Helminths of Rattus spp. In Chile: effects on the helminthofauna of Abrothrix olivaceus.

LANDAETA-AQUEVEQUE, CARLOS A,; ROBLES, MARÍA DEL ROSARIO; CATTAN, PEDRO E.

Mendoza

Congreso; XX internacional Mammalogical Congress; 2009

Several studies have shown that exotic host species lose their parasites in processes of colonization of new environments. However, some parasites arrive to the new ecosystem with their host and then they colonize new hosts species. Rattus rattus and R. norvegicus are introduced species in Chile. They have colonized several environments in which they live together with the native rodent Abrothrix olivaceus.  In this work, the helminths of R. rattus and R. norvegicus from Chile central were studied with the aim of observing shared helminths taxa with A. olivaceus. Nine species of helminths were found in Rattus spp.: Aonchoteca sp., Aspiculuris tetraptera, Heterakis spumosa, Hymenolepis diminuta, Litomosoides sp., Nippostrongylus brasiliensis, Physaloptera sp., Pterygodermatites (Paucipectines) sp. and Syphacia muris. Rattus rattus was parasitized by all these species, but in R. norvegicus, A. tetraptera, Pterygodermatites sp. and Litomosoides sp. were not observed. Heterakis spumosa was previously found in A. olivaceus. This is the first record of helminthfauna of  Rattus spp. in central Chile, observing that these rodent species have been font of typical cosmopolitan helminths, as H. spumosa, for A. olivaceus. By the other hand, Physaloptera sp. and Pterygodermatites (Paucipectines) sp. could colonize Rattus spp. from native rodents. Therefore, these advances are the bases for future studies whose aim will be to check which factors affect the processes that act in the parasitic colonization of host species (e. g. role of intermediate hosts species), suggesting the more probable route direction between exotic and native hosts.