A feed of myrobalan tannic acid for improving diarrhea, nitrogen utilization and immunity of a calf and a preparation method thereof

Abstract

The present application belongs to the technical field of feed preparation, and relates to a sumac tannic acid feed for improving diarrhea, nitrogen utilization and immunity of a calf and a preparation method thereof, specifically comprising preparation of sumac tannic acid and sumac-willow branch extract, and mixing with pretreated base material, puffed corn, mineral salt and probiotics to obtain the sumac tannic acid feed; through natural antibacterial components such as tannic acid and gallic acid in the sumac extract, multi-stage extraction and fermentation process and other means, the present application realizes synergistic effect of probiotics-antioxidants, achieves a technical breakthrough in replacing antibiotics, improving nitrogen utilization rate and enhancing immunity, and the core advantage thereof compared with the prior art lies in efficient utilization of natural components, by-product recycling and multi-target function synergy, thereby providing an economic and sustainable solution for healthy breeding of a calf.

Description

Technical Field

[0001] This invention belongs to the field of feed preparation technology, specifically relating to a gallnut tannin feed that improves calf diarrhea, nitrogen utilization, and immunity, and its preparation method. Background Technology

[0002] With the widespread ban on antibiotics in feed, effectively alleviating calf diarrhea has become an urgent technical problem. Due to its high morbidity, high mortality, stunted growth, and high treatment costs, calf diarrhea is one of the most serious diseases affecting calf health, severely impacting later growth, development, and production performance. It not only slows growth, reduces immunity, and delays calving, but is also the most common cause of death during the first 30 days of life, accounting for 57% of weaned calf deaths. Calf diarrhea not only affects its own growth and development but also seriously impacts herd renewal and the sustainable development of the dairy industry.

[0003] Traditional methods of treating diarrhea often involve adding antibiotics (such as tetracycline and bacitracin) to calf feed. However, long-term use of antibiotics can lead to the development of drug-resistant strains, and drug residues may harm human health through the food chain. In recent years, global policies to ban antibiotics in feed have become increasingly stringent, making the method of adding antibiotics to feed no longer applicable.

[0004] Probiotics are commonly used in existing feeds to control diarrhea, but the effects of single strains are limited, making it difficult to exert antibacterial and diarrhea-controlling effects. Calves have a weak ability to digest protein in feed, and existing feeds do not fully incorporate enzymatic hydrolysis and fermentation technologies, resulting in high nitrogen excretion, which wastes resources and pollutes the environment. Existing feeds lack targeted immune-enhancing components and rely heavily on vitamin or trace element supplementation, but they do not activate the intestinal immune barrier through synergistic effects.

[0005] Therefore, providing a feed that can replace traditional antibiotics and improve calf nitrogen utilization and immunity has become an urgent problem to be solved. Summary of the Invention

[0006] To address the aforementioned issues, this invention adds tannic acid to feed to improve the intestinal function of calves. Tannic acid can increase the abundance of beneficial bacteria, reduce the abundance of potentially pathogenic bacteria, and enhance antioxidant capacity. However, different types of tannic acid have different chemical structures, and their abilities to reduce diarrhea and regulate intestinal function also vary.

[0007] The tannins used in this invention are derived from the traditional Chinese medicine gallnut, which has the highest tannin content among plants (60-80%). Therefore, this invention provides a gallnut tannin feed that improves diarrhea, nitrogen utilization, and immunity in calves.

[0008] The specific preparation method includes the following steps:

[0009] Step 1: Dry the gallnut and willow branches at 40-50℃ until the moisture content is ≤5%, and pulverize them into 40-50 mesh powder. Mix the gallnut powder with an organic acid solution with pH 4.5-5.5 at a solid-liquid mass ratio of 1:8, and stir at 40-50℃ and 120-150 rpm for 2-2.5 hours to obtain an activated solution.

[0010] Add extractant one to the activation solution, reflux at 70-75℃ for 1.5-2 hours, filter through a 180-220 mesh screen to obtain primary filtrate and primary residue. Add extractant one to the primary residue, ultrasonically extract at 50-60℃ and 40-50kHz for 40-50 minutes, filter through a 180-220 mesh screen to obtain secondary filtrate and secondary residue. Combine the primary and secondary filtrates, dry at (-30)℃-(-20)℃ and 10-20Pa to obtain gallnut tannic acid.

[0011] The secondary filter residue, willow twig powder and extractant were mixed and refluxed at 70-75℃ for 2-2.5 hours. After filtration through a 180-220 mesh filter, a tertiary filtrate and a tertiary filter residue were obtained. The tertiary filtrate was dried at 25-35℃ to obtain the gallnut-willow twig extract.

[0012] Preferably, the organic acid solution is one or more of acetic acid solution, citric acid solution and lactic acid solution.

[0013] Preferably, the volume ratio of the activating solution to the first extractant is 1:1, and the mass ratio of the primary filter residue to the first extractant is 1:1. Most preferably, the first extractant is anhydrous ethanol.

[0014] Preferably, the mass ratio of the secondary filter residue, willow twig powder, and extractant two is 2:1:4. Most preferably, the extractant two is ethanol and ethyl acetate in a mass ratio of 2:1.

[0015] Step two: Grind the corn into a 20-30 mesh powder, then put it into an extrusion device for extrusion.

[0016] First stage: 115-125℃, 250-280rpm, moisture content 15-18%.

[0017] Second stage: 95-105℃, 300-320rpm, 0.1-0.2MPa water vapor.

[0018] Third stage: 75-85℃, 230-250rpm, (-0.1)-(-0.08)MPa dehydration until moisture content ≤7%, to obtain puffed corn.

[0019] Step 3: Mix the forage, soybean meal, wheat bran, and tertiary filter residue in a mass ratio of 10:7:3:4 and pulverize to 20-30 mesh to obtain the base material. Add compound microbial agent to the base material, and then adjust the moisture content to 60-70% with enzymatic hydrolysate. Ferment at 35-40℃, 50-60% humidity, and 10-12% oxygen concentration for 12-14 hours, turning it over every 1.5-2 hours. Then, statically ferment at 45-50℃, 55-65% humidity, and 12-15% carbon dioxide concentration for 24-26 hours. Then, mature at 55-60℃ and 25-30% humidity for 12-14 hours. After fermentation, inactivate at 90-95℃ for 15-20 minutes to obtain the pretreated base material.

[0020] Preferably, the mass ratio of the base material to the compound microbial agent is 50:1.

[0021] Preferably, the compound microbial agent is an EM microbial agent.

[0022] Preferably, the enzymatic hydrolysate contains 1800-2200 U / g of cellulase, 4800-5200 U / g of xylanase, and 3800-4200 U / g of protease.

[0023] Step 4: Mix the pretreated base material, puffed corn, gallnut tannic acid, gallnut-willow branch extract, mineral salts and probiotics in a mass ratio of (60-65):(30-35):(3-5):(10-12):(1-2):(0.1-0.2) and granulate the mixture. The particle size is 3-5 mm and the moisture content of the particles is ≤8%, thus obtaining gallnut tannic acid feed.

[0024] Preferably, the mineral salt comprises sodium chloride, calcium hydrogen phosphate, and magnesium sulfate in a mass ratio of 3:1:2.

[0025] Preferably, the probiotics include lactic acid bacteria and yeast in a mass ratio of 3:1.

[0026] The present invention has the following advantages:

[0027] (1) This invention uses natural antibacterial components (tannic acid) to replace antibiotics. Tannic acid has strong astringent properties, which can reduce intestinal water exudation and directly inhibit the adhesion and proliferation of pathogens (such as Escherichia coli and Salmonella). It repairs intestinal mucosal damage through antioxidant and anti-inflammatory effects. Compared with traditional feed, diarrhea can be controlled without antibiotics, avoiding the risks of drug resistance and residues.

[0028] (2) The present invention adopts a multi-stage extraction process of organic acid activation + reflux extraction + ultrasonic-assisted extraction to improve the utilization rate of active ingredients. The citric acid solution activation combined with ethanol stepwise extraction significantly improves the extraction rate of tannic acid compared with the traditional water extraction method. Freeze-drying preserves the activity of heat-sensitive ingredients and avoids the degradation of heat-sensitive ingredients caused by traditional high-temperature drying.

[0029] (3) Reuse of secondary and tertiary filter residues: This invention mixes and extracts secondary filter residues with willow branches to further utilize the active ingredients in the secondary filter residues and combine them with salicylic acid to further improve intestinal function; This invention mixes and ferments tertiary filter residues (rich in cellulose) with soybean meal and wheat bran, and after enzymatic hydrolysis by cellulase and protease, generates small molecule peptides and short-chain fatty acids, which significantly improves protein digestibility and nitrogen utilization, dynamically regulates temperature, humidity and gas environment, promotes enzyme production by EM agents, further decomposes anti-nutritional factors, and releases available nitrogen sources.

[0030] (4) Probiotics and antioxidants work together to enhance immunity. Lactic acid bacteria inhibit the colonization of pathogenic bacteria, yeast metabolites (such as β-glucan) activate intestinal immune cells, and antioxidants scavenge free radicals, reducing the damage of oxidative stress to the intestinal mucosa, forming a dual immune protection with gallnut extract.

[0031] (5) This invention generates porous corn kernels by controlling gradient temperature and pressure, thereby improving starch gelatinization and energy supply efficiency. Detailed Implementation

[0032] The technical solutions in the embodiments of the invention are described clearly and completely below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0033] Example 1

[0034] Step 1: Dry the gallnut and willow branches at 45℃ until the moisture content is ≤5%, then pulverize them into 45-mesh powder. Mix the gallnut powder with a citric acid solution with pH 5.0 at a solid-liquid mass ratio of 1:8, and stir at 45℃ and 120 rpm for 2 hours to obtain an activated solution.

[0035] Extraction agent one was added to the activation solution at a volume ratio of 1:1, and the mixture was refluxed at 72℃ for 2 hours. After filtration through a 200-mesh filter, primary filtrate and primary residue were obtained. Extraction agent one was added to the primary residue at a mass ratio of 1:1, and the mixture was ultrasonically extracted at 55℃ and 40kHz for 40 minutes. After filtration through a 200-mesh filter, secondary filtrate and secondary residue were obtained. The primary and secondary filtrates were combined and dried at -25℃ and 15Pa to obtain gallnut tannins.

[0036] The secondary filter residue, willow twig powder, and extractant two were mixed at a mass ratio of 2:1:4, refluxed at 72℃ for 2 hours, and filtered through a 200-mesh filter to obtain a tertiary filtrate and a tertiary filter residue. The tertiary filtrate was dried at 28℃ to obtain a gallnut-willow twig extract. Extractant one was anhydrous ethanol, and extractant two was a mixture of ethanol and ethyl acetate at a mass ratio of 2:1.

[0037] Step two: Grind the corn into a 25-mesh powder, then put it into an extrusion device for extrusion.

[0038] First stage: 120℃, 250rpm, material moisture content 17%.

[0039] Second stage: 100℃, 300rpm, inject 0.1MPa water vapor.

[0040] The third stage: at 80℃ and 230 rpm, dehydrate at -0.08 MPa until the moisture content is ≤7%, to obtain puffed corn.

[0041] Step 3: Mix forage, soybean meal, wheat bran, and tertiary filter residue in a mass ratio of 10:7:3:4 and pulverize to 25 mesh to obtain the base material. Add EM inoculant to the base material at a mass ratio of 50:1, then adjust the moisture content to 65% with enzymatic hydrolysate. Ferment at 35℃, 55% humidity, and 12% oxygen concentration for 12 hours, turning the mixture every 2 hours. Then, statically ferment at 45℃, 60% humidity, and 13% carbon dioxide concentration for 24 hours, followed by maturation at 60℃ and 28% humidity for 12 hours. After fermentation, inactivate the enzymes at 90℃ for 15 minutes to obtain the pretreated base material. The enzymatic hydrolysate contains 1800-2200 U / g of cellulase, 4800-5200 U / g of xylanase, and 3800-4200 U / g of protease.

[0042] Step four: Mix the pretreated base material, extruded corn, gallnut tannins, gallnut-willow twig extract, mineral salts, and probiotics in a mass ratio of 63:32:5:12:1:0.1 and granulate to a particle size of 3-5 mm with a particle moisture content ≤8%, to obtain gallnut tannin feed. The mineral salts include sodium chloride, calcium hydrogen phosphate, and magnesium sulfate in a mass ratio of 3:1:2. The probiotics include lactic acid bacteria and yeast in a mass ratio of 3:1.

[0043] Experimental Example 1

[0044] 1. Laboratory animals

[0045] Forty healthy, 3-month-old Holstein calves with similar body condition and birth weight were selected and divided into four groups of 10 each.

[0046] Experimental group: fed with gallnut tannins prepared according to the method in Example 1.

[0047] Control group 1: fed with feed prepared according to the method of Example 1, but without gallnut tannins.

[0048] Control group 2: fed with gallnut tannins prepared according to the method of Example 1, but without gallnut-willow twig extract.

[0049] Control group 3: fed with feed prepared according to the method of Example 1, but excluding gallnut tannins and gallnut-willow twig extract.

[0050] 2. Feeding methods and cycle

[0051] Except for the type of feed, the other feeding methods were based on "Key Technologies for Calf Feeding and Management" by Sun Peng. The feed amount was the same for both the experimental group and the control group 1-3, and the feeding cycle was 45 days.

[0052] 3. Detection indicators

[0053] The content of tannic acid in gallnut tannic acid and the content of active ingredients in gallnut-willow twig extract were determined.

[0054] Weighing was performed before the start of the experiment and before morning feeding on day 45, and daily weight gain and feed conversion ratio were recorded.

[0055] Blood samples were collected using anticoagulant blood collection tubes before morning feeding on day 45. Plasma samples were collected after centrifugation at 2000 rpm for 10 minutes to detect the levels of IgA, IgG, and TNF-α in the blood.

[0056] The daily diarrhea rate was calculated as an average. The digestive and metabolic test began on day 30. Fecal and urine samples were collected using the total fecal collection method. Nitrogen deposition, urinary nitrogen excretion, urinary nitrogen excretion / nitrogen intake, and nitrogen deposition / nitrogen intake were measured.

[0057] Table 1. Active ingredients in Gallnut-Willow Twig Extract

[0058] Tannic acid (mg / g extract) 582.5±15.3 0.47±0.05 Salicylic acid (mg / g extract) - 452.5±11.6

[0059] Table 2. Assessment results of calf weight gain, nitrogen utilization, and plasma immune indicators.

[0060] Daily weight gain (kg / day) from day 1 to 45 1.165 1.106 1.106 1.038 Material weight ratio (kg / kg) 3.83 3.88 3.82 4.25 Diarrhea rate (%) 0.0196 17.9 0.0478 28.6 Nitrogen deposition (g / d) 37.1 48.5 43.6 38.3 Urinary nitrogen excretion (g / d) 25.1 33.1 31.8 39.1 Urinary nitrogen excretion / nitrogen intake (g / g) 0.212 0.249 0.232 0.303 Nitrogen deposition / nitrogen intake (g / g) 0.307 0.363 0.346 0.293 IgA content (μg / mL) 2326 2028 2151 1925 IgG content (g / L) 34.8 31.7 33.7 31.2 TNF-α (pg / mL) 346 366 354 383

[0061] As shown in Tables 1-2, the gallnut tannic acid and gallnut-willow twig extract prepared in this invention are rich in active ingredients such as tannic acid and salicylic acid, which can significantly control calf diarrhea, improve nitrogen utilization, and enhance calf immunity. The daily weight gain of the experimental group was significantly higher than that of the control group 1-3. Compared with the control group 1-3, the experimental group significantly reduced feed conversion ratio, urinary nitrogen excretion, diarrhea rate, and plasma TNF-α content, and significantly increased nitrogen deposition and plasma IgA content.

[0062] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for preparing gallnut tannin feed to improve calf diarrhea, nitrogen utilization, and immunity, characterized in that, Includes the following steps: Step 1: Mix and dry the gallnut and willow branches separately, then crush them. Mix the gallnut powder with organic acid solution in a solid-liquid manner to obtain an activated solution. Step 2: Add anhydrous ethanol to the activation solution, with a volume ratio of 1:1 between the activation solution and anhydrous ethanol. Reflux extraction and filtration are performed to obtain a primary filtrate and a primary filter residue. Anhydrous ethanol is added to the primary filter residue, with a mass ratio of 1:1 between the primary filter residue and anhydrous ethanol. Ultrasonic extraction and filtration are performed to obtain a secondary filtrate and a secondary filter residue. After combining all the primary and secondary filtrates, freeze-drying under vacuum is performed to obtain gallnut tannic acid. The secondary filter residue, willow twig powder and extractant II were mixed, refluxed and extracted, filtered to obtain tertiary filtrate and tertiary filter residue. After drying the tertiary filtrate, gallnut-willow twig extract was obtained. The second extractant is ethanol and ethyl acetate in a mass ratio of 2:

1. The mass ratio of the secondary filter residue, willow twig powder and extractant II is 2:1:4; Step 3: Mix the pretreated base material, puffed corn, gallnut tannic acid, gallnut-willow branch extract, mineral salts and probiotics in a mass ratio of (60-65):(30-35):(3-5):(10-12):(1-2):(0.1-0.2) and granulate to obtain gallnut tannic acid feed. The preparation method of the pretreated substrate is as follows: mix and crush pasture, soybean meal, wheat bran and three-stage filter residue to obtain substrate; add compound microbial agent to substrate; adjust the moisture content with enzymatic hydrolysate; ferment at 35-50℃, humidity 50-60%, and oxygen concentration 10-12% for 12-14 hours, turning it over once every 1.5-2 hours; then statically ferment at 45-50℃, humidity 55-65%, and carbon dioxide concentration 12-15% for 24-26 hours; then mature at 55-60℃ and humidity 25-30% for 12-14 hours; after fermentation, inactivate at 90-95℃ for 15-20 minutes to obtain pretreated substrate.

2. The method for preparing gallnut tannin feed according to claim 1, characterized in that, The compound microbial agent is an EM microbial agent.

3. The method for preparing gallnut tannin feed according to claim 1, characterized in that, The enzymatic hydrolysate contains 1800-2200 U / g of cellulase, 4800-5200 U / g of xylanase, and 3800-4200 U / g of protease.

4. The method for preparing gallnut tannin feed according to claim 1, characterized in that, The mineral salts mentioned in step three include sodium chloride, calcium hydrogen phosphate, and magnesium sulfate in a mass ratio of 3:1:

2.

5. The method for preparing gallnut tannin feed according to claim 1, characterized in that, The probiotics mentioned in step three include lactic acid bacteria and yeast, with a mass ratio of 3:

1.

6. Gallnut tannin feed prepared by the method according to any one of claims 1-5.