Bioactivity of Meliaceae, Amaryllidaceae, Solanaceae and Amaranthaceae plant aqueous extracts against the cattle tick Rhipicephalus microplus.

Commercial synthetic acaricides have selected resistant populations of Rhipicephalus microplus, and generate residues in the environment or in milk/cattle products. In this study, aqueous extracts (AE) from Melia azedarach (Maz), Allium sativum, Capsicum chinense, Nicotiana tabacum (Nta) and Dysphania ambrosioides were evaluated for the bioactivity against the cattle tick. The treatment using Nta or Maz AE resulted in the lowest egg hatching rate (34.0 ± 11% and 25.0 ± 19%), and in the values of reproduction inhibition ranging from 89.0% to 85.3%. Phytochemical screening associated to RP-HPLC/DAD analysis suggested the presence of alkaloids for Nta and gallic acid derivatives and catechins, for Maz. Such results highlighted that the use of Nta and Maz AE can be a promising source of bioactive compounds for the control of infections caused by the cattle tick.

Chemical composition and effect of Dysphania ambrosioides (L.) mosyakin & clemants essential oil on Biomphalaria tenagophila (D'Orbigny, 1835).

Dysphania ambrosioides (L.) Mosyakin & Clemants, known as santa maria herb, is a medicinal plant used on pest control and to treat parasitic diseases. Due to its potential for pest control, the aim of this work was to determine the chemical composition of D. ambrosioides essential oil and evaluate its molluscicidal effect on Biomphalaria tenagophila, which is an intermediate host for the Schistosoma mansoni trematode, that is responsible for causing human schistosomiasis. The essential oil extracted from its leaves showed 87% of (Z)-ascaridole and 100% of mortality against B. tenagophila at 10 ppm after 24 h of experiment. LC50 and LC90 values were, respectively, 2.40 (1.90-2.99) ppm and 8.75 (6.39-14.12) ppm. D. ambrosioides essential oil proved to be a promising natural molluscicide against schistosomiasis when compared with commercial products.

Chemical composition of various plant extracts and their in vitro efficacy in control of Fasciola hepatica eggs / Composição química de vários extratos vegetais e sua eficácia in vitro no controle de ovos de Fasciola hepática

ABSTRACT: Fasciolosis has been diagnosed in cattle, goats, sheep and horses in southern and southeastern Brazil. Effective alternative treatments are the targets of study. One promising alternative is the use of plant extracts. The aim of this study was to perform phytochemical analysis of extracts of Eugenia uniflora L., Harpagophytum procumbens, Psidium guajava L. and Stryphnodendron adstringens, and to evaluate the in vitro efficacy of these extracts on ovicidal activity in Fasciola hepatica. Plant extracts were analyzed for phytochemical properties. F. hepatica eggs were collected directly from the gallbladders of animals diagnosed as positive for fasciolosis on post mortem examination. One hundred eggs were incubated with 3 ml of each extract at concentrations of 0.10%, 0.25% and 0.50%, albendazole 0.50% (positive control) or tap water (negative control). To determine anti larval efficacy of each plant extract, hatched eggs were counted and the averages were used. Phytochemical analysis revealed the presence of phenolic compounds, tannins and terpenes in most extracts. E. uniflora L. extract was 100% effective at 0.10%, H. procumbens was effective at 0.25% and P. guajava L. and S. adstringens extracts were 100% effective at all concentrations tested. Taken together, the data suggested that ovicidal activity in F. hepatica is due to the presence of these bioactive compounds.

RESUMO: A fasciolose tem sido diagnosticada em bovinos, caprinos, ovinos e equinos no sul e sudeste do Brasil, sendo que tratamentos alternativos mais eficazes são alvos de estudo. Umas das alternativas promissoras é o uso de extratos vegetais no controle dessa e outras enfermidades. O objetivo deste estudo foi realizar a análise fitoquímica dos extratos de Eugenia uniflora L., Harpagophytum procumbens, Psidium guajava L. e Stryphnodendron adstringens, além de avaliar a eficácia in vitro desses extratos na atividade ovicida em Fasciola hepatica. Os extratos vegetais foram obtidos e analisados para determinação fitoquímica. Ovos de F. hepatica foram coletados diretamente das vesículas biliares de animais diagnosticados como positivos para fasciolose no exame post mortem. Cem ovos foram incubados com três mililitros de cada extrato nas concentrações de 0,10%, 0,25% e 0,50%, de albendazol a 0,50% (controle positivo) e água de torneira (controle negativo). Para determinar a eficácia de cada extrato vegetal os ovos eclodidos foram contados, e a média utilizada para os cálculos de eficácia. A análise fitoquímica revelou a presença de compostos fenólicos, taninos e terpenos na maioria dos extratos. O extrato de E. uniflora L. apresentou eficácia de 100% na concentração de 0,10%, o de H. procumbens a 0,25% e os extratos de P. guajava L. e S. adstringens apresentaram 100% de eficácia em todas as concentrações testadas. Assim, sugere-se que a atividade ovicida em F. hepatica seja devido à presença desses compostos bioativos.

Intestinal mucosa structure of broiler chickens infected experimentally with Eimeria tenella and treated with essential oil of oregano / Morfometria intestinal de frangos de corte infectados experimentalmente com Eimeria tenella e tratados com óleo essencial de orégano

In the first trial a total of 250 day-old male chicks were distributed into five treatments and given the following diets: a diet with growth promoter; a diet without added growth promoter; a diet added with avilamycin only; diet supplemented with 0.5g of oregano oil kg diet-1; 1.0g of oregano oil kg diet-1. In other trial a total of 288 day-old chicks was used and distributed into four treatments, which were given the following diets: a diet with anticoccidial agent; a diet without anticoccidial agent; a diet supplemented with 0.5g of oregano oil kg diet-1; a 1.0g of oregano oil kg diet-1. In the first trial the nonmedicated group had the highest crypt depth which differs from chickens fed with growth promoter or with 0.5 and 1.0g of oregano oil kg diet-1. The broilers fed with positive control (antibiotic and anticoccidial) had the highest villous: crypt ratio compared with the negative control that had the lowest villous:crypt ratio and the highest oocyst excretion in litter (P<0.05) In the second trial it was observed that broilers fed with non anticoccidial agent had the highest cecal lamina propria thickeness which differ from chickens fed with anticoccidial agent in diet or supplemented with 1.0 of oregano oil kg diet-1 (P<0.05).

Inicialmente, foram utilizados, neste estudo, 250 pintos de um dia de idade distribuídos em cinco tratamentos: dieta com promotor de crescimento; dieta sem promotor de crescimento; dieta contendo somente antibiótico; dieta com 0,5g de orégano óleo kg de ração-1 ou com 1,0g de orégano óleo kg de ração-1. No outro ensaio, foram utilizados 288 pintos de um dia de idade distribuídos em quatro grupos: dieta com anticoccidiano; dieta sem anticoccidiano; dieta com 0,5g de orégano óleo kg dieta-1 ou 1,0g de orégano óleo kg de ração-1. No primeiro ensaio, o grupo tratado sem promotor de crescimento apresentou a maior profundidade de cripta quando comparada com os animais tratados com promotor de crescimento ou com 0,5 e 1,0g de orégano óleo kg de ração-1. Os frangos que receberam a dieta com promotor de crescimento (antibiótico+anticoccidiano) apresentaram uma maior relação vilo:cripta em comparação com os frangos do controle negativo, os quais tiveram a menor relação vilo:cripta e uma maior excreção de oocistos por grama de fezes (P<0.05). No segundo ensaio, observou-se que os frangos alimentados com dieta sem anticoccidiano tiveram uma maior espessura de lâmina própria cecal, diferindo dos frangos tratados com anticoccidiano ou com 1,0 de orégano óleo kg de ração-1 (P <0,05).