Infectious Coryza

A usually acute, sometimes chronic, highly infectious disease of chickens, occasionally pheasants and guinea-fowl, characterised by catarrhal inflammation of the upper respiratory tract, especially nasal and sinus mucosae. Infectious Coryza is caused by the bacterium Haemophilus paragallinarum and is seen in many countries especially in multi-age farms that are never depopulated. Morbidity is high but mortality low if uncomplicated although it may be up to 20%. This disease causes aasmus, swollen head, several bacteria in respiratory tract.

1.CAUSES

BỆNH SỔ MŨI TRUYỀN NHIỄM (infectious coryza)

Infectious Coryza is caused by the bacterium Haemophilus paragallinarum and is seen in many countries especially in multi-age farms that are never depopulated. Morbidity is high but mortality low if uncomplicated although it may be up to 20%. This disease causes aasmus, swollen head, several bacteria in respiratory tract.
The route of infection is conjunctival or nasal with an incubation period of 1-3 days followed by rapid onset of disease over a 2-3 day period with the whole flock affected within 10 days, resulting in increased culling. Carriers are important with transmission via exudates and by direct contact. It is not egg transmitted.

The bacterium survives 2-3 days outside the bird but is easily killed by heat, drying and disinfectants. Intercurrent respiratory viral and bacterial infections are predisposing factors.

2. SYMPTOMS AND DIAGNOSIS
Signs

Facial swelling.
Purulent ocular and nasal discharge.
Swollen wattles.
Sneezing.
Dyspnoea.
Loss in condition.
Drop in egg production of 10-40%.
Inappetance.

Post-mortem lesions

Catarrhal inflammation of nasal passages and sinuses.
Conjunctivitis.
Eye-lid adherence.
Caseous material in conjunctiva/sinus.
Tracheitis.

Diagnosis

A presumptive diagnosis may be made on signs, lesions, identification of the bacteria in a Gram-stained smear from sinus. Confirmation is by isolation and identification - requires X (Haematin) and V (NAD) factors, preferably in raised CO2 such as a candle jar. Serology: HI, DID, agglutination and IF have all been used but are not routine.

Differentiate from Mycoplasmosis, respiratory viruses, chronic or localised pasteurellosis and vitamin A deficiency.

3.TREATEMENT

Aasmus with nasal mucus discharge, swollen head is quite difficult to be cured. Use the following regimens:

Method 1: METHOCIN-TRI + ĐIỆN GIẢI-GLUCO K-C or MARPHASOL THẢO DƯỢC. As the guided dose, divide and mix for drinking 2times/day. Do not need to add any medicine