Infectious Coryza is like a chicken getting a serious cold. It is a common respiratory disease caused by bacteria that invade chickens’ respiratory tracts.
Infectious coryza is usually difficult to distinguish from diseases such as avian influenza, Newcastle disease, infectious laryngotracheitis, and infectious bronchitis, but understanding the specific symptoms of infectious coryza can help you identify this infection in your flock.
In addition to understanding the symptoms of infectious coryza, the prevention and treatment of this disease are also essential for the healthy growth of the flock and the stability of egg production.
What is infectious coryza in chickens?
Infectious coryza is an acute respiratory disease of chickens caused by Paragallinarum Avibacterium, a bacterium that apparently affects only chickens. Reports from quail and pheasants may describe a similar disease caused by a different bacterium.
Clinical signs include decreased activity, nasal discharge, sneezing and facial swelling. Occurs primarily in pullets and laying hens and occasionally in broilers. Usually occurs in adult chickens; susceptibility increases with age; however, the disease has also been reported in very young chicks (e.g., 2 weeks of age).
Can chicken infectious coryza be transmitted to humans?
Chicken infectious coryza is a disease caused by the bacterium Paragallinarum Avibacterium that usually only infects chickens, especially laying hens. Chicken infectious coryza is not a zoonotic disease, so it is not usually contagious to humans.
The cause of chicken infectious coryza?
Chicken infectious coryza is an acute respiratory infectious disease caused by chicken infection with Paragallinarum Avibacterium. Most Haemophilus need to rely on factor V (NAD) to grow in vitro, but there are also Haemophilus that do not rely on factor V to grow.
How does chicken infectious coryza spread?
The transmission methods of chicken infectious coryza include direct contact, air contact and indirect contact. Once the flock is infected, all chickens are considered carriers.
Direct contact transmission: Healthy chickens may be infected as long as they come into contact with the secretions of sick chickens, such as snot, tears, saliva, etc. These secretions contain a large amount of the pathogen Paragallinarum Avibacterium.
Airborne transmission: The secretions of sick chickens can form aerosols in the air, and healthy chickens may also be infected by inhaling these aerosols.
Indirect transmission: Contaminated feed, drinking water, appliances, equipment, means of transportation, or personnel’s clothing, shoes, etc. may become vectors of transmission, bringing germs to healthy chickens.
Bird transmission: Wild birds or other birds may become communicators, especially in open environments. They can carry the pathogen to different flocks of chickens, spreading the disease.
Since the disease is transmitted mainly through contact and droplets, once an epidemic occurs in the flock, measures such as isolation, disinfection, and monitoring of healthy chickens are usually required to control the spread of the disease.
Transmission cannot occur through eggs, so if an infected bird lays eggs, it will not have the disease.
Non-infected chickens exposed to infected chickens are also considered carriers of the disease, even if they never show any symptoms. This is because chickens can build immunity to bacteria without showing any symptoms of infection. Despite their immunity, they can still spread the disease to other chickens that are not immune to infectious coryza.
Clinical diagnosis of chicken infectious coryza?
The clinical symptoms of chicken infectious coryza mainly include：
- Reduced activity
- Foul-smelling nasal secretions
- Sneezing
- Facial swelling
- Watery eyes
Affected birds will experience diarrhoea, and in the acute stage of the disease, feed and water consumption is usually reduced.
Chickens with this disease may reduce egg production.
The detection method of chicken infectious coryza?
Usually, bacterial culture and PCR detection
Bacterial culture: Catalase-negative organisms are the diagnosis of infectious coryza. Catalase-specific testing is essential because catalase-positive non-pathogenic organisms are present in both healthy and diseased chickens.
PCR detection: PCR detection is a high-sensitivity and high-specificity nucleic acid detection method that can quickly and accurately detect infectious coryza in chickens.
Because there are three serotypes of chicken infectious coryza (serotype A, serotype B, and serotype C), there is no suitable serological test for it.
Wixbio recommends: combining the clinical symptoms of chickens with the comprehensive determination of PCR detection/bacterial culture, first determine whether it is a respiratory disease of chickens from the clinical symptoms, and then further determine whether it is an infectious coryza disease through PCR detection or bacterial culture.
Treatment of chicken infectious coryza?
In the event of an outbreak of infectious coryza in chickens, the chickens should be removed from the premises, and the entire area should be cleaned and disinfected. The premises should not be used within three weeks after disinfection. Once quarantined, infected chickens will be easier to care for and treat. Ensure that the quarantined chickens are safe and protected and have access to food and water. You can also provide supplementary probiotics during this period to help improve intestinal health.
When proper preventive care is given to infected chickens, the swelling should subside within 14 days, but other symptoms may last for several months.
Infectious coryza can be relieved with many antibiotics (such as erythromycin and oxytetracycline, etc.), but they will not treat the infection. It is necessary to improve the immunity of chickens to help them resist the virus. Most antibiotics cannot be used on laying hens because they require a withdrawal period and are not approved for use in animals that provide food. In severe outbreaks of infectious coryza, even if the treatment results improve, recurrence may still occur once the treatment is stopped because the recovered birds are still carriers. Therefore, if you want to raise chicks in an infected place, you can use a combination of preventive drugs and vaccination.
Prevention of chicken infectious coryza
Some health-care drugs can be used to prevent chicken infectious coryza. Since serotypes A, B and C are not cross-protected, it is very important that health-care drugs contain serum present in the target group. Vaccines are used to prevent infections in high-incidence areas. Vaccination should be completed between 10 and 20 weeks of age, and chicks will be basically protected by two injections administered about 4 weeks apart before 20 weeks of age.
Once vaccinated, all chickens in the flock must be re-vaccinated twice a year in a row to make the vaccination contagious.
Wixbio vaccination program：
12 weeks: The first vaccination of the trivalent vaccine for infectious coryza (serotype A + serotype B + serotype C).
16 weeks: The second vaccination of the trivalent vaccine for infectious coryza (serotype A + serotype B + serotype C).
Note: It is best to inoculate in a constant temperature room to keep the flock site dry because after vaccination, it will cause local skin to leave needle eyes, and water can easily cause local inflammation, which affects the effect of the vaccine in preventing diseases.