18 research outputs found
Ectoparasitos de cães no ambiente doméstico da vertente Caribe, Costa Rica
Reports on ectoparasites on dogs in Central America are scarce. The aim of this study was to identify flea, louse and tick species infesting dogs in home environments on the Caribbean slope of Costa Rica, and determine their frequency and coexistence. Ectoparasites were collected from dogs in 83 rural homes at five study sites. Specimens were identified and separated according to species. Fleas were the most common ectoparasite (G = 22,217, DF = 8, p = 0.004). Ctenocephalides felis and Pulex simulans were found in 83% and 55% of the homes with ectoparasites, respectively. Trichodectes canis (13%), Heterodoxus spiniger (10%), Rhipicephalus sanguineus (18%), Rhipicephalus (Boophilus) microplus (5%) and Amblyomma ovale (8%) were also present. More than one species was collected in most cases (66%), and the most common combination was C. felis and P. simulans (59% of homes with fleas). The high frequency of P. simulans emphasizes the need for adequate identification. This was the first study involving different ectoparasites of dogs in Costa Rica, as well as the first report of T. canis in this country. The relative frequency and coexistence of these ectoparasites in the home environment may have implications for animal and human health.Relatos de ectoparasitos em cĂŁes da AmĂ©rica Central sĂŁo escassos. O objetivo deste estudo foi identificar espĂ©cies de pulgas, piolhos e carrapatos que infestam os cĂŁes no ambiente domĂ©stico da vertente Caribe da Costa Rica, determinando sua frequĂȘncia e coexistĂȘncia. Foram coletados ectoparasitos de cĂŁes em 83 casas rurais de cinco sĂtios do estudo. Os indivĂduos foram separados e identificados. Os ectoparasitos mais comuns foram as pulgas (G = 22.217, DF = 8, p = 0.004). Ctenocephalides felis e Pulex simulans foram observados em 83% e 55% das moradias com ectoparasitos, respectivamente. Da mesma forma tambĂ©m foram observados Trichodectes canis (13%), Heterodoxus spiniger (10%), Rhipicephalus sanguineus (18%), Rhipicephalus (Boophilus) microplus (5%) e Amblyomma ovale (8%). Na maioria dos casos, mais de uma espĂ©cie foi achada (66%), sendo que a combinação mais comum foi C. felis e P. simulans (59% de moradias com pulgas). A frequĂȘncia alta de P. simulans ressalta a necessidade de sua adequada identificação. Este Ă© o primeiro estudo que envolve diferentes ectoparasitas de cĂŁes na Costa Rica, da mesma forma, Ă© o primeiro relato de T. canis no paĂs. A frequĂȘncia relativa e coexistĂȘncia destes ectoparasitos no ambiente domiciliar poderiam ter implicaçÔes na saĂșde animal e humana.Universidad de Costa Rica/[803-A8-127]/UCR/Costa Rica/[9-N-2008]/NeTropica/Costa RicaUCR::VicerrectorĂa de InvestigaciĂłn::Unidades de InvestigaciĂłn::Ciencias de la Salud::Centro de InvestigaciĂłn en Enfermedades Tropicales (CIET)UCR::VicerrectorĂa de InvestigaciĂłn::Unidades de InvestigaciĂłn::Ciencias BĂĄsicas::Centro de InvestigaciĂłn en Estructuras MicroscĂłpicas (CIEMIC)UCR::VicerrectorĂa de Docencia::Ciencias BĂĄsicas::Facultad de Ciencias::Escuela de BiologĂ
Flea Diversity as an Element for Persistence of Plague Bacteria in an East African Plague Focus
Plague is a flea-borne rodent-associated zoonotic disease that is caused by Yersinia pestis and characterized by long quiescent periods punctuated by rapidly spreading epidemics and epizootics. How plague bacteria persist during inter-epizootic periods is poorly understood, yet is important for predicting when and where epizootics are likely to occur and for designing interventions aimed at local elimination of the pathogen. Existing hypotheses of how Y. pestis is maintained within plague foci typically center on host abundance or diversity, but little attention has been paid to the importance of flea diversity in enzootic maintenance. Our study compares host and flea abundance and diversity along an elevation gradient that spans from low elevation sites outside of a plague focus in the West Nile region of Uganda (âŒ725â1160 m) to higher elevation sites within the focus (âŒ1380â1630 m). Based on a year of sampling, we showed that host abundance and diversity, as well as total flea abundance on hosts was similar between sites inside compared with outside the plague focus. By contrast, flea diversity was significantly higher inside the focus than outside. Our study highlights the importance of considering flea diversity in models of Y. pestis persistence
Composition and Function of Haemolymphatic Tissues in the European Common Shrew
BACKGROUND: Studies of wild animals responding to their native parasites are essential if we are to understand how the immune system functions in the natural environment. While immune defence may bring increased survival, this may come at a resource cost to other physiological traits, including reproduction. Here, we tested the hypothesis that wild common shrews (Sorex araneus), which produce large numbers of offspring during the one breeding season of their short life span, forgo investment in immunity and immune system maintenance, as increased longevity is unlikely to bring further opportunities for mating. In particular, we predicted that adult shrews, with shorter expected lifespans, would not respond as effectively as young animals to infection. METHODOLOGY/PRINCIPAL FINDINGS: We examined haemolymphatic tissues from wild-caught common shrews using light and transmission electron microscopy, applied in conjunction with immunohistology. We compared composition and function of these tissues in shrews of different ages, and the extent and type of inflammatory reactions observed in response to natural parasitic infections. All ages seemed able to mount systemic, specific immune responses, but adult shrews showed some signs of lymphatic tissue exhaustion: lymphatic follicles in adults (n = 21) were both smaller than those in sub-adults (n = 18; Wald = 11.1, p<0.05) and exhibited greater levels of depletion (Wald = 13.3, p<0.05). CONCLUSIONS/SIGNIFICANCE: Contrary to our expectations, shrews respond effectively to their natural parasites, and show little indication of immunosenescence as adults. The pancreas of Aselli, a unique lymphoid organ, may aid in providing efficient immune responses through the storage of large numbers of plasma cells. This may allow older animals to react effectively to previously encountered parasites, but infection by novel agents, and eventual depletion of plasma cell reserves, could both still be factors in the near-synchronous mortality of adult shrews observed shortly after breeding
Techniques of DNA-studies on prehispanic ectoparasites (Pulex sp., Pulicidae, Siphonaptera) from animal mummies of the Chiribaya Culture, Southern Peru
Mise à jour taxonomique et répartition des puces du genre Ctenophthalmus
Taxonomic update and geographic distribution of fleas of the genus Ctenophthalmus Kolenati 1856 in the Western Palearctic Region (Insecta: Siphonaptera: Ctenophthalmidae). Among fleas (Siphonaptera), the genus Ctenophthalmus is the one that comprises the largest number of taxa and is also characterized by a large geographical range. Here, we present a taxonomic revision of the Western Paleartic subgenera, groups, species and subspecies. We recognized a total of 143 taxa (57 species and 86 subspecies). These taxa are clustered into 23 groups of species, which fall into seven of the 16 subgenera of the genus Ctenophthalmus. According to Hopkins & Rothschild (1966), the subgenus Ctenophthalmus would only include the agyrtes group, itself divided into subgroups. We decided to raise these subgroups to group status to clarify taxonomic relationships within the subgenus Ctenophthalmus. Within this subgenus, the arvernus group is renamed baeticus, the fransmiti group is confirmed, and the egregius group is created. For each taxon, we provided information on geographical distribution, mammalian hosts, and host specificity
Macroparasites of introduced parakeets in Italy: a possible role for parasite-mediated competition
Alien species are considered a cause of biodiversity loss throughout the world. An important but often overlooked
form of competition with native species is the parasite-mediated one. Introduced species may bring their own parasites
from their native ranges (spillover) or get native parasites from native species, thus increasing the parasitesâ spread and
transmission risk (spillback). Thus, a complete knowledge of parasites hosted by introduced species is important to assess
and to possibly prevent impacts. Ring-necked and monk parakeets have been introduced in many European countries,
where they established a number of alien reproductive populations. We sampled 21 ring-necked parakeets and 7 monk
parakeets from Italy and identified 35 arthropod ectoparasites belonging to five species. Amongst those, one species was
native to India (Neopsittaconirmus lybartota), where alien populations of ring-necked parakeet may have been originated,
and one species from South America (Paragoniocotes fulvofasciatus), which is typically found of the monk parakeet
in its native range. The other three species of arthropod parasites were native to Italy and commonly found on native species,
suggesting the possibility of spillback processes