Efforts of Telangana Animal Husbandry Department to determine cause of poultry mortality at a farm on the city’s outskirts is veering towards the dreaded Ranikhet disease. Interestingly, the disease has already been ruled out by another lab which also ruled out bird flu.
Earlier this month, the High Security Animal Diseases Lab (HSADL) in Bhopal received samples of 10 birds sent from a farm in Injapur of Hayatnagar mandal. The farm, which is just about 1.5 km away from another farm where avian influenza or bird flu killed thousands of birds last month, saw more than 10,000 birds die in a few days. Suspecting bird flu, Animal Husbandry Department sent samples to HSDAL which ruled out all types of bird flu and Ranikhet disease, which is also known as Newcastle disease.
“All the dead birds which were sent to us tested negative for all types of avian influenza and Newcastle virus,” said Dr. K.K. Kulkarni of the lab.
Both avian influenza and Ranikhet disease carry high mortality but the latter can be easily controlled even after infection. However, bird flu requires mass culling to control the outbreak and carries with it risk of infecting humans who come in close contact with infected birds.
While sharing its findings with the animal husbandry department, HSADL had also suggested that the department could consider sending more samples to test for avian influenza, given the high rate of mortality among the birds and its proximity to the site of last month’s bird flu outbreak.
However the animal husbandry’s Veterinary Biological and Research Institute (VBRI) began testing some of the birds and claimed to have found Newcastle virus, surprising even the owner of the farm.
“I had vaccinated the birds against the disease only last month. I was surprised when I was told that it is Ranikhet disease,” said B. Krishna Reddy, adding that he repeated vaccinations last weekend after receiving word from Animal Husbandry officials.
When asked about it, Dr. Kulkarni did not rule out the possibility of other samples at farm testing positive for Ranikhet, though he mentioned that it was surprising that the farm is seeing high mortality even after vaccination, and that too caused by a virus that can be easily controlled. He said that farmers usually do not check the quality of a live vaccine, which can cause disease if the virus in it has not been inactivated.
VBRI is set to continue testing until it can confirm a diagnosis and determine if Ranikhet disease was caused by ineffective vaccination.
