31 research outputs found
Occurrence of the Oribatid Mite Trhypochthoniellus longisetus longisetus (Acari: Trhypochthoniidae) on Tilapia (Oreochromis niloticus).
Mites as parasites infesting fish have been described in a few case reports involving Histiostoma anguillarum, H. papillata, and Schwiebea estradai. We describe the unexpected occurrence of oribatid mites of the genus Trhypochthoniellus on farmed tilapia Oreochromis niloticus. The fish had mites on the skin, fins, and gills, as well as in the mouth. The morphological characteristics of the mites, observed by optical and scanning electron microscopy, were consistent with those described for T. longisetus longisetus. All stages of development were observed, suggesting that the mites were able to actively reproduce on fis
Desarrollo de métodos de bioensayo con garrapatas aplicados a la detección de potenciales bioplaguicidas botánicos
Este capítulo trata de comparar la metodología usada de forma rutinaria para evaluar la actividad de agentes garrapaticidas, no adaptada a la evaluación de extractos y productos naturales, desarrolladas en el contexto del proyecto CYTED P307AC0512 específicas para la aplicación de extractos y productos de origen botánico. En primer lugar se describen los métodos utilizados y descritos en la bibliografía y después se describe la metodología desarrollada y algunos resultados obtenidos como ejemplosPublishe
Babesia microti-like en un perro inmunocompetente
La babesiosis canina es una enfermedad infecciosa de distribución mundial causada por parásitos intraeritrocitarios transmitidos por garrapatas. Si bien ha sido tradicionalmente asumido que sólo dos de las 73 especies de babesias identificadas causan enfermedad en la especie canina, Babesia canis y Babesia gibsoni, recientes publicaciones demuestran que una tercera especie (Babesia microti-like) también puede parasitar a perros. Este último parásito, genéticamente relacionado con Babesia microti, es el origen de una enfermedad endémica entre la población canina del noroeste de España. Este trabajo presenta un caso no experimental de esta forma de Babesia microti-like en un perro cocker spaniel de 9 años, sin antecedentes de inmunodeficiencia ni de esplenectomía, que se presenta en la clínica veterinaria con signos de hipertermia, hemoglobinuria, escalofríos y apatía. Una muy intensa parasitemia (24%), junto con trombopenia y una acusada anemia hemolítica regenerativa fueron los hallazgos más caractéristicos. En la extensión de sangre periférica se visualizaron múltiples merozoitos intraeritrocitarios (parasitemia de un 24%) de pequeño tamaño (1-2 um) y presentación única en cada hematíe. Cuarenta y ocho horas después del comienzo de los síntomas, y tras tratamiento específico con dipropionato de imidocarb el perro evolucionó hacia la curación
Antiparasitic properties of cantharidin and the blister beetle berberomeloe majalis (Coleoptera: Meloidae)
Cantharidin (CTD) is a toxic monoterpene produced by blister beetles (Fam. Meloidae) as a chemical defense against predators. Although CTD is highly poisonous to many predator species, some have evolved the ability to feed on poisonous Meloidae, or otherwise beneficially use blister beetles. Great Bustards, Otis tarda, eat CTD-containing Berberomeloe majalis blister beetles, and it has been hypothesized that beetle consumption by these birds reduces parasite load (a case of self- medication). We examined this hypothesis by testing diverse organisms against CTD and extracts of B. majalis hemolymph and bodies. Our results show that all three preparations (CTD and extracts of B. majalis) were toxic to a protozoan (Trichomonas vaginalis), a nematode (Meloidogyne javanica), two insects (Myzus persicae and Rhopalosiphum padi) and a tick (Hyalomma lusitanicum). This not only supports the anti-parasitic hypothesis for beetle consumption, but suggests potential new roles for CTD, under certain conditions.This research was funded by MINECO/FEDER, Spain, Grant no. CTQ2015-64049-C3-1-R; Ministerio de Economía y Competitividad, Spain (MINECO/FEDER), Grant no. CGL2017-87206-
Acaricidal and Repellent Effects of Essential Oils against Ticks: A Review
17 Pág.
Departamento de Reproducción AnimalTick control is a priority in order to prevent the transmission of vector-borne diseases. Industrial chemical acaricides and repellents have been the most efficient tools against hard ticks for a long time. However, the appearance of resistances has meant the declining effectiveness of the chemicals available on the market. The trend today is to develop alternative control methods using natural products to replace nonefficient pesticides and to preserve the efficient ones, hoping to delay resistance development. Traditional in vitro evaluation of acaricidal activity or resistance to synthetic pesticides have been reviewed and they mainly focus on just one species, the one host tick (Rhipicephalus (Boophilus) microplus (Acari: Ixodidae)). Recent reports have called for the standardization of natural product components, extraction techniques, and experimental design to fully discover their acaricidal potential. This study reviews the main variables used in the bibliography about the efficiency of natural products against ticks, and it proposes a unification of variables relating to ticks, practical development of bioassays, and estimation of ixodicidal activity.This study was funded by Villamagna S.A.Peer reviewe
Sarcoptes scabiei infestation does not alter the stability of ectoparasite communities
Endoparasitosis más importantes de los équidos : Programas de control
El establecimiento de programas de control de los principales procesos parasitarios debe estar contemplado en el manejo de toda explotación equina. La influencia en el desarrollo de los parásitos de factores como la edad de los animales, condiciones medioambientales y sistemas de explotación exige una programación adaptada a las distintas circunstacias (figura 1). En general, el control es imprenscindible en animales de pastoreo, con especial énfasis en las yeguas de vientre y en los potros, valorándose su necesidad en équidos en estabulación. El control estará basado en acciones integradas por medidas de manejo y terapéuticas. La forma más adecuada y rentable de establecer un tratamiento farmacológico es la evaluación previa mediante monitorización de la carga parasitaria y el establecimiento de medidas adaptadas a las necesidades concretas y a la epidemiología de los procesos en la zona. En los casos en los que la monitorización no sea posible pueden adoptarse sistemas más estadísticos como la aplicación de antiparasitarios de forma estacional o a intervalos fijos. Sea cual fuere el método elegido, el éxito de control dependerá, no tanto de la eliminación de los parásitos de su hospedador, como del establecimiento de medidas de control que eviten el contagio
Valorization of essential oils from two populations (wild and commercial) of Geranium macrorrhizum L.
The insecticidal and acaricidal effects of the essential oils (EO) from two populations of Geranium macrorrhizum L (ornamental variety Bevan, VB and wild population from Hungary, GH) have been studied against several insect pests of economic importance in agriculture (Spodoptera littoralis, Myzus persicae and Rhopalosiphum padi), and the hard tick Hyalomma lusitanicum. The oil from the wild population (GH) was characterized by its content in β-elemenone (30.53%), thymol (18.52%) and germacrone (15.54%), while the oil from the commercial variety (VB) had linalool (26.45%) and linalyl acetate (25.11%) as major components. S.litoralis and R. padi were significantly affected by the wild population oil (GH-EO). The oil from the commercial variety VB was less effective against insects. The ixodicidal effects of these oils were strong, being the wild population (GH-EO) the most effective. To correlate the composition of these oils with their activity, the essential oil major components have been isolated (germacrone and β-elemenone) and tested (linalool, thymol, germacrone and β-elemenone). The insect antifeedant and ixodicidal effects of thymol and germacrone explained the bioactivity of the GH essential oil. Therefore, the wild variety of G. macrorrhizum has been selected for domestication given its potential as a source of bioactive extracts and metabolites.This work has been supported by grants CTQ2015-64049-C3-1-R and CTQ2015-64049-C3-3-R (MINECO/FEDER), Junta de Andalucía (Excellence Project P08-FQM-3596) and Villamagna SA. We thank R. Muñoz for technical assistance and J.M. Tercero for tick collection. The authors are also especially grateful to his Grace the Duke of Westminster.Peer reviewe
Acaricidal and Insect Antifeedant Effects of Essential Oils From Selected Aromatic Plants and Their Main Components
12 Pág.
Departamento de Reproducción AnimalThis work has demonstrated the ixodicidal and insect antifeedant effects of essential oils from 14 experimentally cultivated aromatic plants. The strong ixodicidal and antifeedant oils corresponded to Thymus zygis, Thymus vulgaris, Satureja montana, Oreganum virens, and Mentha suaveolens. The moderately active oils were from Lavandula angustifolia, Mentha piperita, Mentha spicata, Artemisa herba-alba, and Rosmarinus officinalis. The most effective larvicidal and antifeedant compounds were piperitenone oxide, carvacrol, piperitenone, and thymol, explaining the effects of the most active essential oils. The rest of the tested compounds were not ixodicidal or antifeedant. Therefore, the activity of moderately active oils cannot be explained by their main components (linalyl acetate, linalool, menthone, menthol, limonene, camphor, 1,8-cineole, p-cymene, α-pìnene, and carvone), suggesting synergistic effects. Considering the ixodicidal and antifeedant effects of these extracts, the plants have been ranked in relation to Thymus vulgare, a commercial biopesticide ingredient, for their potential as botanical pesticides. T. zygis, S. montana, and M. suaveolens ranked over T. vulgaris as ixodicidal agents and S. montana as insecticidal. Therefore, we propose the plant populations of S. montana, T. zygis, and M. suaveolens tested here for further development as biopesticide ingredients.This work has been supported by grants from ERASMUS+ no. 2018-1-FR01-KA202-047892, Biocontrol E Training (BET), and ERASMUS+ 600873-EPP-1-2018-1-ES-EPPKA2. European Hub on New Challenges in the Field of Essential Oils (EOHUB), PID2019-106222RB-C31, MCI, Spain, RTA 2014-00080-00-00, Spain, and the R+D contracts CSIC-Villamagna Estudio Biodirigido de Extractos Ixodicidas and UCM-Villamagna SL Investigación en torno al control de las garrapatas y al estado sanitario de la fauna silvestre.Peer reviewe