Activity of cumin essential oil to control fascioliasis: Efficacy and changes in the tegument of Fasciola hepatica.

Fasciola hepatica, the liver trematode, infects ruminants and causes economic loss. Because parasites are developing resistance to commercial drugs, the negative effects of parasitism are increasing. In this study, we aimed to evaluate the efficacy of cumin (Cuminum cyminum) essential oil against F. hepatica eggs and adults. The eggs were incubated with eight concentrations of the essential oil (0.031125-4.15 mg/mL), and viable eggs were counted after 14 days and classified as embryonated or non-embryonated. Adult flukes were incubated in Roswell Park Memorial Institute medium to ensure their viability and then incubated in essential oil. They were observed for 24 h after treatment. The adults were assessed with the two lowest effective oil concentrations used in the ovicidal test. Three controls were used for both tests: nitroxynil, a negative control, and Tween®80. After incubation in oil, the adult specimens were processed for histological analysis and stained with hematoxylin-eosin. In addition, the oil was tested for cytotoxicity using Madin-Darby bovine kidney cells to assess any possible effect on them. The oil was effective in ovicidal and adulticidal inhibition of the trematode, with statistically significant results. All concentrations assessed in the ovicidal test were 100% effective. The adult test was effective within 15 h and inactivated all the specimens at the highest concentration evaluated (0.06225 mg/mL). Histological analysis showed that cumin essential oil resulted in marked areas of vacuolization. The spines showed no structural changes but were surrounded by microvesicles. These findings indicated that cumin oil could be a potential compound in the control of fasciolosis.

Microscopic alterations in Fasciola hepatica treated with the essential oils of Pelargonium graveolens and Citrus aurantium.

Fasciolosis is one of the most important parasitic diseases in animal health, affecting mainly ruminants, causing economic and productivity losses. This study aimed to evaluate the in vitro ovicidal and adulticidal activity of essential oils (EOs) from Pelargonium graveolens (geranium) and Citrus aurantium (sour orange) on Fasciola hepatica. Performed Gas Chromatography of EOs P. graveolens and C. aurantium, with major compound, citronellol (31.37 %) and limonene (93.89 %), respectively. For the cytotoxicity assay, the sour orange EO showed to be promising when used in lower concentrations. For the ovicidal tests, the eggs were incubated with geranium EOs at concentrations from 4.5 to 0.03375 mg/mL and sour orange at concentrations from 4.25 to 0.031875 mg/mL, along with controls. The viable eggs were counted on the 14th day post-incubation. Adult forms of F. hepatica were incubated containing the EOs and observed for 24 h after treatment, as well as the control groups. Later the specimens were fixed for histological analysis. Geranium and sour orange EOs in trematode eggs at the concentrations tested were 100 % effective in inactivating hatching (p < 0.05) when compared to the untreated control. In the adulticidal test, the essential oil of P. graveolens at both concentrations tested (0.0675 and 0.03375) within 15 h, promoted the death of flukes. For C. aurantium, 18 h was enough to inactivate all specimens, up to a concentration of 0.06375. The histological analysis, observed the accumulation of liquid in the tegument in the specimens incubated in C. aurantium and P. graveolens, with vacuolization in the tegument and spines, preventing externalization. The results of the study present OEs with efficient ovicidal and adulticidal activity.

The relation between columbiform birds (Columba livia) age and gender and infection indices of rhinonyssid and ereynetid mites.

Respiratory systems of birds may be parasitized by rhinonyssid and ereynetid mites, which are commonly found in their nasal cavities. Levels of infection caused by mites in relation to maturity and gender of birds have been poorly investigated. Although Columba livia is the host of both Tinaminyssus and Trispeleognathus species worldwide, there are no data on prevalence and mean intensity of infection by mites in immature and adult males and females. Therefore, this study aims to analyze infections in relation to characteristics of hosts in southern Brazil. In the sample of 160 birds under study, 24.38% were parasitized by rhinonyssid mites (Tinaminyssus melloi and Tinaminyssus columbae) while 5.0% were infested with ereynetid ones (Trispeleognathus striatus). Infections by rhinonyssid mites in immature and adult birds, as well as in male and female ones, were similar and there were no significant differences in prevalence and mean intensity of infection. However, when infections were analyzed separately, prevalence of T. melloi was significantly higher in immature (19.77%) than in adult (6.76%) birds (p = 0.021). Ereynetid mites, which parasitized only males, were more prevalent in adult (9.46%) than in immature (1.16%) birds (p = 0.025). Reproductive and behavioral characteristics of C. livia (e.g., year-round breeding and social behavior) may enable transmission and maintenance of mite populations, since direct contact among hosts and the presence of mites in their nests are considered forms of transmission. Even though information on the life history of mites is important to understand parasite-host relations, there is a gap in the biology of species commonly found in C. livia, which constitutes an area to be explored.

An indirect ELISA for Neosporosis: Associating recombinant Neospora caninum proteins NcSRS2 and NcSAG1.

Neosporosis is caused by infection with the protozoa Neospora caninum. It manifests as various neurological symptoms and is considered as one of the main causes of abortion in cattle, and induces uncommon congenital infection in sheep. The standard diagnosis is based on indirect immunofluorescence (IFI); however, cross-reactivity with other protozoa proteins is common. Aiming a more specific diagnosis, recombinant antigens have been tested in several immunoassays; of these, NcSAG1 (surface antigen-1) and NcSRS2 (SAG1-related sequence 2) were the most promising. In this context, we developed an indirect ELISA with recombinant NcSRS2 (ELISA-rNcSRS2) and NcSAG1 (ELISA-rNcSAG1) proteins alone and in association (ELISA-rNcSRS2/rNcSAG1) for the diagnosis of cattle and ovine neosporosis. A total of 216 samples from cattle and 154 samples from sheep were used to evaluate the ELISAs. The sensitivity and specificity results of the ELISA-rNcSRS2 were 91.5 % and 96.4 % for cattle, and 89.6 % and 96.3 % for sheep, respectively. For the ELISA-rNcSAG1, the sensitivity and specificity were 84.9 % and 97.3 % for cattle, and 89.6 % and 92.6 % for sheep, respectively. The sensitivity and specificity of the ELISA-rNcSRS2/rNcSAG1 was 98.1 % and 99.1 % for cattle, 100 % and 97.2 % for sheep, respectively. These results indicated that indirect ELISA using the rNcSRS2 and rNcSAG1 proteins are a highly sensitive and specific method, especially when used in association, for detecting antibodies in cattle and ovine populations infected with N. caninum.

The raptor Chimango Caracara (Milvago chimango) (Aves: Falconiformes) - A new host for Trichomonas gallinae (protozoa: Trichomonadidae).

This work describes a specimen of Chimango Caracara (Milvago chimango - Vieillot, 1816), from southern Brazil, as a new natural host for Trichomonas gallinae (Rivolta, 1878). Caseous oral lesions were observed in a young bird, and the parasite was isolated in modified Diamond's media. Morphology of the parasite was evaluated through microscopy and subsequently, sequencing of the internal transcribed spacer 1 (ITS1) of ribosomal DNA was performed to confirm T. gallinae identification. As far as authors are concerned, this is the first report of Milvago chimango as a natural host for T. gallinae.

Aptima Trichomonas vaginalis assay elucidates significant underdiagnosis of trichomoniasis among women in Brazil according to an observational study.

OBJECTIVES: Trichomonas vaginalis (TV) infection is the most common non-viral STI globally and can result in adverse pregnancy outcomes and exacerbated HIV acquisition/transmission. Nucleic acid amplification tests (NAATs) are the most sensitive diagnostic tests, with high specificity, but TV NAATs are rarely used in Brazil. We investigated the TV prevalence and compared the performance of the US Food and Drug Association-cleared Aptima TV assay with microscopy (wet mount and Gram-stained) and culture for TV detection in women in Pelotas, Brazil in an observational study. METHODS: From August 2015 to December 2016, 499 consecutive asymptomatic and symptomatic sexually active women attending a Gynaecology and Obstetrics Outpatient Clinic were enrolled. Vaginal fluid and swab specimens were collected and wet mount microscopy, Gram-stained microscopy, culture and the Aptima TV assay performed. RESULTS: The median age of enrolled women was 36.5 years (range: 15-77). The majority were white, had a steady sexual partner and low levels of education. The TV detection rate was 4.2%, 2.4%, 1.2% and 0% using the Aptima TV assay, culture, wet mount microscopy and Gram-stained microscopy, respectively. The sensitivity of culture and wet mount microscopy was only 57.1% (95% CI 36.5 to 75.5) and 28.6% (95% CI 13.8 to 50.0), respectively. CONCLUSIONS: A 4.2% positivity rate of T. vaginalis was found among women in Pelotas, Brazil and the routine diagnostic test (wet mount microscopy) and culture had low sensitivities. More sensitive diagnostic tests (NAATs) and enhanced testing of symptomatic and asymptomatic at-risk women are crucial to mitigate the transmission of TV infection, TV-associated sequelae and enhanced HIV acquisition and transmission.

Characterization of Toxoplasma gondii isolates from herds of sheep in southern Brazil reveals the archetypal type II genotype and new non-archetypal genotypes.

Recent studies have demonstrated that, in Brazil and South America, strains of Toxoplasma gondii are often genotypically and biologically different from those found in countries on other continents. The objective of this study was to genotypically characterize T. gondii isolates from naturally infected sheep in herds in the southern region of the state of Rio Grande do Sul, Brazil, by means of the polymerase chain reaction with restriction fragment length polymorphism (PCR-RFLP). Five T. gondii isolates obtained from sheep in five municipalities in the state of Rio Grande do Sul were used. Application of multilocus PCR-RFLP multilocus using 12 genetic markers (SAG1, 5'3' SAG2, alt. SAG2, SAG3, BTUB, c22-8, c29-2, GRA6, L358, PK1, APICO and CS3) revealed four different genotypes in the five isolates studied: clonal type II (TgOvBrRS4), type BrIV (TgOvBrRS2 and TgOvBrRS3) and two new non-archetypal genotypes, ToxoDB-RFLP#270 and #271 (TgOvBrRS1 and TgOvBrRS5, respectively). The genotype structure found in the T. gondii isolates from naturally infected sheep in the southern region of Brazil was revealed to have high diversity. This study confirms the presence of rare circulation of the clonal type II genotype in Brazil.

Toxocara spp. seroprevalence in sheep from southern Brazil.

Visceral toxocariasis is a neglected parasitic zoonosis that occurs through the ingestion of embryonated Toxocara spp. eggs. A wide range of animal species can act as paratenic hosts for this ascarid. The main risk factor for humans is the ingestion of the eggs from contaminated soil; however, infection can also occur through the ingestion of contaminated raw or undercooked infected meat from paratenic hosts. The aim of this study was to verify the presence of Toxocara spp.-specific antibodies in sheep and to determine the risk factors associated with the infection of sheep in Rio Grande do Sul (a major sheep-producing and sheep-consuming state) in southern Brazil. Serum samples collected from 1,642 sheep were tested using an IgG enzyme-linked immunosorbent assay based on the excretory-secretory Toxocara canis antigen. Seroprevalence was 29.0% (477/1,642), and every farm included in the study contained at least one seropositive animal. These results indicate that T. canis infection is widely distributed among sheep herds in Rio Grande do Sul and that it represents a potential risk to human health.

[In vitro analysis of amitraz efficacy against Rhipicephalus (Boophilus) microplus (Canestrini, 1887) populations of southern region of Rio Grande do Sul state]. / Análise in vitro da eficácia do amitraz sobre populações de Rhipicephalus (Boophilus) microplus (Canestrini, 1887) da região sul do Rio Grande do Sul.

Commercial formulation of the amitraz is the most used acaricide in the southern region of Rio Grande do Sul State, however scientific data about the efficacy of these products in this region are sparse. The aim of the present study was to evaluate the frequency of R. (B.) microplus populations resistant to amitraz acaricides in the Southern region of Rio Grande do Sul State. So, the efficacies of five commercial products containing amitraz were compared. Results showed that the efficacy of amitraz acaricides was lower than 69% in 23% of studied populations. Nearly 29% of the tick samples showed an acaricide efficacy equal to zero, suggesting the presence of a high level of resistance to amitraz. Moreover, the most used commercial product in the region showed the lowest efficacy index. These results alert about the possible spreading of resistant on tick populations and justify research directed toward the search for alternative products to control this parasite.