Reduction and sterilization of eggs of gastrointestinal nematodes in goats dewormed with benzimidazoles anthelmintics

Determinou-se a atividade ovicida "in vivo" e também a duração da mesma dos benzimidazóis: oxfendazole, fenbendazole, albendazole e thiabendazole em nematódeos gastrintestinais de caprinos. Cabras naturalmente infectadas com nematódeos gastrintestinais foram medicadas com oxfendazole (4,75 mg/kg),fenbendazole (5,0 mg/kg) e thiabendazole (44,0 mg/kg). Realizaram-se coletas de fezes diretamente da ampola retal para determinação do número de ovos por grama de fezes (OPG) e realização de coproculturas, antes do tratamento e em períodos subsequentes de três até doze horas após o tratamento. Posteriormente, as coletas passaram a ser realizadas com intervalos de 12 até 168 horas. O thiabendazole mostrou boa atividade na redução e esterilização de ovos de Strongyloides, ocorrendo o inverso com relação ao Haemonchus e Oesophagostomum. O oxfendazole, fenbendazole e albendazole apresentaram boa atividade na redução e esterilização de ovos de Trichostrongylus, não tendo a mesma atividade em Haemonchus e Strongyloides. O oxfendazole e o thiabendazole foram os únicos benzimidazóis que impediram o desenvolvimento e a multiplicação de fêmeas de Strongyloides de vida livre nas coproculturas dos animais vermifugados.The ovicide activity, “in vivo”, of the benzimidazoles: oxfendazole, fenbendazole, albendazole and thiabendazole on caprine gastrointestinal nematodes was determined and compared. Female goats naturally infected with gastrintestinal nematodes were medicated with oxfendazole (435 mg/kg), fenbendazole (5.0 mg/kg), albendazole (3.8 mg/kg) and thiabendazole (44.0 mg/kg). Feces were collected from the rectum to determine the number of eggs per gram (EPG) and to make fecal cultures, before medication and at subsequent periods from three to twelve hours after medication. Afterwards, collections were performed at intervals of 12 to 168 hours. Thiabendazole showed good activity on the reduction and sterilization of Strongyloides eggs but did not show the same activity against Haemonchus and Oesophagostomum. Oxfendazole, fenbendazole, and albendazole had good activity on the reduction and sterilization of the eggs of Trichostrongylus and Oesophagostomum, but did not have the same activity on Haemonchus and Strongyloides. Oxfendazole and thiabendazole were the only benzimidazoles that curbed the development and multiplication of the free living female Strongyloides in fecal cultures of dewormed animals

Seroprevalence of Toxoplasma gondii and Toxocara canis in a human rural population of Southern Rio Grande do Sul

Due to the growing population of pets, especially homeless dogs and cats, zoonoses still represent a significant public health problem. Toxoplasma gondii and Toxocara spp. are epidemiologically important zoonotic agents as they are etiological factors of human toxoplasmosis and toxocariasis, respectively. These parasites remain neglected even though they are substantially prevalent in rural areas. The aim of this study was to investigate T. gondii and T. canis seroprevalence and risk factors of seropositivity in a rural population in Pelotas municipality, Brazil. The study participants (n=344) were patients of a Basic Healthcare Unit (BHU) located in Cerrito Alegre. Blood samples were collected and tested for T. gondii antibodies by indirect immunofluorescence and T. canis antibodies by an indirect ELISA that targets an excreted-secreted antigen (TES). T. gondii seropositivity was 53.2%, with higher titers (1:256 - 1:1,024) in individuals who habitually eat pork, beef, or chicken, while T. canis seropositivity was 71.8% and concomitant T. gondii and T. canis seropositivity was 38.3%. Among the seropositivity risk factors assessed, only habitual undercooked meat consumption was significant (p = 0.046; OR = 3.7) for T. gondii and none of them were associated with T. canis seropositivity. Both parasites have a high prevalence in rural areas, which reinforces the need to invest in rural community education and health

Atividade in vitro do óleo essencial de Cuminum cyminum contra Haemonchus contortus de ovinos / In vitro activity of the essential oil of Cuminum cyminum against Haemonchus contortus of sheep

A maior dificuldade encontrada por criadores de ovinos é o controle dos nematódeos gastrintestinais, estes constituem uma das principais causas de perdas na produção. A utilização intensa, há décadas, de anti-helmínticos, induziu a instalação de resistência a praticamente todos os princípios ativos disponíveis. Existe a necessidade de novas propostas de controle, visando isto, o objetivo deste estudo foi avaliar o óleo essencial de Cuminum cyminum, in vitro, contra ovos, larvas de primeiro estágio e larvas de terceiro estágio de Haemonchus contortus, descrever os principais constituintes e a CI 50. O óleo foi extraído de sementes através do aparelho de clevenger e para determinar os principais constituintes foi realizada a cromatografia gasosa acoplada a espectrometria de massa. Os ovos e larvas foram obtidos através da coleta de fezes de ovinos infectados. Foram realizados os testes de inibição da eclosão de ovos, inibição da migração larval e inibição do desenvolvimento larval. As concentrações utilizadas do óleo foram: 9,4; 4,7; 2,35; 1,17; 0,58 mg/mL, todos os testes acompanhados de controle positivo anti-helmíntico comercial, controle negativo água destilada e controle com tween. Os resultados obtidos na maior concentração do óleo (9,4mg/mL) foram de 98,62% para inibição da eclosão, 69,12% para inibição do desenvolvimento e 23,45% para inibição da migração. Podemos concluir que o óleo essencial apresentou resultados promissores, que podem acrescentar futuramente no controle destes parasitos

Protective effect of the probiotic Lactobacillus acidophilus ATCC 4356 in BALB/c mice infected with Toxocara canis

Human toxocariasis consists of chronic tissue parasitosis that is difficult to treat and control. This study aimed to evaluate the action of the probiotic Lactobacillus acidophilus ATCC 4356 on larvae of Toxocara canis and the effect of IFN-γ cytokine on parasite-host in vivo (1.109 CFU) and in vitro (1.106, 1.107, 1.108, 1.109 CFU) interactions. Four groups of six BALB/c mice were formed: G1 - L. acidophilus supplementation and T. canis infection; G2 - T. canis infection; G3 - L. acidophilus supplementation; and G4 - PBS administration. Mice were intragastrically suplemented with probiotics for 15 days before inoculation and 48 h after inoculation with 100 T. canis eggs. The inoculation of T. canis was also perfomed intragastrically. The recovery of larvae took place through digestion of liver and lung tissues; the evaluation of IFN-γ gene transcription in leukocytes was performed by qPCR. The in vitro test consisted of incubating the probiotic with T. canis larvae. The supplementation of probiotics produced a reduction of 57.7% (p = 0.025) in the intensity of infection of T. canis larvae in mice, whereas in the in vitro test, there was no larvicidal effect. In addition, a decrease in the IFN-γ gene transcription was observed in both, T. canis-infected and uninfected mice, regardless of whether or not they received supplementation. The probiotic L. acidophilus ATCC 4356 reduced T. canis infection intensity in mice, however, the probiotic did not have a direct effect on larvae, demonstrating the need of interaction with the host for the beneficial effect of the probiotic to occur. Yet, the proinflammatory cytokine IFN-γ did not apparently contributed to the observed beneficial effect of probiotics

Origanum vulgare (Lamiaceae) OVICIDAL POTENTIAL ON GASTROINTESTINAL NEMATODES OF CATTLE

Due to anthelmintic resistance in nematodes, several research studies have been developed seeking control alternatives to these parasites. This study evaluated the in vitro action of Origanum vulgare on gastrointestinal nematode eggs of cattle. In order to evaluate the ability to inhibit egg hatch, different dried leaves extracts of this plant were tested, such as dye, hydroalcoholic and aqueous extracts at concentrations varying from 0.62 to 80 mg/mL. Each assay was accompanied by control containing levamisole hydrochloride (0.2 mg/mL), distilled water and 70 ºGL grain alcohol at the same concentration of the extracts. Test results showed that the different O. vulgare extracts inhibited egg hatch of cattle gastrointestinal nematodes at a percentage that varied from 8.8 to 100%; dye and hydroalcoholic extract were the most promising inhibitors. In view of this ovicidal property, O. vulgare may be an important source of viable antiparasitic compounds for nematodiosis control in ruminants