Investigations into feather abnormalities in racing pigeons

Abstract
The present study reports cases of feather abnormalities in young racing pigeons from four different lofts. The pigeons from the first three sources were characterized by among other things loss of feathers, stunted feathers, vane discoloration, feather dystrophy. In pigeons from the fourth loft, vanes were unevenly developed, while the shafts in wing feathers were narrow and had an hourglass appearance. Investigation revealed a history of pox, vaccination and deworming in some cases. Clinical, microbiological, parasitological examinations, hematology, PCR assays, necropsy and histopathology were performed. The presence of Eimeria spp., Trichomonas spp., and single Columbicola columbae were demonstrated. Pigeon circovirus (PiCV) DNA was confirmed in tissues and affected feathers of pigeons from the first three sources. Histopathology revealed the lymphoid depletion and the presence of the pathognomonic inclusion bodies in the bursa of Fabricius. In the fourth loft, a paramyxovirus infection (APMV-1) was confirmed by RT-PCR. The microscopic lesions in the feathers were similar, despite their different macroscopic appearance compared to previous cases. It seems that feather abnormalities may be the effect of a combination of several factors (infectious and non-infectious).