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Gastrointestinal Nematode Infection (GIN) are the main constraint to the production of small ruminants. Studies of medicinal plants have been an important alternative in the effort to control these parasites. Therefore, the purpose of this study was to evaluate the in vitro ovicidal and larvicidal activity of essential oil of Rosmarinus officinalis. The oil was extracted, analyzed by gas chromatography and tested on GIN eggs and larvae in six concentrations, 227.5mg/mL, 113.7mg/mL, 56.8mg/mL, 28.4mg/mL, 14.2mg/mL and 7.1mg/mL. To determine the ovicidal activity, GIN eggs were recovered from sheep feces and incubated for 48h with different concentrations of the oil. For the evaluation of larval migration, third-stage larvae (L3) were obtained by fecal culture, and associated with the essential oil for 24h at the same concentrations, after which they were left for another 24 hours on microsieves, followed by the count of migrating and non-migrating larvae. The assays of R. officinalis oil showed a significant (p<0.05) 97.4% to 100% inhibition of egg hatching and a significant (p<0.05) 20% to 74% inhibition of larval migration. The main constituent revealed by gas chromatography was Eucalyptol. The results indicate that R. officinalis essential oil has ovicidal and larvicidal activity on sheep GINs.

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vulnerability. The fact that these people share the environment with animals promotes the establishment of zoonotic parasitic infections, as well as the resultant parasitic cycles. Thus, parasites present in the environment must be identified, so that control measures can be recommended. In this context, this study’s objective was to evaluate environmental contamination by parasitic forms in a socially vulnerable community in southern Rio Grande do Sul. A total of 100 soil samples collected from the community were processed by a sodium dichromate centrifuge-flotation technique and analyzed by a compound microscope (40X objective) for the identification of parasite eggs, oocysts and cysts. All points were positive for two or more parasites, with the identification of 33.59% non-identified coccidian oocysts, Strongylida (25.4%), Ascaridida (21.31%), Trichuris spp. (8.19%), Toxocara spp. (3.27%), Amoebas (4.08%), Dioctophyma renale (2.45%), and Giardia spp. (1.63%). The presence of parasitic forms in all points analyzed surpasses other studies of environmental contamination carried out in the southern region of Brazil. In addition, the identification of several parasitic forms with zoonotic potential is concerning, since it shows the possibility of parasitic transmission to humans and other animals. In view of the results, the conclusion is that the environment analyzed is contaminated by parasitic forms, constituting a serious public health problem. Therefore, implementing educational and preventive measures in the community to control parasites is of crucial importance.

Dioctophyme renale is a zoonotic parasite with worldwide distribution, although its occurrence is little known. The objective here was to evaluate the presence of parasite eggs in the environment and in the urine of dogs and cats in an urban area. Soil samples and urine were evaluated respectively by means of the Caldwell-Caldwell technique and urinalysis. Out of the 100 soil samples, 3% presented D. renale eggs, and out of the 43 urine samples, 18.6% were positive, including the feline samples. Thus, D. renale eggs are present in the urban environment, and dogs and cats are parasitized by this nematode, which therefore represents a risk to public health.Keywords: Soil, urine, nematode, dog, cat, D. renale. ResumoDioctophyme renale é um parasito zoonótico com distribuição cosmopolita, entretanto sua ocorrência é pouco conhecida. Assim, o objetivo foi avaliar a presença de ovos do parasito no ambiente e na urina de cães e gatos de zona urbana. As amostras de solo e urina foram avaliadas, respectivamente, pela técnica de Caldwell e Caldwell e por urinálise. Das 100 amostras de solo, 3% apresentaram ovos de D. renale, e das 43 amostras de urina, 18,6% foram positivas, incluindo a de felino. Conclui-se que ovos de D. renale estão presentes no ambiente urbano, assim como os caninos e felinos apresentam-se parasitados, representando um risco para a saúde pública.

Gastrointestinal nematodes are responsible for great economic losses in sheep raising, and their control has long been carried out almost exclusively by the administration of anthelmintics, which have led to serious resistance problems. In the search for alternative control measures, phytotherapic research is highlighted. The aim of this study was to evaluate the action of Anethum graveolens (dill) essential oil on different stages of Haemonchus contortus life cycle, as well its cytotoxicity MDBK (Madin-Darby bovine kidney) cells. H. contortus larvae and eggs were obtained from infected sheep feces, and essential oil extracted from plant seeds through the Clevenger apparatus. 9.4, 4.7, 2.35, 1.17. 0.58 and 0.29 mg/mL concentrations were evaluated. The Egg Hatch Inhibition (HI), Larval Development Inhibition (LDI) and Larval Migration Inhibition (LMI) techniques were used. Thybendazole 0.025 mg/mL in HI and Levamisole 0.02 mg/mL in the LDI and LMI tests were used as positive controls, while distilled water and a Tween 80 solution were used as positive negative controls. The inhibition results obtained for the highest oil concentration were: HI 100%, LDI 98.58% and LMI 63.7%, differing ( <0.05) from negative controls. Main A. graveolens oil components present in 95.93% of the total oil were Dihydrocarvone (39.1%), Carvone (22.24%), D-Limonene (16.84%), Apiol (10.49%) and Trans-dihydrocarvone (7.26%). Minimum A. graveolens essential oil concentrations required to inhibit 50% (IC50) of egg hatching, larval development and larval migration were 0.006 mg/mL, 2.536 mg/mL and 3.963 mg/mL, respectively. Cell viability in MDBK (Madin-Darby bovine kidney) cells, when incubated with A. graveolens essential oil, was 86% for the highest (9.4 mg/mL) and 99% for the lowest concentration (0.29 mg/mL). A. graveolens essential oil, according to the results obtained in this study, is a promising alternative in sheep gastrointestinal nematode control. ResumoOs nematoides gastrintestinais são responsáveis por grandes perdas econômicas na ovinocultura, e seu controle tem sido realizado quase exclusivamente pela administração de anti-helmínticos, que levaram a sérios problemas de resistência. Na busca de medidas alternativas de controle, destaca-se a pesquisa fitoterápica. O objetivo deste trabalho foi avaliar a ação do óleo essencial de Anethum graveolens (endro) em diferentes estágios de Haemonchus contortus, bem como testar a viabilidade celular para o óleo. Larvas e ovos de H. contortus foram obtidos de fezes de ovinos infectados e óleo essencial extraído de sementes de plantas através do aparelho de Clevenger. As concentrações avaliadas foram 9,4, 4,7, 2,35, 1,17, 0,58 e 0,29 mg/mL. Verificou-se a Inibição de eclosão dos ovos (IE), Inibição de Desenvolvimento Larval (IDL) e Inibição de Migração Larval (IML). Tiabendazol 0,025 mg/mL em IE e Levamisole 0.02 mg/mL nos testes IDL e IML foram usados como controles positivos, enquanto água destilada e uma solução Tween 80 foram usados como controles negativos. Os resultados de inibição o...

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Studies aiming at the development and evaluation of alternative methods to minimise losses caused by the gastrointestinal nematode Haemonchus contortus are extremely important. Such research is essential, given the high morbidity rates among sheep and the significant mortality rates of lambs, allied to the low efficacy of commercial products for the control of this parasite. The purpose of this study was to evaluate the effect of the Saccharomyces cerevisiae (YT001 – YEASTECH) on the control of H. contortus and its modulation of the immune response in experimentally infected sheep. Eighteen sheep were divided into two groups. Group 1, the control group, comprised animals infected with H. contortus and supplemented with distilled water, while Group 2, the treated group, consisted of animals infected and supplemented with S. cerevisiae (400 million cfu/day of suspension for 49 days). The following parasitological parameters were evaluated: number of eggs per gram of faeces, number of infective larvae (L3) recovered per faecal culture, and parasitic load of the abomasum. The following immunological parameters were quantified: immunoglobulin (Ig)A in the mucous secretions and serum IgG; cytokines interleukin (IL)-4, IL-5 and IL-10; number of eosinophils in the abomasal mucosa and groups of cells positive for the markers: MHCII, CD4+CD25+, CD5+CD8+, WC4, CD5+CD4+, CD8+CD11b+ and CD5+WC1 by whole blood flow cytometry. The results revealed a significant decrease (P<0.05) in the number of larvae and significantly higher serum IgG levels (P<0.05) in the group supplemented with S. cerevisiae. The supplemented animals showed significantly larger numbers of eosinophils (P<0.05), as well as more cells positive for MHCII, CD4+CD25+, CD5+CD8+ than the control animals. This study confirmed the beneficial action of S. cerevisiae on the host immune response to H. contortus, as evidenced mainly by the smaller number of L3 recovered from the faeces of sheep supplemented with S. cerevisiae.