Caracterização da diversidade parasitária em carníveros silvestres e implicações na conservação

Recolher dados para actualizar os conhecimento da diversidade parasitária dos mesocarnívoros mais abundantes nas regiões do sul de Portugal e relacionar a dispersão parasitária, a conservação e a saúde humana constituíram os principais objetivos deste estudo. Raposas (Vulpes vulpes), sacarrabos (Herpestes ichneumon), fuinhas (Martes foina), ginetes (Genetta genetta) e texugos (Meles meles) atropelados foram os carnívoros-hospedeiros em estudo. Um grupo de raposas caçadas foi também considerado parte da amostra. A informação geo-referenciada de todos os animais serviu para executar a análise espacial. Realizaram-se necrópsias meticulosas e procedeu­ se à recolha, identificação e preservação dos parasitas encontrados. Pela primeira vez em Portugal é registada a presença do parasita da gineta Ancytostoma martinezi. A correlação entre os factores humanos e ambientais e, a riqueza de espécies foi determinada estatisticamente. Densidade populacional, disponibilidade de égua, tipo de uso de solo e distância mínima às sedes de concelho não apresentaram uma relação estatisticamente significativa com a infecção parasitária das raposas. Os resultados obtidos relativamente à presença de parasitas zoonóticos nos animais silvestres em estudo fomentam o trabalho multidisciplinar entre a Biologia da Conservação e as ciências médicas. ABSTRACT; The aim of this study was to collect data in order to update the information related to the parasitic diversity of the predominant mesocarnívores in the southern regions of Portugal and to establish relationships between the parasite dispersal, conservation and human health. Road killed foxes (Vulpes vulpes), mongoose (Herpestes ichneumon), stone marten (Martes foina), common genets (Genetta genetta) and euroasian badgers (Meles meles) were the considered carnivore-hosts. A sample of hunted foxes was also regarded.AD the animals had geo-reference information, ultimately used for spatial analysis. Thorough necropsies were performed and macroparasites collected, identified and preserved. For the first time in Portugal Ancylostoma martinezi, a common genets parasite.is recorded. Statistical species richness and correlation between human and environmental factors were determined. Human population density, water drainage, soil use, minimum distance to head council cities and the infection status of foxes proved no significant statistical relation. Results obtained on zoonotic parasites present in wild animals enhance the necessity of multidisciplinary work between Biology conservation and medical sciences.

Predictors of red fox (Vulpes vulpes) helminth parasite diversity in the provinces of Spain

We analysed the viscera of 321 red foxes collected over the last 30 years in 34 of the 47 provinces of peninsular Spain, and identified their helminth parasites. We measured parasite diversity in each sampled province using four diversity indices: Species richness, Marg a l e f’s species richness index, Shannon’s species diversity index, and inverse Simpson’s index. In order to find geographical, environmental, and/or human-related predictors of fox parasite diversity, we recorded 45 variables related to topography, climate, lithology, habitat heterogeneity, land use, spatial situation, human activity, sampling effort, and fox presence probability (obtained after environmental modelling of fox distribution). We then performed a stepwise linear regression of each diversity index on these variables, to find a minimal subset of statistically significant variables that account for the variation in each diversity index. We found that most parasite diversity indices increase with the mean distance to urban centres, or in other words, foxes in more rural provinces have a more diverse helminth fauna. Sampling effort and fox presence probability (probably related to fox density) also appeared as conditioning variables for some indices, as well as soil permeability (related with water availability). We then extrapolated the models to predict these fox parasite diversity indices in non-sampled provinces and have a view of their geographical trends.