Scientists at the Department of Veterinary Microbiology, Kerala Veterinary and Animal Sciences University (KVASU), Mannuthy, have developed a vaccine for Riemerellosis, a bacterial disease that causes high mortality in ducks. Riemerellosis causes 5-75% mortality in ducks and more than 50% in ducklings below five weeks.
Duck plague and duck pasteurellosis used to be the two common diseases affecting ducks, against which routine vaccination is practised in the State. But it was noticed that many ducks died even after vaccination.
During the study, Priya P.M., Associate Professor, and team of the department isolated the causative agent, Riemerella anatipestifer, which causes Riemerellosis. Extensive research work has been carried out on the disease from 2010.
After reporting in Wayanad district in 2008, Riemerellosis, earlier known as new duck disease, was reported from different parts of the State. The disease led to huge losses to the duck farmers due to the high mortality of the birds even in March-April this year in Kuttanad and nearby places.
The Animal Husbandry Department sanctioned the project proposal on ‘Laboratory and field trials on oil adjuvant inactivated vaccines for the control of Riemerellosis’ during 2014-16. This was followed by two State- Plan funded projects in 2015-16 and 2016-17. An inactivated vaccine was developed in the Department of Veterinary Microbiology under the leadership of Dr. Priya.
No detailed study was done in the country before though Riemerellosis had been reported from various parts of the country. This was the first time that a vaccine had been developed for the disease in India, Dr. Priya said.
“The infected ducks show clinical signs of hurdling, squatting down, incoordination of neck, paralysis and death. Due to the similarity of illness, most often, Riemerellosis used to be misdiagnosed as pasteurellosis, a common bacterial disease of ducks. The antibiotic therapy for the affected ducks, which is costly, becomes ineffective once the organism reaches the brain. So, control of disease can be achieved only by vaccine,” she said.
Since there are 21 serotypes of Riemerella anatipestifer with little or no cross-protection, an ideal vaccine should be developed against serotype/serotypes present at that locality to provide broad-spectrum protection.
Minister for Animal Husbandry K. Raju recently released the vaccine to Animal Husbandry Department (AHD). Soon, the technology will be transferred to IAH&VB (Institute of Animal Health and Veterinary Biologicals), Palode. Technical assistance would be provided from the university for scale-up processes followed by field trials, Dr. Priya said.
