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Birds are an important component of the life histories and bioecology of a number of tick species and of some tick associated pathogens. An examination of the data concerning bird/tick associations in the Neotropics, showed that the tick Haemaphysalis leporispalustrisis (Packard, 1869) was rarely recorded infesting birds. The current study reports parasitism by H. leporispalustris in wild birds collected from Atlantic rain forest environments in the states of Rio de Janeiro (4LL) and Minas Gerais (17LL, 1NN), Brazil. All ticks were identified morphologically to the genus level; total DNA was extracted from each Haemaphysalis tick and examined by PCR and nucleotide sequencing of fragments of the eukaryotic genes encoding 16S rRNA and 12S rRNA. The bird species Arremon semitorquatus, Corythopis delalandi, Fluvicola nengeta, Troglodytes musculus, and Volatinia jacarina were recorded as hosts for H. leporispalustris for the first time in South America, and Turdus rufiventris represented a new record for Brazil. [ABSTRACT FROM AUTHOR]

This study aimed to identify the feeding habit ofPheidole radoszkowskiiMayr onRattus norvegicus(Berkenhout) carcasses, as well as whether its presence limits the occurrence of flies.Pheidole radoszkowskiiexhibited more necrophagous than predatory behaviour. Its abundance was inversely proportional to that of flies, confirming that this ant species may cause lesions in carcasses and its presence limits the occurrence of flies. This work clarifies the behaviour of an ant species often encountered on carcasses. [ABSTRACT FROM AUTHOR]

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The article offers information the "New reports of Acari ectoparasites on lizards of the genus Plica (Squamata: Tropiduridae) and a list of parasites known from this genus" by the authors, published within the issue. Topics include taxonomic study on the lizard genus while examining specimens that were parasitised by some ectoparasites, a chart depicting list of all literature records of parasites found in the genus Plica Gray, and the tick A. rotundatum and the trombiculid E. alfreddugesi.

The article focuses on a study conducted by authors related to plasmodium and haemoproteus infections in captive birds in Atlantic Forest, Brazil which reveals that infections were prevalent in captive birds.

The acaricidal activity of carvacrol, ( E)-cinnamaldehyde, trans-anethole, and linalool was studied on Rhipicephalus microplus and Dermacentor nitens larvae. All the substances were tested at concentrations of 2.5, 5.0, 10.0, 15.0, and 20.0 μl/ml, with 10 repetitions per treatment. The modified larval packet technique was employed in the tests and the mortality was evaluated after 24 h. In the groups treated with carvacrol, the lowest concentration (2.5 μl/ml) was sufficient to cause 100 % death of the R. microplus and D. nitens larvae. The same concentration of ( E)-cinnamaldehyde resulted in death of approximately 99 % of the larvae of both tick species and reached 100 % at the other concentrations. For trans-anethole, mortality rates above 90 % of the R. microplus and D. nitens larvae were only observed starting at the concentration of 15.0 μl/ml and reached 100 % at the highest concentration (20.0 μl/ml). Finally, the mortality rates of the groups treated with linalool were low, only reaching 8.4 and 14.5 % at the highest concentration (20.0 μl/ml) for larvae of D. nitens and R. microplus, respectively. These results show that carvacrol, ( E)-cinnamaldehyde, and trans-anethole have acaricidal activity, particularly carvacrol and ( E)-cinnamaldehyde, both of which resulted in high mortality rates for the larvae of these two tick species even at the lowest concentration. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the acaricidal activity of eugenol, with different solubilizations and concentrations, on Rhipicephalus microplus and Dermacentor nitens larvae and to determine the lethal time. The study consisted of four experiments, and the mortality was assessed using the larval packet test with adaptations. The mortality observed in the first experiment was 100 % for all the groups treated with eugenol solubilized in different solvents. In the second, the hydroethanolic formulation of eugenol was used, and the mortality rates for R. microplus and D. nitens was 100 % starting from the concentration of 5.0 μl/ml. In the third experiment, the mortality was 100 % for larvae of both R. microplus and D. nitens after 1 h of contact. And in the fourth experiment, the mortality was above 90 % and statistically similar ( p > 0.05) for the four methods the test evaluated. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this study was to assess the acaricidal activity of hydroethanolic formulations of thymol at varying concentrations on Rhipicephalus sanguineus and Dermacentor nitens larvae. The larval packet test was used and the thymol concentrations tested were 2.5, 5.0, 10.0, 15.0 and 20.0mg/ml. The control group was exposed only to water and ethanol (50/50%) and there were 10 repetitions for each treatment. The mortality was evaluated after 24h. For the R. sanguineus larvae, the mortality rates were 47.5, 50.2, 96.7, 95.9 and 98.1%, while for D. nitens the rates were 14.1, 75.0, 90.2, 90.3 and 99.5%, at respective thymol concentrations of 2.5, 5.0, 10.0, 15.0 and 20.0mg/ml. The results indicate that the hydroethanolic formulations of thymol tested have acaricidal activity on R. sanguineus and D. nitens larvae exposed topically, causing mortality greater than 90% 24h post-treatment starting at the concentration of 10mg/ml. [Copyright &y& Elsevier]

Graphical abstract Highlights • First report of the activity of thymol acetate on ticks • First report of the activity of eugenol acetate on ticks • The acetylation process did not enhance the activity against Rhipicephalus microplus • Carvacrol acetate was the acetylated derivatives with better activity on R. microplus • Carvacrol acetate provided a 100% mortality at the concentration of 5 mg/mL Abstract This study reports the comparative evaluation of the activity of carvacrol, thymol, eugenol and their respective acetylated derivatives (carvacrol acetate, thymol acetate and eugenol acetate) on Rhipicephalus microplus , to verify the possible influence of the acetate group. The acetylated derivatives were prepared from reactions of the phenolic compounds with acetic anhydride/pyridine. The formation of the products was confirmed by analysis of hydrogen and carbon-13 nuclear magnetic resonance (1H and 13C NMR) spectra. The larval packet test was used to evaluate the acaricidal activity, with concentrations of 0.312, 0.625, 1.25, 2.5, 5.0, 7.5, 10.0 and 15.0 mg/mL. Thymol and carvacrol resulted in 100% mortality starting at the concentration of 2.5 mg/mL, while the same was observed for carvacrol acetate starting at the concentration of 5.0 mg/mL. For the other treatments, 100% mortality was only achieved in the groups treated with the highest concentration (15.0 mg/mL). The LC 50 and LC 90 values (mg/mL) of carvacrol acetate (2.49, 4.21), thymol acetate (2.97, 8.52) and eugenol acetate (4.25, 13.10) were higher than those for the corresponding precursor molecules carvacrol (0.83, 2.02), thymol (1.26, 2.21) and eugenol (2.77, 5.35). The acetylation process did not enhance the activity of these substances on unengorged larvae of R. microplus, since the precursor substances (carvacrol, thymol and eugenol) had greater efficacy. [ABSTRACT FROM AUTHOR]

This study evaluated the acaricidal activity of the methanol extract of Acmella oleracea with 0.187% of spilanthol against immature stages of Amblyomma sculptum . The packet test was used to evaluate the extract’s activity on unengorged larvae and nymphs, testing concentrations of 0.4 to 50 mg/mL for larvae and 12.5 to 200.0 mg/mL for nymphs. For the engorged stages, the immersion test was used, at concentrations of 0.4 to 50 mg/mL for larvae and 12.5 to 200.0 mg/mL for nymphs. The methanol extract caused 100% mortality of the unengorged larvae and nymphs starting at concentrations of 12.5 and 200.0 mg/mL, respectively. For engorged larvae and nymphs, the mortality was 100% starting from concentrations of 12.5 and 150.0 mg/mL, respectively. The LC 50 for unengorged larvae was 3.2 mg/mL, while for engorged larvae it was 6.6 mg/mL. For unengorged nymphs, the LC 50 was 38.5 mg/mL, but it was not possible to calculate the corresponding value for engorged nymphs because the data did not fit the probit model. These results demonstrate that the methanol extract of A. oleracea has acaricidal activity against different immature stages of A. sculptum . [ABSTRACT FROM AUTHOR]

The acaricidal activity of combinations of thymol, carvacrol and eugenol was evaluated on larvae and engorged females of the cattle tick Rhipicephalus microplus. The first step assessed the compounds separately, in concentrations of 3.125, 6.25, 12.5 and 25 mg/mL. Then tests were performed with the compounds combined in the ratio of 1:1 at concentrations of 3.125 and 6.25 mg/mL, along with the control group treated with the solvent (3% DMSO). In the second step, combinations were tested incorporated in a formulation at the concentration de 6.25 mg/mL, using the larval packet and adult immersion tests. The associations carvacrol + thymol (3.125 mg/mL), carvacrol + eugenol and thymol + eugenol (6.25 mg/mL) presented synergism, while the other associations had an additive effect. In the experiments with formulation, all combinations caused 100% larval mortality, but the efficacy was under 15% against engorged females. Therefore, the combinations of thymol + carvacrol (3.125 mg/mL) as well as carvacrol + eugenol and eugenol + thymol (6.25 mg/mL) had a synergistic effect on engorged females, but when incorporated in the formulation, the acaricide activity was strong against larvae but weak against engorged females. Image 1 • The associations showed a synergistic effect on R. microplus females. • The formulated associations showed high activity on R. microplus larvae. • The formulated associations showed low activity on R. microplus females. [ABSTRACT FROM AUTHOR]