Detection of Avian bornavirus in multiple tissues of infected psittacine birds using real-time reverse transcription polymerase chain reaction

Abstract

Avian bornavirus (ABV), the cause of proventricular dilation disease in psittacine birds, has been detected in multiple tissues of infected birds using immunohistochemical staining (IHC) and reverse transcription polymerase chain reaction (RT-PCR). In the current study, real-time RT-PCR, using primers targeting the ABV matrix gene, was used to detect ABV in 146 tissues from 7 ABV-infected psittacine birds. Eighty-six percent of the samples tested positive, with crossing point values ranging from 13.82 to 37.82 and a mean of 22.3. These results were compared to the findings of a previous study using gel-based RT-PCR and IHC on the same samples. The agreement between the 2 RT-PCR techniques was 91%; when tests disagreed it was because samples were negative using gel-based RT-PCR but positive on real-time RT-PCR. Agreement with IHC was 77%; 16 out of 74 samples were negative using IHC but positive on real-time RT-PCR. The results suggest that real-time RT-PCR is a more sensitive technique than gel-based RT-PCR and IHC to detect ABV in tissues. The tissues that were ranked most frequently as having a high amount of viral RNA were proventriculus, kidney, colon, cerebrum, and cerebellum. Skeletal muscle, on the other hand, was found to have a consistently low amount of viral RNA.

Phylogenetic Analysis Supports Horizontal Transmission as a Driving Force of the Spread of Avian Bornaviruses

“…Intestine, lung and whole blood from this bird were positive by RT-PCR, whereas the liver tested negative. This is in congruence with the detection of comparably low viral loads in the livers of bornavirus-infected psittacines [ 5 , 42 ].…”

<p>Comparison Of Four Anti-Avian IgY Secondary Antibodies Used In Western Blot And Dot-Blot ELISA To Detect Avian Bornavirus Antibodies In Four Different Bird Species</p>

“…The use of anti-bird IgY secondary antibody in the Western blot worked well for Blue and gold macaw, Cockatiel, and Mallard plasmas, a result similar to that obtained in other studies using anti-bird IgY secondary antibody to detect ABV exposure. 9,11,20 However using the anti-bird IgY secondary antibody in the dot-blot ELISA, the Blue and gold macaw and Cockatiel samples had poor positive responses while the Mallard samples were strongly positive. Monk parakeet plasma was not assayed by Western blotting due to the limited plasma volume available.…”

“…[5][6][7][8] Sampling for histopathology and tissue immunoassays, especially of nervous tissues, is not practical in living birds, thus these tests are more commonly used in post-mortem diagnosis. Reverse transcriptase polymerase chain reaction (RT-PCR) can utilize less invasive samples such as feather follicles, feces/urine, and cloacal swabs, 5,7,[9][10][11][12][13] however sensitivity will vary due to intermittent viral shedding. [13][14][15] Immunologic testing comparing ABV specific antigens found that the viral nucleoprotein is immunodominant and hence the best antigen to use in a microtiter plate ELISA and in fluorescent antibody assays.…”

Aviair bornavirus en kliermaagdilatatiesyndroom bij psittaciformen

“…Bornavirussen zijn enkelstrengige RNA-virussen behorend tot de orde Mononegavirales waartoe eveneens het "borna disease virus" (BDV) behoort dat voornamelijk bij schapen, katten en paarden encefalitis veroorzaakt (Hoppes et al, 2010). ABV kan bij klinisch geïnfecteerde vogels in een groot aantal organen aangetroffen worden (Delnatte et al, 2014;Rinder et al, 2009); dit in tegenstelling tot BDV dat een tropisme voor het centrale en perifere zenuwstelsel vertoont (Berg et al, 2001;Ludwig et al, 1985;Malkinson et al, 1993). Er werden reeds 13 verschillende genotypes van het ABV aangetoond Honkavouri et al, 2008;Kistler et al, 2008;Rubbenstroth et al, 2012;.…”

“…RT-PCR voor de detectie van ABV kan uitgevoerd worden op urofecale stalen, vederstalen en op bloed (Delnatte et al, 2014;. Alhoewel viremie bij KDS meestal pas optreedt wanneer de aandoening reeds vergevorderd is, zou het testen van bloedstalen volgens sommige auteurs een goede sensitiviteit hebben Hoppes et al, 2013).…”