Javier A. Origlia¹ | Marina Winter² | Nancy Arias¹ | María Cecilia Netri¹ | Fernando A. Maydup¹ | Sergio D. Abate²

1. Catedra de Patología de Aves y Pilíferos, Facultad de Ciencias Veterinarias, Universidad Nacional de La Plata, Buenos Aires, Argentina; 2. Universidad Nacional de Río Negro, Sede Atlántica. Centro de Investigaciones y Transferencia de Río Negro (UNRN-CONICET). Viedma, Río Negro, Argentina.

Ponente: Javier A. Origlia, javieroriglia@yahoo.com

The Burrowing Parrots (Cyanoliseus patagonus) colony at Balneario El Cóndor (Patagonia, Argentina) is the largest colony of Psittaciformes in the world.  However, little is known about the pathogens that circulate among them. Chlamydia spp. and Psittacid Herpesvirus (PsHVs) have been found in wild and captive parrots and C. psittaci is considered endemic in many wild bird populations. So, the aim of this study was to detect the presence of Chlamydia spp. and PsHVs in Burrowing Parrots within the context of a mass mortality event between December 2020 and February 2021. Sixteen parrots were collected: 11 adults and 5 youngs. A necropsy was performed on each. Samples were taken for histopathology and trimucosal swabs for molecular studies. Detection of Chlamydia spp. was performed with a qPCR (23S rRNA). The positive samples were rechecked with two qPCR specific for Chlamydia psittaci (ompA) and Chlamydia avium (incA). Also, an endpoint PCR (ompA) were performed. For the detection of PsHVs a specific qPCR (UL16) and a semi-nested PCR (UL17/16) were performed. Chlamydia and PsHVs positive samples were sequenced. Five Burrowing Parrots were positive for Chlamydiaceae: four C. psittaci and one C. avium. One of the positive samples for C. psittaci was sequenced and characterized as genotype B. Six Burrowing Parrots were PsHVs positive, two characterized as PsHVs 1. Also, histological lesions compatible with PsHVs were observed in six Burrowing Parrots. C. psittaci and PsHVs have been identified as significant pathogens of parrots with possible negative impact on bird conservation, production and public health. These results report for the first time the presence of chlamydial agents and PsHVs in Burrowing Parrots from the largest colony in the world. Molecular studies on the organs and on more Burrowing Parrots will allow us to determine the role of the pathogens in the mortality event.