Panella et al. (1997) reported LC50/90 for (+)-terpinen-4-ol for I. scapularis. The concentrations resulting in 50% lethality (LC50) for R. (B.) microplus larvae ranged from 1.31 mg/mL (LGRA-201) to 4.34 mg/mL (LGRA-108), and the LC90 values ranged from 2.18 mg/mL (LGRA-201) to 6.02 mg/mL (LGRA-109) ( Table 3). These values demonstrate the high efficiency of the L. gracilis PI3K inhibitor essential oil for the control of

ticks along with the efficiency of their major components carvacrol (0.22 mg/mL) and thymol (3.86 mg/mL). The essential oil isolated from the LGRA-201 genotype proved to be the most lethal to tick larvae, with high mortality rates observed even at low concentrations. One possible explanation for this finding is the presence of carvacrol as major component and synergic effect with other monoterpenes, such as α-thujene, α-terpinene and γ-terpinene. Similarly, by investigating the effect of the essential oil of Lippia javanica in several

Boophilus subgenus, Madzimure et al. (2011) observed high efficiency of the essential oil in both larvae and adults. The observed patterns for lethal concentrations in engorged females were similar to those observed in larvae. However, LC50 for genotype LGRA-106 (4.66 mg/mL) and LC90 for genotype LGRA-201 (8.87 mg/mL) indicated higher efficacy relative to the other samples against engorged females (Table 3). With regard to the major components, carvacrol was found to have superior effect, with high lethality PFT�� molecular weight even at low concentrations. Similarly, Cetin et al. (2010) obtained LC50 of 3.18 mg/mL using pure carvacrol in adults of the Mediterranean tick Hyalomma marginatum. The use of natural products as acaricides may represent an important alternative for the control of animal parasites since

they are rich sources of bioactive compounds that are biodegradable, and potentially suitable for use as pesticides. The present findings demonstrate that L. gracilis essential oil may be used as a natural acaricide. Thymol and carvacrol are the major compounds in L. gracilis essential oil and may act synergistically to produce the acaricidal action against R. (B.) microplus observed. The authors wish to acknowledge CNPq, FAPITEC/SE and CAPES for supporting funds. “
“Trypanosoma theileri belongs to the however subgenus Megatrypanum. It was first described in cattle by Theiler, Laveran and Bruce in 1902 ( Hoare, 1972). This species is a cosmopolitan parasite of cattle and may occur with a high incidence. There is increasing evidence of immunosuppression involvement and association with a concomitant disease ( Doherty et al., 1993). However, its life cycle is not fully understood. The vectors are Tabanidae and Hyalomma anatolicum anatolicum. T. theileri in tabanids is typically characterized by stercorarian transmission ( Böse and Heister, 1993 and Latif et al., 2004). An experimental rodent model has not been established. The epimastigote and large trypomastigote forms can be revealed in peripheral blood. T.