Spotted fever (SF) is a tick-borne disease associated with Rickettsia spp.. In the Pampa biome, Southern Brazil, cases of SF seem to be strongly linked with the practice of hunting wild animals. An investigation of rickettsiae in tick species found on wild animals could provide more information regarding the rickettsiosis enzootic cycle. The aim of this study is to describe the results of a molecular survey of Rickettsia spp. in the Neotropical deer tick, Haemaphysalis juxtakochi Cooley, 1946 (Acari: Ixodidae), from the Brazilian Pampa. Ticks were obtained from 14 road-killed gray brocket deer, Mazama gouazoubira (Artiodactyla: Cervidae), found in nine different municipalities of Rio Grande do Sul state, Southern Brazil. Ticks were processed individually to obtain genomic DNA, and then Rickettsia spp. was investigated using a set of PCR reactions that amplified the rickettsial fragments of the gltA, ompA, and htrA genes. Of the 24 tick samples tested, DNA of Rickettsia parkeri sensu stricto (s.s.) was found in 11 H. juxtakochi specimens collected in two different areas of the Brazilian Pampa. This is the first report of R. parkeri s.s. (the main agent associated with SF in the Uruguayan, Argentinian, and Brazilian Pampa) in H. juxtakochi ticks. These findings indicate that R. parkeri s.s. may be much more common and widely distributed in the Pampa biome than previously assumed. Moreover, H. juxtakochi ticks and gray brocket deer could participate in the potential spillover of R. parkeri s.s. from endemic to non-endemic areas in the South American Pampa.
Louse flies or deer keds, Lipoptena spp., are widespread in Neotropical cervids, but the vector-borne pathogens of louse flies had only been previously reported in the Northern hemisphere. This is the first report of Bartonella spp. in deer louse flies (Lipoptena mazamae) in the neotropics collected from gray brocket deer ( Mazama gouazoubira ) in Southern Brazil. DNA from Bartonella sp. was detected in all 429 L. mazamae collected from 11 road-killed gray brocket deer. The same sequences of DNA of Bartonella spp. were identified in samples. Gray brocket deer are abundant in Brazil, so Bartonella-infected Lipoptena spp. may be widely distributed in the neotropics.
ABSTRACT. Spatial habitat use by Lontra longicaudis (Mustelidae, Carnivora) in an anthropically modified environment in Caí river, Rio Grande do Sul , Brazil. The use of shelters and space by the Neotropical otter, Lontra longicaudis (Olfers, 1818), was studied in an environment formerly and presently altered by human presence in the Caí river, Triunfo, RS. Most marking sites were used occasionally, while a small percentage was frequently and intensely used. Most sprainting was observed on the soil, and sites were, on average, 1.65m away from the water level. In total, seven shelters were found in the study area and the otter showed preference for specific ones. The most used shelter was a holt built in the riverbank under the roots of a tree. This was the largest shelter and the only one presenting underground galleries. The other shelters were above ground, amongst heaps of branches beneath the vegetation, or under roots and/or fallen tree trunks. The use of space by the otter was correlated to the location of the shelters and to the level of vegetation cover, and seems to be poorly influenced by human disturbance. For the Neotropical otter conservancy we indicate the importance of maintaining the riparian buffers and the protection of the areas with the presence of shelters. KEYWORDS.Neotropical otter, scent marking, shelters, sprainting sites. RESUMO.A utilização de abrigos e do espaço pela lontra neotropical (Lontra longicaudis) (Olfers, 1818), foi estudada em um ambiente alterado e com presença humana no rio Caí, Triunfo, RS. A maioria dos sítios de marcação teve uso ocasional, e uma pequena percentagem teve uso frequente e intenso. A maioria das marcações de cheiro se encontrava no solo a uma média de distância de 1,65m da linha d'água. Ao todo foram encontrados sete abrigos na área de estudo, sendo que a lontra demonstrou preferência por abrigos específicos. O abrigo mais utilizado se constituía em escavações na barranca do rio sob as raízes de uma árvore, sendo este o de maiores dimensões e o único com galerias sob o solo. Os demais abrigos se encontravam no nível do solo e consistiam em emaranhados de galhos sob a vegetação, ou de raízes e/ou troncos caídos. O uso do espaço pela lontra esteve correlacionado à localização de suas tocas, ao grau de cobertura vegetal do local e parece ter sido pouco influenciado pelo distúrbio humano. Para medidas de conservação da lontra neotropical ressalta-se a importância da manutenção da mata ciliar e a proteção das áreas com a presença de abrigos. PALAVRAS-CHAVE.Lontra neotropical, marcação de cheiro, abrigos, sítios de marcação.
RESUMO.-[A PCR em tempo real de swab nasal não é adequada para o diagnóstico in vivo de tuberculose bovina.] A tuberculose bovina (bTB) é uma zoonose que causa perdas econômicas e riscos à saúde pública em muitos países. O diagnóstico da doença em animais vivos é realizado pelo teste intradérmico da tuberculina, que é baseado em reações de hipersensibilidade tardia. Como a tuberculose tem resposta imunológica complexa, este teste tem limitações em termos de sensibilidade e especificidade. Este estudo procurou desenvolver uma abordagem alternativa para o diagnóstico in vivo da tuberculose bovina, com base na reação em cadeia da polimerase (PCR) em tempo real. Bovine tuberculosis (bTB) is a zoonosis causing economic losses and public health risks in many countries. The disease diagnosis in live animals is performed by intradermal tuberculin test, which is based on delayed hypersensitivity reactions. As tuberculosis has complex immune response, this test has limitations in sensitivity and specificity. This study sought to test an alternative approach for in vivo diagnosis of bovine tuberculosis, based on real-time polymerase chain reaction (PCR). DNA samples, extracted from nasal swabs of live cows, were used for SYBR ® Green real-time PCR, which is able to differentiate between Mycobacterium tuberculosis and Mycobacterium avium complexes. Statistical analysis was performed to compare the results of tuberculin test, the in vivo gold standard bTB diagnosis method, with realtime PCR, thereby determining the specificity and sensitivity of molecular method. Cervical comparative test (CCT) was performed in 238 animals, of which 193 had suitable DNA from nasal swabs for molecular analysis, as indicated by amplification of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) gene, and were included in the study. In total, 25 (10.5%) of the animals were CCT reactive, of which none was positive in the molecular test. Of the 168 CCT negative animals, four were positive for M. tuberculosis complex at real time PCR from nasal swabs. The comparison of these results generated values of sensitivity and specificity of 0% and 97.6%, respectively; moreover, low coefficients of agreement and correlation (-0.029 and -0.049, respectively) between the results obtained with both tests were also observed. This study showed that real-time PCR from nasal swabs is not suitable for in vivo diagnosis of bovine tuberculosis; thus tuberculin skin test is still the best option for this purpose.
Among the 251 described species of ticks from the genus Ixodes, only eight were previously reported in Brazil, Ixodes amarali, Ixodes aragaoi, Ixodes auritulus, Ixodes fuscipes, Ixodes loricatus, Ixodes luciae, Ixodes paranaensis and Ixodes schulzei. Of those species, I. loricatus is considered commonly found, whereas I. auritulus and I. aragaoi were registered just one time in Rio Grande do Sul (RS) state, Southern Brazil. This paper aims to update the Ixodes species occurring in RS through the investigation of the ixodofauna of small rodents. Data from 314 wild rodents were analyzed from nine municipalities of Pampa biome and five from the Atlantic Rainforest in RS. Rodents belonging to the following species were infested by Ixodes spp. ticks: Akodon azarae, Akodon montensis, Akodon paranaensis, Akodon reigi, Calomys laucha, Delomys dorsalis, Deltamys kempi, Holochilus brasiliensis, Oligoryzomys flavescens, Oligoryzomys nigripes, Oxymycterus nasutus, Scapteromys tumidus (Cricetidae) and Cavia aperea (Caviidae). The tick identification was performed based on morphological dichotomous keys, their updates and by molecular techniques. Considering the ticks from the rodents and those collected directly from the environment, 34 specimens of Ixodes spp. were collected. Our results improved to five the list of Ixodes species that occur in RS: I. loricatus, I. auritulus, I. aragaoi, I. fuscipes and I. longiscutatus. Moreover, the finding of I. longiscutatus increases to nine the number of Ixodes species in Brazil. The occurrence of two species of the Ixodes ricinus complex (I. aragaoi and I. fuscipes) highlights the potential impact of Ixodes spp. ticks on public health.
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