INVESTIGADORES
BELDOMENICO pablo Martin
congresos y reuniones científicas
Título:
Philornis spp. causes significant mortality in thornbirds (Phacellodomus ruber) nestlings: experimental evidence
Autor/es:
MANZOLI, DE; BARENGO, E; ANTONIAZZI, LR; ARRABAL, JP; ROHRMANN, D; SARAVIA, MJ; SILVESTRI, L; BELDOMENICO, PM
Lugar:
Puerto Iguazú
Reunión:
Conferencia; LVII Annual International Conference of the Wildlife Disease Association; 2010
Institución organizadora:
Wildlife Disease Association
Resumen:
The Genus Philornis (Diptera: Muscidae) comprise a group of poorly known flies whose larvae
parasitize bird nestlings in the Neotropics. A negative impact on brood success has been
demonstrated for the semi-haematophagous Philornis downsi in Galapagos, but for the remaining
species of the Genus, mostly burrowing subcutaneous larvae, there is only documentation of negative
associations between parasitism and mortality, lacking experimental evidence that confirms causation.
The goal of this experiment was to dissect the specific impact of subcutaneous Philornis larvae on the
survival of nestlings of two of their preferred host species, Pitangus sulphuratus and Phacellodomus
ruber. To this aim we conducted a field experiment with a matched design, in which, within a brood,
one or more nestlings were randomly assigned to a daily larva removal treatment, from hatching to
fledging (or death). Their siblings served as matched controls and larva removal was mocked on
them. A total of 58 P. sulphuratus (25 treated and 33 controls) and 27 P.ruber (12 treated and 15
controls) were enrolled in the study. The data was analyzed with a Generalized Linear Mixer Model.
We found that nestlings of P.ruber that underwent larva removal had over 5 times the odds of
surviving than those of controls. On the other hand, we did not observe an effect of larva removal on
P.sulphuratus nestlings. This differential impact between host species highlight the complexity of
host-parasite relationships and warrant further research on these biological processes.