Carrapatos de animais silvestres e domésticos no Pantanal Sul Mato-grossense (sub-região da Nhecolândia): espécies, hospedeiros e infestações em áreas de manejos diferentes

Abstract

This research is a study about the tick fauna of Pantanal wetlands, MS, Brazil. Evaluation of cattle-raising on ticks populations, a detailed study on tick feeding on feral pigs and a list of ticks witch are reported in the study area are included. The cattle-raising impact was evaluated by trapping free-living ticks using a CO2 tick-trap. The traps were distributed in two areas: protected area, and the Nhumirim Ranch. Both areas are contiguous and locate at sub-region of Nhecolândia (18°59 S and 56°39 W), Pantanal of Mato Grosso do Sul state, Brazil. In each area, four habitat types were selected: cerrado (tropical savanna), forest patches, lakes and soda lakes. The last two are temporary lagoons of fresh and salted water, respectively. A total of 980 nymphs, 613 adults and 13 larvae of ticks of the genus Amblyomma were collected in 256 hours of collection. In a pen of calves infested by Ornithodoros rostratus 114 specimens were collected in just two hours including larvae, nymphs and adults. Adults of A. cajennense and A. parvum were more abundant in the savanna at Nhumirim Ranch, but did not differ among habitat types at protected area. There was a tendency of having more nymphs in Nhumirim Ranch than in protected area. The second conduced experiment was the comparison of the tick fauna of feral pigs at dry and wet seasons. A total of 44 feral pigs were examined and the species found were A. cajennense, A. parvum e O. rostratus. More adult ticks were collected in the dry season. Ecological and epidemiological aspects were discussed. Feral pigs are introduced specie and the role of this mammal on amplifying Amblyomma cajennense is clear. O. rostratus seems to be accidental parasite of feral pigs. The last part is a commented list of species including collected data and scientific literature. Up to day 18 tick s specie are reported on Pantanal wetlands including Argasidae (two) and Ixodidae (16) tick s species. The main genus was Amblyomma and the same species founded on wildlife are present on domestic animals and humans.