P465 Aspergillosis in free-ranging Magellanic penguins

Abstract

Poster session 3, September 23, 2022, 12:30 PM - 1:30 PMAspergillosis is an opportunistic fungal disease caused by the Aspergillus genus, mostly by Aspergillus section Fumigati. Captive Magellanic penguins are vulnerable to Aspergillus infection, being this mycosis a limiting factor during the process of rehabilitation with a mortality rate of around 50%.ObjectivesGiving the scarce data regarding the occurrence of aspergillosis in non-captive penguins, we aimed to evaluate the proportional mortality by aspergillosis in free-ranging Magellanic penguins during their migration and reproductive season.MethodsCarcasses of Magellanic penguins were collected from the Southern coast of Brazil between June 2017 and October 2019 between Barra do Chui beach (Southern RS, Brazil - 33°44'19.9‘S 53°21'56.3’W) and the isthmus with the Lagoa do Peixe (Southern RS, Brazil - 31°26' S, 51°10' W 31°14'S, 50°54'W). In addition, in January 2019, penguins found dead in the reproducing colony in four islands localized in Puerto Deseado City (Santa Cruz, Patagonian, Argentina - 47°45′00″S 65°55′00″W) were collected. All animals were necropsied, and macroscopic alterations were observed. Samples of macroscopic lesions and/or respiratory systems were collected for histopathology and mycological culture. Only proven aspergillosis cases, defined by suggestive lesions at necropsy, associated with hyaline, septate, and 45° branched hyphae in histopathological slides and isolation of Aspergillus sp. in the culture were computed. Fungal isolates were identified by molecular techniques.ResultsA total of 98 Magellanic penguins were included in our study, being 80 recovered on the Southern RS beach, and 18 from the Patagonian colony. Two penguins collected in Southern Brazil were diagnosed with aspergillosis, both juveniles, one showing nodules in the lung parenchyma, and the other nodules and fungal colonies at the lung and air sac, resulting in a proportionate mortality rate of 2.5%. Both isolates were identified as A. fumigatus sensu stricto. Regarding the carcasses collected from the reproductive colony (Patagonian islands), no penguin had anatomopathological or mycological evidence of aspergillosis.ConclusionGiven the already known importance of aspergillosis in seabirds undergoing rehabilitation, these data suggest that penguins may already arrive in these centers infected by Aspergillus spp. The absence of aspergillosis cases in the reproductive period could be attributed to the low number of carcasses included. Our study is an initial step to demonstrate aspergillosis as one of the causes of mortality also in free-living penguins, especially during the migration process, instigating more studies, in other routes of migration, as well as in reproductive colonies.