Avian mycobacteriosis in free-living raptors in Majorca Island, Spain

• Published in: Avian Pathology
• Main Authors: Millán, Javier, Negre, Nieves, Castellanos, Elena, De Juan, Lucia, Ana, Mateos, Parpal, Lluis, Aranaz, Alicia
• Other Authors: Govern Illes Balears, Wildlife Health and Control
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2010
• Subjects: Life Sciences; Falco peregrinus; peregrine falcon
• Online Access: https://hal.archives-ouvertes.fr/hal-00557317; https://hal.archives-ouvertes.fr/hal-00557317/document; https://hal.archives-ouvertes.fr/hal-00557317/file/PEER_stage2_10.1080%252F03079450903389945.pdf; https://doi.org/10.1080/03079450903389945

International audience Avian mycobacteriosis is a chronic, infectious disease caused by different species of mycobacteria, usually belonging to the Mycobacterium avium complex (MAC). From 2004 to 2007, 589 raptors brought dead or sick to a wildlife rehabilitation centre in Majorca (Balearic Islands, Spain) were necropsied. The birds belonged to 12 different species, chiefly common kestrel (Falco tinnunculus) (n=297), scops owl (Otus scops) (n=109), barn owl (Tyto alba) (n=75), long-eared owl (Asio otus) (n=58), peregrine falcon (Falco peregrinus) (n=27), and booted eagle (Hieraaetus pennatus) (n=13). Gross lesions compatible with mycobacteriosis were observed in 14 birds (2.4%) found in several locations in Majorca. They were 12 kestrels (prevalence in this species=4.0%), one long-eared owl (1.7%) and one scops owl (0.9%), all the birds presenting white-yellowish nodules from pinpoint size to 1 cm in diameter in diverse organs, mainly in liver, spleen and intestine. Affected organs were subjected to bacteriology and molecular identification by PCR and, in all the cases, infection with Mycobacterium avium subsp. avium was confirmed. The observed prevalences are similar to those previously observed in Holland, though the actual prevalence detected in this study is likely to be higher than reported because only birds with gross lesions were subjected to culture. Further molecular characterization with a set of six MIRU-VNTR loci was used to sub-typify the isolates in order to show the existence of possible epidemiological links. Six different genotypes were found, which points to infection from multiple focuses. No temporal or geographical aggregation of the cases was observed associated to the presence of positive birds or to the different VNTR allelic profiles. The most feasible origin might be water or food sources, though the reservoir of mycobacteria remains unknown.