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The aim of the present study was to evaluate the insecticidal effect of the cassia, thyme and oregano volatile oils against the immature and adult flea’s stages. For this purpose, the tested samples were chemically characterized by GC-FID and GC-MS. The mortality of larvae and adult fleas, eggs, and pupae of Ctenocephalides felis felis was performed through in vitro tests at different concentration levels. Inhibition of development and residual efficacy were also determined. The chemical characterization of the cassia, thyme, and oregano volatile oils presented cinnamaldehyde (91%), thymol (44.7%), and carvacrol (76.2%), respectively, as major constituents. In general, the samples showed insecticidal activity for both immature and adult flea’s stages. The best LC50 values for adults were obtained by oregano volatile oils (33.5 and 21.8 μg·cm−2, respectively, 24 and 48 h). Cassia volatile oils showed the best results against larvae (17.2 and 10.3 μg·cm−2, respectively, 24 and 48 h), eggs (3 μg.cm−2), and pupae (34.6 μg·cm−2), as well as the lowest value for inhibition of development (2.3 μg·cm−2). The oregano and thyme volatile oils showed residual efficacy greater than 80% for 6 days while cassia showed this result for 4 days. The results demonstrated the potential of volatile oils for flea control in all stages of the life cycle, with emphasis on cassia. The residual effects of the volatile oils are promising for the development of new and environmentally friendly phyto-pesticides for veterinary uses.

Essential oils (EOs) are considered a new class of ecological products aimed at the control of insects for industrial and domestic use; however, there still is a lack of studies involving the control of fleas. Ctenocephalides felis felis, the most observed parasite in dogs and cats, is associated with several diseases. The aim of this study was to evaluate the in vitro activity, the establishment of LC50 and toxicity of EOs from Alpinia zerumbet (Pers.) B. L. Burtt & R. M. Sm, Cinnamomum spp., Laurus nobilis L., Mentha spicata L., Ocimum gratissimum L. and Cymbopogon nardus (L.) Rendle against immature stages and adults of C. felis felis. Bioassay results suggest that the method of evaluation was able to perform a pre-screening of the activity of several EOs, including the discriminatory evaluation of flea stages by their LC50. Ocimum gratissimum EO was the most effective in the in vitro assays against all flea stages, presenting adulticide (LC50 = 5.85 μg cm−2), ovicidal (LC50 = 1.79 μg cm−2) and larvicidal (LC50 = 1.21 μg cm−2) mortality at low doses. It also presented an excellent profile in a toxicological eukaryotic model. These findings may support studies involving the development of non-toxic products for the control of fleas in dogs and cats.

As infestações por Rhiphicephalus microplus causam perdas significativas na bovinocultura brasileira provocando diversos prejuízos como, perda de peso e baixa conversão alimentar, podendo comprometer a produção de carne e leite. O extrato de plantas é utilizado como uma forma alternativa para o controle de carrapatos, visto que o uso indiscriminado de acaricidas está gerando populações de carrapatos cada vez mais resistentes. Assim, em conformidade com o exposto, o presente trabalho objetivou testar a eficiência reprodutiva in vitro de ativos extraídos em solvente apolar (hexano) da planta Artemisia vulgaris sobre o carrapato Rhipicephalus microplus. Inicialmente, para a avaliação das eficácias in vitro dos extratos da A. vulgaris, foram utilizadas teleóginas da colônia de R. microplus do Laboratório de Quimioterapia Experimental em Parasitologia Veterinária da UFRRJ (LQEPV), sendo separadas em grupos de 10 e submetidas ao teste de imersão em hexano na concentração de 1250 ppm, bem como controle positivo e negativo. A leitura do percentual de eclodibilidade que foi realizada para o cálculo da Eficiência Reprodutiva do Produto, foi feita através de análise de variância. Deste modo, ainda que hajam poucos trabalhos que comprovem a eficácia de A. vulgaris como um biocarrapaticida, pôde-se concluir com o presente estudo que, quando esta foi extraída em hexano demonstrou uma boa eficácia no controle in vitro de R. microplus.

The aim of this study was to evaluate the in vitro activity of Syzygium aromaticum essential oil (SAEO) and its main constituent eugenol (EG) against adult fleas and their action in the maturation of eggs into adults of Ctenocephalides felis felis. In order to evaluate the pulicidal activity, 10 adult fleas were exposed to a filter paper impregnated with SAEO and EG at increasing concentrations of 0.047; 0.094; 0.188; 0.375; 0.750; 1.50; 3.00; 6.00; 12.00 and 24.00 μg cm−2. Flea mortality was evaluated 24 and 48 h after exposure. In order to evaluate the inhibition of the maturation of eggs into adults, 10 eggs were exposed to filter paper impregnated with SAEO and EG at the same concentrations used in the pulicidal test, and the evaluation was performed 30 days after incubation. Untreated repetitions were maintained in both studies (control group). The lethal concentration 50 (LC50) of pulicidal activity to SAEO was 5.70 μg cm−2 in 24 h and 3.91 μg cm−2 in 48 h. The LC90 was 16.10 μg cm−2 and 15.80 μg cm−2 in 24 and 48 h, respectively. The LC50 of inhibition of the maturation of eggs into adults was 0.30 μg cm−2 and the LC90 3.44 μg cm−2. The LC50 of pulicidal activity to EG was 2.40 μg cm−2 in 24 h and 1.40 μg cm−2 in 48 h; the LC90 was 8.10 μg cm−2 and 3.70 μg cm−2 in 24 h and 48 h, respectively. The LC50 of inhibition of the maturation of eggs into adults was 0.10 μg cm−2 and the LC90 0.68 μg cm−2. Based on the results obtained, it is possible to conclude that the both SAEO and EG have in vitro pulicidal activity as well as acting as inhibitors of the maturation of eggs into adults of the flea C. felis felis.

Plant extracts and essential oils have been showing potential for use as acaricides. Rhipicephalus sanguineus, the brown tick, mainly parasitizes dogs and is responsible for pathogens transmission. The insecticidal and acaricidal activity of the essential oil (EO) of Syzygium aromaticum and eugenol have already been reported, however the activity against R. sanguineus is lacked. To evaluate the acaricidal activity of S. aromaticum EO and eugenol against larvae of R. sanguineus, in vitro assays were performed using the larval immersion test. Bioassays were performed in duplicate, within the concentration range of 0.078 to 40 mg.mL-1. Mortality assessment was performed after 24 hours. Mortality above 90% was achieved through using the EO and eugenol at concentrations greater than 5 and 10 mg.mL-1, respectively. The LC50 values of 1.4 and 3.3 mg.mL-1 for eugenol and S. aromaticum EO, respectively, while the LC90 values found for eugenol and S. aromaticum EO were, respectively, 6.4 and 6.7 mg.mL-1 were calculated. These compounds present activity against R. sanguineus larvae and demonstrate potential for use as acaricides., Extratos vegetais e óleos essenciais têm apresentado potencial para uso como acaricidas. Rhipicephalus sanguineus, o carrapato marrom, parasita principalmente cães, sendo responsável pela transmissão de patógenos. O óleo essencial (OE) de Syzygium aromaticum e o eugenol já tiveram atividade inseticida e acaricida relatada, porém faltam ensaios que relatem atividade contra R. sanguineus. Com o objetivo de avaliar atividade carrapaticida de OE de S. aromaticum e eugenol frente a larvas de R. sanguineus, foram realizados ensaios in vitro por meio de Teste de Imersão Larval. Os bioensaios foram realizados em duplicata, na faixa de concentração de 0,078 a 40 mg.mL-1. A avaliação da mortalidade foi realizada após 24 horas. Mortalidade acima de 90% foi alcançada para o OE e o eugenol em concentrações superiores a 5 e 10 mg.mL-1, respectivamente. Valores de CL50 de 1,4 e 3,3 mg.mL-1 para eugenol e OE de S. aromaticum, respectivamente, enquanto os valores de CL90 encontrados para eugenol e óleo essencial de S. aromaticum foram, respectivamente, de 6,4 e 6,7 mg.mL-1. Os compostos têm atividade contra larvas de R. sanguineus e demonstram potencial para uso como acaricida.

Background The ixodid tick Amblyomma cajennense (sensu lato) complex, widespread throughout South and Central America, is also present in Mexico, Texas and Florida. As a vector of Rickettsia rickettsii, and potentially of other pathogens, infestations with A. cajennense present a substantial health risk to humans, dogs and other mammals. Oral administration of lotilaner flavored chewable tablets (CredelioTM, Elanco) to dogs was previously shown to rapidly provide killing activity of infesting ticks. This study investigated lotilaner’s efficacy against A. cajennense (s.l.). Methods Twenty purpose-bred Beagles (10 male and 10 female) were ranked by Day -5 burdens of nymphal A. cajennense (s.l.) and randomized to either treatment with lotilaner or to a sham-treated control group. On Day 0, dogs were fed within approximately 30 min prior to oral lotilaner administration at as close as possible to 20 mg/kg, the minimum dose rate. For efficacy assessments, tick counts were completed 48 h post-treatment or 48 h after experimental challenge infestations with 200 nymphal A. cajennense (s.l.) on Days -7, -2, 7, 14, 21 and 28. Results Tick infestations in the control group dogs ranged from a low of 43 to 95, with the average infestation remaining above 25% at each assessment, thereby meeting the requirement for efficacy comparison with the treated group. Lotilaner efficacy was 100% within 48 h post-treatment, and at nine days post-treatment. Efficacy was greater than 99% at all subsequent assessments through Day 30. No treatment-related adverse events were observed. Conclusion The results demonstrate that lotilaner, administered orally to dogs at a minimum dose of 20 mg/kg is well tolerated, provides rapid reduction of existing A. cajennense (s.l.) tick infestations, and provides sustained residual protection for at least 30 days against subsequent infestation by A. cajennense (s.l.).

The aim of the present study was to evaluate the efficacy of the d-phenothrin/pyriproxyfen association against Psoroptes ovis, Cheyletiella parasitivorax, and Leporacarus gibbus infestations in naturally co-infested rabbits. Twenty crossbreed (New Zealand White x California) rabbits concurrently infested by the three mite species were randomly divided in two groups. All rabbits presented with hyperemia, erythema and formation of crusts in the ear canals caused by P. ovis. Infestations by both C. parasitivorax and L. gibbus were considered asymptomatic in all animals.Ten animals were treated with a 4.4% d-phenothrin and 0.148% pyriproxyfen spray formulation until have their body surface uniformly sprayed, including external ear canals. The other ten rabbits remained untreated, serving as control group. Observations were done on days +7, +14, +21, +28, and +35 post-treatment. The d-phenothrin/pyriproxyfen association showed 100% efficacy against the three mite species and was responsible for the remission of psoroptic mange lesions on treated animals. No signs of intoxication were observed. The results indicate that d-phenothrin/pyriproxyfen spray formulation in a single application is an effective and clinically safe option for the control of different mite infestations in rabbits. O objetivo do presente estudo foi avaliar a eficácia da associação de d-fenotrina e piriproxifen no controle de infestações simultâneas por Psoroptes ovis, Cheyletiella parasitivorax e Leporacarus gibbus em coelhos naturalmente co-infestados. Vinte coelhos mestiços (Nova Zelândia Branco x Califórnia) infestados simultaneamente pelas três espécies de ácaros foram divididos aleatoriamente em dois grupos. Todos os coelhos infestados por apresentavam eritema, hiperemia e formação de crostas nas orelhas, causados por P. ovis. Infestações simultâneas por C. parasitivorax e L. gibbus foram considerados assintomáticas em todos os animais. Dez animais foram tratados com uma formulação spray contendo d-fenotrina a 4,4% e piriproxifen a 0,148%, pulverizando toda a superfície corporal de forma uniforme, incluindo a face interna das orelhas. Os outros 10 coelhos não foram t ratados, sendo mantidos como grupo controle. Os animais foram avaliados nos dias 7, 14, 21, 28 e 35 pós-tratamento. A associação de d-fenotrina e piriproxifen foi 100% eficaz no controle das três espécies de ácaros e foi responsável pela remissão das lesões de sarna psoróptica nos animais tratados. Não foram observados sinais de intoxicação. Os resultados indicam que a formulação spray de d-fenotrina e piriproxifen em uma única aplicação é uma opção clinicamente segura e eficaz no controle de infestações por ácaros em coelhos.

No presente trabalho, foram avaliadas, comparativamente, duas formulações comerciais tópicas, contendo 10% de fipronil, para o controle da pulga Ctenocephalides felis felis em gatos. O experimento foi realizado no Laboratório de Quimioterapia Experimental em Parasitologia Veterinária do Departamento de Parasitologia Animal, Instituto de Veterinária, da Universidade Federal Rural do Rio de Janeiro. Foram empregados 18 gatos, sem raça definida, divididos em três grupos de seis. Um grupo permaneceu sem tratamento (controle), e os demais foram medicados com uma formulação referência do mercado veterinário ou com uma nova formulação em teste. Os animais tratados receberam 0,5 mL do produto ao longo da região dorso-cervical e foram infestados nos dias - 2, +5, +12, +19, +26 e +33. A primeira avaliação foi realizada quatro dias após a primeira infestação e, as demais, 48 horas após cada infestação, por meio do comb test. Ambas as formulações testadas foram eficazes até o dia +35 após o tratamento, não havendo diferenças entre seus níveis de eficácia ao longo do período experimental. A nova formulação, contendo fipronil a 10%, apresentou a eficácia desejada no controle de C. f. felis em gatos. The goal of the present study was to evaluate the comparative efficacy of two topical formulations containing 10% fipronil on the control of Ctenocephalides felis felis on cats. The trial was performed at the Laboratory of Experimental Chemotherapy in Veterinary Parasitology from the Department of Animal Parasitology of the Institute of Veterinary of the Universidade Federal Rural do Rio de Janeiro. Eighteen mixed-breed cats were divided in three groups of six animals each. One group remained without treatment (control). The other groups received as treatment the two topical formulations, a commercial reference and the novel one, both containing 10% fipronil. Treated animals received 0.5 mL of product along their cervical region. Cats were infested on days - 2, +5, +12, +19, +26 and +33. Evaluations were made using the "comb test". The first one was undertaken 4 days after the initial infestation (day +2), and others 48 hours after following infestations (days +7, +14, +21, +28 and + 35). Both tested formulations had satisfactory efficacy until day + 35. No differences were observed comparing the efficacy levels between both formulations troughout the experimental period. The novel topical 10% fipronil formulation presented desirable efficacy on the control of C. f. felis on cats.

This paper reports the occurrence of parasitism by the Oriental eye-fluke, Philophthalmus gralli in ostriches reared in a commercial flock from the State of Minas Gerais State, Southeastern Brazil. The two affected birds presented lacrimation, inflammatory reaction and loss of body condition. After physical examination the birds revealed, 17 and 15 trematodes each, only in the right eyes. The economic impact of this parasite on Brazilian ostrich industry is still undetermined, requiring further studies.

Resistência antihelmíntica é um problema potencial para o controle de nematodas em bovinos e pode causar perdas econômicas na indústria de bovinos leiteiros e de cortes. O objetivo deste estudo foi determinar a eficácia da ivermectina, doramectna e abamectina em bezerros infectados naturalmente e experimentalmente para Cooperia punctata em um rebanho bovino leiteiro. Testes de redução da contagem de ovos fecais foram conduzidos em bezerros infectados naturalmente que foram tratados com soluções injetáveis de ivermectina, doramectina e abamectina. Amostras fecais foram colhidas no dia do tratamento, dia 0, e nos dias 7 e 14 após o tratamento e cultura de larvas foram feitas nas amostras positivas. Um teste controlado foi realizado usando 18 bezerros infectados artificialmente,alocados em três grupos com seis animais cada: Grupo I - controle, sem tratamento; Grupo II - ivermectina, solução injetável, 200µg/kg; Grupo III - doramectina, solução injetável, 200µg/kg. Amostras fecais foram colhidas no dia do tratamento, dia 0, e nos dias 3, 7, 9 e 14 após o tratamento. Nos dias 14, 15 e 16, dois animais de cada grupo foram eutanaziados e cargas de parasitos pulmonares e gastrintestinais foram determinados. Os resultados dos testes de redução da contagem de ovos fecais em bezerros infectados naturalmente mostraram redução no dia 14 após o tratamento de - 4,45 a 11,49% para ivermectina; 32.31 a 60.40% para doramectina e 85,05% para abamectina. O único parasito identificado na cultura de larvas foi Cooperia spp. O Teste Controlado mostrou uma redução da contagem de ovos fecais no dia 14 após o tratamento de 51.47% e 96.08% para ivermectina e doramectina, respectivamente. Redução da contagem de adultos neste teste controlado foi de 53.91% e 82.43% para ivermectina e doramectina, respectivamente. Somente C. punctata foi recuperado nas necropsias. Assim, esta cepa de C. punctata foi considerado resistente ao tratamento com ivermectina e doramectina e sugere uma possível resistência para abamectina pelo teste de redução da contagem de ovos fecais.