Details of all parameters are available on Tables S1–S5 (Supplementary Data). Main differences are shown in Fig. 1, Fig. 2, Fig. 3, Fig. 4 and Fig. 5. Larva parameters ( Fig. 1): Larva yield of Brazilian ticks on guinea pigs was higher in relation to all others irrespective of tick origin or host (P < 0.05). Argentinian larva yield on this host was lower (P < 0.05) but still higher in relation to those from

canids and bovides (P < 0.05). At the same time Argentinian larval yield on cattle was the double in relation MDV3100 to Brazilian cohorts from the same host (P < 0.05) and similar to those from rabbits. Molting rate of Brazilian larvae engorged on cattle was slightly, nonetheless significantly (P < 0.05) lower than those engorged on other hosts irrespective of the tick origin (data not shown). Nymph parameters ( Fig. 2): On the whole nymphs engorged on guinea pigs were the heaviest and Brazilian ticks on this host were heavier than those from Argentina (P < 0.05). Molting rates of nymphs engorged on cattle from both tick populations were slightly but significantly (P < 0.05) lower in relation to ticks from other hosts (data not shown). Adult and reproductive parameters ( Fig. 3): No significant difference

was detected on most GDC-0449 clinical trial of the feeding and reproductive parameters of adult ticks between populations from Brazil and Argentina. Egg hatching rate of Brazilian ticks from rabbits was lower in relation to those of Argentinian ticks fed on dogs (P < 0.05) and both tick populations fed on cattle (P < 0.05). Host suitability for immatures (number of ticks produced): Irrespective of the origin of the tick, differences in biological performance varied greatly

among ticks fed on different hosts and such differences were, in many instances, stage specific ( Fig. 4). Thus, guinea pigs were the most suitable PAK6 hosts for A. parvum larvae of both populations as depicted by the higher number of nymphs obtained from larvae fed on this host species in relation to all other hosts (P < 0.05) ( Fig. 4A). Noticeably, fewer nymphs from the Brazilian population were obtained from larvae fed on bovines if compared to the Argentinian population (P < 0.05). A. parvum nymphs had a more uniform development on the various host species and although guinea pigs provided higher and canids and bovids lower number of adults from nymphs, differences were not significant (data not shown). Consequently the highest adult number (P < 0.05) obtained on guinea pigs assuming that both larvae and nymphs fed on this host ( Fig. 4B) was related to the highest number of larvae rather than nymphs obtained from this host species. Host suitability for adults ( Fig. 5): Best adult tick performance, measured by mean number of larvae obtained from one engorged female A. parvum tick, was achieved by females from the Brazilian population on dogs.