Parásitos en un venado de cola blanca silvestre en Cajamarca, Perú

En el presente estudio se informa sobre los parásitos encontrados en un venado de cola blanca, Odocoileus virginianus peruvianus, capturado en el bosque seco del distrito de Paccha, provincia de Chota, departamento de Cajamarca. El Servicio Nacional Forestal y de Fauna Silvestre recuperó los parásitos de un espécimen macho adulto y las remitió al Centro de Investigación en Medicina Tropical de la Universidad Nacional de Cajamarca para la identificación taxonómica de helmintos y artrópodos, y análisis coproparasitológico. Se identificaron dos metacéstodos correspondientes a Cysticercus tenuicollis. En los análisis coproparasitológicos cualitativos se hallaron huevos de Nematodirus spp. en una carga de 10 por gramo de heces (h.p.g.) y 40 h.p.g. tipo Strongílidos que no pudieron diferenciarse por la baja carga en el coprocultivo. No se detectaron huevos de trematodos en la sedimentación. De ectoparásitos, se identificaron ocho garrapatas duras Rhipicephalus (Boophilus) microplus y cinco piojos chupadores Solenopotes binipilosus. Varios de los ejemplares fueron depositados en el Museo de Historia Natural de la Universidad Nacional Mayor de San Marcos, Lima. Los hallazgos representan el primer reporte formal de la garrapata común del ganado en esta subespecie de cérvido. Además, se registra por primera vez la presencia del piojo Solenopotes binipilosus en territorio peruano.

In the present study, findings regarding parasites discovered in a white-tailed deer, Odocoileus virginianus peruvianus, captured in the dry forest of the Paccha district, Chota province, Cajamarca department, are reported. The Servicio Nacional Forestal y de Fauna Silvestre recovered parasites from an adult male specimen and forwarded them to the Tropical Medicine Research Center at the Universidad Nacional de Cajamarca for taxonomic identification of helminths and arthropods, as well as coproparasitological analysis. Two metacestodes corresponding to Cysticercus tenuicollis were identified. Qualitative coproparasitological analyses revealed Nematodirus spp. eggs at a concentration of 10 eggs per gram of feces (EPG) and 40 EPG of Strongylid type that could not be differentiated due to low counts in the coproculture. No trematode eggs were detected in the sedimentation. Among ectoparasites, eight hard ticks Rhipicephalus (Boophilus) microplus and five sucking lice Solenopotes binipilosus were identified. Several specimens were deposited in the Museo de Historia Natural de la Universidad Nacional Mayor de San Marcos, Lima. These findings represent the first formal report of the common cattle tick in this subspecies of cervid. Additionally, the presence of the Solenopotes binipilosus louse in Peruvian territory is reported for the first time.

Sequence characteristics of Rhipicephalus microplus Enolase gene and prediction of structure and antigenic epitopes of its encoding protein / 中国血吸虫病防治杂志

Objective To analyze the sequence characteristics of Rhipicephalus microplus Enolase gene, and to predict the secondary and tertiary structure and antigenic epitopes of the Enolase protein. Methods Sixty-two engorged female R. microplus were sampled from a yellow cattle breeding farm in Zhijiang County, Huaihua City, Hunan Province in June 25, 2022. Genomic DNA was isolated from R. microplus, and the Enolase gene was amplified using PCR assay, followed by cloning, sequencing and expression of the amplification product. The sequence characteristics of the Enolase gene were analyzed using the software Clustal X, and the gene sequence was translated into amino acid sequences. The secondary and tertiary structures of the Enolase protein were deduced using the software PRABI, and the physicochemical properties of the Enolase protein were analyzed using the software PRABI. In addition, the B- and T-cell epitopes of the Enolase protein were predicted using the software ABCpred Prediction, Scratch, IEDB and NetCTL. Results The R. microplus Enolase gene sequence was 1 323 bp in size, and the contents of A, T, G and C bases were 24.5%, 22.5%, 27.0% and 26.0%,with 47.0% of A + T content and 53.0% of G + C content. The R. microplus Enolase gene encoded 434 amino acids, and the Enolase protein had a molecular weight of 47.12 kDa. The secondary structure of the Enolase protein contained 186 α-helixes (42.86%), 32 β-turns (7.37%), 144 random coils (33.18%) and 72 extended strands (16.59%). The Enolase protein was most probably present in cytoplasm (76.7%), followed by in mitochondrion (39.1%) and nucleus (21.7%), and the Enolase protein had no signal peptide or transmembrane domain. In addition, the Enolase protein had 14 B-cell dominant epitopes and 8 T-cell dominant epitopes. Conclusions The R. microplus Enolase gene sequence exhibits a GC preference, and its encoding Enolase protein is an acidic and hydrophilic protein, with α-helixes and random coils as its primary structure, and presenting B- and T-cell dominant epitopes, which is a potential target for development of vaccines against R. microplus.

Molecular prevalence of Anaplasma marginale in ruminants and Rhipicephalus ticks in northern Pakistan

@#Anaplasma marginale is the most prevalent tick-borne haemoparasite of cattle and causes huge economic losses to the dairy industry worldwide. This study aimed to determine the occurrence of A. marginale infection in blood and tick samples collected from livestock animals in the districts located in Khyber Pakhtunkhwa (KPK), Pakistan. A total of 184 blood and 370 tick samples were included in this study. It has never been reported that sheep, goats, and cattle in Tank, Ghulam Khan, Birmil and Miran Shah areas were infected with A. marginale. All samples of blood and ticks were collected through random sampling from March 2021 to January 2022 from cattle, sheep and goats and screened through PCR for anaplasmosis by using primer pairs of Anaplasma spp. Three hundred and seventy ticks were collected from infested hosts (120/184, 64.21%). Among the four morphologically identified tick species, the highest occurrence was recorded for Rhipicephalus sanguineus (n=138, 37.29%), followed by Rhipicephalus microplus (n=131, 35.4%), Rhipicephalus annulatus (n=40, 10.81%), Hyalomma anatolicum (n=31, 8.37%), and Hyalomma marginatum (n=30, 8.1%). The occurrence of female tick was highest (n=160, 43.24%), followed by nymphs (n=140, 37.38%) and males ticks (n=70, 18.9%). Among these ticks, A. marginale was detected in female ticks of R. microplus, and R. sanguineus. Molecular identification of A. marginale was confirmed in 120 out of 184 blood samples and 6 out of 74 tick samples. Overall, occurrence of A. marginale in blood and tick samples was found to be 65.21% and 8.1% respectively. Species-wise occurrence in blood samples of goats were 71.11% followed by sheep 68.31% and cattle 50%. Specie-wise occurrence of A. marginale in tick samples of cattle were 12.5% followed by goats 6.89%. The obtained sequence showed similarity with A. marginale reported from Kenya and USA. We report the first PCR based detection of A. marginale infection in blood samples and in R. sanguineus ticks of goats simultaneously.

RA92A recombinant protein as immunogen to protect cattle against tick challenge in Brazil and Uganda

In this study, the recombinant gut protein rRa92A produced in Pichia pastoris yeast cells was used to immunize cattle in two experiments, one in Brazil and the other in Uganda. In both experiments, the animals were intramuscularly (IM) injected with 200 µg of recombinant protein in Brazil on days 0, 30 and 51 and in Uganda on days 0, 30. Blood samples for sera separation were collected from different days in both experiments. These samples were analyzed by ELISAs. In Brazil, ticks collected from the animals during the experimental period were analyzed for biological parameters. At Uganda, blood was collected to assess blood parameters, clinical signs were recorded and adult tick (Rhipicephalus appendiculatus) counts were performed. All animals of the vaccinated groups were shown to produce antibodies, and it was not possible to detect an effect on Rhipicephalus microplus. All the clinical parameters were considered within the normal ranges for both the experimental and control groups in Uganda. Antibody absorbance was elevated after each immunization and remained high until the end of the experiments, remaining low in the control animals. The results of stall test carried out in Brazil using R. microplus tick showed efficacy of 21.95%. The rRa92A immunization trial experiments in Uganda showing a decrease of 55.2% in the number of engorged adult ticks, which was statistically significant (p<0.05). Assessment of the immunogenicity of Ra92A produced in the P. pastoris expression system in bovines is reported for the first time, and the protein acted as a concealed antigen.

Influence of agricultural extension activities on tick control among cattle on family dairy farms in the southeast Brazil

The aim of the present study was to evaluate the resistance of tick populations on 16 family farms that were members of the agricultural producers' cooperative of the São Pedro region of the state of São Paulo (COOPAMSP). Bioassays were conducted on nine commercial products in 2018 and 2019. Their active agents were as follows: deltamethrin, amitraz, cypermethrin + chlorpyrifos + citronella, cypermethrin + chlorpyrifos + fenthion, cypermethrin + chlorpyrifos + piperonyl butoxide, dichlorvos + chlorpyrifos, cypermethrin, chlorfenvinphos + dichlorvos, and ivermectin. On some farms, a larval packet test (LPT) was also performed. Overall, four acaricides presented mean efficacy greater than 89%, among which two were associations of pyrethroids + organophosphates and two were associations of organophosphates + organophosphates. Deltamethrin, cypermethrin and ivermectin presented mean efficacy lower than 50%. In the bioassays using the LPT, all five farms showed resistance to diazinon, while only one farm presented resistance to cypermethrin. The results were handed over to each farmer with appropriate guidance for treatments. This study demonstrated that the important points to be implemented related directly to use control strategies, based on direct assistance for farmers and diagnosis of tick population sensitivities.

Use of anti-tick drugs in dairy farms in the microregion of Alfenas, Minas Gerais, Brazil / Uso de carrapaticidas em fazendas leiteiras na microrregião de Alfenas, Minas Gerais, Brasil

Abstract Ectoparasitic infestation in dairy cattle, the most common being Rhipicephalus (Boophilus) microplus, causes significant loss in production. The control of ectoparasites often occurs incorrectly, resulting in resistance to the active ingredients and residues in milk. To understand of acaricide use in the microregion of Alfenas, Minas Gerais (Brazil), questionnaires were applied to the owners of 100 dairy farms in the region and were selected randomly. Dairy farms were allocated according to production scale: up to 150 liters/day, 151-400 liters/day and more than 400 liters/day. The interviewees were asked about production characteristics, acaricide management and active ingredients. The interview answers were subjected to descriptive analysis. Results showed that all properties, independent of production-scale, used acaricides. The most cited was: Cypermethrin Chlorpyrifos Citronellal (31%), Fluazuron (18.6%) and Fipronil (17%). Among the interviewed, 41,1% use drugs that have restrictions that are not allowed in legislation for use in lactating dairy cows (fluazuron, fipronil, ivermectin). 15% affirmed they weren't aware of the "withdrawal period" of medication and 73% change in the active ingredient used. In order to revert this antiparasitic drug's resistance situation and contamination of milk with drug residues, it is necessary to focus on the awareness of milk producers and training of labor.

Resumo A infestação por ectoparasitas em bovinos leiteiros, sendo o mais comum o Rhipicephalus (Boophilus) microplus, causa prejuízos significativos na produção. No entanto, o controle dos ectoparasitas geralmente ocorre incorretamente, resultando em resistência aos princípios ativos e presença de resíduos no leite. Para entender os padrões de uso de acaricidas na microrregião de Alfenas, Minas Gerais, Brasil, foram aplicados questionários aos proprietários de 100 fazendas leiteiras que foram classificadas de acordo com uma escala de produção: até 150 litros/dia, de 151 a 400 litros/dia e mais de 400 litros/dia. Os entrevistados foram questionados sobre características da produção, manejo do acaricida de gado e conhecimento sobre os princípios ativos. Todas as propriedades, independentemente da escala de produção, usavam acaricidas. Foram citados com maior frequência: Cipermetrina + Clorpirifós + Citronelal (31%), Fluazuron (18.6%) e Fipronil (17%). Entre os produtores entrevistados, 41,1 % fazem uso de drogas com restrição que não são atualmente permitidas na legislação para uso em vacas em lactação (fluazuron, fipronil, ivermectina). 15% dos produtores de leite afirmaram não estar cientes do "período de carência" dos medicamentos; outros relatam trocas constantes do princípio ativo utilizado. Para reverter a situação do uso indiscriminado de antiparasitários, é necessário focar na conscientização dos produtores de leite e na formação do trabalho.

Effects of essential oils on native and recombinant acetylcholinesterases of Rhipicephalus microplus / Efeito de óleos essenciais sobre acetilcolinesterases nativa e recombinante de Rhipicephalus microplus

Abstract This study reports the action of essential oils (EO) from five plants on the activity of native and recombinant acetylcholinesterases (AChE) from Rhipicephalus microplus. Enzyme activity of native susceptible AChE extract (S.AChE), native resistant AChE extract (R.AChE), and recombinant enzyme (rBmAChE1) was determined. An acetylcholinesterase inhibition test was used to verify the effect of the EO on enzyme activity. EO from Eucalyptus globulus, Citrus aurantifolia, Citrus aurantium var.dulcis inhibited the activity of S.AChE and R.AChE. Oils from the two Citrus species inhibited S.AChE and R.AChE in a similar way while showing greater inhibition on R.AChE. The oil from E. globulus inhibited native AChE, but no difference was observed between the S.AChE and R.AChE; however, 71% inhibition for the rBmAChE1 was recorded. Mentha piperita oil also inhibited S.AChE and R.AChE, but there was significant inhibition at the highest concentration tested. Cymbopogon winterianus oil did not inhibit AChE. Further studies are warranted with the oils from the two Citrus species that inhibited R.AChE because of the problem with R. microplus resistant to organophosphates, which target AChE. C. winterianus oil can be used against R. microplus populations that are resistant to organophosphates because its acaricidal properties act by mechanism(s) other than AChE inhibition.

Resumo Este estudo relata a ação de óleos essenciais de cinco plantas na atividade de acetilcolinesterases (AChE) nativas e recombinantes de Rhipicephalus microplus. A atividade enzimática do extrato de acetilcolinesterase nativa suscetível (S.AChE) e resistente (R.AChE) e da enzima recombinante (rBmAChE1) foi determinada. Um teste de inibição da AChE foi utilizado, para verificar o efeito dos óleos essenciais sobre a atividade enzimática. Óleos essenciais de Eucalyptus globulus, Citrus aurantifolia, Citrus aurantium var. dulcis inibiram a atividade de S.AChE e R.AChE. Os óleos das duas espécies de Citrus inibiram S.AChE e R.AChE de maneira semelhante, mas mostraram maior inibição sobre R.AChE. O óleo de E. globulus inibiu a AChE nativa, mas sem diferença entre a S.AChE e a R.AChE; no entanto, 71% de inibição para rBmAChE1 foi observada. O óleo de Mentha piperita também inibiu S.AChE e R.AChE, mas houve inibição significativa apenas nas concentrações mais altas testadas. O óleo de Cymbopogon winterianus não inibiu a AChE. Estudos adicionais são necessários com os óleos das duas espécies de Citrus que inibiram a R.AchE, devido ao problema de R. microplus resistente aos organofosforados ter como alvo AChE. O óleo de C. winterianus pode ser usado contra populações de R. microplus, que são resistentes a organofosforados, porque suas propriedades acaricidas agem por mecanismos diferentes.

Effects of climate changes on the distribution of Rhipicephalus microplus in China / 中国血吸虫病防治杂志

Objective To identify the environmental factors affecting the geographical distribution of Rhipicephalus microplus in China, and to examine the impact of climate changes on the distribution of R. microplus in China. Methods The national and international publications pertaining to the geographical distribution of R. microplus in China were retrieved, and the geographical location was extracted. The suitable habitats of R. microplus and the dominant environmental factors affecting the distribution of suitable habitats of R. microplus were predicted in China based on the geographical data and environmental variables using the ArcGIS 10.7 software and the maximum entropy model. Results Among the main climatic factors affecting the geographical distribution of R. microplus in China, the factors contributing more than 10% to the suitable habitats of R. microplus mainly include the annual mean precipitation (38.2%), the average temperature of the coldest quarter (28.4%) and the precipitation of the driest month (14.2%). The current suitable habitats of R. microplus were mainly found in southern China, and the high-, medium- and low-suitable areas accounted for 8.6%, 13.1% and 10.5% of the total land area of China, respectively. The suitable habitats of R. microplus were predicted to increase by 399 800 km2 in China using the maximum entropy model under the RCP 4.5 emissions scenario in 2070, and the emerging suitable habitats were mainly distributed in Gansu Province, Ningxia Hui Autonomous Region, Qinghai Province, Hebei Province, Shaanxi Province, Liaoning Province, Inner Mongolia Autonomous Region, Shandong Province, Sichuan Province and Tibeten Autonomous Region. In addition, the suitable habitats of R. microplus were predicted to show an overall expansion towards northward from present to 2070. Conclusions Climate changes affect the distribution of suitable habitats of R. microplus in China, and annual mean precipitation may be a key factor affecting the distribution of suitable habitats of R. microplus.

Anticholinesterase and acaricidal activities of steroids isolated from Trianthema portulacastrum L. against Rhipicephalus annulatus tick

The anticholinesterase and acaricidal activities of two plants of family Aizoaceae; Trianthema portulacastrum L.and Aizoon canariensis L. against Rhipicephalus annulatus tick were performed. Acaricidal activity was evaluatedusing adult and larval immersion tests of different concentrations (12.5, 25, 50, 100, and 150 mg/ml). Antiacetylcholinesterase activity of plant extracts and isolated compounds were performed spectrophotometrically usingdifferent concentrations (0.25, 0.5, and 1 mg/ml). Trianthema portulacastrum crude hydroalcoholic (CH) extractshowed 100% adult and larval mortality, while A. canariensis L. showed only 20% and 25%, respectively (p ≥ 0.05).The bioassay-guided fractionation of T. portulacastrum hydroalcoholic extract was performed for the acaricidalactivity and both n-hexane fraction and the unsaponifiable matter (USM) retained a significant activity in immersiontests. Its column chromatography (CC) led to the isolation of a β-sitosterol (1)-stigmasterol (2) mixture (1:1). Ethylacetate (EA) fraction showed 70% adult mortality and the compound 20-hydroxyecdysone (3) was isolated as a majorcompound. The hydroalcoholic extract of T. portulacastrum, hexane fraction, and 20-hydroxyecdysone (3) producedthe most potent inhibitory effect on acetylcholinesterase (AChE). In conclusion, T. portulacastrum L. containssecondary metabolites with acaricidal activities that provide promising natural products for controlling bovine tick.These acaricidal effects may be mediated, at least in part, via AChE inhibitory activities.

Ehrlichiosis monocítica canina en la provincia de Entre Ríos, Argentina: confirmación molecular de casos en la ciudad de Concordia / Canine monocytic ehrlichiosis in Entre Ríos province, Argentina: molecular confirmation of cases in Concordia city

Resumen El objetivo del siguiente trabajo fue confirmar la presencia de Ehrlichia canis por diagnóstico molecular, a partir de muestras de perros con diagnósticos presuntivos, oriundos de la ciudad de Concordia, provincia de Entre Ríos. ADN fue extraído de 14 muestras de sangre de perros con diagnóstico presuntivo de EMC. Para la detección de ADN deE. canis se amplificó un fragmento del gen dsb, específico de este género, y su confirmación específica se realizó mediante secuenciación. Doce de las 14 muestras mostraron bandas del tamaño esperado. Las secuencias obtenidas mostraron un 98-100% de identidad con secuencias registradas en GenBank para E. canis. Además, se amplificó un fragmento del gen ARNr 16S mitocondrial de garrapatas obtenidas de un perro positivo. Las secuencias demostraron que corresponden a R. sanguineus sensu stricto (linaje templado). En este estudio se confirma la presencia de E. canis en la ciudad de Concordia, Entre Ríos, resultando en una alerta para los médicos veterinarios de la región, a fin de incentivar estrategias de prevención de la enfermedad y control del vector.

Abstract The aim of this work was to confirm the presence of Ehrlichia canis in blood samples of dogs from Concordia, Entre Ríos Province, Argentina. DNA was extracted in 14 blood samples of dogs with presumptive diagnosis of CME. A PCR protocol targeting dsb gene, specific for genus Ehrlichia was carried out for detection and species confirmation was carried out by sequencing. Twelve out of 14 samples shown bands of the expected size. The obtained sequences revealed 98-100% identity with E. canis sequences registered in GenBank. Moreover, ticks were retrieved from an E. canis positive dog and a fragment of mitochondrial ARNr 16S gene was amplified. The obtained sequences were identified as R. sanguineus sensu stricto (temperate linage). This work confirmed the presence of E. canis in Concordia city, Entre Ríos province resulting in an alert for veterinary clinicians in this region aiming to encourage prevention strategies of this disease and vector control.

Distribución anatómica de Rhipicephalus sanguineus sensu stricto (Acari: Ixodidae) sobre caninos domésticos / Anatomical distribution of Rhipicephalus sanguineus sensu stricto (Acari: Ixodidae) on dogs

Resumen En este trabajo se realizó el estudio de la distribución anatómica de los diferentes estadios de Rhipicephalus sanguineus sensu stricto sobre sus hospedadores principales, los caninos. El mismo se basó en muestreos mensuales durante tres años en la ciudad de Esperanza, Santa Fe, Argentina. Para determinar la distribución de los diferentes estadios parasitarios se dividió el cuerpo en regiones y se colectaron todos los especímenes en cada una de ellas. Las larvas tuvieron como preferencia las zonas de cabeza seguido de los espacios interdigitales, orejas y abdomen; las ninfas tuvieron preferencia por las orejas y abdomen, y otras zonas de preferencia fueron cabeza y espacios interdigitales; los adultos (machos y hembras) prefirieron localizarse en las orejas, cuello y lomo.

Abstract The anatomical distribution of the different stages of Rhipicephalus sanguineussensu stricto on canines was analyzed. Data was collected from dogs on monthly sampling during three years in the city of Esperanza, Santa Fe, Argentina. To determine the distribution of the different parasitic stages, the body surface was divided into regions and all specimens were counted in each of them. Larvae had preference for the head followed by the interdigital spaces, ears and abdomen, nymphs were mainly found on ears and abdomen, and other areas of preference were head and interdigital spaces; the adults (males and females) preferred the ears, neck and back.

Detection of tick-borne rickettsial pathogens in naturally infected dogs and dog-associated ticks in Medellin, Colombia / Detecção de patógenos rickettsiais transmitidos por carrapatos em cães naturalmente infectados e carrapatos associados a cães em Medellin, Colômbia

Abstract Tick-borne rickettsial pathogens (TBRP) are important causes of infections in both dogs and humans. Dogs play an important role as a biological host for several tick species and can serve as sentinels for rickettsial infections. Our aim was to determine the presence of TBRP in dogs and in dog-associated ticks and their potential risk to human diseases in Medellin, Colombia. DNA for E. canis (16S rRNA and dsb) and A. platys (groEl) was detected in 17.6% (53/300) and 2.6% (8/300) of dogs, respectively. Antibodies against Ehrlichia spp. 82 (27.3%) and Anaplasma spp. 8 (2.6%) were detected in dogs. Antibody reactivity against both agents were found in 16 dogs (5.3%). Eight dogs showed antibody for Rickettsia spp. with titers that suggest 3 of them had a probable exposure to R. parkeri. Rhipicephalus sanguineus s.l. (178/193) was the main tick in dogs, followed by R. microplus (15/193). The minimum infection rates (MIR) in R. sanguineus were 11.8% for E. canis and 3.4% for A. platys. E. canis and A. platys are the main TBRP infecting dogs and ticks and R. sanguineus s.l. is likely involved in the transmission of both agents. Interestingly, we found serological evidence of exposure in dogs for spotted fever group rickettsiae.

Resumo As riquétsias transmitidas por carrapatos (RTC) são causas importantes de infecção em cães e humanos. Os cães exercem um papel essencial como hospedeiros biológicos para diversas espécies de carrapatos, assim como podem ser úteis como sentinelas de infecções por riquétsias. O intuito deste estudo foi determinar a presença de RTC em cães, assim como em seus carrapatos, para determinar o risco potencial de doença humana em Medellín, Colômbia. DNA de Ehrlichia canis (16S rRNA e dsb) e Anaplasma platys (groEl) foi detectado em 17,6% (53/300) e 2,6% (8/300) dos cães, respectivamente. Anticorpos contra Ehrlichia spp. (82; 27,3%) e Anaplasma spp. (8; 2,6%) foram detectados nos cães. Reatividade de anticorpos contra ambos patógenos (Ehrlichia e Anaplasma) foi detectada em 16 cães (5,3%). Oito animais apresentaram anticorpos contra Rickettsia spp., e 3 deles sugerem uma provável exposição a Rickettsia parkeri. Rhipicephalus sanguineus s.l. (178/193) foi a principal espécie de carrapatos, seguida de R. microplus (15/193). A taxa de infecção mínima em R. sanguineus foi 11,8% para E. canis e 3,4% para A. platys. E. canis e A. platys são as principais RTC que infectam cãese R. sanguineus s.l. provavelmente está envolvido na transmissão de ambos os agentes. É evidente, porém, a exposição sorológica dos cães a riquétsias do grupo da febre maculosa.

Rickettsial pathogens circulating in urban districts of Rio de Janeiro, without report of human Brazilian Spotted Fever / Circulação de patógenos riquetsiais em bairros urbanos do Rio de Janeiro sem relatos humanos da Febre Maculosa Brasileira

Abstract Spotted fever group rickettsioses are emerging diseases. In some of these diseases, domestic dogs act as sentinels. Canine serological studies have demonstrated that rickettsial dispersion is concentrated in rural areas, seroprevalence being higher where human rickettsioses are endemic. In Rio de Janeiro, the Atlantic forest vegetation has been devastated by urbanization. In this context, we aimed to detect Rickettsia spp. in urban areas of the West Zone of Rio de Janeiro. Sera from 130 dogs were tested by Indirect Immunofluorescence Assay, and ticks collected from these dogs were tested by polymerase chain reaction. We found the rate of serological reactions against R. rickettsii and R. parkeri in our study area to exceed those of rural and non-endemic areas, highlighting the importance of dogs as urban sentinels. The possibility of contact with opossums and capybaras increased the chances of exposure to Rickettsia spp., reinforcing the hypothetical link between the landscape and the rickettsial wild cycle. Rhipicephalus sanguineus sensu lato was the tick most frequently observed. PCR-positive samples showed similarity with R. rickettsii and R. felis, an emerging pathogen rarely reported from ticks. We observed that rickettsiae circulate in urban places and ticks from indoor environments, which may be involved in bacterial epidemiology.

Resumo Riquetsioses do Grupo da Febre Maculosa são doenças emergentes. Em algumas destas doenças, os cães domésticos agem como sentinelas. Estudos sorológicos caninos têm demonstrado que a dispersão de patógenos rickettsiais está concentrada em áreas rurais, sendo a soroprevalência maior onde as rickettsioses humanas são endêmicas. Na cidade do Rio de Janeiro, a vegetação de Mata Atlântica vem sendo devastada pela urbanização. Nesse contexto, objetivou-se detectar a presença de Rickettsia spp. em áreas urbanas da Zona Oeste do Rio de Janeiro. Amostras de soro obtidas de 130 cães foram testadas, utilizando-se a Imunofluorescência Indireta. Carrapatos coletados desses cães foram testados, utilizando-se a reação em cadeia da polimerase. Observou-se que as taxas de reações sorológicas contra R. rickettsii e R. parkeri nessa área de estudo excederam a prevalência das áreas rurais e não endêmicas, destacando-se a importância dos cães como sentinelas urbanos das rickettsioses. A possibilidade de contato com capivaras e gambás favoreceu a exposição à Rickettsia spp., reforçando a hipótese de ligação entre a paisagem local e o ciclo silvestre de transmissão riquetsial. O carrapato Rhipicephalus sanguineus sensu lato foi encontrado com maior frequência. Amostras com positividade pela PCR mostraram similaridade com R. rickettsii e R. felis, um patógeno emergente raramente descrito em carrapatos. Observou-se circulação riquetsial em áreas urbanas e em carrapatos obtidos do ambiente doméstico, os quais podem estar envolvidos na epidemiologia dessas bactérias.

Survey of protozoan vector-borne diseases in dogs from Atlantic Rainforest fragment around Billings Dam, São Paulo, Brazil / Levantamento de protozoários transmitidos por vetores em cães de um fragmento de Mata Atlântica nos arredores da Barragem Billings, São Paulo, Brasil

ABSTRACT: Vector-borne diseases are currently one of the biggest public health concerns worldwide. Dogs, being the closest companion animals to humans, are considered the main reservoir of some of these diseases in the urban environment. Therefore, the study of the disease behavior in dogs can help to understand the disease affecting human health. Serological and molecular diagnoses of Babesia vogeli, Rangelia vitalli, Leishmania infantum, and other trypanosomatids, were performed by immunochromatographic and PCR assays, respectively, on dogs in a dog shelter located in an Atlantic Forest fragment near the Billings Dam, São Bernardo do Campo, São Paulo-Brazil. Our molecular diagnostic results showed a high prevalence of Babesia vogeli, at 20.9% (17/81). No other protozoan was detected in any of the tests. Determining the prevalence of major vector-borne diseases is essential to establish preventive and control measures for zoonotic diseases in animals kept in shelters, in order to minimize the impact of vector-borne diseases on animal health.

RESUMO: As doenças transmitidas por vetores são atualmente um dos maiores problemas de saúde pública. Os cães, sendo os animais de companhia mais próximos dos seres humanos, são considerados os principais reservatórios de algumas dessas doenças no ambiente urbano, e o estudo de seu comportamento em cães ajuda a entender a doença como um todo na saúde humana. Diagnósticos sorológicos e moleculares de Babesia vogeli, Rangelia vitalli, Leishmania infantum e outros tripanossomatídeos, em um abrigo para cães localizado em um fragmento da Mata Atlântica próximo à Barragem Billings, São Bernardo do Campo, São Paulo, Brasil. Foram realizadas sorologias e diagnósticos moleculares, no ensaio de PCR foram utilizados marcadores moleculares de oligonucleotídeos específicos para alguns protozoários de importância na saúde animal, como Babesia vogeli, Rangelia vitalli, Leishmania infantum e outros tripanossomatídeos. Nossos resultados de diagnóstico molecular mostraram uma alta prevalência de 20,9% (17/81) de Babesia vogeli. Nenhum outro protozoário foi detectado em nenhum dos testes. A determinação da prevalência das principais doenças transmitidas por vetores é essencial para estabelecer medidas preventivas e de controle de doenças zoonóticas em animais mantidos em abrigos. Essas medidas devem ser propostas para minimizar o impacto de doenças transmitidas por vetores na saúde animal.

Acaricidal potential of volatile oils from Croton species on Rhipicephalus microplus

ABSTRACT The objective of this study was to evaluate the acaricidal activity of the volatile oils of three species of Croton, Euphorbiaceae, against the cattle tick Rhipicephalus microplus. The volatile oils were obtained by hydrodistillation, analyzed by GC-MS and GC-FID and their acaricidal activity was evaluated by the larval packet test and adult immersion test. The volatile oils from Croton conduplicatus Kunth, Croton pulegiodorus Baill., and two different collections of Croton grewioides Baill. (CG1 and CG2) showed eucalyptol (24.09%), p-cymene (23.13%) and methyl chavicol (83.59% and 95.38%) as the major compounds, respectively. All the volatile oils tested in this study showed efficacy against larvae and engorged females of Rhipicephalus microplus. Therefore, Croton pulegiodorus volatile oil is promising for a potential acaricidal formulation because of the best activity against both stages of the cattle tick.

Primer reporte de un caso de ehrlichiosis monocítica canina en la provincia de Santa Fe, Argentina

La ehrlichiosis monocitica canina (EMC) es una enfermedad causada por la bacteria Ehrlichia canis, de distribución mundial, alta mortalidad en caninos doméstico y síntomas inespecíficos, lo que dificulta su diagnóstico clínico. Ehrlichia canis es transmitida por la garrapata Rhipicephalus sanguineus sensu lato a un hospedador, en Argentina se reconocen dos linajes (tropical y sensu stricto) de dicha especie. El objetivo del presente trabajo es reportar el primer caso confirmado de EMC por E. canis en un canino de la ciudad de Rafaela, Santa Fe, área endémica de R. sanguineus s.s. El 18/02/2019 llegó a la consulta privada un canino con síntomas inespecíficos como hipertermia tarde/noche, depresión, letargia, aplasia, inapetencia y pérdida de peso; más antecedente de parasitismo por garrapatas. La mascota presentaba anemia leve (4.730.000/mm³), enzimas hepáticas aumentadas (AST/ASA/GOT=72 U/l) y esplenomegalia. El test serológico in vitro y PCR para amplificar ADN E. canis fueron positivos, por lo que la mascota recibe tratamiento para EMC con doxiciclina 10 mg/kg/día durante 30 días, antiinflamatorios durante 5 días y protector hepático. A los 60 días de iniciado el tratamiento la mascota recuperó su peso normal y a los 120 días se realiza PCR como monitoreo de la eficacia del tratamiento dando resultado negativo.

Canine monocytic ehrlichiosis (CME) is a disease caused by Ehrlichia canis bacteria. It has a globally distributed and cause high mortality in domestic canines with nonspecific symptoms, which makes clinical diagnosis difficult. Eherlichia canis is transmitted to a host by the tick Rhipicephalus sanguineus sensu lato. In Argentina two lineages of this species are recognized (tropical and sensu stricto). The objective of this work is to report the first confirmed case of CME by E. canis in endemic area of R. sanguineus s.s from Rafaela, Santa Fe. On February 2, 2019 a canine arrived at the private clinic with non-specific symptoms such as late / night hyperthermia, depression, lethargy, aplasia, loss of appetite and weight loss, as well as, antecedent of tick parasitism. The pet had mild anemia (4,730,000/ m³), increased liver enzymes (AST/ASA/GOT = 72 U/l) and splenomegaly. The in vitro serological test and PCR to amplify E. canis DNA were positive, so the dog received treatment for CME with doxycycline 10 mg/kg/day for 30 days, anti-inflammatory for 5 days and liver protector. After 60 days of starting the treatment, the animal regained its normal weight and after 120 days the PCR have given negative result, checking the effectiveness of the treatment.

Biocidal potential of Eugenia pyriformis essential oil in the control of Rhipicephalus (Boophilus) microplus in the free-living cycle / Potencial biocida do óleo essencial de Eugenia pyriformis Cambess no controle de Rhipicephalus (Boophilus) microplus no ciclo de vida livre

Brazil has one of the largest commercial cattle herds in the world, which naturally coexist with an enormous number of parasitic species. Southern cattle tick, Rhipicephalus (Boophilus) microplus, is among these species, interfering with animal productivity and causing losses to the beef and dairy cattle sector. The use of chemical acaricides in the control of this mite has resulted in the emergence of resistant populations. In this sense, alternative control measures using plants as sources of botanical acaricides have shown to be effective. Eugenia pyriformis Cambess is a Brazilian plant with antioxidant and antimicrobial activity; however, there are no reports on its acaricidal activity in the literature. The present study aimed to evaluate the acaricidal and larvicidal potential of E. pyriformis leaf essential oil (EO) on southern cattle tick at different stages of the reproductive cycle. E. pyriformis leaves were collected and dried, and had their EO extracted by hydrodistillation (3h) using a modified Clevenger apparatus. Chemical analysis was performed by gas chromatography coupled with mass spectrometry (GC/MS), and 32 compounds belonging to the sesquiterpene class were identified: hydrocarbons (17.98%) and oxygenated forms (81.96%), with spathulenol (43.65%) and caryophyllene oxide (12.17%) as the most common. The EO was evaluated by the Adult Immersion Test at the concentrations (500.00 to 3.12mg/mL) in which the following parameters were measured: mortality of females (%), hatchability of eggs (%), and product efficiency (%). Larvae were assessed by the Larval Packet Test at concentrations ranging from 25.00 to 0.00004mg/mL. Lethal concentrations (LC) required for killing 50 and 99.9% of adult females and larvae were determined using Probit analysis. LC50 and LC99.9 of EO were 0.06 and 24.60mg/mL and 1,208.80 and 2,538mg/mL for larvae and adult females, respectively. Action of the EO in the free-living cycle of R. (B.) microplus larvae was another parameter assessed. To this end, the larvae were deposited in pots containing Brachiaria decumbens and, after migration to the leaf apex, a solution containing LC99.9 (24.60mg/mL) of the EO was sprayed. After 24h, 72.25% of the larvae had died, indicating stability of the EO when subjected to uncontrolled temperature and humidity conditions. The mechanism of action through which the EO killed the larvae and adult females was investigated by the Bioautographic Method, which showed inhibition of 3.15mg/mL of the EO on the acetylcholinesterase (AChE) enzyme. The results found in the present experiment indicate that E. pyriformis essential oil is an alternative in the control of southern cattle tick in the larval (parasitic) and free-living cycle (non-parasitic) stages under field conditions.(AU)

O Brasil dispõe de um dos maiores rebanhos bovinos comerciais do mundo, sendo natural que junto a esse rebanho, coexista uma enorme quantidade de espécies parasitárias; dentre estes o carrapato Rhipicephalus (Boophilus) microplus que interfere na produtividade animal, causando prejuízos à pecuária de corte e leite. A utilização de acaricidas químicos no controle deste ácaro tem causado o surgimento de populações resistentes e neste sentido, controles alternativos utilizando plantas como fontes de acaricidas botânicos têm se mostrado eficazes. Eugenia pyriformis Cambess é uma planta brasileira com atividades antioxidante e antimicrobiana, entretanto não há relatos da atividade acaricida. O objetivo do presente estudo consistiu na avaliação do potencial acaricida e larvicida do óleo essencial das folhas de E. pyriformis sobre o carrapato bovino nos diferentes estágios do ciclo reprodutivo. As folhas foram coletadas, secas e o OE extraído por hidrodestilação (3 horas) em aparelho Clevenger modificado. A análise química foi realizada por cromatografia gasosa acoplada à espectrometria de massas (CG/EM) sendo identificados 32 compostos, pertencentes à classe sesquiterpenos: hidrocarbonetos (17.98%) e oxigenados (81.96%); tendo como majoritários o spathulenol (43,65%) e caryophylene oxide (12,17%). O OE foi avaliado pelo teste de imersão de adultos nas concentrações (500,00 a 3,12mg/mL) onde foram mensurados os parâmetros: mortalidade das fêmeas (%), eclodibilidade dos ovos (%) e eficiência do produto (%). As larvas foram avaliadas pelo teste de imersão larval (Larval Packet Test) nas concentrações que variaram de 25,00 a 0,00004mg/mL. Foram determinadas as concentrações letais (CLs) necessárias para matar 50 e 99,9% das fêmeas adultas e das larvas utilizando a análise de Probitos. As CL50 e CL99,9 do OE foram (0,06 e 24,60mg/mL) para as larvas e (1.208,80 e 2.538mg/mL) para as fêmeas adultas, respectivamente. Outro parâmetro avaliado em nossa pesquisa foi mensurar a ação do OE no ciclo de vida livre das larvas de R.(B.) microplus; onde as larvas foram depositadas em vasos com Brachiaria decumbens e após migração destas para o ápice das folhas, foi aspergido solução contendo a CL99,9 (24,60mg/mL) do OE. Após 24 horas, 72,25% das larvas morreram indicando que houve estabilidade do OE quando submetido a condições de temperatura e umidade não controladas. O mecanismo de ação pelo qual o OE matou as larvas e fêmeas adultas foi investigado pelo método bioautográfico, indicando uma inibição de 3,15mg/mL do óleo essencial sobre a enzima acetilcolinesterase (AChE). Os resultados encontrados no presente experimento indicaram que o óleo essencial de E. pyriformis é uma alternativa no controle do carrapato bovino no estágio larval (parasitário) e no ciclo de vida livre (estágio não parasitário) em condições de campo.(AU)

Chemical composition and acaricidal activity of Ocotea notata (Lauraceae), an endemic species from Brazil, against the cattle tick Rhipicephalus microplus / Composición química y actividad acaricida de Ocotea notata (Lauraceae), una especie endémica de Brasil, contra la garrapata del ganado Rhipicephalus microplus

Rhipicephalus microplus, is one parasites that cause severe productivity losses in the cattle industry of Brazil and shows increasing resistance to conventional pesticides. This research aims to study the chemical composition, and acaricidal activity of the essential oil from Ocotea notata leaves, a brazilian endemic species, against R. microplus. The effect on R. microplus engorged adult females was evaluated using the immersion test. The oil reduced the survival by 90% after incubation for 15 days and there was 100% reduction for posture inhibition and reproductive capacity. These results suggest that the O. notata essential oil has activity on the R. microplus.

Rhipicephalus microplus, es un parásito que causa graves pérdidas de productividad en la industria ganadera de Brasil y muestra una creciente resistencia a los pesticidas convencionales. Esta investigación tiene como objetivo estudiar la composición química y la actividad acaricida del aceite esencial de las hojas de Ocotea notata, una especie endémica brasileña, contra R. microplus. El efecto sobre las hembras adultas engordadas de R. microplus se evaluó mediante la prueba de inmersión. El aceite redujo la supervivencia en 90% después de la incubación durante 15 días y hubo una reducción del 100% para la inhibición de la postura y la capacidad reproductiva. Estos resultados sugieren que el aceite esencial de O. notata tiene actividad contra R. microplus.

Comparative Acaricidal Bioefficacy Of Spilanthes Acmella And Calotropis Procera Of Eastern Himalayan Region Against Cattle Tick

In this study, relative toxicity of Spilanthes acmella and Calotropis procera wasevaluated against adults and larvae of Rhipicephalus (Boophilus) microplus. The aerial part ofboth plants materials were collected from Eastern Himalayan Region (West Bengal) of India.Plant materials were washed, shade dried, coarsely ground, methanol extracted and dried byrotary evaporator and collected proper yield of extracts. The crude methanolic extracts werefurther fractionated using solvents (hexane, ethyl acetate, chloroform) of different polarity andfinally aqueous fraction was collected and dried. Methanolic crude extracts and their fractions(hexane, ethyl acetate, chloroform and aqueous) concentrations of both the plants weretested against the engorged adult females and cultured larvae of Rhipicephalus (Boophilus)microplus. The bioefficacy observations are shown in table 3 and mentioned LC50, LC90 andtheir related statistics. Adult and larval stages were significantly affected by the chloroformextract of both the plants selected and observed the most potent with LC50 50.22 and 13.86mg/ml of Calotropis procera and LC50 60.94 and 25.82 mg/ml of Spilanthes acmella.

In vivo effect of diflubenzuron, administered via mineral salt supplementation, against Haematobia irritans and Rhipicephalus microplus parasitizing cattle / Efeito in vivo do diflubenzuron, administrado via sal mineral, contra Haematobia irritans e Rhipicephalus microplus parasitando bovinos

Abstract This study involved two field trials with the aim of evaluating the efficacy of diflubenzuron, via mineral supplementation, against Haematobia irritans parasitizing cattle. Concomitantly with the main trial, a stall test was conducted to ascertain the effects of a different formulation with the same active ingredient against Rhipicephalus microplus, along with the action of diflubenzuron on the reproductive parameters of R. microplusfemales that had naturally detached from cattle. Against H. irritans, it was observed that the efficacy indexes fordiflubenzuron were low (≤ 31.3% or 44.6%) or null (0.0%) throughout the study. The anti- R. microplus efficacy of diflubenzuron, at weekly intervals, ranged from 0.0 to 13.7% over the entire experimental period. Null efficacy (0.0%) was registered for diflubenzuron in relation to the reproductive parameters of R. microplusfemales that had naturally detached from cattle. The different diflubenzuron formulations, administered via mineral salt supplementation, did not show satisfactory efficacy indexes against H. irritans and R. microplus parasitizing cattle, within the experimental design of the present study. In addition, this agent did not present any deleterious effects on the reproductive parameters of R. microplus females.

Resumo O objetivo deste estudo foi avaliar a eficácia do diflubenzuron, administrado via suplementação mineral, contra Haematobia irritans parasitando bovinos, em dois testes à campo. Concomitantemente, foi realizado testes em estábulo para determinar os efeitos de uma formulação diferente, com o mesmo princípio ativo, contra Rhipicephalus microplus , bem como a ação do diflubenzuron nos parâmetros reprodutivos de fêmeas de R. microplus recolhidas após desprendimento natural do hospedeiro bovino. Contra H. irritans, foi observado que foram baixos (≤ 31,3% ou 44,6%) ou nulos (0,0%) os índices de eficácia do diflubenzuron. A eficácia anti-R. microplus do diflubenzuron, observada em intervalos semanais, variaram de 0,0% a 13,7% durante todo o período experimental. Com relação aos parâmetros reprodutivos das fêmeas de R. microplus recolhidas, foi observada eficácia nula (0,0%) para o diflubenzuron. Conclui-se que as diferentes formulações administradas via sal mineral no atual estudo, contra H. irritans e R. microplus parasitando bovinos, não apresentaram eficácia satisfatória. Este agente também não mostrou efeito deletério sobre os parâmetros reprodutivos de fêmeas de R. microplus.