|DIMITROV, KIRIL - National Diagnostic And Research Veterinary Medicine Institute|
|ZARKOV, IVAN - Trakia University|
|DINEV, IVAN - Trakia University|
|GOUJGOULOVA, GABRIELA - National Diagnostic And Research Veterinary Medicine Institute|
Submitted to: International Symposium on Avian Influenza
Publication Type: Abstract Only
Publication Acceptance Date: 3/25/2015
Publication Date: 4/12/2015
Citation: Dimitrov, K.M., Zarkov, I., Dinev, I., Goujgoulova, G., Miller, P.J., Suarez, D.L. 2015. Histopathological characterization and shedding dynamics of LPAI H6N2 in Guinea fowls (Numida meleagris) infected experimentally [abstract]. 9th International Symposium on Avian Influenza. p. 84. Poster No. 55.
Technical Abstract: Guineafowl of different ages were inoculated intravenously with a H6N2 wild waterfowl-origin low-pathogenicity type A influenza virus. No evidence of clinical disease was observed. The examined infected birds had atrophy of the spleen, thymus, and bursa of Fabricius when compared to the non-infected control groups. The central and peripheral lymphoid tissues presented with either lymphoproliferative or degenerative lesions that increased in intensity from 14 to 21 days postinoculation (DPI). Lymphoid depletion was present in the bursa, thymic lobules, and T-dependant zone of the spleen’s Malpighi bodies. In contrast, lymphoid proliferation was observed in cecal tonsils, liver, lungs, and B-dependant zone of the spleen. Interstitial pneumonia was observed in the lungs of the birds at 14 and 21 DPI. The virus was recovered by virus isolation (VI) from both oropharyngeal and cloacal swabs with higher isolation rate from the latter. The birds from all of the experimental groups were shedding virus from 3 to 10 DPI with the highest rate at 7 DPI, and two birds from the two-month-old group were shedding the virus as long as 14 DPI. The recovery of the virus was successful from different organs until 14 DPI and also from two samples (kidney and spleen, one-year-old birds) at 21 DPI. Real-time reverse-transcriptase PCR was performed to detect viral RNA of avian influenza virus and the obtained results supported VI findings. These data indicate that the low-pathogenicity wild bird-origin influenza virus used in this study was pantropic during intravenous route of infection in guineafowl.