Infectious coryza is an acute respiratory disease caused by the bacterium Haemophilus paragallinarum and has been recognised since the 1930’s. Although a similar disease is found in quail and pheasants, it only affects chickens.
It’s a worldwide disease and can affect birds of all ages but is primarily seen in mature birds. In laying hens this can cause a reduction of egg production of up to 40% leading to economic damage. It has an incubation period of one to three days with the disease usually lasting two to three weeks.
The Cause of Coryza
Infectious coryza is caused by the bacterial disease called Haemophilus paragallinarum. It is present all over the world and can affect birds of any age however, mature birds are more at risk and can result in the reduction in production of layers.
Transmission
The disease passes by direct contact from bird to bird, through airborne droplets, contaminated feed and drinking water. It can also be spread across premises through equipment and clothing.
Clinical Signs
Some of the most common clinical signs include:
- Inflammation around the eyes and upper respiratory tract
- Conjunctivitis, with discharge from the nasal and sinuses
- A drop in feed and water consumption resulting in a loss of egg production
- Low weight gain and anorexia
- Facial swelling
Diagnosis
In recent years, significant developments for diagnosing infectious coryza have been implemented, including a PCR test that is specific for Haemophilus paragallinarum, which produces rapid results within six hours. An accurate diagnosis can also be made in the laboratory where a polymerase chain reaction test is carried out.
Treatment and Control
Early treatment with antibiotics can alleviate the severity and duration of the disease. However, once the treatment is stopped a relapse can occur as recovered birds remain carriers. Vaccination is the preferred method of control, but strict biosecurity should always be prioritised, as it is the most effective way to prevent disease incursion. In an outbreak the flock should be removed from the premises and the whole area cleaned and disinfected. The premises should not be used for three weeks after disinfection.
Livetec are here to support bird keepers
Livetec are the industry leaders in biosecurity. We have a range of unique biosecurity services, and create bespoke plans that are designed to mitigate the risk of infection and protect the welfare of your flock and your farm business. Our plans encompass best practices, unique evidence based thinking and the latest legislation.
Expert advice from the experts
A key service that we offer, designed to enhance on-farm disease prevention is our Biosecurity Advisory Service, backed by years of on-farm experience and evidence based research. With this robust service, our experts conduct an on-site review of your operations and advise you on the ways in which you can implement the most effective biosecurity measures.
To find out more about how our services can help you, click here.
