DefinePK

Abstract

Newcastle disease virus (NDV) is always circulating in the pigeon flocks through reservoir birds that look more like healthy pigeons being maintained in the lofts. In Kanyakumari district, seroprevalence of NDV was found in all the months of the year 2015, which was found to be high during the monsoon seasons and low during the summer. During the southwest monsoon (May-July) 17.9±5.8% of birds had titer of 21 -23 while 14.6±4.0% of birds had titer of 24 – 27, during the northeast monsoon (Sep-Nov) 12.5±8.8% of birds had titer of 21 -23 while 8.7±3.70% of birds had titer of 24 – 27, and in the summer months10.0±3.4% of birds had titer of 21 -23 while the remaining 6.7±3.2% of birds had titer of 24 – 27. The NDV affected pigeons showed reduced level of PCV, RBC and haemoglobin, and elevated level of TLC, heterophils, basophils, eosinophils, monocytes and lymphocytes compared to normal healthy pigeons. HI titer value of NDV-seropositive pigeons ranged between log21 and log27 in unvaccinated flocks. The HI titer below log24 indicates that the suspected bird is a reservoir of NDV and the titers above that denotes that the suspected bird has enough protective antibodies against the NDV. If pigeons negative for anti-NDV antibodies are chosen and purchased for keeping farms, there would be least chance for the entry of a carrier bird into a farm. This study recommends that pigeon keepers should subject the birds to HI titer assay before purchasing from or selling to other growers to prevent the spreading of NDV through infected birds that look like healthy birds.