IL-6, TNF-α, and IFN-γ concentrations in the control group and the high-dose chestnut tannin group were significantly reduced (P < 0.05). In addition, the IL-10 concentration in the high-dose chestnut tannin group was significantly increased (P < 0.05). At 28 and 35 days of age, no statistically significant changes were observed in the concentrations of IL-1β, IL-6, IL-10, TNF-α, and IFN-γ between the low-dose chestnut tannin group and the high-dose chestnut tannin group (P > 0.05).
[0050] 4. Conclusion
[0051] (1) The addition of chestnut tannin to the diet can improve the production performance of broilers with necrotic enteritis to some extent. The high-dose compound Chinese herbal medicine group has the best effect, with no significant difference from the normal control group.
[0052] (2) The addition of chestnut tannin to the diet can significantly improve the intestinal morphology of the jejunum of broilers with necrotic enteritis, which is beneficial to maintaining the normal nutrient digestion and absorption function of the intestine.
[0053] (3) The addition of chestnut tannin to the diet can significantly reduce the concentration of pro-inflammatory cytokines in the jejunum of broilers with necrotic enteritis and significantly increase the level of anti-inflammatory cytokines, which is beneficial to alleviate intestinal inflammation damage.
[0054] In summary, the addition of 1000 mg / kg chestnut tannin to the diet has a better effect on improving the production performance, intestinal morphology, and immune function of broilers with necrotic enteritis.
Claims
1. A feed additive for the prevention and control of necrotic enteritis in broilers, characterized in that, The active ingredient in this feed additive is chestnut tannin extract.
2. A broiler feed, comprising a basal diet, characterized in that, The feed also includes the feed additives as described in claim 1.
3. The broiler feed according to claim 2, characterized in that, The feed additive is added to the feed at a dosage of 500-1000 mg / kg.
4. A method for preparing a feed additive, characterized in that, The method includes the following steps: taking the bark, wood, and / or cupules of chestnut trees, drying and pulverizing them, and then performing ultrasonic extraction or hot reflux extraction with a solvent 1-4 times. After filtration, the extract is concentrated and dried to obtain chestnut tannin extract; the solvent is water or an aqueous ethanol solution.
5. The method for preparing the feed additive according to claim 4, characterized in that, The concentration of the ethanol aqueous solution is 30%-60% (v / v).
6. The method for preparing the feed additive according to claim 4, characterized in that, The mass ratio of the material to the liquid in the ultrasonic extraction or hot reflux extraction is 1:(6-20).
7. The method for preparing the feed additive according to claim 6, characterized in that, The mass ratio of material to liquid in the ultrasonic extraction or hot reflux extraction is 1:(8-12).
8. The method for preparing the feed additive according to claim 4, characterized in that, The temperature for the hot reflux extraction is 55-65℃.
9. The method for preparing the feed additive according to claim 4, characterized in that, The hot reflux extraction time is 1-4 hours.
10. Application of chestnut wood tannin extract in the preparation of feed additives for the prevention and control of necrotizing enteritis in broilers caused by Clostridium perfringens and coccidia.