Abstract

The Schubot Exotic Bird Health Laboratories have tested greater than 500 free-living non-Psittaciformes of more than 30 species (Table 1) for avian borna virus (ABV). Birds sampled include hunter-killed ducks; raptors and aquatic birds which died or were euthanatized during rehabilitation; birds which were culled by animal control authorities; Passeriformes which were collected for museum study; and rehabilitated pre-release ducks and pelicans from Wildlife Center of Texas. Samples tested include choanal and cloacal swabs, and brain, liver, and splenic tissues. Avian borna virus sequences were amplified using two multiplexed primer sets. One recognized matrix (M) protein genes and the other recognized conserved regions of the nucleoprotein (N) genes. Positive results were verified by repetition, sequencing, and culture confirmation of ABV positive animals. Many non-Psittaciformes species were identified with avian borna viruses, particularly within the Anseriformes and Charadriiformes. However, sample sizes in other avian taxa were low. An improved recovery rate for borna virus from the brain of birds occurred as compared with a very low recovery rate from testing as compared to swabs from choana, cloaca or eliminations. Clinical signs attributable to avian borna virus in psittacine birds such as gastrointestinal tract dysfunction and neurologic signs are seldom noted.^1-3 Sequencing has revealed multiple avian borna virus isolates which are not closely related to the isolate which appears most likely to cause clinical signs in Psittaciformes (ABV4).^3-5

Table 1. Non-Psittaciformes and sample type tested by Schubot Exotic Bird Health Laboratories for avian borna virus

^aRaptors included Falconiformes and Strigiformes
^bSwab from choana, cloaca, or eliminations
^cNon-brain tissues of kidney, liver, or spleen

Acknowledgments

The authors thank the curators of the Texas Cooperative Wildlife Collection, the Wildlife Center of Texas as well as the Schubot Exotic Bird Health Center for their support of this project.

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