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1.
Exp Appl Acarol ; 92(1): 151-159, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38219227

RESUMEN

This study presents the results of the molecular detection of tick-borne microorganisms in Amblyomma tigrinum Koch collected near the city of Viedma, Río Negro, Argentina. Ticks were collected in their non-parasitic stage, on pet dogs and on Lycalopex gymnocercus (Pampa fox). Also, six tick samples from humans were analyzed. All ticks were morphologically identified to species level and genomic DNA was extracted. The DNA samples were examined by end point PCR assays to amplified DNA of Anaplasma sp., Babesia sp., Ehrlichia sp., Rickettsia sp. and Theileria sp. Although all tested DNA samples from the collected ticks resulted negative to the detection of Piroplasmida and Rickettsia spp., 16 samples (16.5%, including all hosts) were positive in the 16S rDNA gene PCR that detects bacteria from the Anaplasmataceae family. Phylogenetic analysis of seven obtained partial sequences resulted in the identification of three bacteria: two Ehrlichia spp. (related to Ehrlichia sp. strain Iberá and strain Viedma) and Candidatus Anaplasma boleense. The latter finding represents the first detection of this novel Candidatus species in A. tigrinum. Based on the results of this study, it must be assumed that the diversity of bacteria of the Anaplasmataceae family in Argentina is greater than previously thought, and that these bacteria can infect a wide range of domestic and wild animals.


Asunto(s)
Anaplasmataceae , Enfermedades de los Perros , Ixodidae , Rickettsia , Enfermedades por Picaduras de Garrapatas , Garrapatas , Humanos , Animales , Perros , Garrapatas/microbiología , Ixodidae/microbiología , Amblyomma/genética , Argentina , Filogenia , Ehrlichia , Rickettsia/genética , Anaplasma/genética , ADN Bacteriano/análisis , Enfermedades por Picaduras de Garrapatas/veterinaria , Enfermedades de los Perros/parasitología
2.
Pathogens ; 12(11)2023 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-38003808

RESUMEN

This study addresses the variability of the mitochondrial cytochrome oxidase subunit I (COI) and 16S rDNA (16S), and nuclear internal transcriber spacer ITS2 (ITS2) genes in a set of field-collected samples of the cattle tick, Rhipicephalus microplus (Canestrini, 1888), and in geo-referenced sequences obtained from GenBank. Since the tick is currently considered to be a complex of cryptic taxa in several regions of the world, the main aims of the study are (i) to provide evidence of the clades of the tick present in the Neotropics, (ii) to explore if there is an effect of climate traits on the divergence rates of the target genes, and (iii) to check for a relationship between geographical and genetic distance among populations (the closest, the most similar, meaning for slow spread). We included published sequences of Rhipicephalus annulatus (Nearctic, Afrotropical, and Mediterranean) and R. microplus (Afrotropical, Indomalayan) to fully characterize the Neotropical populations (total: 74 16S, 44 COI, and 49 ITS2 sequences included in the analysis). Only the clade A of R. microplus spread in the Nearctic-Neotropics. Both the K and Lambda's statistics, two measures of phylogenetic signal, support low divergence rates of the tested genes in populations of R. microplus in the Neotropics. These tests demonstrate that genetic diversity of the continental populations does not correlate either with the geographic distance among samples or with environmental variables. The low variability of these genes may be due to a combination of factors like (i) the recent introduction of the tick in the Neotropics, (ii) a large, effective, and fast exchange of populations, and (iii) a low effect of climate on the evolution rates of the target genes. These results have implications for the ecological studies and control of cattle tick infestations.

3.
Vet Res Commun ; 47(4): 2241-2245, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37084109

RESUMEN

The aim of this work is to report the first detection of Procyon cancrivorus naturally co-infected with Hepatozoon sp. cf. H. procyonis and a novel Anaplasma strain from South America and potential vector tick species associated. On August 30, 2016, a specimen of P. cancrivorus was found dead on the route in Chaco province, Argentina. A tick and a blood sample by cardiac puncture was collected from the specimen. DNA was extracted from blood sample and the tick was morphological identity as a female of Amblyomma ovale. Molecular detection of Anaplasmataceae family and Hepatozoon spp. agents was performed targeting two different loci: 16 S rRNA and 18 S rRNA gene. The phylogenetic analyses show that the Anaplasma sp. strain detected in P. cancrivorus in this study is similar to Anaplasma sp. strains previously detected in Nasua nasua and A. ovale from Brazil. Furthermore, Hepatozoon sp. of the H. procyonis group was amplified that is phylogenetically closely related to H. procyonis reported in N. nasua from Brazil. Since it was not exactly the same as the latter, it was decided to name at Hepatozoon sp. cf. H. procyonis. It is possible that, this potential new species of Anaplasma would be specific for Procyonidae family and there are two species of Hepatozoon linked to this family in South America. These results added to other published studies suggest that A. ovale could be a potential vector both for the new potential strain of Anaplasma and for the Hepatazoon sp. of the H. procyonis group.


Asunto(s)
Anaplasmataceae , Apicomplexa , Carnívoros , Procyonidae , Garrapatas , Femenino , Animales , Mapaches , Anaplasma/genética , Rickettsiales , Argentina , Filogenia , Brasil
4.
Comp Immunol Microbiol Infect Dis ; 96: 101980, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37079984

RESUMEN

The present study aimed at the molecular detection of Anaplasma spp. in different samples obtained from cattle, goats and free-living Rhipicephalus microplus ticks from Argentina. DNA of members of the Anaplasmataceae family was detected by different PCR assays. The phylogenetic analyses of the obtained partial DNA sequences of the 16 S rDNA gene resulted in the identification of two different Anaplasma spp.: (I) Anaplasma platys-like bacteria (in blood sample from cattle and pools of R. microplus larvae and (II) Candidatus Anaplasma boleense (in blood samples from goats and one pool of R. microplus larvae of R. microplus). Candidatus A. boleense was found in two provinces that belong to different biogeographic regions, which leads to the conclusion that this bacterium may be widely distributed in Argentina. Interestingly, both Anaplasma spp. were found in the same R. microplus population in Chaco province, indicating that these two strains of Anaplasma are circulating in the same tick population. The results of this work represent the first report of the circulation of A. platys-like bacteria and Ca. A. boleense in domestic ruminants and free-living R. microplus ticks in Argentina. Further studies to determine the prevalence of infection, dispersion, clinical impact, transmission routes and cross-reactivity in serological tests of both Anaplasma species are needed.


Asunto(s)
Anaplasmosis , Enfermedades de los Bovinos , Enfermedades de las Cabras , Rhipicephalus , Animales , Bovinos , Filogenia , Argentina/epidemiología , Anaplasma/genética , Rhipicephalus/microbiología , Rumiantes , Cabras/microbiología , Bacterias , Anaplasmosis/epidemiología , Anaplasmosis/microbiología , Enfermedades de los Bovinos/epidemiología , Enfermedades de los Bovinos/microbiología , Enfermedades de las Cabras/epidemiología , Enfermedades de las Cabras/microbiología
5.
Vet Parasitol Reg Stud Reports ; 39: 100850, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36878633

RESUMEN

The aim of this work was to describe the tick community associated to domestic mammals in rural areas from the Yungas lower montane forest of Argentina. The circulation of tick-borne pathogens was also analyzed. Samples of ticks parasitizing cattle, horses, sheep and dogs were carried out in different seasons, and questing ticks were collected from vegetation and analyzed to detect the presence of Rickettsia, Ehrlichia, Borrelia and Babesia by a battery of different PCRs. The structure of the tick communities was analyzed through the Chao1 species richness estimator, the Shannon-Wiener index and the Horn index of community similarity. Eight tick species were collected in the study area: Amblyomma sculptum, Rhipicephalus microplus, Amblyomma hadanii, Dermacentor nitens, Amblyomma ovale, Haemaphysalis juxtakochi, Ixodes pararicinus and Rhipicephalus sanguineus sensu stricto. However, A. sculptum was by far the dominant species in the tick assemblages analyzed, and this was reflected in the low diversity values obtained. Dermacentor nitens, A. sculptum and R. microplus were the three species associated to horses. The predominance of A. sculptum was also observed in the tick samples obtained from dogs, even on two tick species, namely A. ovale and R. sanguineus s.s., which have dogs as the principal domestic host. Rhipicephalus microplus and A. sculptum were the most abundant ticks on cattle, while few specimens of I. pararicinus, A. hadanii and D. nitens were found on bovines. Dermacentor nitens ticks were found to be infected with B. caballi, which indicate the circulation of this pathogen of horses in the Yungas area. The detection of a strain of Borrelia sp. belonging to the B. burgdorferi s.l. complex in I. pararicinus is consistent with previous findings made in Argentina, but the public health relevance of this vector-microorganism association is far from being similar to that occurs in the northern hemisphere because there are practically no records of these tick species parasitizing humans in South America. The tick community of rural areas of the Yungas lower montane forest is composed by species which are potential vectors of pathogenic microorganism with veterinary and public health importance, circulating in a human-wildlife-livestock interface.


Asunto(s)
Borrelia , Ixodes , Rhipicephalus , Humanos , Caballos , Bovinos , Animales , Perros , Ovinos , Argentina/epidemiología , Mamíferos , Amblyomma , Bosques
6.
Ticks Tick Borne Dis ; 14(3): 102135, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36773558

RESUMEN

The aim of this study was to report tick infestations on wild birds from four Phytogeographic Provinces of Argentina. A total of 1085 birds was captured (124 species, 97 genera, 29 families and 13 orders), and ticks were collected from 265 birds (48 species, 40 genera and five orders). A total of 1469 ticks (1102 larvae, 363 nymphs and 4 females) belonging to 15 tick species (Amblyomma calcaratum, Amblyomma dubitatum, Amblyomma nodosum, Amblyomma ovale, Amblyomma parvum, Amblyomma sculptum, Amblyomma tigrinum, Amblyomma triste, Haemaphysalis juxtakochi, Haemaphysalis leporispalustris, Ixodes auritulus sensu lato, Ixodes pararicinus, Ixodes silvanus, Ixodes sp. cf. I. affinis and Ornithodoros sp. cf. O. mimon). Eighty-one new associations between bird species and stages of tick species are detected. The families Thamnophilidae, Turdidae, Thraupidae, Passerellidae, Furnariidae and Troglodytidae were the most prevalent. According to the Phytogeographic Provinces involved in this study, the prevalence of infection for each of them in birds was: (1) Chaco: 28.2% (11 tick species); (2) Yungas: 22.0% (8 tick species); (3) Espinal: 11.1% (2 tick species); and (4) Pampa: 3.9% (1 tick species). This study provided information on the diversity of tick species that parasitize wild birds, the variability of the specific tick-bird associations between the different Phytogeographic Provinces and the relevance of some families of birds as hosts of different tick species.


Asunto(s)
Argasidae , Ixodes , Ixodidae , Passeriformes , Pájaros Cantores , Infestaciones por Garrapatas , Animales , Femenino , Argentina/epidemiología , Animales Salvajes , Infestaciones por Garrapatas/epidemiología , Infestaciones por Garrapatas/veterinaria , Amblyomma
7.
Med Vet Entomol ; 37(2): 407-417, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36734032

RESUMEN

This work aimed to determine if the tick species, Amblyomma sculptum and Amblyomma tonelliae, hybridize along their contact zones in Argentina. Free-living adults and nymphs of A. sculptum and A. tonelliae were collected in seven sampling locations of northern Argentina. In four of them, the two species occur in parapatry (possible hybrid zone) whereas in the other three sites, only one species is known to occur. A total of 65 A. sculptum and 65 A. tonelliae from both, allopatric and parapatric populations, were analysed. The nuclear (ITS2) and mitochondrial (COI and 12SrDNA) gene sequences of each tick were amplified and analysed to verify whether or not they could reveal the presence of hybrids among the parapatric samples. No morphological and molecular evidence was found to support the hypothesis of ongoing natural hybridization. Intrinsic postzygotic barriers may be the cause of lack of gene flow between the two species in areas of co-ocurrence. The results can be explained by the length of time the two lineages spent in allopatry since the middle of the Miocene and before their respective distribution range expanded again reaching a narrow secondary contact zone.


Asunto(s)
Ixodidae , Garrapatas , Animales , Ixodidae/genética , Amblyomma , Argentina , Ninfa , Brasil
8.
Zootaxa ; 5361(1): 53-73, 2023 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-38220777

RESUMEN

Ixodes chacoensis n. sp. is described based on males, females, nymphs and larvae collected from vegetation, ungulates and passerine birds in northeastern Argentina. Ixodes affinis Neumann, 1899 is redescribed based on the original type specimens (females) from Leopardus pardalis, and from recently collected specimens from Costa Rica. Ixodes keiransi n. sp., previously treated as North American populations of Ixodes affinis, is described based on males and females from carnivores and ungulates from the southeastern United States. Concatenated total evidence phylogenetics based on combined DNA sequence analyses from mitochondrial genes (12SrDNA, 16SrDNA and COI) and a nuclear gene (ITS2) corroborate the recognition of these species.


Asunto(s)
Ixodes , Ixodidae , Masculino , Femenino , Animales , Ixodes/genética , Larva/genética , Ninfa/genética
9.
Animals (Basel) ; 12(23)2022 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-36496828

RESUMEN

This study presents the molecular detection of Candidatus Rickettsia andeanae and Ehrlichia sp. in Amblyomma pseudoconcolor Aragão, 1908 (Acari: Ixodidae) collected on a large hairy armadillo (Chaetophractus villosus (Desmarest, 1804)). On 12 October 2020, a specimen of C. villosus was found dead on the road in Río Negro province, Argentina. Molecular detection of Rickettsia and Ehrlichia agents was performed amplifying the gltA and 16S rRNA gene, respectively. One tick, determined morphologically and genetically as A. pseudoconcolor, was collected on C. villosus. The rickettsial agent detected in A. pseudoconcolor was identified as Candidatus Rickettsia andeanae. The Ehrlichia sp. strain showed high sequence similarity to different uncultured Ehrlichia sp. detected in horses, capybaras and Ixodes ornithorhynchi from Nicaragua, Brazil and Australia, respectively. The results of this study and previous findings suggest that A. pseudoconcolor may be a potential vector of some Rickettsia and Ehrlichia bacteria of unknown pathogenicity.

10.
Pathogens ; 11(10)2022 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-36297237

RESUMEN

We aim to provide a harmonized view of the factors that affect the survival and promote the spread of R. microplus in the Neotropics, approaching its different facets of biology, ecology, distribution, and control. We review the interactions among environmental niche, landscape fragmentation, vegetal coverage (abiotic traits), and the biotic aspects of its ecology (abundance of domesticated or wild competent hosts), proposing emerging areas of research. We emphasize a holistic view integrating an economically and ecologically sustainable control of infestations and transmitted pathogens by R. microplus in the Neotropics. Examples of research link the trends of climate, the composition of the community of hosts, the landscape features, and a tailored management based on ecological grounds. Our view is that factors driving the spread of R. microplus are complex and deeply interrelated, something that has been seldom considered in control strategies. The effects of climate may affect the dynamics of wildlife or the landscape composition, promoting new patterns of seasonal activity of the tick, or its spread into currently free areas. In this paper we encourage a One Health approach highlighting the main aspects governing the components of the tick's life cycle and its interactions with livestock and wild animals.

11.
Ticks Tick Borne Dis ; 13(6): 102043, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36150285

RESUMEN

The aim of this study is to determine if there is circulation of microorganisms of the genus Ehrlichia in opossums Didelphis albiventris and their ticks from the Humid Chaco in Argentina. Blood samples of 15 specimens of the opossum D. albiventris were analysed. Immature stages of the ticks Amblyomma ovale (Larvae=26; Nymphs=10), Amblyomma sculptum (Larvae=86; Nymphs=6) and Ornithodoros sp. cf. O. mimon (Larvae=90) were also analyzed. DNA was extracted individually from blood samples and ticks. Molecular detection of Ehrlichia agents was performed targeting two different loci: 16S rRNA and dsb gen. The phylogenetic analyses showed that the Ehrlichia sp. detected in D. albiventris in this study is identical to Ehrlichia sp. strain Natal previously detected in two marsupials from Brazil. Furthermore, a new Ehrlichia strain was amplified from an A. ovale nymph (named as Ehrlichia sp. strain El Bagual) which is phylogenetically closely related to a strain of Ehrlichia sp. detected in Bradypus tridactylus in Brazil. The findings of the current study represent the first report of these two strains of Ehrlichia for Argentina, showing that the diversity of Ehrlichia spp. is greater than previously assumed. Further studies should determine the epidemiological relevance of these findings.

12.
Ticks Tick Borne Dis ; 13(2): 101897, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35026614

RESUMEN

Rhipicephalus secundus is reestablished as a valid tick name within the Rhipicephalus sanguineus group and removed from the synonymy list of Rhipicephalus turanicus. Morphological re-description of both male and female of R. secundus and the analysis of its phylogenetic position based on mitochondrial DNA sequences are presented. The morphological re-description was made with tick specimens collected on goat in Israel. The phylogenetic analyses showed that R. secundus belong to a different clade from those formed by R. turanicus sensu stricto (s.s.) and R sanguineus s.s., and by other taxa from the R. sanguineus group. Rhipicephalus secundus is morphologically related to R. turanicus, but the scutal punctation pattern of both male and female allows the morphological differentiation between R. secundus and R. turanicus, punctations being clearly more numerous and larger in the latter. Both male and female of R. secundus can be differentiated from those of R. sanguineus s.s. by the shape of the spiracular plate. In males, the dorsal prolongation of the spiracular plate is equal to the breadth of the adjacent festoon in R. secundus, while it is narrower than the breadth of the adjacent festoon in R. sanguineus s.s. The dorsal prolongation of the spiracular plate in the female of R. secundus is wider than in the female of R. sanguineus s.s. The genital apertures of the females of R. secundus and R. sanguineus are both U-shaped, but in R. sanguineus s.s. it is broader than in R. secundus. Considering the results obtained in this study, it can be stated that R. secundus is present at least in Israel, Palestinian Territories, Turkey, Albania and southern Italy, but it is necessary to carry out additional studies to determine the geographical range and host usage of this species.


Asunto(s)
Ixodidae , Rhipicephalus sanguineus , Rhipicephalus , Animales , ADN Mitocondrial/genética , Femenino , Ixodidae/genética , Masculino , Filogenia , Rhipicephalus/genética , Rhipicephalus sanguineus/genética
13.
Vet Parasitol Reg Stud Reports ; 24: 100544, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-34024398

RESUMEN

The aim of this study was to report the finding of a nymph attached to an Argentinean tourist returning from South Africa. The nymph specimen was morphologically analysed, submitted to DNA extraction and amplifying the 16S rRNA mitochondrial gene. Additionally, the nymph DNA was screened for Rickettsia, Ehrlichia and Anaplasma infection. The nymph was determined to belong to Amblyomma marmoreum species complex. No specific diagnosis was achieved because the comparative descriptions of species in this complex contain important discordances, and the DNA sequence obtained in the present study is positioned within the same clade with sequences of A. marmoreum see above, but the genetic divergence with them (4.96 and 5.76%) indicate that they belong to different species. No DNA of the Rickettsiales order bacterial was detected in the A. marmoreum species complex nymph.


Asunto(s)
Rickettsia , Garrapatas , Animales , Argentina , ARN Ribosómico 16S/genética , Rickettsia/genética , Sudáfrica , Garrapatas/microbiología
14.
Sci Rep ; 10(1): 9269, 2020 06 09.
Artículo en Inglés | MEDLINE | ID: mdl-32518281

RESUMEN

The relationships between ticks and hosts are relevant to capture the ecological background driving the evolution of these parasites. We used a set of 4,764 records of ticks of the genera Amblyomma, Ixodes, and Haemaphysalis and their hosts in the Neotropics to approach the tick-host relationships using a network-based construct. The network identified 9 clusters of interacting hosts and ticks partially connected by 22 tick species that switch their host range according to their life cycle stage. These links among clusters do not confer an extra resilience to the network following removal of hosts and subsequent cascade extinctions of ticks: the robustness of the network slightly changed when these inter-clusters links are considered. Phylogenetic clustering of ticks to hosts at cluster level was not significant (p > 0.15) but if examined individually 63 tick species/stages (59%) displayed such clustering, suggesting that their hosts have a related phylogenetic background. We interpreted these results under an ecological perspective in which ticks could track its environmental niche associating to vertebrates that would maximize tick survival under the range of abiotic traits. We encourage these integrated analyses to capture the patterns of circulation of tick-transmitted pathogens, a topic still unaddressed in the Neotropical region.


Asunto(s)
Ixodidae/fisiología , Vertebrados/parasitología , Animales , Análisis por Conglomerados , Especificidad del Huésped , Interacciones Huésped-Parásitos , Ixodes/fisiología , Filogenia , Clima Tropical
15.
Exp Appl Acarol ; 81(3): 421-439, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32564254

RESUMEN

In this study, we sequenced two complete mitochondrial genomes of Amblyomma ovale, a tick of public health importance. Sequencing two distinct individuals, the resulting mitochondrial genomes were 14,756 and 14,760 bp in length and maintained the same gene order previously reported in Amblyomma. These were combined with RNA-seq derived mitochondrial sequences from three additional species, Amblyomma aureolatum, Amblyomma maculatum, and Amblyomma moreliae, to carry out mitogenome comparative and evolutionary analyses against all previously published tick mitochondrial genomes. We described a derivative genome rearrangement that isolates Ixodes from the remaining Ixodidae and consists of both a reverse translocation as well as an event of Tandem Duplication Random Loss. Genetic distance analyses indicated that cox2, nd1, nd5, and 16S are good candidates for future population studies in A. ovale. The phylogenetic analyses corroborated the utility of complete mitochondrial genomes as phylogenetic markers within the group. This study further supplements the genome information available for Amblyomma and facilitates future evolutionary and population genetic studies within the genus.


Asunto(s)
Genoma Mitocondrial , Ixodidae , Animales , Secuencia de Bases , Ixodidae/genética , Filogenia
16.
Acta Trop ; 210: 105588, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32553859

RESUMEN

To obtain information about rickettsial bacteria in ticks of the genus Ixodes from Argentina and Uruguay, specimens of I. fuscipes (previously named as I. aragaoi), Ixodes pararicinus, Ixodes sp. cf. I. affinis, and Ixodes sp. were tested targeting the rickettsial gltA and ompA genes. Rickettsial bacteria was detected in all of these species. Rickettsia found in Ixodes sp. is closely related to Ca. Rickettsia mendelii, which was previously detected in I. ricinus of the Czech Republic and later in I. brunneus from the USA. Phylogenetic analyses of the Rickettsia strains found in I. fuscipes, I. pararicinus, and Ixodes sp. cf. I. affinis showed that these strains form a clade together with R. buchneri detected in I. scapularis from the USA, which is closely related to R. monacensis from Europe. Rickettsia buchneri, R. cooleyi and the Rickettsia detected in I. fuscipes, I. pararicinus, and Ixodes sp. cf. I. affinis clustered together in a clade well supported, which suggest that they are different strains of R. buchneri. The phylogenetic analysis shows that Ixodes ticks that are closely related in evolutionary terms (i.e. Ixodes species from the I. ricinus complex, I. brunneus-Ixodes sp.) share closely related rickettsial strains. The results of this study show that rickettsial bacteria are present in Ixodes ticks from Argentina and describe the first detection of Ca. R. mendelii in South America.


Asunto(s)
Ixodes/microbiología , Rickettsia/aislamiento & purificación , Animales , Femenino , Masculino , Filogenia , Rickettsia/clasificación , Rickettsia/genética , América del Sur
17.
Comp Immunol Microbiol Infect Dis ; 69: 101418, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31958747

RESUMEN

The aim of this study was to investigate if there is a phylogenetic divergence of Rickettsia amblyommatis strains from different phytogeographic provinces of Argentina and South America. Therefore, ompA and ompB gene sequences of R. amblyommatis DNA detected in Amblyomma hadanii and Amblyomma neumanni ticks from the Yungas and Chaco phytogeographic provinces, respectively, were obtained. These sequences were compared with GenBank sequences from R. amblyommatis from different countries of the American continent. The analyses shown that ompA haplotypes of R. amblyommatis form two clusters which differ phylogenetically. Regarding to ompB sequences, three groups of R. amblyommatis strains were detected. It could be shown that strains of R. amblyommatis detected in A. hadanii from the phytogeographic province Yungas are phylogenetic different to them detected in A. neumanni from the phytogeographic province Chaco. Furthermore, it could be observed that strains detected in different tick species associated with different phytogeographic provinces of the American continent differ phylogenetically.


Asunto(s)
Filogenia , Infecciones por Rickettsia/epidemiología , Infecciones por Rickettsia/microbiología , Rickettsia/clasificación , Rickettsia/genética , Animales , Argentina/epidemiología , Proteínas de la Membrana Bacteriana Externa/genética , Genes Bacterianos , Haplotipos , Infecciones por Rickettsia/transmisión , Enfermedades por Picaduras de Garrapatas/epidemiología , Enfermedades por Picaduras de Garrapatas/microbiología , Enfermedades por Picaduras de Garrapatas/transmisión , Garrapatas/microbiología
18.
Parasitol Res ; 119(1): 43-54, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31782013

RESUMEN

The goal of this study was to clarify the taxonomic status of the Ixodes ricinus complex in the Southern Cone of America, by using morphological characters and molecular markers (mitochondrial 16SrDNA and cox1 genes). The morphological analysis indicates that three different taxa of the I. ricinus complex occur in this region: Ixodes pararicinus, Ixodes aragaoi, and Ixodes sp. cf. I. affinis. The most prominent diagnostic character among them is the size of scutal punctations in both male and female ticks. In the males of Ixodes sp. cf. I. affinis, the punctations on the central field and along the median marginal groove of the scutum are clearly larger than in the males of I. aragaoi and I. pararicinus, while the punctations of I. aragaoi are larger but less numerous than in I. pararicinus. The punctations in Ixodes sp. cf. I. affinis females are larger and deeper than in females of I. aragaoi and I. pararicinus, and those of I. aragaoi are slightly larger than in I. pararicinus. The length of the lateral posterior denticles of the male hypostome is comparatively longer in I. aragaoi than in the other two species, and longer in Ixodes sp. cf. I. affinis than in I. pararicinus. In the 16S analysis, I. pararicinus and I. aragaoi are monophyletic (99% and 98% bootstrap support, respectively), while Ixodes cf. I. affinis does not represent a single lineage. In the cox1 analysis, both I. pararicinus and I. aragaoi are well-defined taxa, but the bootstrap support for Ixodes sp. cf. I. affinis is low (67%). In general, there are considerable 16SrRNA differences among lineages of Ixodes sp. cf. I. affinis from different geographical areas. These results may be indicative of the existence of different species. The populations morphologically compatible with I. affinis from Argentina, Colombia, Panama, Belize, and USA should be provisionally named as Ixodes sp. cf. I. affinis until an integrative taxonomic work with further evidence redefines whether or not this taxon actually represents a species complex.


Asunto(s)
Ixodes , Animales , Argentina , Colombia , Femenino , Ixodes/anatomía & histología , Ixodes/clasificación , Ixodes/genética , Masculino , Microscopía Electrónica de Rastreo , Panamá , Filogenia , Infestaciones por Garrapatas
19.
Sci Data ; 6(1): 299, 2019 12 03.
Artículo en Inglés | MEDLINE | ID: mdl-31796749

RESUMEN

The datasets of records of the distribution of ticks and their hosts are invaluable tools to understand the phylogenetic patterns of evolution of ticks and the abiotic traits to which they are associated. Such datasets require an exhaustive collection of bibliographical references. In most cases, it is necessary the confirmation of reliable identification of ticks, together with an update of the scientific names of the vertebrate hosts. These data are not easily available, because many records were published in the so-called "grey literature". Herein, we introduced the Dataset of Ticks in South America, a repository that collates data on 4,764 records of ticks (4,124 geo-referenced) with a special reference to an extra 2,370 records of ticks on cattle, together with a set of abiotic traits, curated from satellite-derived information over the complete target region. The dataset includes details of the phylogenetic relationships of the species of hosts, providing researchers with both biotic and abiotic traits that drive the distribution and evolution of ticks in South America.


Asunto(s)
Bovinos/parasitología , Filogenia , Garrapatas/clasificación , Animales , América del Sur
20.
Vaccines (Basel) ; 8(1)2019 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-31905826

RESUMEN

Ticks and transmitted pathogens constitute a major burden for cattle industry in the Neotropics. To address this limitation, the Spanish Ibero-American Program of Science and Technology in Development office (CYTED) supported from 2018 a network of scientists named "LaGar" (CYTED code 118RT0542) aimed at optimizing the control strategies of cattle ticks in the neotropical region. As part of network activities, a meeting and course were organized on 4-8 November 2019 in Querétaro, Mexico to address the objective of developing the infrastructure necessary for an effective, sustainable (i.e., combination of efficacious acaricides with anti-tick vaccines) and rational (i.e., considering tick ecology, seasonal dynamics and cattle-wildlife interactions) control of cattle tick infestations and transmitted pathogens. The course was focused on scientists, students, cattle holders and producers and pharmaceutical/industry representatives. In this way the course addressed the different views presented by participants with the conclusion of producing a research-driven combination of different interventions for the control of tick tick-borne diseases.

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