Resumen Rhipicephalus microplus, es la especie parasitaria que más daño genera a la ganadería mexicana y global debido a las pérdidas directas e indirectas, como lo es el incremento de la multirresistencia y la resistencia cruzada. En la actualidad, son pocos los estudios que se tienen sobre la resistencia a lactonas macrocíclicas en México, siendo su mayoría en el sur. El presente estudio tuvo como objetivo evaluar el estado de la resistencia a ivermectina en R. microplus, en el noreste de México y factores de riesgo asociados a ésta. Se colectaron 20 poblaciones de Rhipicephalus microplus, en los estados de Veracruz, Nuevo León, Tamaulipas y San Luis Potosí, y se analizaron con la prueba de inmersión de larvas. Los datos de mortalidad se sometieron a un análisis Probit, estimándose las concentraciones letales (CL) del 50% y 99% y sus respectivos intervalos de confianza del 95% (IC95%) y para la determinación de los posibles factores de riesgo se realizó un análisis multivariado y tablas de contingencia de 2 x 2 para las variables de exposición, con un intervalo de confianza del 95%, y un modelo de regresión logística binomial para aquellas variables con una P≤0.05. El 80 % de las poblaciones analizadas presentaron resistencia con rangos de RR50= 2.07-11.14 y RR99= 3.03-47.93 (P≤0.05) y mediante la regresión logística binomial, se pudo observar que la variable frecuencia de tratamientos obtuvo una P ≤0.0134, resultado que mostró ser significativo.

Abstract Rhipicephalus microplus is the parasitic species that causes the most damage to Mexican and global livestock due to direct and indirect losses, such as the increase in multidrug resistance and cross-resistance. Currently, there are few studies on resistance to macrocyclic lactones in Mexico, most of them in the south. This study aimed to evaluate the status of ivermectin resistance in R. microplus in northeastern Mexico and its associated risk factors. A total of 20 populations of Rhipicephalus microplus were collected in the states of Veracruz, Nuevo León, Tamaulipas, and San Luis Potosí, and they were analyzed with the larval immersion test. Mortality data were subjected to a Probit analysis, estimating lethal concentrations (LC) of 50 % and 99 % and their respective 95 % confidence intervals (95 % CI), and to determine possible risk factors, a multivariate analysis and 2 x 2 contingency tables were performed for the exposure variables, with a 95 % confidence interval, and a binomial logistic regression model for those variables with a P≤0.05. Eighty (80) percent of the analyzed populations showed resistance with ranges of RR50= 2.07-11.14 and RR99= 3.03-47.93 (P≤0.05), and through the binomial logistic regression, it was observed that the variable of frequency of treatments obtained a P≤0.0134, a result that proved to be significant.

ABSTRACT: Rhipicephalus (Boophilus) microplus is a hard tick endemic in livestock-growing regions and causes economic losses in the largest beef-producing countries, including Brazil, Mexico, Argentina, Australia and Uruguay. The use of chemical acaricides is still the main strategy to control R. microplusinfestations. Nevertheless, immunological control of R. microplus with an anti-tick vaccine is a suitable alternative and has manifold advantages because it can avoid drug-resistance and the presence of acaricide residues in milk, beef and in the environment. Indeed, vaccines based on the Bm86 antigen have had relative commercial and technical success to control R. microplus in some regions. Although, the efficacy of such vaccines varies among tick populations and is insufficient to provide an acceptable level of protection. Therefore, the need to search for better antigens is impelling. This review focused on the restrictions imposed on the use of acaricides in Brazil and in the European Union, as well as on the impacts of Bm86-based vaccines on R. microplus control. The efficacy of experimental anti-tick vaccines (based on subolesin, glutathione S-transferase, ferritin 2; voltage-dependent anion channel; aquaporin, 60 S acidic ribosomal protein, metalloprotease and trypsin) that can elicit an immune response against the physiological functions of various ticks is discussed.

RESUMO: O Rhipicephalus (Boophilus) microplus é um carrapato duro que é endêmico de regiões de pecuária e causa perdas econômicas nos maiores países produtores de carne bovina, incluindo Brasil, México, Argentina, Austrália e Uruguai. O uso de acaricidas ainda é a principal estratégia para controlar infestações por R. microplus. No entanto, o controle imunológico do R. microplus com uma vacina contra carrapatos é uma alternativa adequada e possui diversas vantagens, por evitar a seleção de populações de carrapato resistentes a drogas, evitar a presença de resíduos de acaricidas no leite, na carne e no ambiente. As vacinas baseadas no antígeno Bm86 tiveram relativo sucesso comercial e técnico no controle do R. microplus em diversas regiões. No entanto, a eficácia dessas vacinas varia entre as populações de carrapatos e é insuficiente para fornecer um nível aceitável de proteção. Portanto, há uma necessidade de procurar novos antígenos. Esta revisão foca nas restrições impostas ao uso de acaricidas no Brasil e na União Europeia, bem como nos impactos das vacinas baseadas em Bm86 no controle do R. microplus. Também é discutida a eficácia de vacinas anti-carrapatos experimentais (baseadas em subolesina, glutationa S-transferase, ferritina 2; canal aniônico dependente de voltagem; aquaporina, proteína ribossômica ácida 60S, metaloprotease, tripsina) que podem elicitar uma resposta imune contra as funções fisiológicas de vários carrapatos.

RESUMO Os acaricidas químicos são utilizados como o principal método para controlar Rhipicephalus (Boophilus) microplus. No entanto, o uso incorreto desses compostos ao longo dos anos levou ao surgimento de populações de carrapatos resistentes. Este estudo teve como objetivo avaliar in vitro a eficácia de diferentes combinações de acaricidas sintéticos e do óleo essencial de Plectranthus amboinicus em fêmeas ingurgitadas de R. (B.) microplus. Fêmeas ingurgitadas foram obtidas de bovinos infestados, criados em fazendas leiteiras localizadas na mesorregião do Agreste do estado de Pernambuco, Brasil. Foram utilizadas cinco combinações diferentes de acaricidas sintéticos comerciais: I) Clorpirifós 30,0g + Cipermetrina 15,0g + Fention 15,0g; II) Clorpirifós 8,5g + Cipermetrina 15,0g + Etion 16,0g; III) Deltametrina 50,0g; IV) Amitraz 12,5g; V) Clorpirifós 15,0g + Cipermetrina 25,0g + Butóxido de piperonila 50,0g, e o óleo essencial de P. amboinicus a 1% para o teste de imersão de adultos. Apenas as combinações I e V de acaricidas sintéticos, juntamente com o óleo essencial, mostraram eficácia superior a 95%. Os resultados deste estudo demonstram que populações de carrapatos resistentes estão presentes na área de estudo, e o óleo essencial de P. amboinicus é uma substância promissora para o desenvolvimento de produtos utilizados no controle de carrapatos. Por fim, é fundamental a implementação de atividades educacionais para melhorar a conscientização dos produtores quanto ao uso racional de acaricidas. Boophilus (Boophilus microplus entanto R B. B (B. infestados Pernambuco Brasil comerciais 300g g 30 0g 150g 15 II 85g 8 5g 16,0g 160g 16 III 50,0g 500g 50 IV 12,5g 125g 12 250g 25 P 1 adultos 95 95% fim (B 3 5 2 9

ABSTRACT Chemical acaricides are used as the primary method for controlling Rhipicephalus (Boophilus) microplus. However, the incorrect use of these compounds over the years has led to the emergence of resistant tick populations. This study aimed to evaluate the effectiveness of different combinations of synthetic acaricides and the essential oil of Plectranthus amboinicus on engorged females of R. (B.) microplus. Engorged females were obtained from infested bovines in dairy farms in the Agreste mesoregion of Pernambuco, Brazil. Five different combinations of commercial synthetic acaricides: I) Chlorpyrifos 30.0g + Cypermethrin 15.0g + Fenthion 15.0g; II) Chlorpyrifos 8.5g + Cypermethrin 15.0g + Ethion 16.0g; III) Deltamethrin 50.0g; IV) Amitraz 12.5g; V) Chlorpyrifos 15.0g + Cypermethrin 25.0g + Piperonyl butoxide 50.0g, and the 1% essential oil of P. amboinicus were used for the Adult Immersion Test. Only the combinations I and V of synthetic acaricides and essential oil showed efficacy over 95%. The findings of this study demonstrate that ticks’ resistant populations are present in the study area, and the essential oil of P. amboinicus is a promising compound for developing products used for tick control. Finally, it is paramount to implement educational activities to improve farmers' awareness of the rational use of acaricides. Boophilus (Boophilus microplus However R B. B (B. Pernambuco Brazil 300g g 30 0g 150g 15 II 85g 8 5g 16.0g 160g 16 III 50.0g 500g 50 IV 12.5g 125g 12 250g 25 1 P Test 95 95% ticks area control Finally farmers (B 3 5 2 9

Resumo Rhipicephalus microplus é uma das principais causas de significativas perdas econômicas na indústria pecuária, e as populações de carrapatos desenvolveram diversas formas de resistência a acaricidas. Portanto, é necessário abordar o potencial de novos compostos bioativos naturais eficazes no combate aos carrapatos. O objetivo deste estudo foi avaliar as atividades acaricida e anticolinesterase das sementes de R. aculeata e identificar compostos naturalmente ocorrentes que possam inibir a anticolinesterase por meio de docking in silico. A atividade acaricida do extrato de sementes de R. aculeata contra larvas e fêmeas adultas de R. microplus foi avaliada por meio de testes de imersão. A inibição da atividade anticolinesterase foi medida espectrofotometricamente. Extratos de sementes de R. aculeata apresentaram atividade contra larvas e fêmeas ingurgitadas de R. microplus, sendo observada também uma redução no índice reprodutivo. Rutina, ácido clorogênico, quercetina e epicatequina mostraram interações notáveis com os resíduos do sítio ativo de RmAChE. Esses resultados podem contribuir significativamente para a exploração de novos produtos naturais que potencialmente inibem RmAChE e poderiam ser utilizados no desenvolvimento de novos acaricidas para o controle de carrapatos. pecuária Portanto R silico imersão espectrofotometricamente reprodutivo Rutina clorogênico

Abstract Rhipicephalus (Boophilus) microplus is a leading cause of significant economic losses in the livestock industry, and tick populations have developed multiple forms of resistance to acaricides; therefore, the potential of novel natural bioactive compounds that are effective for targeting ticks must be addressed. The aim of this study was to evaluate the acaricidal and anticholinesterase activities of R. aculeata seeds and to identify naturally occurring compounds that potentially inhibit anticholinesterase through in silico docking. The acaricidal activity of the extract of R. aculeata seeds against larval and adult R. microplus ticks was assessed through immersion tests. Inhibition of anticholinesterase activity was measured spectrophotometrically. Extracts of R. aculeata seeds showed activity against larvae and engorged females of R. microplus, and a reduction in the reproductive index were also observed. Rutin, chlorogenic acid, quercetin, and epicatechin exhibited noteworthy interactions with the active site residues of RmAChE. These findings could significantly contribute to the exploration of novel natural products that can potentially inhibit RmAChE and could be used in the development of new acaricides for tick control. Boophilus (Boophilus industry therefore addressed R docking tests spectrophotometrically observed Rutin acid quercetin control

RESUMEN Eryngium foetidum L. es una hierba bienal perteneciente a la familia Apiaceae, que se utiliza ampliamente como planta medicinal en la mayoría de las regiones tropicales. En este trabajo de investigación, se estudió la actividad del aceite esencial (AE) de E. foetidum contra Hyalomma lusitanicum, Koch, y su fitotoxicidad en la germinación de semillas de Lolium perenne y Lactuca sativa. El AE de E. foetidum se obtuvo mediante la técnica de hidrodestilación. Se utilizó cromatografía de gases acoplada a espectrometría de masas (GC-MS) para identificar los metabolitos volátiles. Se encontraron quince compuestos en el AE de E. foetidum. Los principales compuestos fueron E-2-dodecenal (53,0%), trimetilbenzaldehído (duraldehído) (14,8%), ciclododecano (4,4%), trans-tetradec-enal (3,9%), decanal (3,6%), trans-2-dodecen-1-ol (3,0%) y D-limoneno (1,5%), respectivamente. El AE de E. foetidum, y dos de sus compuestos principales individuales (2-dodecenal, y duraldehído) tuvieron baja actividad fitotóxica cuando fueron comparados con el porcentaje de inhibición de la germinación del control (carvona), en semillas de L. perenne y L. sativa. En cuanto a la actividad acaricida contra Hyalomma lusitanicum, la CL50 (µg µL-1) se determinó mediante un análisis probit (P>0,05). El aceite esencial de E. foetidum mostró una mortalidad del 100% sobre H. lusitanicum a una concentración de 10 µg µL-1, y CL50 = 4.2 µg µL-1. Los resultados obtenidos del aceite esencial de E. foetidum muestran un gran potencial para desarrollar biocidas naturales para el control de H. lusitanicum debido a su composición química rica en aldehídos y derivados bencénicos, y sin efectos fitotóxicos adversos.

ABSTRACT Eryngium foetidum L. is a biennial herb belonging to the family Apiaceae, which is used extensively as a medicinal plant in most tropical regions. In this research work, the activity of the essential oil (EO) from E. foetidum against the Hyalomma lusitanicum Koch, and its phytotoxicity in germination of seeds of Lolium perenne and Lactuca sativa was studied. E. foetidum EO was isolated by the hydrodistillation technique. Gas chromatography coupled to mass spectrometry (GC-MS) was used to identify the volatile metabolites. Fifteen compounds were found in the E. foetidum EO. The major compounds were E-2-dodecenal (53.0%), trimetilbenzaldehyde (duraldehyde) (14.8%), cyclododecane (4.4%), trans-tetradec-enal (3.9%), decanal (3.6%), and trans-2-dodecen-1-ol (3.0%) and D-limonene (1.5%), respectively. The E. foetidum EO, and two of its individual main compounds (2-dodecenal, and duraldehyde) had low phytotoxic activity when were compared with the percentage of inhibition of germination of the control (carvone), in seeds of L. perenne and L. sativa. The acaricidal activity against Hyalomma lusitanicum was determined using a probit analysis (P>0.05). The essential oil of E. foetidum showed 100% mortality on H. lusitanicum at a concentration of 10 µg µL-1, and LC50 = 4.2 µg µL-1. The results obtained from the essential oil of E. foetidum show a great potential to develop natural biocides for the control of H. lusitanicum due to its chemical composition rich in aldehydes and benzene derivatives, and without adverse phytotoxic effects.

Resumen Tetranychus urticae Koch es la plaga más importante en el cultivo del rosal, ya que reduce la calidad de la producción e incrementa los costos de manejo, en consecuencia, los acaricidas se han utilizado ampliamente para su control. Por lo anterior se realizaron pruebas de susceptibilidad para la determinación de resistencia en hembras adultas de T. urticae a los acaricidas, abamectina, acequinocyl, clorfenapir y extracto de Cinnamomum zeylanicum J. Presl, sobre tres poblaciones de Tenancingo, Estado de México y una línea susceptible. La investigación se realizó en 2021 en el Departamento de Parasitología Agrícola, para la evaluación de los plaguicidas se empleó la técnica de inmersión en hoja (IRAC, 2009). Los resultados demostraron que la población que presentó tendencia a desarrollar resistencia al plaguicida abamectina fue la L3 (Rancho Lizflor), mientras que las poblaciones L1 (Rancho Los Pilares) y L2 (Rancho Isoflor) se condujeron hacia el acaricida acequinocyl, por lo que se recomienda la disminución de las aplicaciones y rotación de plaguicidas de distinto grupo toxicológico. Para el resto de los plaguicidas no se reportó resistencia en ninguna de las poblaciones en estudio, por tal motivo se les puede considerar efectivos para el control de T. urticae en Tenancingo, Estado de México.

Abstract Tetranychus urticae Koch is the most important pest in rose crops, since it reduces the quality of production and increases management costs, consequently, acaricides have been widely used for its control. Therefore, susceptibility tests were performed to determine resistance in adult females of T. urticae to acaricides, abamectin, acequinocyl, chlorfenapyr, and extract of Cinnamomum zeylanicum J. Presl, on three populations of Tenancingo, State of Mexico and a susceptible line. The research was carried out in 2021 in the Department of Agricultural Parasitology, the leaf immersion technique was used for the evaluation of the pesticides (IRAC, 2009). The results demonstrated that the population that showed a tendency to develop resistance to the pesticide abamectin was L3 (Rancho Lizflor), while the populations L1 (Rancho Los Pilares) and L2 (Rancho Isoflor) had a tendency towards the acaricide acequinocyl, so it is recommended to reduce the applications and rotation of pesticides of different toxicological group. For the rest of the pesticides, no resistance was reported in any of the populations under study, for this reason they can be considered effective for the control of T. urticae in Tenancingo, State of Mexico.

Resumen Las infestaciones de garrapatas representan una gran dificultad para la producción de ganado bovino en países tropicales y subtropicales alrededor del mundo. Las formas tradicionales de combate a esta plaga son químicos (acaricidas) y manejo integral de pastizales. Sin embargo, estos métodos no han logrado controlar de manera contundente la presencia de este ectoparásito. Lo anterior ha llevado a la búsqueda de vacunas que permitan el control de estos parásitos. Actualmente, se cuenta con inmunógenos que contienen el antígeno intestinal Bm86 de Rhipicephalus microplus, los cuales han demostrado ser una alternativa efectiva, al reducir las poblaciones de garrapatas y el uso de acaricidas sintéticos. No obstante, el polimorfismo de este locus en garrapatas de distintas zonas geográficas representa una limitante en su efectividad. Se han realizado un número importante de investigaciones acerca del gen Bm86 como antígeno vacunal, por lo que, en este documento, se presenta una actualización de las investigaciones realizadas con este antígeno y su potencial uso como control inmunológico para reducir las infestaciones de garrapatas en el ganado bovino.

Abstract Tick infestations represent a major difficulty for cattle production in tropical and subtropical countries around the world. The traditional ways to combat this pest are chemicals (acaricides) and integrated management of grasslands. Nevertheless, these methods have not been able to conclusively control the presence of this ectoparasite. This has led to the search for vaccines that allow the control of these parasites. Currently, there are immunogens containing the gut antigen Bm86 of Rhipicephalus microplus, which have proven to be an effective alternative, as they have reduced tick populations and the use of synthetic acaricides. However, the polymorphism of this locus in ticks from different geographical areas represents a limitation in its effectiveness. A significant number of studies have been conducted on the Bm86 gene as a vaccine antigen, so this paper presents an update on studies conducted with this antigen and its potential use as an immunological control to reduce tick infestations in cattle.

Resumo O uso de acaricidas se tornou prática comum para o controle de pragas em todo o mundo, incluindo a Arábia Saudita. Apesar de matar as pragas-alvo, esses inseticidas também afetam o crescimento de ácaros predadores. O presente estudo foi conduzido para avaliar o impacto de dois acaricidas, abamectina e hexythiazox, em sete espécies de ácaros predadores. Soluções padrão de abamectina (8.4% w/v) e hexitiazox (10% w/w) foram adquiridas e preparadas para pulverização direta. Os acaricidas foram testados em três concentrações seriais de dose recomendada (RD), metade da dose recomendada (HRD) e o dobro da dose recomendada (DRD). Os ensaios foram feitos em ovos, ninfas e adultos das sete espécies de ácaros predadores em condições de laboratório. O efeito dos acaricidas aplicados foi determinado uma semana após a aplicação. Os resultados do estudo revelaram que todas as doses de hexitiazox e abamectina são tóxicas para as ninfas e adultos de todas as sete espécies de ácaros predadores, mas em extensão variável. Além disso, foi observado que hexitiazox e abamectina reduziram a porcentagem de eclosão de ovos para todas as sete espécies de ácaros predadores. Verificou-se que o hexitiazox é mais tóxico do que a abamectina para todos os sete ácaros predadores. A mortalidade mais alta foi registrada no DRD e RD, enquanto a mortalidade mínima foi registrada no HRD. O efeito acaricida é menos severo em ovos para incubação do que em imaturos e adultos de ácaros predadores. As espécies variam em suscetibilidade a acaricidas, e em algumas populações foi observada resistência. Com base neste estudo, recomenda-se que o uso frequente de acaricidas contra ácaros fitófagos seja evitado e a viabilidade de programas de controle biológico seja promovida para proteger o meio ambiente, a saúde de indivíduos vivos e de organismos não visados.

Abstract Use of acaricides has become a common practice to control pests all over the world including Saudi Arabia. In spite of killing the targeted pests, such insecticides also effect growth of predatory mites. Present study has been conducted to evaluate the impact of two acaricides, abamectin and hexythiazox, on seven species of predatory mites. Standard solutions of abamectin (8.4% w/v) and hexythiazox (10% w/w) were purchased and prepared for direct spray. Acaricides were tested at three serial concentrations of recommended dose (RD), half of the recommended dose (HRD) and double the recommended dose (DRD). Trials were made on eggs, nymphs and adults of the seven species of predatory mites under laboratory conditions. Effect of the applied acaricides was determined one week after the application. The results of the study revealed that all doses of hexythiazox and abamectin are toxic to the nymphs and adults of all seven species of predatory mites but to the variable extent. Furthermore, it was observed that hexythiazox and abamectin reduced the percentage of egg hatching for all seven species of predatory mites. Hexythiazox was found to be more toxic than abamectin to all seven predatory mites. Higher mortality was recorded at DRD and RD, while minimum mortality was recorded at HRD. Acaricidal effect is less severe on hatching eggs than on immatures and adults of the predatory mites. Species vary in susceptibility to acaricides and in some populations resistance has been observed. Based upon this study, it is recommended that the frequent use of acaricides against phytophagous mites should be avoided and feasibility of biological control programs should be promoted to protect the environment, health of living individuals and the non-target organisms.

Abstract In dogs, Rhipicephalus linnaei transmits pathogens such as Ehrlichia canis, Babesia vogeli, and Hepatozoon canis. The veterinary market has synthetic acaricides to ticks control. Esters derived from castor oil are efficient. However, there is little information about their effects on non-target organisms. This work consisted of a clinical (AST, ALT, and ALP) and histological and histochemical analysis (liver and spleen) of female rabbits exposed to these esters and afoxolaner. The rabbits were divided into three groups: control group (CG) received Bandeirante® rabbit feed; the afoxolaner treatment (TG1) received rabbit feed and two doses of afoxolaner; castor oil esters treatment (TG2) received rabbit feed enriched with esters (1.75 g esters/kg). No alterations were observed in the AST, ALT, and ALP enzymes in exposure to esters TG2. Rabbits from TG1 showed changes in AST. The liver of rabbits exposed to afoxolaner underwent histological and histochemical changes, such as steatosis and vacuolation, as well as poor protein labeling. Polysaccharides were intensely observed in the group exposed to esters. The spleen showed no changes in any of the exposure. Esters from castor oil caused fewer liver changes when incorporated into the feed and fed to rabbits than exposure to afoxolaner.

Resumo Carrapatos Rhipicephalus linnaei transmitem patógenos como Ehrlichia canis, Babesia vogeli e Hepatozoon canis, para os cães. O mercado veterinário dispõe de acaricidas sintéticos para o controle desses ectoparasitas. Ésteres derivados do óleo de mamona são eficientes, mas há pouca informação sobre seus efeitos em organismos não-alvos. Esse trabalho objetivou analisar clínica (AST, ALT e ALP), histológica e histoquímicamente (fígado e baço) coelhas expostas aos ésteres e ao afoxolaner, tendo sido as mesmas alocadas nos grupos: Controle (GC) que recebeu ração Bandeirante®; Tratamento 1 (TG1), além da ração foram expostas ao afoxolaner, Tratamento 2 (TG2) receberam ração enriquecida com os ésteres (1,75 g ésteres/kg). Não houve alterações nas enzimas AST, ALT e ALP na exposição aos ésteres (TG2). No TG1 houve alterações na AST. O fígado das coelhas do TG1 apresentou alterações histológicas e histoquímicas, tais como esteatose e vacuolização, bem como fraca marcação de proteínas. Polissacarídeos foi intensamente marcados no fígado do TG2. O baço não apresentou alterações em nenhum dos grupos. Os ésteres do óleo de mamona causaram menos alterações hepáticas nas coelhas do que quando elas foram expostas ao afoxolaner.

Resumen Las garrapatas han afectado negativamente la producción bovina, provocando grandes pérdidas económicas; debido al uso indiscriminado de productos químicos han desarrollado resistencia, obligando a la búsqueda de alternativas de control, presentándose interés en investigar las propiedades acaricidas de especies vegetales, el objetivo del estudió fue determinar la eficacia del extracto natural Phytolacca bogotensis y Alnus alcuminata en el control in vitro de la garrapata adulta Rhipicephalus (Boophilus) microplus. El método empleado para la elaboración de los extractos de las plantas analizadas fue la extracción en caliente "Soxhlet", y se evaluaron los metabolitos secundarios mediante pruebas cualitativas. Se expusieron garrapatas adultas mediante la técnica de inmersión a los extractos puros y diluciones. A las 24, 48, 72 y 96h post-exposición, se evaluó la mortalidad tomándose como mínimo eficaz una mortalidad de 60%. El extracto de P. bogotensis, mostró una efectividad con el extracto puro y la dilución 1:2 y el extracto puro de A. alcuminata no supero el mínimo eficaz de mortalidad. Se observó que el extracto P bogotensis, mostró mayor eficacia en el control de la garrapata adulta Rhipicephalus (Boophilus) microplus, constituyéndose como una fuente de principios activos que contribuyan al descubrimiento de ixodicidas de origen natural.

Abstract Ticks have negatively affected cattle production, causing great economic losses; due to the indiscriminate use of chemical products they have developed resistance, forcing the search for control alternatives, presenting an interest in investigating the acaricidal properties of plant species, the objective of the study was to determine the efficacy of the natural extract Phytolacca bogotensis and Alnus alcuminata in the control in vitro of the adult tick Rhipicephalus (Boophilus) microplus. The method used for the elaboration of the extracts of the analyzed plants was the hot extraction "Soxhlet", and the secondary metabolites were evaluated through qualitative tests. Adult ticks were exposed by the immersion technique to the pure extracts and dilutions. At 24, 48, 72 and 96h post-exposure, mortality was evaluated, taking a mortality of 60% as the minimum effective. The P. bogotensis extract showed effectiveness with the pure extract and the 1:2 dilution, and the pure extract of A. alcuminata did not exceed the minimum effective mortality rate. It was observed that the P bogotensis extract showed greater efficacy in the control of the adult tick Rhipicephalus (Boophilus) microplus, constituting itself as a source of active principles that contribute to the discovery of ixodicides of natural origin.

RESUMO Rhipicephalus (Boophilus) microplus (Canestrini) é um dos parasitas que mais impactam a pecuária de países tropicais e subtropicais, incluindo o Brasil, com perdas em torno de US$ 3,24 bilhões por ano. Ocorrências de populações resistentes a diferentes classes de acaricidas e suas associações têm sido amplamente diagnosticadas em todo o Brasil. Para isso, bioensaios utilizando o teste de pacote larval (LPT) impregnado com cipermetrina e diazinon em diferentes concentrações foram realizados para caracterizar a resistência fenotípica (nível de resistência, RL), a resistência molecular (mutação no domínio III - S6 T2134A) e o metabolismo enzimático do diazinon e da cipermetrina em algumas populações de R. (Boophilus) microplus coletadas em diferentes regiões do estado de São Paulo. Dentre as 40 propriedades analisadas, 18 delas apresentaram fatores de resistência à cipermetrina, sendo RL I (53%) e RL II (47%). A mutação do domínio III T2134A foi encontrada pela primeira vez no Brasil, em sete fazendas. Larvas heterozigotas foram constatadas em seis delas, e larvas homozigotas resistentes em quatro. Nenhuma diferença (P>0,05) na atividade enzimática de α-esterase e β-esterase foi observada em testes com larvas vivas e mortas em uma concentração de cipermetrina de 409,6μg/cm2. Noventa por cento das propriedades apresentaram resistência ao agente ativo diazinon: RL I em 6%, RL II em 30% e RL III em 64%. Houve diferenças significativas (P<0,05) na atividade enzimática na concentração mais elevada (3,2μg/cm2) entre os grupos de larvas vivas e mortas.

ABSTRACT Rhipicephalus (Boophilus) microplus is one of the parasites that has an impact on livestock farming in Brazil. Bioassays using the larval packet test (LPT) impregnated with cypermethrin and diazinon at different concentrations were performed to characterize phenotypic resistance (resistance level, RL), molecular resistance (mutation in domain III - S6 T2134A) and enzymatic metabolism of diazinon and cypermethrin in some populations of R. microplus that were collected in different regions of the state of São Paulo. Among the 40 farms analyzed, 18 of them presented resistance factors for cypermethrin, with RL I (53%) and RL II (47%). Mutation of domain III T2134A was found for the first time in Brazil, on seven farms. Heterozygous larvae were found on six of them and resistant homozygous larvae on four. No differences (p>0.05) in enzymatic activity of α-esterase and β-esterase were found in tests with live and dead larvae at a cypermethrin concentration of 409.6μg/cm2. Ninety percent of the farms showed resistance to the active agent diazinon: RL I in 6%, RL II in 30% and RL III in 64%. There were significant differences (p<0.05) in enzymatic activity at the highest concentration (3.2μg/cm2).

Resumen Objetivos. Determinar la efectividad de acaricidas en poblaciones de campo de Rhipicephalus (Boophilus) microplus colectadas en fincas ganaderas de los municipios de Ibagué, Espinal y Cajamarca, departamento del Tolima. Metodología. En 12 fincas se colectaron 1200 teleoginas de R. microplus que fueron sometidas a una prueba de inmersión de adultas (PIA) modificada, a fin de evaluar cuatro acaricidas comúnmente usados en la región: cipermetrina al 15%, amitraz al 20,8%, etión al 84% e ivermectina al 1%. Se calcularon parámetros como la eficiencia reproductiva y el porcentaje de eclosión, con los cuales se determinó la eficacia de cada acaricida. Resultados. Se encontró que en el 91,66% de los predios evaluados las poblaciones de R. microplus fueron resistentes a la cipermetrina, el 91,66% al amitraz, 75% a etión y 66,66% a ivermectina, evidenciando pérdida de eficacia de estos químicos. Conclusión. Se demostró la alta dispersión de resistencia a los acaricidas de uso frecuente en campo para el control de poblaciones de R. microplus en tres municipios del Tolima, denotando la necesidad de establecer nuevas estrategias de control que permitan limitar las infestaciones de la garrapata común del ganado.

Abstract Objectives: To determine the effectiveness of acaricides in field populations of Rhipicephalus (Boophilus) microplus collected in cattle farms in the municipalities of Ibagué, Espinal and Cajamarca, department of Tolima. Methodology: A total of 1200 teleogines of R. microplus were collected in 12 farms and subjected to a modified adult immersion test (AIT) in order to evaluate four commonly used acaricides in the region: cypermethrin 15%, amitraz 20.8 %, 84% ethion and 1% ivermectin. Parameters such as reproductive efficiency and hatching percentage were calculated, with which the efficacy of each acaricide was determined. Results: It was found that in 91.66% of the farms evaluated the populations of R. microplus were resistant to cypermethrin, 91.66% to amitraz, 75% to ethion and 66.66% to ivermectin, showing loss of efficacy of these chemicals. Conclusion: The high dispersion of resistance to the acaricides frequently used in the field for the control of populations of R. microplus in three municipalities of Tolima was demonstrated, denoting the need to establish new control strategies that allow limiting infestations of the common cattle tick.

RESUMEN Introducción: En Costa Rica se procesan anualmente 681 millones de litros de leche, debido al alto consumo per cápita que es de 216 kilogramos, por lo que es particularmente importante evitar los efectos tóxicos de la leche contaminada, asociados a vómitos, parálisis y calambres, y, a largo plazo, cáncer, trastornos endocrinos, diabetes y alteraciones cromosómicas, entre otros. Objetivo: Determinar los niveles de residuos de cinco acaricidas usados en Costa Rica: Amitraz, Coumafós, Clorpirifós, Ciflutrina y Cipermetrina, en muestras de leche entera bovina de Costa Rica. Métodos: De enero a setiembre del 2018 tomamos muestras en 200 sistemas de producción de seis provincias y aplicamos técnicas de cromatografía de gases y de líquidos, acopladas a espectrometría de masas. Resultados: no hallamos residuos de Coumafós y la Ciflutrina, pero en 19 fincas detectamos Amitraz, Cipermetrina y Clorpirifós (este último, 0,01mg/kg). Pocos encargados conocen alternativas al control químico, y la mayoría ni respeta el periodo de retiro del garrapaticida, ni hace la rotación del ingrediente activo. Conclusión: Se debe mejorar la educación y el monitoreo sobre el uso de garrapaticidas en los sistemas de producción de leche.

ABSTRACT ''Acaricide residues in whole bovine milk from Costa Rica''. Introduction: Because of the high per capita consumption of 216 kilograms, in Costa Rica, 681 million liters of milk are processed annually, and it is particularly important to avoid the toxic effects of contaminated milk, associated with vomiting, paralysis and cramps, and, in the long term, cancer, endocrine disorders, diabetes and chromosomal alterations, among others. Objective: To determine the residue levels of five acaricides used in Costa Rica: Amitraz, Coumafos, Chlorpyrifos, Cyfluthrin and Cypermethrin, in samples of whole bovine milk. Methods: From January to September 2018, we collected samples from 200 production systems in six provinces and applied gas and liquid chromatography techniques coupled with mass spectrometry. Results: We did not find residues of Coumafos and Cyfluthrin, but in 19 farms we detected Amitraz, Cypermethrin and Chlorpyrifos (the latter, 0.01mg/kg). Few managers know alternatives to chemical control, and most do not respect the withdrawal period of the tick, and do not rotate the active ingredient. Conclusion: Education and monitoring on tick control should be improved in dairy farms.

Resumen El objetivo fue evaluar un esquema de control integrado para Rhipicephalus (Boophilus) microplus en vacas preñadas y con cría combinando dos tratamientos con acaricidas químicos y el descanso de potreros en una localidad representativa del noreste argentino. Este esquema fue diseñado para combinar el efecto terapéutico del control estratégico (dos tratamientos aplicados entre fines del invierno y la primavera) con el que tiene el descanso de las pasturas (en el presente trabajo de tres meses) sobre la cantidad de larvas presentes en un potrero. Veintidós vacas y vaquillas de biotipo Braford fueron distribuidas en dos grupos en potreros infestados naturalmente con garrapatas, con un descanso de tres meses previo al ingreso de los animales. El grupo I recibió dos tratamientos acaricidas con fluazurón y flumetrina y el grupo II permaneció sin tratamientos como grupo control. Se estimó mensualmente la infestación con garrapatas y se calculó la eficacia terapéutica. La infestación con Rhipicephalus (Boophilus) microplus en el grupo I fue significativamente menor que la del grupo control y los niveles de eficacia fueron siempre superiores al 93%, con la excepción del conteo de febrero dónde el porcentaje de eficacia fue del 89,1%. La integración complementaria de la descontaminación parcial ejercida mediante un descanso de pasturas de tres meses con un esquema de tratamientos estratégicos (dos en un período de 10 meses) permitió alcanzar niveles significativos de eficacia en el control de Rhipicephalus (Boophilus) microplus manteniendo bajos niveles de infestación con mínimos movimientos a corral, y brindando sustentabilidad al uso de los acaricidas.

Abstract The aim was to evaluate an integrated control scheme for Rhipicephalus (Boophilus) microplus in pregnant and calving cows combining two treatments with chemical acaricides and paddock rest in a representative locality of northeastern Argentina. This scheme was designed to combine the therapeutic effect of strategic control (two treatments applied between late winter and spring) with the rest of pastures (in the present work of three months) on the amount of larvae present in a paddock. Twenty-two Braford-type heifers and cows were divided into two groups in paddocks naturally infested with ticks, with a rest of three months before the animals were admitted. Group I received two acaricidal treatments with fluazuron and flumethrin and group II remained without treatment as a control group. Tick infestation was monitored monthly and therapeutic efficacy was calculated. The infestation with Rhipicephalus (Boophilus) microplus in group I was significantly lower than that of the control group and the efficacy levels were always higher than 93%, with the exception of the February count, where the efficacy was 89.1%. The complementary integration of the partial decontamination applied through a three-month pasture rest with a strategic treatment scheme (two in a 10-month period) allowed reaching significant levels of efficacy in the control of Rhipicephalus (Boophilus) microplus while maintaining low levels of infestation with minimal movements to management pens, and providing sustainability to the use of acaricides.

Resumo O controle do carrapato representa um grande desafio na saúde animal. O objetivo deste trabalho foi avaliar a eficácia de compostos acaricidas contra Rhipicephalus microplus em sistemas de pecuária leiteira no Paraná, Brasil. Foram selecionadas seis fazendas (PR1-PR6), onde são aplicados produtos carrapaticidas regularmente. Duas outras fazendas que adotaram protocolos alternativos, PRS (tratamento seletivo) e PRA (controle agroecológico individual), também foram incluídas nos testes. R. microplus ingurgitadas foram coletados para testes in vitro de imersão em adultos (TIA) e teste de eclosão de ovos (TEO) em todas as oito populações. O teste de envelope de larvas (TEL) foi utilizado nas populações PR6 e PRA. Os grupos de tratamento foram compostos por G1: diclorvos 45% mais cipermetrina 5%, G2: deltametrina 2,5%, G3: cipermetrina 15%, clorpirifos 25% e mais citronelal 1% e G4: amitraz 12,5%. A eficácia em PR1 a PR6 revelou que G3 e G4 obtiveram eficácia de moderada a alta, variando de 75,0% a 100,0% e 73% a 98%, respectivamente. No TEL, a eficácia em PR6 foi de 76,0%, 67,0%, 93,0% e 30,6%, enquanto em PRA apresentou 100,0%, 100,0%, 100,0% e 54,0%, para G1, G2, G3 e G4, respectivamente. Estratégias sustentáveis de controle são discutidas neste documento.

Abstract Tick control represent a great challenge to animal health. The objective of this study was to evaluate the efficacy of acaricidal compounds against Rhipicephalus microplus from dairy cattle systems in Paraná State, Brazil. Six farms (PR1-PR6) were selected, where anti-tick products were applied at fixed intervals. Two other farms that adopted alternative protocols; target selective treatment (PRS), and individual-based agroecological protocol (PRA) were also included in the trial. Fully engorged R. microplus were collected for the in vitro adult immersion test (AIT), and the egg hatch test (EHT) in all eight populations. The larval packet test (LPT) was used on PR6 and PRA tick populations. The treatment groups were composed of G1: dichlorvos 45% plus cypermethrin 5%, G2: deltamethrin 2.5%, G3: cypermethrin 15%, chlorpyriphos 25%, plus citronellal 1%, and G4: amitraz 12.5%. The efficacy at PR1 to PR6 revealed that G3 and G4 achieved moderate to high efficacy, from 75.0 to 100.0% and 73 to 98%, respectively. In the LPT, the efficacy at PR6 was 76.0, 67.0, 93.0 and 30.6%, while PRA presented 100.0, 100.0, 100.0, and 54.0%, for G1, G2, G3 and G4, respectively. Sustainable parasite control strategies are discussed.