Life cycle and parasitic competence of Dermacentor nitens Neumann, 1897 (Acari: Ixodidae) on different animal species.

The objective of this study was to evaluate the life cycle and parasitic competence of Dermacentor nitens (Neumann, 1897) on different animal species. Experimental infestations were induced in five specimens each of seven species of possible hosts: rabbits, horses, sheep, cows, guinea pigs, birds and dogs. Rabbits were infested in the ear using artificial feeding chambers, and the horses, sheep, cows and dogs were infested in the ear without feeding chambers. For the infestation of guinea pigs, artificial feeding chambers were fixed on the back. Birds were infested by placing larvae on the back and under the wings without the use of chambers. All animals were inspected daily until the end of the parasitic phase (when the engorged females detached). The average period of engorgement was 25.1days on a horse, with larvae requiring 8days and nymphs 9days to reach engorgement; the average weight of engorged females was 271.4mg; the average weight of egg batches produced was 159.3mg, and the feed conversion rate was 56.8%. On rabbits, the average engorgement period was 27.6days, larvae and nymphs reached engorgement after 7.4 and 11days, respectively, the average weight of an engorged female was 108.4mg and the egg mass was 30.6mg. The feed conversion rate on rabbits was 30%. Cows, sheep, guinea pigs, dogs and birds were not competent hosts, since no engorged females were recovered. Rabbits, when artificially infested, can be used as an alternative host for the maintenance of these ticks in the laboratory. The parasitic specificity of D. nitens for horses was demonstrated in this study.