Publications by authors named "Jose Manuel Venzal"

In this study, we report soft ticks from bat-inhabiting caves in different areas of Brazil. From 2010 to 2019, we collected 807 tick specimens from nine caves located in four Brazilian states among two biomes. Ticks were morphologically identified as Antricola guglielmonei (282 specimens), Ornithodoros cavernicolous (260 specimens), and Ornithodoros fonsecai (265 specimens).

View Article and Find Full Text PDF
Article Synopsis
  • Chronic lymphocytic leukemia (CLL) is the most prevalent leukemia in dogs, involving the growth of mature but non-functional lymphocytes, often in cytotoxic T cells (TCD8), which may predict better outcomes despite some debate on their prognostic significance.
  • A 10-year-old mixed-breed dog showed signs of CLL, including high lymphocyte counts, anemia, and spleen enlargement; diagnosis was confirmed via blood tests and a myelogram, leading to a chemotherapy regimen that has resulted in a good response with 13 months of survival.
  • The diagnosis was validated through immunophenotyping, myelography, and flow cytometry, which identified the specific T-cell markers and excluded others, confirming the type of CLL
View Article and Find Full Text PDF

Human ehrlichiosis are scantily documented in Uruguay. The aim of this study was to investigate the presence of spp. in and in a gray brocket deer () from Uruguay.

View Article and Find Full Text PDF

In South America, apicomplexan parasites of the genus Hepatozoon have been sporadically detected in mammals. Previous studies in wild canids from Brazil and Argentina demonstrated infections by species genetically related to Hepatozoon americanum. The aim of the present work was to detect the presence of Hepatozoon in road-killed foxes encountered in Uruguayan highways.

View Article and Find Full Text PDF

sensu lato (s.l.), the causative agent of Lyme borreliosis, is the most prevalent tick-borne pathogen in Europe, where it is mainly transmitted by .

View Article and Find Full Text PDF

Ticks are the major arthropod vectors of animal and human pathogens in Europe; thus, information of tick species and their phenology allows identifying those areas and periods involving a high risk of exposure to particular tick-borne pathogens. In order to assess the diversity of exophilic tick species in north-western Spain, questing ticks were collected by flagging in 17 different locations; ticks were microscopically and molecularly identified at the 16S rDNA loci. In addition, phenology of questing ticks in the same region was studied in representative sampling areas of three different ecological regions, where ticks were monthly collected in 300-m transects during two complete years.

View Article and Find Full Text PDF

Associations with environmental and host parameters were assessed to describe tick parasitism patterns in two medium-sized mammals of the Atlantic rainforest region of Argentina. Ticks found on 93 specimens of Nasua nasua and 26 specimens of Didelphis aurita captured at six sites in the Iguazú National Park were collected. Generalized linear models were constructed to explain the presence and abundance of ticks and the most appropriate ones were selected after stepwise simplification.

View Article and Find Full Text PDF

Background: Ixodes ricinus, the predominant tick species in Europe, can transmit the causative agents of important human diseases such as Lyme borreliosis (LB), caused by Borrelia spirochetes. In northern Spain, LB is considered endemic; recently, a significant increase of the annual incidence of LB was reported in the northwestern (NW) region.

Methods: In order to provide information on the prevalence of Borrelia spp.

View Article and Find Full Text PDF

Borrelia burgdorferi sensu lato (s.l.) complex includes the agents of Lyme disease/borreliosis in North America, Europe, and Asia, such Borrelia burgdorferi sensu stricto, Borrelia afzelii, Borrelia garinii, Borrelia bavariensis, Borrelia spielmanii, Borrelia bissettiae, and Borrelia mayonii.

View Article and Find Full Text PDF

Anaplasmataceae family members include vector-borne bacteria of veterinary importance that may also affect humans. Ehrlichia canis and Anaplasma platys are the main members of this family detected in dogs worldwide. In Uruguay there are not many published studies on tick-borne pathogens affecting dogs, the only haemoparasite molecularly confirmed in dogs, is the piroplasm Rangelia vitalii.

View Article and Find Full Text PDF

The piroplasm Rangelia vitalii is the etiological agent of canine rangeliosis, a severe disease affecting domestic dogs in South America. Two domestic dogs from two different Departments (Salto and Treinta y Tres) of Uruguay presented with clinical signs such as apathy, anorexia, pale mucous membranes, jaundice, and hemorrhagic manifestations, suggestive of a canine vector-borne disease. Molecular analysis, based on PCR and DNA sequencing of portions of the 18S rRNA gene, revealed that both dogs were infected by R.

View Article and Find Full Text PDF

Brazil harbors five species of Cypseloidinae swifts. Those from Streptoprocne and Cypseloides genera have a very distinct ecology. They shelter at night and build nests in moist cliffs by waterfalls.

View Article and Find Full Text PDF

Many argasid tick species are known only through their larval descriptions, in which the chaetotaxy, together with other external morphological characteristics, has been used to separate genera and species. However, the illustrations of these features are based on optical microscopy alone and many of these features are not clearly defined. Because of the difficulties in determining the larval and nymph stages of some genera, we have prepared illustrated keys for the immature stages of argasids, including an up-to-date list of the known species of the Neotropical region.

View Article and Find Full Text PDF

The argasid tick Ornithodoros marinkellei Kohls, Clifford, and Jones, 1969 was described 4 decades ago based on larval specimens collected from bats (Pteronotus spp.) in Colombia and Panama. Thereafter, larval O.

View Article and Find Full Text PDF

Carios mimon is an argasid tick common on Chiroptera, originally described from larvae collected on bats Mimon crenulatum from Bolivia and Eptesicus brasiliensis from Uruguay. Later it was also registered from Argentina and recently included among the Brazilian tick fauna. In Brazil, this species is very aggressive to man, resulting in intense inflammatory response and pain.

View Article and Find Full Text PDF

This article reports on the detection of Rickettsia felis in Argentina in Ctenocephalides felis fleas collected from a dog and analyzed by polymerase chain reaction (PCR) amplification and DNA sequencing.

View Article and Find Full Text PDF

Amblyomma triste is the most prevalent tick species reported in human tick bites in Uruguay and has been found to be infected with Rickettsia parkeri, but no other microorganisms have been reported from this tick. A sample of 254 adults of A. triste was collected by flagging on vegetation in suburban areas in southern Uruguay.

View Article and Find Full Text PDF

The immature stages of the Neotropical tick Ixodes (Ixodes) pararicinus Keirans & Clifford, 1985 are described from specimens in a laboratory colony initiated from engorged females collected on cattle and larvae fed on mice and chickens. The larva and nymph of I. pararicinus are described using SEM micrographs as well as drawings for some features of the larva.

View Article and Find Full Text PDF

Three new species of Antricola (Acari: Argasidae) are described from adult specimens collected on bat guano in different caves in Brazil. The female of Antricola guglielmonei n. sp.

View Article and Find Full Text PDF