Newcastle disease (ND), often called Ranikhet disease in India, is caused by a highly contagious virus that affects chickens and many other birds. Virulent strains can cause very high mortality in unvaccinated flocks, and even mild cases reduce growth and egg production.
Signs to watch for
Signs vary with the strain of virus and the immunity of the flock. Common ones include:
- Breathing problems — gasping, coughing, nasal discharge
- Greenish, watery droppings
- Nervous signs — twisted neck, circling, paralysis of legs or wings
- Swelling around the eyes and head
- Sudden drop in egg production; thin-shelled or misshapen eggs
- Sudden deaths, sometimes with few other signs
Several other diseases look similar, so confirmation by a veterinarian and laboratory is important.
How it spreads
- Contact with infected birds, including wild and village birds
- People, vehicles, crates, egg trays and feed bags moving between farms
- Contaminated water, feed and litter
- Through the air over short distances
Prevention
Vaccination is essential in India. Live vaccines (such as LaSota or B1 strains) are given by eye drop, drinking water or spray, and inactivated (oil) vaccines by injection, often in combination with other diseases. Breeders and layers usually need repeated doses through their life. Your schedule should be planned with your vet based on local disease pressure.
Biosecurity matters just as much: limit visitors, keep wild birds out of sheds, clean and disinfect equipment and vehicles, and never bring birds of unknown health status onto the farm.
If you suspect an outbreak
- Contact your veterinarian immediately and report to the local Animal Husbandry department as required.
- Stop all movement of birds, eggs, manure and equipment off the farm.
- Restrict visitors and keep staff on that farm.
- Dispose of dead birds safely — burial or burning, never in open fields or water.
Key points
- Highly contagious; can cause heavy losses
- Respiratory, digestive and nervous signs; sudden egg drop
- Vaccinate on schedule — boosters for long-lived birds
- Report suspected cases quickly