Chicken respiratory disease is still the most serious disease that harms the chicken industry at present. At present, many methods are used to prevent and treat this kind of disease, such as mixing materials, drinking water, individual administration or injection, and some methods are ineffective because drugs can not reach the respiratory tract; Although some methods can reach the respiratory tract, due to the different distribution of drugs in the body, liver metabolism and kidney excretion, the efficacy is reduced and it is time-consuming and laborious. Aerosol spray inhalation provides the best method to treat poultry respiratory diseases.
1 characteristics of aerosol inhalation administration
1. 1 The drug can be absorbed quickly, and it can reach the action site directly, and the drug effect appears quickly. Oral administration, most drugs need to diffuse through the gastrointestinal mucosa and be absorbed into the blood circulation, and then distributed to the corresponding parts with the blood flow to play a role. This not only requires a process, but also drugs are easily affected by various enzymes and pH values in the gastrointestinal tract. In addition, the drug is not fully absorbed in the small intestine, which slows down or even reduces the efficacy. Although intramuscular injection is fast to absorb, it is time-consuming and laborious, and sometimes it will cause human injury to chickens. In addition, the amount of drugs reaching respiratory mucosa through blood is insufficient, which affects the curative effect. Inhalation can make the drug directly reach the lung and air sac, which can not only avoid the adverse stimulation of the drug to the gastrointestinal tract, but also avoid the metabolic degradation of the drug by the liver and gastrointestinal tract. In addition, due to the large alveolar area, abundant capillaries and fast drug absorption. The bioavailability of some drugs is close to 100%, while the bioavailability of oral administration is only 20%( 1).
1.2 can exert the systemic and local therapeutic effects of drugs, and the therapeutic effect is strong.
1.2. 1 The rate at which drugs enter the blood from alveoli is affected by periodic breathing, that is, lung clearance, and intermittently enters alveoli. Some drugs can penetrate the alveolar barrier and exert systemic effects. After some drugs are absorbed, they can only stay in the alveoli, not easily penetrate the alveolar barrier, and can only play a local role (2).
1.2.2 There are air sacs in the respiratory system of chickens that mammals do not have, which can increase lung ventilation and enhance lung gas exchange. At the same time, the chicken's lungs don't expand and contract like those of mammals, but the gas passes through the lungs and enters and exits the airbag with the pipes in the lungs. This structural feature of the respiratory system can expand the area of drug diffusion and increase the absorption of drugs. In addition, inhalation administration can directly attach a large number of drugs to the surface of the airbag, completely killing pathogens on the airbag.
1.3 is time-saving and labor-saving, with accurate and uniform drug inhalation and good therapeutic effect. Inhalation can reduce the labor intensity of mixing materials, drinking water or catching chickens, and reduce the stress response of chickens. For chickens that can't eat or drink water, drugs can quickly reach trachea, bronchus and other parts through breathing, effectively inhibiting or killing pathogenic bacteria and playing a therapeutic role.
Mechanism of inhalation in the treatment of respiratory diseases
The occurrence of respiratory diseases is mostly due to the invasion of pathogenic microorganisms into the respiratory system, causing respiratory inflammation, producing a large number of secretions and forming sputum. Inflammation develops further, which makes respiratory mucosa hyperemia and bleeding, thus causing mucosa to fall off, forming embolus, blocking larynx and trachea, forming a large number of cheese-like substances on airbag, and presenting symptoms such as mouth opening and neck stretching, shaking head, cough, asthma, tracheal rales and so on. Therefore, antibacterial and antiviral drugs should be selected to kill pathogenic microorganisms and prevent secondary infection. The acidic mucopolysaccharide fibers in sputum are cracked by expectorant drugs, so as to reduce the sialic acid content in sputum, reduce the viscosity of sputum and make it easy to cough up, thus relieving cough and relieving symptoms. Combined with bronchodilator, it relaxes bronchial smooth muscle and is beneficial to sputum discharge. Therefore, the general principle of medication should be anti-bacterial, anti-inflammatory, expectorant and antiasthmatic, and treat both the symptoms and the root causes in order to achieve the purpose of treatment.
3 commonly used drugs and doses for inhalation administration
3. 1 antibiotic
3. 1. 1 long-acting antibacterial Alex Gao (1996) reported that according to each henhouse (8×25×2.2m3).
Every time 15 kg tap water and 5 bottles of long-acting antibacterial agent (produced by Veterinary Medicine Branch of North China Pharmaceutical Factory) are fully dissolved, chronic respiratory diseases of chickens are treated at 5 am and 9 pm every day. It improved after 3 days, recovered after 5 days, and did not improve after drinking the water of Gaolimi first (3).
3. 1.2 streptomycin Wang Xiaohua et al. (1993) reported that 1g (1 10,000 IU) streptomycin was diluted to 2ml with physiological saline, sprayed at 200000 U/m3, sprayed at10-30μ m.
3. 1.3 neomycin and kanamycin neomycin can be sprayed 1g/m3 and inhaled1.5h; Every time; Treatment of chronic respiratory diseases with kanamycin 0.5ml/m3 spray.
3. 1.4 nystatin is sprayed with 50 units /m3 for 30-40 minutes at a time, which can be used to treat lung diseases caused by Aspergillus infection.
3. 1.5 quinolones (such as ofloxacin and enrofloxacin) were sprayed at a dose of 0.5g/m3 to treat chronic respiratory diseases, and the effect was good.
3. 1.6 Luo (1996) reported that 6g of sulfathiazole, 0.3g of furacilin, 0.8 g of vanadate/kloc-0 and 900,000 IU of various antibiotics can be used per cubic meter of aerosol to treat respiratory diseases. Li Yilan et al. (1994) reported that each chicken was given streptomycin 20,000 units, gentamicin 0.6-1000 IU and hydrocortisone 0.6ml aerosol.
3.2 expectorant drugs
3.2. 1 acetylcysteine ester is generally made into aerosol with 3ml 10-20% sodium acetylcysteine solution, 0.25 ml isoproterenol (1∶200 solution) and EDTA as stabilizers.
3.2.2 TEG carefully mix 300g iodine tablets, 160g potassium iodide and 9 15 ml TEG until they are completely dissolved, and then add 20ml lactic acid and 2000ml pure tap water to 1000ml TEG solution. When used, according to the dosage of 65438+2.8 ml/m3 for chicks aged 05-25 days, 2.7ml/m3 for chicks aged less than 35 days and 2.5 ml/m3 for older chicks, use 12d at intervals. Spray 10 minute each time, and then close the henhouse for 25 minutes.
3.3 Antiasthmatic drugs and bronchodilators
3.3. 1 dihydroxyphenyl isopropyl amino carboxylic acid This drug can bind to adrenergic β2 receptors in bronchial vascular beds and other parts, relax bronchial smooth muscle, reduce pulmonary and systemic circulation resistance, and increase cardiac output. The general dose of 1- 10-day-old chicks is 2mg/kg body weight.
3.3.2 Luo (1996) reported that aminophylline aerosol (0.3g/m3), ephedrine aerosol (0.3g/m3) and atropine aerosol (15g/m3) are special aerosol for anti-bronchitis. To promote the absorption of respiratory secretions, sodium bicarbonate 1 1g, ammonium chloride 6g, trypsin 25mg, deoxyribonuclease 25mg or ribonuclease 25mg can be used simultaneously per cubic meter.
4 Matters needing attention in inhalation administration
4. 1 Choosing drugs suitable for inhalation requires that the drugs used are neither irritating to the respiratory tract of birds, but also soluble in their secretions, otherwise they cannot be absorbed. In order to increase the stability of the drug, antioxidants such as vitamin C and sodium metabisulfite can be added.
4.2 Control the droplet size, the smaller the droplet, the deeper it enters the lung, but the worse the retention rate in the lung, most of it is easily discharged from the breath, which affects the drug effect. When the droplets are large, most of them fall on the surface of respiratory mucosa, fail to enter the lungs, and are absorbed slowly. According to the comprehensive research results, the appropriate droplet size is 0.5-5μl for lung and 10-30 μ l for upper respiratory tract. ..
4.3 Grasping the hygroscopicity of drugs To make the particles reach the deep part of the lungs, drugs with slower hygroscopicity should be selected. Because hygroscopic drug particles can gradually increase in diameter when passing through the respiratory tract with high humidity, which affects the drug reaching the alveoli, thus affecting the curative effect.
4.4 Grasp the dosage of the same drug by inhalation, which may be different from other dosage forms and cannot be used at will. For drugs that can be absorbed by lungs and air bags, the effective dose should be determined by measuring the absorbed blood concentration. Drugs with low safety factor must be tested for toxicity to ensure safety.
4.5 If aerosol is made for inhalation administration, an ideal propellant should be selected. The ideal propellant condition is that the vapor pressure at room temperature is greater than atmospheric pressure; Non-toxic, no allergic reaction and irritation; Non-explosive and non-flammable; Colorless, odorless, tasteless, stable in nature, and does not react with drugs and containers. , and cheap and easy to get. Commonly used are chlorofluorocarbons and compressed gases, such as inert gases such as CO2 or N2.
4.6 Inhalation therapy is best carried out at night or in the dark, so as to reduce the operation noise and avoid panic and stress reaction affecting the productivity of chickens. After spraying, the henhouse should be sealed for 30-60 minutes. In addition, pay attention to the personal protection of the operator to avoid the harm of some drugs to the human body.
How to idealize aerosol administration
First, the purpose of atomization inhalation administration:
The routes of administration for broilers are mostly mixing materials, drinking water, individual drip, intramuscular injection or subcutaneous injection. Due to the unique physiological structure of poultry, the above administration routes can not achieve the best therapeutic effect on respiratory diseases of broilers. At present, aerosol administration has been gradually recognized by the industry as a way of administration, but there are still many problems in the specific operation. Therefore, according to the clinical practice of aerosol administration, we systematically summarized the equipment, equipment operation and drug combination of aerosol, hoping to provide useful technical reference and guidance for on-site veterinarians. The purpose of aerosol administration is to relieve the respiratory symptoms of broilers, promote sick chickens to eat drinking water, win time and effect for the administration of other therapeutic drugs, and achieve treatment or help broilers to achieve normal slaughter.
Second, aerosol spray drug delivery equipment and operation method:
1, aerosol spraying equipment:
The equipment must be able to solve the three problems of droplet size, noise and spraying speed. The equipment we provide is imported fan combined with domestic high-pressure hose and watering can spraying equipment. Fan power 1.0 kW, voltage 220V v.
2, aerosol administration operation:
1) fog adjustment:
The suitable diameter of fog particles is 10-20 microns. First, put clean water in the watering can, start the equipment, lift the watering can horizontally, and stretch out your arm two meters away from the watering can. Facing the light, you can see 1-2 small water droplets sticking to the hair of your arm, which shows that the water droplets are of the right size.
2) Power supply inspection:
According to the electricity consumption of spraying equipment and other henhouse appliances, the load of henhouse transmission line is measured to prevent the line from catching fire due to excessive current.
3) Number of aerosol spray delivery equipment:
Each spraying equipment can be used by 5000 chickens, and the spraying time is about 30 minutes. If there are too many chickens, consider increasing spraying equipment.
4) Dust removal in henhouse:
When the relative humidity in the henhouse is low and the dust is heavy, before spraying (spraying to the top of the henhouse), the henhouse should be humidified and disinfected with nozzles (nozzles) based on the clear visibility of the henhouse.
5) Indoor environment control:
Increase the indoor temperature before humidification and dust removal in the house, so that the indoor temperature can meet the age temperature requirements after dust removal. Stop the fan when spraying aerosol (close the window in summer).
6) dispensing medicine
Dilute the drug (see III for dosage. Prescription) into liquid medicine, with 3-4L liquid medicine for every 1000 chickens. After spraying, it is advisable to fog the henhouse.
7) Spraying time:
Spray in the early morning in summer, turn off the lights at night in other seasons, and wait until the chickens are quiet. For severe chickens, finish spraying at night and spray again in the early morning of the next day, with an interval of 6-8 hours.
8) Spray:
Lift the watering can horizontally, so that the aerosol falls from the height of more than one meter away from the chicken's back, and each falling point is 2 meters away from the watering can (this position is the most suitable for droplets). Turn on the light and observe that the room is full of aerosols, and the visibility is 5- 10 meter, indicating that the dosage of the medicine is up to standard. Wait 30-60 minutes before opening doors, windows or fans. Note: people who are allergic to spraying drugs are forbidden to appear on the scene. Operators should wear goggles and masks to avoid the harm of some drugs to human body.
Third, the mechanism of aerosol spray in the treatment of respiratory diseases:
The occurrence of respiratory diseases is mostly due to the invasion of pathogenic microorganisms into the respiratory system, causing respiratory inflammation, producing a large number of secretions and forming sputum. The inflammation develops further, which makes the respiratory mucosa hyperemia and bleeding, thus causing the mucosa to fall off, forming embolism, blocking the larynx and trachea, forming a large number of cheese-like substances on the airbag, and presenting symptoms such as mouth opening and neck stretching, shaking head, cough, asthma, and tracheal rales. Therefore, antibacterial and antiviral drugs should be selected to kill pathogenic microorganisms and prevent secondary infection. The acidic mucopolysaccharide fibers in sputum are cracked by expectorant drugs, so as to reduce the sialic acid content in sputum, reduce the viscosity of sputum and make it easy to cough up, thus relieving cough and relieving symptoms. Combined with bronchodilator, it relaxes bronchial smooth muscle and is beneficial to sputum discharge. Therefore, the general principle of aerosol administration should be antibacterial and anti-inflammatory, expectorant and antiasthmatic, and treat both the symptoms and root causes to achieve the purpose of treatment.
First, the choice of state (chicken): when the symptoms of a large group of respiratory tract are above 20%, the effect of whole group aerosol administration can be better. When it is less than 20%, local aerosol administration can be selected, and the whole group of aerosol administration is not recommended.
Second, the choice of drugs: mainly according to the location of respiratory diseases (the composition of respiratory system)
Aerosol administration preparation
I. Upper respiratory tract infection (above the tube)
* Mucus is below the throat, with a clear voice but a purr.
* Snuff, swing.
* There is mucus in the upper trachea.
* Laryngeal bleeding
Prescription: Hepatobiliary Oral Liquid+Erythromycin Thiocyanate (Tylenol)
Drug dosage: 800- 1000ml/5000 chickens each time, and the dosage of antibiotics is 1/3- 1/2 of the oral dosage.
Dilution method: 1. Calculate the amount of water needed for aerosol administration. 2. The water temperature is not suitable for hot water (destroying medicinal properties). 3. Add one medicine, and then add the second medicine after the medicine is dissolved, and stir evenly. (Cannot be added at the same time)
* There is mucus in the tube, which makes a dull purr.
Prescription: Hepatobiliary Oral Liquid+Doxycycline and Neomycin!
Drug dosage: 600-800ml/5000 chickens each time, and the antibiotic dosage is 1/3- 1/2 of the oral dosage.
Dilution method: 1. Calculate the amount of water needed for aerosol administration. 2. The water temperature is not suitable for hot water (destroying medicinal properties). 3. Add one medicine, and then add the second medicine after the medicine is dissolved, and stir evenly. (Cannot be added at the same time)
B, lower respiratory tract infection:
* There is mucus and annular bleeding in the bronchus, which can be scraped off with scissors (note: the blood of viral diseases is in the meat and cannot be scraped off).
* Difficulty in breathing, from mouth opening to asthma.
Prescription: Hepatobiliary Oral Liquid+Roxithromycin.
Drug dosage: 800- 1000ml/5000 chickens each time, and the dosage of antibiotics is 1/3- 1/2 of the oral dosage.
Dilution method: 1. Calculate the amount of water needed for aerosol administration. 2. The water temperature is not suitable for hot water (destroying medicinal properties). 3. Add one medicine, and then add the second medicine after the medicine is dissolved, and stir evenly. (Cannot be added at the same time)
C, lung infection:
* The lungs are purple and congested. If you put them in water, they will sink.
Prescription: Gan 'an oral liquid+tilmicosin (azithromycin).
Drug dosage: 600-800ml/5000 chickens each time, and the antibiotic dosage is 1/3- 1/2 of the oral dosage.
Dilution method: 1. Calculate the amount of water needed for aerosol administration. 2. The water temperature is not suitable for hot water (destroying medicinal properties). 3. Add one medicine, and then add the second medicine after the medicine is dissolved, and stir evenly. (Cannot be added at the same time)
* Lung necrosis with yellow cheese.
Prescription: Hepatobiliary Oral Liquid+Florfenicol+Doxycycline.
Drug dosage: 800- 1000ml/5000 chickens each time, and the dosage of antibiotics is 1/3- 1/2 of the oral dosage.
Dilution method: 1. Calculate the amount of water needed for aerosol administration. 2. The water temperature is not suitable for hot water (destroying medicinal properties). 3. Add one medicine, and then add the second medicine after the medicine is dissolved, and stir evenly. (Cannot be added at the same time)
* Lung atrophy, no color.
Prescription: Hepatobiliary Oral Liquid.
Dosage: 600-800 ml /5000 chickens each time,
Dilution method: 1. Calculate the amount of water needed for aerosol administration. 2. The water temperature is not suitable for hot water (destroying medicinal properties). 3. Add one medicine, and then add the second medicine after the medicine is dissolved, and stir evenly. (Cannot be added at the same time)
D, airbag infection, airbag turbidity, yellow and white cheese.
Prescription: Hepatobiliary Oral Liquid+Ligamycin (or Tamithromycin).
Drug dosage: 800- 1000ml/5000 chickens each time, and the dosage of antibiotics is 1/3- 1/2 of the oral dosage. (Note: Tamiflu is incompatible with polyether antibiotics. )
Dilution method: 1. Calculate the amount of water needed for aerosol administration. 2. The water temperature is not suitable for hot water (destroying medicinal properties). 3. Add one medicine, and then add the second medicine after the medicine is dissolved, and stir evenly. (Cannot be added at the same time)
Maintenance measures in the house: temperature and ventilation.
Fourth, personnel safety measures: protection, different people have different sensitivities to drugs, so it is necessary to strengthen the safety of protective personnel.
Verb (abbreviation of verb) Maintenance measures after aerosol: It is very important to take good care of chickens.
Other matters that need to be explained.
1. The best age for aerosol spray administration is 14-25 days.
2. If the chicken has a fever, add antipyretic drugs to the drinking water before aerosol administration, and let the chicken drink water immediately after spraying, which has obvious effect on restoring the drinking water.
3. After each aerosol spray administration, other therapeutic drugs (antiviral drugs and antibiotics) should be administered subsequently to treat symptoms and root causes.
Attachment:
Streptomycin: 1g( 1 million IU) streptomycin is diluted to 2ml with physiological saline, sprayed at a speed of 200000 U/m3, and the droplets are10-30μ m. After spraying, doors and windows are sealed for 30-60min, which is used to treat chronic respiratory diseases.
Neomycin and kanamycin: Neomycin can be sprayed at the speed of 1g/m3 and inhaled at1.5h; Every time; Treatment of chronic respiratory diseases with kanamycin 0.5ml/m3 spray.
Nystatin: Spraying nystatin at a rate of 50 units /m3 for 30-60 minutes each time can treat lung diseases caused by Aspergillus infection.
Quinolones (such as ofloxacin and enrofloxacin): Aerosol spray can be administered at a dose of 0.5g/m3 to treat chronic respiratory diseases with good effect.
4. The aerosol sprayer of Qingdao Zhong Rui Instrument Company is recommended here.
ZR-40 10 medical aerosol generator PatentNo.: ZL2009203 1304 1.0.
Patent number: zl201030237024.1+0.