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The aim of this study was to evaluate the in vitro insecticidal activity of the essential oil (EO) of P. cablin against immature and adult stages of C. felis. The chemical composition of P. cablin EO was determined by gas chromatography (GC). To evaluate the insecticidal activity, the egg, larva, pupa, and adult stages of C. felis were exposed to different concentrations of P. cablin EO diluted in acetone and impregnated in filter paper in a concentration range of 25 to 200 μg.cm-2. After exposure, the material was incubated in climatized chambers and mortality assessment was performed after 24 h for the larval and adult stages, 72 h for the egg stage and 15 days for the pupal stage. After GC analysis, the major constituents of the EO of P. cablin were found to be patchoulol (27.4%), α-bulnesene (19.7%) and α-guayene (15.0%). The of mortality percentage was 100% at the concentration of 200 μg.cm-2 for all stages. The LCs50 values were 46.1, 49.2, 60.6 and 62.7 μg.cm-2, respectively for the pupal, egg, larva and adult stages. Based on the results obtained, we can conclude that the EO of P. cablin contained patchoulol, α-bulnesene, and α-guayene as major constituents and had insecticidal activity against the immature and adult stages of C. felis.

Abstract The essential oils (EOs) of Illicium verum and Pelargonium graveolens were evaluated for lethality, inhibition of development and residual efficacy against the flea Ctenocephalides felis felis. Their chemical composition was characterized by means of gas chromatography with a flame ionization and mass spectrometry detection. Mortality at different immature stages and among adult fleas was measured through in vitro filter paper tests at different concentrations of EOs. The chemical characterization of I. verum volatile oil showed that E-anethole (79.96%) was the major constituent, while the major compounds in P. graveolens were citronellol (29.67%) and geraniol (14.85%). Insecticidal activity against both immature and adult flea stages were observed. The EO of I. verum had insecticidal activity for approximately 18 days, while the EO activity of P. graveolens lasted for 13 days. The pulicidal activity of I. verum remained above 70% for up to 9 days, while the activity of P. graveolens was 41.7% for up to 2 days. Essential oils, especially that of I. verum, showed insecticidal activity for flea control at different life cycle stages and have potential for the development of ectoparasiticides (biopesticides) for veterinary use.

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.

Abstract 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.).

ABSTRACT. Avelar, B. R., Lambert, M.M, Siqueira, R.C.S., Cid, Y.P., Chaves, D.S.A., & Coumendouros K. [In vitro activity of essential oils and extracts from Schinus molle L. against Rhipicephalus microplus]. Atividade in vitro de óleos essenciais e extratos de Schinus molle L. frente a Rhipicephalus microplus. Revista Brasileira de Medicina Veterinária, 38(supl. 3):218 - 228, 2016. Programa de Pós-Graduação em Ciências Veterinárias, Instituto de Veterinária, Anexo 1, Universidade Federal Rural do Rio de Janeiro, Campus Seropédica, Ecologia, BR 465 Km 7, Seropédica, RJ 23897-970, Brasil. E-mail: katherinac@gmail.com The aim of the study was to evaluate the in vitro activity of Schinus molle L. extracts (hexane, ethyl acetate and methanol) and essential oils (leaves and fruit) on different evolutionary forms of Rhipicephalus microplus. The immersion test using engorged females was used (Drummond et al., 1973). The extract were obtained from leaves of S. molle by soxhlet and diluted in the concentration ranges between 20,000 and 1,250 ppm (parts per million), and positive and negative controls were used. The S. molle hexane extract showed efficacy in vitro of 57,7% in concentration of 1.250 ppm while other extracts and essential oils showed no significant inhibition.

ABSTRACT. Coelho C.N., Correia T.R., Oliveira G.F., Coumendouros K., Taveira M.M., Calado S.B., Avelar B.R., Nascimento C.G. & Scott F.B. [Abamectin with fluazuron association in control of ticks Rhipicephalus microplus in naturally infested cattle.] Associação de abamectina com fluazuron no controle do carrapato Rhipicephalus microplus em bovinos naturalmente infestados. Revista Brasileira de Medicina Veterinária, 37(Supl.1):51-54, 2015. Curso de PósGraduação em Ciências Veterinárias, Instituto de Veterinária, Anexo 1, Universidade Federal Rural do Rio de Janeiro, Campus Seropédica, Ecologia, BR 465 Km 7, Seropédica, RJ 23897-970, Brasil. E-mail: scott.fabio@gmail.com The purpose of the study was to evaluate the efficacy of association abamectin 0.6% and fluazuron 3.0% in control of Rhipicephalus microplus in naturally infected cattle. Were selected 20 calves that were kept in paddocks, crossbreeds Gir x Dutch, distributed in the same proportion, male and female, per experimental group, composing ten animals per group. The control group animals received no treatment, while animals in the medicated group received the formulation within the association in a single dose of 600mcg of abamectin and 3 mg of fluazuron per kg of body weight by route “pour-on”. In the days +7, +14, +21, +28, +35, +42, +49, +56, +63, +70, +77, +84, +91 were performed the counting of total number of engorged females in each animal for purposes of the evaluation of acaricide effectiveness. Statistical analysis between the average engorged females recovered between the groups control and treated showed that there was a significant difference (p = 0.05) for all subsequent time taken to treatment. The test product showed acaricide effectiveness results of 96.30% for 7 days; 96.90% for day +14; 95.98% for day +21; 96.83% for 28 days; 98.32% for 35 days; 96.12% for the day 42; 96.15% for the day +49; 98.8% for 56 days; 97.18% for 63 days, 99.12% for 70 days; 97.18% for day +77; 98.04% for the day +84 and 77.50% for the day +91. The association abamectin 0.6% with fluazuron 3.0% was effective at controlling R. microplus in cattle naturally infected for up to 63 days.

ABSTRACT. Coelho C.N., Oliveira G.F., Coumendouros K., Moraes P.A., Medeiros M.T., Borges D.A., Nascimento C.G. do, Correia T.R. & Scott F.B. [Anthelmintic efficacy of abamectin with fluazuron association in control of the gastrointestinal nematodes of cattle.] Eficácia anti-helmíntica da associação de abamectina com fluazuron no controle dos principais nematoides gastrintestinais de bovinos. Revista Brasileira de Medicina Veterinária, 37(Supl.1):100-105, 2015. Curso de Pós-Graduação em Ciências Veterinárias, Instituto de Veterinária, Anexo 1, Universidade Federal Rural do Rio de Janeiro, Campus Seropédica, Ecologia, BR 465 Km 7, Seropédica, RJ 23897-970, Brasil. E-mail: scott.fabio@gmail.com The aim of the study was to evaluate the anthelmintic efficacy of 0.6% abamectin associated with 3.0% fluazuron used respectively at doses of 600mcg and 3mg/kg of body weight by “pour-on” route in cattle, for the control of gastrintestinais nematodes Haemonchus placei, Cooperia punctata, Cooperia pectinata, Oesophagostomum radiatum and Trichostrongylus axei. To this end, two studies were conducted, a controlled one with euthanasia and necropsy, the other one evaluating the decrease of eggs per gram of feces (EPG) at the field level. For anthelmintic efficacy of the controlled study, the test product showed anthelmintic efficacy results of 92.59% for H. placei; 97.62% for T. axei; 87.82% for C. punctata; 86.96% for C. pectinata and 96% for O. radiatum. In the test conducted at a field level (EPG), the product has experienced an 92.17% efficacy results for the day +7; 89.32% for the day +14; 87.38% for day +21. The combination of abamectin and fluazuron was effective in the control of artificial infection by H. placei, O. radiatum, T. axei; and moderately effective in controlling artificial infections C. pectinata and C. punctata. The product test also showed a reduction of eggs per gram of feces (EPG) in cattle naturally infected.

ABSTRACT. Nascimento C.G., Correia T.R., Oliveira G.F., Coumendouros K., Moraes P.A., Calado S.B., Bragaglia G.N., Rosa S.C., Toma S.B. & Scott F.B. [Eprinomectin 1% Inyectable in control of Dermatobia hominis in naturally infested cattle.] Eprinomectina 1%Injetável no controle de Dermatobia hominis em bovinos naturalmente infestados. Revista Brasileira de Medicina Veterinária, 37(Supl.1):81-84, 2015. Programa de Pós-Graduação em Ciências Tecnologia e Inovação em Agropecuária, Universidade Federal Rural do Rio de Janeiro, Campus Seropédica, Ecologia, BR 465 Km 7, Seropédica, RJ 23897-970, Brasil. E-mail: scott.fabio@gmail.com The aim of the study was to evaluate the effectiveness of injectable eprinomectin 1% on the control of Dermatobia hominis in naturally infested cattle. We selected 20 calves, crossbred Gir and Holstein breed, male and female, separated into two groups, control and treated. The control group of animals received no treatment, while the animals of the treated group received eprinomectin formulation of 1% at a single dose of 1 mL/50 kg body weight (200mcg of eprinomectin/kg) per injectable route. On days +7 and +14 a count of the total number of live larvae of D. hominis on both sides of the animal for the purpose of evaluation of the effectiveness was performed. Statistical analysis of average living larvae of D. hominis counted among the groups, control and treated, showed that there was a significant difference (p ≤ 0.05) between groups on days +7 and +14. The investigational product showed an efficacy of 100% results in both experimental days. The injectable eprinomectin 1%, shown to be effective in cattle naturally infested by D. hominis (the human bot fly).

O objetivo deste estudo foi avaliar a atividade de Rosmarinus officinalis L. frente aos ectoparasitas Ctenocephalides felis felis, Rhipicephalus sanguineus e Rhipicephalus microplus. Os bioensaios seguiram a técnica impregnação em papel filtro para C. felis felis e teste de imersão de teleóginas para R. microplus e R. sanguineus. O extrato de R. officinalis L. foi obtido por maceração e sua composição química qualitativa avaliada por testes farmacopeicos. Análise fitoquímica preliminar mostrou a presença de flavonoides, taninos condensados, terpenos e saponinas. Para os testes de inibição foram preparadas diluições do extrato na faixa de concentração entre 78 e 40.000 ppm. Os resultados mostram que o extrato de R. officinalis L. apresentou atividade in vitro com resposta proporcional a concentração na faixa de 78 a 2.500 ppm para C. f. felis com valores de eficácia máximo de 95%. A eficácia carrapaticida apresentou menores valores de eficácia comparada a eficácia pulguicida em todas as concentrações testadas, com valor de eficácia máximo de 45,33 % para R. sanguineus e 28,50% para R. microplus.

O objetivo deste estudo foi avaliar a eficácia do piriprol no controle de Psoroptes ovis e Leporacarus gibbus em coelhos naturalmente infestados. Foram utilizados 12 coelhos (seis machos e seis fêmeas), adultos, com peso médio de três quilos. Seis animais foram medicados com um produto a base de piriprol na dose de 12,5mg/kg, recebendo cada um 0,1 mL no dorso e 0,1mL em cada conduto auditivo. Outros seis coelhos não foram medicados, receberam solução fisiológica na mesma proporção, sendo mantidos como grupo controle. Os animais foram avaliados nos dias 3, 7, 14, 21, 28 e 35 pós-tratamento quanto à presença de P. ovis vivos no cerúmen e quanto à presença de L. gibbus em cinco áreas distintas do corpo (pescoço, região lombar direita e esquerda, base da cauda e região inguinal). Também foi avaliado o grau de lesão nas orelhas provocada por P. ovis, antes e após o tratamento nesses mesmos dias experimentais. O produto a base de piriprol foi 100% eficaz no controle das duas espécies de ácaros e foi responsável pela remissão das lesões de sarna psoróptica nos animais tratados. Não foram observadas reações adversas em nenhum animal que recebeu o tratamento tornando-se uma ferramenta no controle desses ectoparasitas.

O objetivo deste estudo foi avaliar a atividade de Pilocarpus pennatifolius frente à Ctenocephalides felis felis, Rhipicephalus sanguineus e Rhipicephalus microplus. A realização dos ensaios in vitro procedeu-se segundo o teste de imersão de teleóginas (Drummond et al. 1973) frente à R. microplus e R. sanguineus e teste de impregnação em papel filtro frente à C. f. felis. O extrato das folhas de P. pennatifolius foi obtido por maceração exaustiva e sua composição química foi avaliada por cromatografia em camada delgada seguido de ensaios colorimétricos. Foram preparadas diluições do extrato na faixa de concentração entre 625 e 20.000 ppm. Os resultados demonstraram que o extrato de jaborandi apresentou atividade in vitro na faixa de concentração testada frente aos ectoparasitos avaliados com valores de eficácia de 35% para C. f. felis, 31,82 % para R. microplus e 59,06% para R. sanguineus.

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.

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.

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.