￼Prevalence of Psittacine Beak and Feather Disease Virus in captive psittacines in Northeast Spain
João Piçarra2 Ferran Bargalló1 Jordi Grífols1 David Perpiñan3
1 Zoològic Badalona Veterinaria. Conquista, 74. 08912 Badalona (Barcelona, Spain) 2 Clinica Veterinaria
Mercearia do Cão, R. dos Lirios no 1. 2750-246 Cascais (Portugal) 3 Naturavets, Balmes 17, 08918, Badalona (Barcelona, Spain)
Objetives of the Study:
The goal of this study was to establish the prevalence of the infection of Psittacine Beak and Feather Disease Virus (PBFDV) in captive Psittaciformes in Northeast Spain using polymerase chain reaction (PCR).
Materials and Methods:
A total of 1348 psittacine birds representing 83 different species were tested between December 2005 and June 2008. All birds were kept in the area of Barcelona (Northeast Spain) by breeders or private owners, and presented to the veterinary clinic for routine health checks or as a result of a medical problem. Blood samples preserved in ethylenediaminetetraacetic acid (EDTA) tubes were obtained and submitted for PBFDV PCR testing to an accredited laboratory.
In addition, clinical signs were studied in positive birds (n=26); those animals clinical status was classified as acute, chronic or asymptomatic (4). Haematology and biochemistry was performed in six symptomatic birds (positive to PBFDV).
Statistical analysis of data was performed with SPSS v.17 software; descriptive methods and Chi-square were used for the comparison of the differences of prevalence. The Win Episcope Version: 2.0 was used to test the representativity of the sample.
The sample was representative of the psittacine population of the Northeast Spain to a confidence level of 1%. The prevalence of infection with PBFDV was 2.60%±0.8.
The presence of PBFDV was detected in nine different species: Agapornis canus, Amazona albifrons, Amazona aestiva, Ara ararauna, Cacatua alba, Cacatua galerita triton, Eclectus roratus, Psittacus erithacus and Poicephalus senegalus. Some taxonomic groups revealed higher prevalence of infection - Eclectus roratus (8%), Agapornis sp. (6,7%), Ara sp. (3,33%) and Psittacus erithacus (2,89%), while in others no positive birds were found. Infection by PBFDV was recorded for the first time in asymptomatic Amazona albifrons and Agapornis canus.
New World species had a significantly lower prevalence of positive animals 1.22%±0.97, when compared to Old World species (3.39%±1.11; p=0,029). Most positive birds were young animals less than 3 years old (92%); however, most of the samples submitted for analysis were from immature animals.
Sixty-five percent of the positive birds were asymptomatic at the moment of the blood sample collection, including all New World birds.
Haematology was performed in 6 of the symptomatic animals and all showed anemia or leucopenia. Anemia was detected in 5 (83%) cases; leucopenia was detected in 5 (83%) cases and both anemia and leucopenia were detected in 4 (66%) cases.
The acute clinical presentation of PBFD was observed in Psittacus erithacus and Eclectus roratus (19% of all the positive birds). This acute presentation was always fatal.
The chronic clinical presentation was seen in Psittacus erithacus, Eclectus roratus and Cacatua alba, which represented 15% of the positive birds.
PBFDV infection may be more controlled in this Spanish region, compared to other European regions (1; 5) as a result of systematic health controls and viral DNA detection testing in pet psittacines, also due to a better control of the illegal traffic, or due to its geographic location in the Iberian Peninsula. It is possible that some positive cases have not been detected, especially in deathly acute situations or whenever the animal owner did not agree with performing the test.
The asymptomatic positive animals were relatively frequent and are considered to be affected individuals in incubation period, to be latent infected, to have eliminated the infection but still remain positive or to result from a sample collection or laboratory contamination (2; 3).
As stated before (6), the Old World psittacines species are more predisposed to infection and more susceptible to clinical disease.
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