Ranikhet disease

Newcastle Disease or Ranikhet disease is a highly contagious (Sudden, Severe and rapidly spreading) viral disease affecting poultry of all ages. Affected species include chickens, turkeys, pigeons and ducks. It causes production drops/fertility problems. The virus involved is Paramyxovirus PMV-1, which is of variable pathogenicity. Signs are typically of disease of the nervous, respiratory or reproductive systems. Morbidity is usually high and mortality varies 0-100%. Higher mortality is seen in Velogenic disease in unvaccinated stock.

Transmission is via aerosols, birds, fomites, visitors and imported psittacines (often asymptomatic). It is not usually vertical (but chicks may become infected in hatcheries from contaminated shells).

The virus survives for long periods at ambient temperature, especially in faeces and can persist in houses (in faeces, dust etc). for up to 12 months. However it is quite sensitive to disinfectants, fumigants and sunlight. It is inactivated by temperatures of 56°C for 3 hours or 60°C for 30 min, acid pH, formalin and phenol, and is ether sensitive.

Symptoms in affected birds are torticollis, opisthotonus and greenishdiarrhoea. Most typical lesion is pin point hemorrhages on the tips of proventricular gland, enlarged and hemorrhagic caecal tonsils. Disease can be prevented by Vaccination and Biosecuritypractices. Antimicrobials are required to control the secondary bacterial infections. Measures to boost the immune system of the birds will hasten the recovery.