Increase in opportunistic pathogenic bacteria during a critical stage (fattening) of the annual cycle of a long-distance migratory bird￼
Jonathan Vergara Amado1,2,3 | Juan G. Navedo3 | Claudio Verdugo1
1.- Ecology and Evolution of Infectious Diseases Lab, Instituto de Patología Animal, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Valdivia, Chile. 2.- Programa de Doctorado en Ciencias mención Ecología y Evolución, Escuela de Graduados, Facultad de Ciencias, Universidad Austral de Chile, Valdivia, Chile. 3.- Bird Ecology Lab, Instituto de Ciencias Marinas y Limnológicas, Facultad de Ciencias, Universidad Austral de Chile, Valdivia, Chile.
Ponente: Jonathan Vergara, firstname.lastname@example.org
The annual cycle of a long-distance migratory bird includes different activities characterized by various physiological changes and demanding energy requirements. Migrants must perfectly balance their metabolism during physiologically contrasting stages (e.g., flight, pre-migratory fattening) of their annual cycle to fulfill this task. One of the key components in the regulation of physiological processes in any animal is their gut microbiota, since they provide metabolites that are used in different metabolic pathways within the host. However, to date there is still scarce literature showing the interaction between a long-distance migration and gut microbiota. We explored the composition and general functional profiles of the gut microbiota in Hudsonian godwit (Limosa haemastica), a shorebird that makes one of the longest transhemispheric migrations, through metabarcoding sequencing. Eight adult individuals were kept in captivity (AustralAvex, UACh) during two physiologically contrasting stages (maintenance and fattening) of the non-breeding season. DNA from fecal samples of each period were extracted and sequenced. Captive conditions allowed us to control variables (e.g., diet, water, temperature) that in nature are potent modulators of the gut microbiota. Our results reveal a significant effect of stages on alpha and beta diversity, specifically during the fattening period where phylogenetic diversity increases and community composition changes compared to maintenance. Also, some functional categories change significantly between the different stages, mainly increasing those related to amino acid metabolism during the fattening stage. Notably, within the main compositional changes, there is a considerable increase during fattening of two genera of bacteria known in the literature to be opportunistic pathogens, Psychrobacter and Corynebacterium. Therefore, the question remains whether these types of bacterial genera mentioned have antagonistic or beneficial functions in a critical stage of a long-distance migratory bird. Fondecyt N° 1191769, 1161224. ANID scholarship N° 21180753.