ARS | Publication request: An initial evaluation of the pathogenesis of turkey-origin avian reovirus in poults

Submitted to: Poultry Science Association Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: April 1, 2007
Publication Date: July 9, 2007
Citation: Spackman, E., Day, J.M., Pantin Jackwood, M.J., Stephens, C.B. 2007. An initial evaluation of the pathogenesis of turkey-origin avian reovirus in poults [abstract]. Poultry Science Association Meeting. Abstract 65.

Technical Abstract: Enteric disease is known to cause poor performance in turkey flocks and, consequently, production losses in the industry. The pathogenesis of enteric viruses is not well understood and needs to be studied to further understand the nature of the disease. A virus isolated in 2003 from the intestines of poorly performing commercial turkeys in North Carolina (NC/SEP-R44/03) was selected for this study. Three-week-old Broad Breasted White turkeys were inoculated with NC/SEP-R44/03, and the sham inoculated birds were inoculated with sterile phosphate buffered saline. Both the sham inoculated birds and the infected birds were inoculated by oral gavage, and poults were weighed at days 0, 9, and 16 days post inoculation (DPI) to evaluate body weights. Ten sham birds and 10 inoculated birds were selected to study the cutaneous basophil hypersensitivity (CBH) response; a measure of T-cell response at 8 and 15 days PI. Another 20 birds were selected to study the antibody response by evaluating their response to Newcastle disease virus vaccine. Serum was collected from these birds at 21 and 42 DPI, and the antibody titers were determined by ELISA and were compared between the sham inoculated birds and the virus inoculated birds. Poults were periodically necropsied and examined for clinical signs of enteric disease. The spleen, bursa, and thymus were collected for histopathological analysis. Clear differences between the treatment groups in bodyweight, CBH response, and antibody response were not observed; however, gross lesions consistent with enteric disease were observed at 8 and 15 days PI. Gross lesions included gas-filled, water-filled intestines with undigested feed, and ceca with frothy contents. Enlarged bursas of fabricius with bursal “cores” were also observed.