Prevalência e consequências da infecção por Plasmodium tropiduri tropiduri em duas populações de calangos (Tropiduridae: Tropidurus torquatus) no estado de Minas Gerais, Brasil.

Abstract

A wide ranges of biotic and abiotic variables influence parasitic infection patterns. Therefore, each parasite-host system carries its own particularities and the consequences of infection vary from one parasite-host system to another. Thus, research on these systems are important for understanding the evolution of parasitism as the evolutionary relationships between host and parasite species. Plasmodium spp. Infections in lizard hosts shows a great variation in its patterns which depends on multiple environmental and host individual factors. However, available data in this field are scarce. In this work, we focused on Plasmodium tropiduri tropiduri infecting Tropidurus torquatus in two populations. Our objectives were first; assess infection patterns in terms of variation in prevalence, infection intensity and how these parameters vary with other parasite infections. Second, evaluate the malarial infection consequences on hosts by measuring parameters as body condition, predation risk, hematological alterations and concomitant consequences with other infections. We found three parasitic infections on T. torquatus, P.t. tropiduri, a microfilariae infection (Onchocercidae sp.) and an ectoparasitic species (Eutrombicula sp.). Spatial (locality) and temporal (season) variables, host individual characters like age and co-infections (microfilariae) defined P.t. tropiduri infection pattern. On the other hand, malarial infection was not related to alterations on H.L ratio, body condition and risk predation parameters, showing no effects on host fitness. Nevertheless, lizards with malaria showed hematological alterations associated to anemia and immune response. Concomitant effect with other infections were not evident but a possible facilitating effect for P. t. tropiduri by microfilariae was detected. In conclusion, variation in patterns of infections could depend on several abiotic factors and biological processes, such as co-occurrence of infections, in this case, with microfilaria. Although P. tropiduri does not seem to produce several negative consequences on T. torquatus, infected hosts present hematological changes that may determine costs and therefore can alter life and ecology of lizards.