Infectious Laryngotracheitis / Newcastle Disease / Infectious Bronchitis

Infectious Laryngotracheitis (ILT)

Causative Agent:Herpes Virus
This viral infection of poultry typically affects chickens only, although occasional reports suggest pheasants also may be susceptible.

Method of Spread The virus usually is spread through bird-to-bird contact, or contact with contaminated droppings or respiratory tract secretions. Recovered birds may be carriers and shedders of the virus, and may spread ILT to other poultry for many months.

Signs Sudden death of an individual bird is often the first sign. Blood-stained feathers around the head and neck may be observed. The disease spreads slowly through a flock, and mortality is high.

Treatment and Prevention Once the disease is diagnosed, there is no treatment for affected birds. Fortunately, an effective vaccine can be administered. Vaccination can prevent infection in uninfected birds during an outbreak, and can be given to prevent the disease in new stock.

Diagnosis usually is made by microscopic examination of the trachea by a veterinary pathologist.

Newcastle Disease

Causative Agent: Newcastle Disease Virus (NDV)
Newcastle virus is a virus that can infect most species of birds.

Method of Spread Sick birds shed the virus in respiratory secretions and fecal matter.

Signs In most instances the respiratory infection is quite mild in all but very young birds. However, egg layers usually show a moderate to severe egg production drop. It may take two to four weeks for egg production to come back to near normal levels.

Treatment and Prevention The commercial poultry industry practices widespread vaccination for this disease as a preventative tool. There is no effective treatment for this viral infection.

Infectious Bronchitis (IB)

Causative Agent: Corona Virus

Method of Spread
Infected birds shed the virus through respiratory secretions and feces. (This viral disease affects chickens only.)

Signs As with Newcastle disease, little or no death loss is common, except in very young chicks.

However, if sexually immature birds become infected, they may experience permanent damage to their reproductive tract and never lay eggs.

Mature layers infected with Infectious Bronchitis will lay eggs with misshapen, soft, wrinkled shells for several weeks. Broiler chickens will show poor weight gain and may develop secondary bacterial infections.

Infected birds usually cough, because of excessive mucus in their trachea. This disease spreads rapidly through the entire flock. In uncomplicated cases, the flock recovers quickly.

Treatment and Prevention There is no effective treatment. Prevention is by vaccination.

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