Spray administration for the treatment of avian respiratory diseases

Spring is a season of high incidence of avian respiratory diseases, but it has long been a poor effect due to a variety of factors. In recent years, through repeated clinical practice, the author applied spray administration method to treat chicken respiratory diseases and achieved good results.

First, why are respiratory diseases more difficult to treat?

The respiratory tract is the gateway for the exchange of gas between the chicken body and the outside world. The swing of the cilia of the respiratory tract can remove the pathogenic bacteria from the outside and act as a natural barrier. Once stress has broken this barrier, many diseases will be uninvited; and high-density farming environment is very likely to cause mixed infection of many pathogens. In addition, the physiological characteristics of poultry, respiratory diseases often cause air sac In the case of drinking water, mixing and injection, the drug is absorbed into the bloodstream, and few can reach the airbag. This is the main cause of refractory respiratory diseases.

1 The influence of stress factors such as spring climate leads to frequent respiratory diseases. The spring climate is dry, the temperature is hot and cold, the temperature difference between day and night is large, and various stress factors increase. It is easy to destroy the integrity of the upper respiratory tract mucosa, so that the ability of rejection is reduced, leading to the pathogenesis of various pathogens.

2 The physiological characteristics of poultry make it difficult to cure respiratory diseases. It can be seen from the anatomy of poultry that the nasal cavity is the portal for the respiratory tract, and if the mucosa is damaged, it will cause a series of lesions. For example, when the temperature of the house is high, the chicken will breathe in order to evaporate heat. Three-fourth of the gas that the chicken inhales enters the airbag first, which is prone to airbag disease. Because there are only a small number of blood vessels and nerves on the trachea and airbags, the tissue concentration of the drug is low, and the absorption and utilization rate is poor, which is often difficult to cure.

3 The therapeutic effect of respiratory diseases has a great relationship with the mode of administration. In the method of administration of poultry, the most commonly used are drinking water, mixing and injection. Although the injection medicine is absorbed quickly, it takes time and effort, and the stress is large, which affects the growth. The so-called "grab the chicken once, three days is not long" is the reason. Drinking water and mixing materials, most of the drugs need to diffuse through the gastrointestinal mucosa and be absorbed into the blood circulation, followed by blood distribution to the corresponding parts to play, but only a small number of blood vessels and nerves on the trachea, balloon, transported to the tissue There are few drugs, resulting in a very low concentration of tissue distribution; and the drug must reach the small intestine through the mouth and stomach after oral administration. In this process, the drug is susceptible to various enzymes and pH in the gastrointestinal tract, so that the drug can be bioavailable. The rate is significantly reduced, so it is difficult to achieve effective treatment.

Second, respiratory disease spray application effect is good

Spray administration is not only simple and convenient, saves time and effort, and can directly reach the lesion site, play a therapeutic role, and significantly improve the bioavailability of the drug; at the same time, it can avoid the adverse stimulation of the drug to the gastrointestinal tract, reduce the liver, Kidney damage. For chickens with severe mixed infection, dying, no food or drink, severe air sacs, spray administration can quickly control death, quickly relieve respiratory symptoms, reduce stress response in flocks, and facilitate disease recovery. Studies have shown that the effect of spray administration is 10-20 times higher than that of drinking water.

1 spray administration can directly reach the lesion site and quickly play a role. Spray administration can directly act on the respiratory mucosa system, directly contact with the diseased tissue, maintain a high drug concentration in the inflammatory site, directly anti-inflammatory, sterilize, rapidly repair damaged epithelial mucosal cells, and improve the immune protection of the body. Barrier; In addition, due to the large alveolar area and abundant capillaries, the drug can be widely distributed and rapidly absorbed, greatly improving the bioavailability of the drug.

The respiratory characteristics of the two poultry determine that the best mode of administration for respiratory diseases is spray administration. The chicken has an air bag. The structural characteristics of the respiratory system can expand the diffusion area of ​​the drug and increase the absorption of the drug. At the same time, the inhalation administration can directly adhere the drug to the surface of the balloon, and completely kill the pathogen on the balloon. Especially for chickens that cannot eat or drink water, spray administration can quickly reach the trachea and bronchi as well as airbags, etc., effectively inhibiting or killing pathogenic bacteria, and has a therapeutic effect. Such as steroids, direct contact with the tracheal mucosa can regulate the secretion of serum and mucus, making the sputum thin, easy to cough up.

3 The special breathing mode of the birds makes the spray administration more reasonable. When inhaling, part of the fresh air enters the pulmonary capillary, and most of it enters the posterior chest balloon and the abdominal balloon. The air exchanged by the air enters the cervical balloon, the clavicular balloon, and the chest balloon. When exhaling, the gas of the cervical balloon, the clavicle balloon, and the chest balloon is discharged by the trachea, and the fresh air in the posterior thoracic balloon and the abdominal balloon enters the pulmonary capillary. Therefore, regardless of inhalation or exhalation, gas exchange can be performed in the lungs. Spray administration can directly contact the drug and the lungs, promote the synthesis of surfactants in the lungs, strengthen the ciliary oscillation, and increase the scavenging ability of the mucociliary transport system. Prevent repeated infections.

4 reduce or avoid the drug's adverse stimulation of the gastrointestinal tract, which is conducive to the rapid recovery of production capacity. Laboratory tests and clinical practice have shown that spray administration has a high tissue concentration in the lungs, but concentrations in the liver and kidneys are much lower than in oral administration, indicating that spray administration minimizes liver and kidney damage, for the liver at the end of the disease. In the case of flocks with severe kidney damage, spray administration minimizes flock death and facilitates rapid recovery of production capacity.

Third, the specific requirements of spray administration

1 drug selection. The required drugs are not irritating to the respiratory tract of the birds, do not damage the respiratory mucosa, and can dissolve into their secretions to facilitate absorption. At present, spray-type drugs specially used for spray administration on the market, such as Zhiyuanqing, long-acting antibacterial agents, etc., have good therapeutic effects, and should be selected for symptomatic use.

2 Before the administration, the house should be dusted and humidified. The house should be sprayed, dedusted and humidified before spraying, and sprayed at half an hour.

3 pay attention to heat preservation and moisturization to prolong the duration of drug action. When spraying, the ventilation facilities and lighting of the house should be turned off. In winter, the temperature inside the house should be 1-2oC higher than the normal temperature, and the humidity should be 65%-70%. After spraying, the house should be closed for 30-60 minutes.

4 control the size of the droplets. The dilution water should be cleaned. In spring, autumn and winter, the water temperature should be higher than the temperature in the house, 38-40oC is good; normal temperature can be used in summer. When spraying, choose a special spray equipment. The sprayer nozzle should be placed 30 cm above the chicken head, sprayed obliquely upward, and the droplet size should be properly controlled. The diameter of the droplet particles is preferably 40 μm or less.

5 Spray administration is preferably carried out at night. According to pharmacodynamic studies, the therapeutic effect of respiratory diseases is closely related to the time of administration. Clinical practice has shown that spray administration at 18-20 in the evening is the best, which can control respiratory symptoms in the shortest time, minimize mortality, and minimize stress response; the number of medications is usually 1 time / Days, for 2-3 days.

In addition, the spray should be paid attention to the operator's personal protection, such as wearing a mask, protective glasses, etc., in order to prevent certain drugs from causing damage to the human body.