Comparison of three template preparation methods for routine detection of beak and feather disease virus and avian polyomavirus with single and nested polymerase chain reaction in clinical specimens.

Direct comparisons are important when assessing the value of DNA extraction methods for diagnostic virology as the inhibitors present and the efficiency of extraction vary with the target infectious agent as well as the species and the site from which the clinical sample was obtained. Three DNA extraction methods were compared for routine polymerase chain reaction (PCR) detection of beak and feather disease virus (BFDV) in whole blood and feather samples and of avian polyomavirus (APV) in feather samples. Boiling in Chelex 100 Resin was found to be the most sensitive method for detection of BFDV or APV DNA in both feather and blood samples. In combination with nested PCR it enabled detection of BFDV DNA in 13/13 positive whole blood samples and in 22/23 positive feather samples. It also enabled detection of APV in 31/31 samples detected as positive in this study. NucleoSpin kits enabled detection of BFDV DNA in only 9/13 blood samples and in 18/23 feather samples. The lower rate of BFDV DNA detection when using NucleoSpin kits was not a result of inhibition of PCR in most cases. The NucleoSpin Tissue Kit enabled detection of APV DNA in 29/31 feather samples. Inhibition of DNA amplification was observed when using the DNAzol Direct kit. Therefore, of the methods evaluated here, Chelex 100 Resin treatment of samples was the best option for routine testing for BFDV and APV DNA in clinical samples.

Psittacine circovirus infection in parakeets of the genus Eunymphicus and treatment with beta-(1,3/1,6)-D-glucan.

Eight captive-bred horned parakeets (Eunymphicus cornutus) and four captive-bred Major Mitchell cockatoos (Cacatua leadbeateri) from the same aviary tested positive for psittacine circovirus (PsCV) DNA in whole blood by nested-polymerase chain reaction (PCR). The chronic form of disease with feather fragility and loss was observed in three horned parakeets. Infection in other individuals was subclinical. Immunosuppression, either hematologically or as susceptibility to secondary infections, was not observed. Treatment consisted of the administration of beta-(1,3/1,6)-D-glucan from oyster mushroom (Pleurotus ostreatus). Excluding two accidentally dead parakeets, four out of the original six horned parakeets, and all Major Mitchell cockatoos were negative for PsCV DNA in whole blood in 7-9 mo after the treatment was started. Even though the absence of PsCV DNA in blood does not signify elimination of the virus from the whole organism, these preliminary results indicate a possible effect of beta-glucan in the treatment of PsCV infection. To the author's knowledge, this is the first report of PsCV in horned parakeets.

Subalar cutaneous cysts with Harpirhynchus nidulans in bearded tits and hawfinches in Central Europe.

In wild bearded tits (Panurus biarmicus) and hawfinches (Coccothraustes coccothraustes) trapped in the Czech Republic and Slovakia from 1999 to 2003, characteristic yellow thin-walled subalar cutaneous cysts filled with friable material containing mites Harpirhynchus nidulans were found. The biggest cysts were 14 mm and 20 mm in size in bearded tits and in hawfinches, respectively. Histologically, the relatively thick wall of cysts contained erythrocytes (extravased or in small vessels) and heterophils; mononuclear cells were not found. The prevalences of subalar cysts in bearded tits at Nesyt (Czech Republic), Pusté Ul'any (Slovakia) and Parizské Mociare (Slovakia) were 6.1% (11 positive/180 examined), 12.7% (13/102) and 4.2% (4/96), respectively. The overall prevalence of subalar cutaneous cysts in bearded tits was 7.4% (28/378). The cutaneous cysts were found on adult birds only. Subalar cysts of H. nidulans in hawfinches were also found in four other locations in the Czech Republic and Slovakia.