Experimental Infection of Attwater's/Greater Prairie Chicken Hybrids with the Reticuloendotheliosis Virus

Department of Veterinary Pathobiology, Texas A&M University, College Station, TX 77843, USA.
Avian Diseases (Impact Factor: 1.24). 01/2007; 50(4):613-9. DOI: 10.1637/7517-021306R.1
Source: PubMed


Reticuloendotheliosis virus (REV), a common pathogen of poultry, has been associated with runting and neoplasia in an endangered subspecies of grouse, the Attwater's prairie chicken. The pathogenesis of REV infection was examined in experimentally infected prairie chickens. Three groups of four Attwater's/greater prairie chicken hybrids were infected intravenously with varying doses (tissue culture infective dose [TCID50], 200, 1000, and 5000) of a prairie chicken-isolated REV. A fourth group of four birds was not infected. Blood was collected prior to infection, and at various times up to 37 wk following infection. Peripheral blood mononuclear cells were examined for integrated proviral DNA by a single-amplification polymerase chain reaction (PCR) and nested PCR of a region within the pol gene. The nested PCR identified REV proviral DNA in all REV-inoculated birds by 2 wk postinfection and confirmed chronic infection throughout the study. With the exception of a bird that died from bacterial pneumonia 8 wk postinfection, neoplasia, resembling that seen in naturally occurring infections, was observed in all birds, even those receiving as little as 200 TCID50 of virus.

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    • "Because of their endangered status, the APC could not be used for experimental infection. Therefore, four adult APC/GPC hybrid birds, bred and housed in a BSL2 environment, were inoculated i.v. with TCID 50 5000 as previously described (Bohls et al., 2006a) with a prairie chicken REV isolate (R92) or with PBS alone in order to evaluate changes in lymphocyte populations following experimental infection. Four uninfected APC/GPC hybrids were used as controls. "
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