For a long time now, Charles Mutisya, a Kenya poultry farmer has had to grapple with large number of poultry deaths occasioned by New Castle disease
“Sometimes almost 95 per cent of the flock are wiped away by this disease. Vaccination is quite expensive though it reduces the deaths,” observes Mutisya.
Small scale poultry farmers across the East African region have to worry about this scourge that affects both the indeginous and exotic poultry breeds across all ecological zones.
Research conducted at the University of Nairobi shows that prevalence of Newcastle disease virus was significantly higher at 17.8 per cent in the dry hot zones compared to the cool wet zone-lower highlands- at 9.9 per cent showing evidence for climate as a risk factor in the occurrence in village chicken. With most of Kenya falling in this dry hot zone, new castle is serious problem to many farmers.
Effective vaccine
However, a ray of hope has now arrived with the information that the Kenya Agricultural Research Institute (Kari) in collaboration with Kenya Veterinary Vaccine Production Institute (Kevevapi) have adopted an effective vaccine, 1-2 ND against the disease.
The I-2 ND virus strain, is an avirulent Australian Newcastle Disease virus isolate from University of Queensland Australia, which is free of commercial ownership and is available to government vaccine production laboratories and other agencies in developing countries.
The vaccine is easy to administer through an eye-drop method using a dropper calibrated to deliver 0.1 ml dose of vaccine.
Vaccination should commence 14 days to one month before an anticipated outbreak of Newcastle disease with revaccinations every three months.
Studies
Validation studies were conducted in Busia, Mwingi, Naivasha, Mwea and Nyandarua under field conditions in free ranging indigenous chicken the vaccine was found to offer 62 per cent protection against Newcastle Disease.
According to Dr Ann Wachira, the Principal investigator of the Kasal Indigenous Chicken Project, the five districts were selected on the basis of indigenous chicken population, disease prevalence and lack of vaccination history six months prior to administering the vaccine. Selected sites represented the main agro-ecological zones.
The study revealed that less than five per cent of the indigenous chickens have protective antibodies against the causative virus.
"This shows that chicken in the study sites are highly susceptible to the virus," says Dr Wachira.
"However, after vaccination with a single dose of I-2 ND vaccine the protection level increased to 62 per cent."
by Mwangi Mumero
