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1.
Exp Appl Acarol ; 92(3): 555-565, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38468022

RESUMO

The main way to avoid contact with ticks and consequently tick-borne disease is the use of synthetic repellents. The search of new repellent compounds to increase the possibilities of use in strategies controls are necessary. The present study evaluated the repellent activity of two natural terpenes carvacrol and thymol in each one two different formulation (encapsulated and nonencapsulated with yeast cell wall) against the ticks Amblyomma sculptum and Rhipicephalus sanguineus sensu lato nymphs. Nymphs of A. sculptum and R. sanguineus s.l. of a single generation were used. The vertical filter paper repellency assay were performed with different concentration of both terpenes encapsulated and nonencapsulated in yeast cell wall. The repellent concentration 50% (RC50) were calculated to each compound formulation. Both carvacrol and thymol (encapsulated and nonencapsulated), had a repellent activity against A. sculptum and R. sanguineus s.l nymphs. Amblyomma sculptum was more sensitive to nonencapsulated carvacrol (RC50 values: 0.0032 to 0.0082 mg/cm2 after 1 and 15 min) (P < 0.05), while R. sanguineus s.l. was more sensitive to encapsulated carvacrol (RC50 values: 0.00008 to 0.0035 mg/cm2 after 1 and 15 min) (P < 0.05). Among tick species, R. sanguineus s.l. was more sensitive for most compounds than A. sculptum (P < 0.05). Although with distinct repellent activities, carvacrol and thymol encapsulated can be a promising alternative to synthetic repellents against A. sculptum and R. sanguineus s.l.


Assuntos
Amblyomma , Cimenos , Ninfa , Rhipicephalus sanguineus , Timol , Cimenos/farmacologia , Animais , Timol/farmacologia , Ninfa/efeitos dos fármacos , Ninfa/crescimento & desenvolvimento , Rhipicephalus sanguineus/efeitos dos fármacos , Parede Celular/efeitos dos fármacos , Acaricidas/farmacologia , Monoterpenos/farmacologia , Repelentes de Insetos/farmacologia , Saccharomyces cerevisiae/efeitos dos fármacos
2.
Exp Appl Acarol ; 75(3): 309-318, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29846852

RESUMO

This study evaluated rickettsial infection in ticks collected on toads from the northern Brazilian Amazon (Amapá state), where to our knowledge there are neither records of ticks from amphibians nor rickettsial infections in ticks. During 2016-2017, a total of 22 free-living toads were captured and identified as Rhinella marina. Overall, 12 (54.5%) toads were parasitized by a total of 97 ticks (6 males, 39 females, 31 nymphs, 21 larvae), giving a mean intensity of 8.1 ticks per infested toad. Two tick species were morphologically identified: Amblyomma rotundatum Koch (31 females, 14 nymphs), and Amblyomma dissimile Koch (6 males, 8 females, 17 nymphs). The 21 larvae were morphologically denoted as Amblyomma sp. Five toads were co-infested by A. rotundatum and A. dissimile. Morphological identifications were confirmed by nucleotide sequencing of fragments of the mitochondrial genes 16S rDNA, 12S rDNA and/or COX1. A total of 54 ticks were analyzed for the presence of rickettsial DNA. Eleven (9 females and 2 nymphs) out of 14 A. rotundatum ticks contained Rickettsia bellii. None of the 25 specimens of A. dissimile (6 males, 6 females, 13 nymphs) contained amplifiable rickettsial DNA. From 15 Amblyomma sp. larvae, a pool of 10 individuals contained Rickettsia sp. strain Colombianensi. Sequencing of the 16S rDNA amplicon derived from the positive pool yielded a sequence of A. dissimile. We detected Rickettsia sp. strain Colombianensi for the first time in Brazil. Prior records of this agent were restricted to Colombia and Honduras. In addition, we report the presence of A. rotundatum for the first time in the state of Amapá, where the only other record of A. dissimile was registered over 20 years ago.


Assuntos
Bufo marinus/parasitologia , Rickettsia/isolamento & purificação , Carrapatos/microbiologia , Animais , Brasil , Feminino , Masculino , Rickettsia/genética
3.
Syst Parasitol ; 94(1): 151-157, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-28062994

RESUMO

A new species of coccidian, Isospora guaxi n. sp., and Isospora bellicosa Upton, Stamper & Whitaker, 1995 (Protozoa: Apicomplexa: Eimeriidae) are recorded from red-rumped caciques Cacicus haemorrhous (L.) in the Parque Nacional do Itatiaia, Brazil. Isospora guaxi n. sp. has sub-spheroidal oöcysts, measuring on average 30.9 × 29.0 µm, with smooth, bi-layered wall c.1.9 µm thick. Micropyle and oöcyst residuum are absent, but a polar granule is present. Sporocysts are ellipsoidal, measuring on average 19.3 × 13.8 µm. Stieda body is knob-like and sub-Stieda body is prominent and compartmentalized. Sporocyst residuum is composed of scattered granules. Sporozoites are vermiform, with one refractile body and a nucleus. Isospora bellicosa has sub-spheroidal to ovoidal oöcysts, measuring on average 27.1 × 25.0 µm, with smooth, bi-layered wall c.1.5 µm thick. Micropyle and oöcyst residuum are absent, but one or two polar granules are present. Sporocysts are ellipsoidal, measuring on average 18.1 × 10.9 µm. Stieda body is knob-like and sub-Stieda body is rounded to rectangular. Sporocyst residuum is composed of a cluster of compact or diffuse granules. Sporozoites are vermiform, with one refractile body and a nucleus. Isospora bellicosa was originally described from the Peruvian meadowlark Sturnella bellicosa deFilippi, a trans-Andean icterid which is allopatric with the cis-Andean C. haemorrhous. Therefore, in conclusion, this current study reveals the dispersion of coccidia from Icteridae across the Andes Mountains, besides describing the sixth isosporoid coccidium infecting an icterid bird.


Assuntos
Coccídios/fisiologia , Isospora/classificação , Isospora/fisiologia , Passeriformes/parasitologia , Animais , Brasil , Demografia , Isospora/citologia , Oocistos/citologia , Especificidade da Espécie , Esporozoítos/citologia
4.
Parasitol Res ; 115(2): 745-9, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26508009

RESUMO

A new coccidian species (Protozoa: Apicomplexa: Isospora) parasitizing the white-shouldered fire-eye Pyriglena leucoptera (Vieillot, 1818) is described in the Parque Nacional do Itatiaia. This park is a protected area in southeastern Brazil with a high degree of vulnerability, representing a "conservation island" of biodiversity. Isospora parnaitatiaiensis n. sp. has oocysts that are ellipsoidal, 23.8 × 19.4 µm, with smooth, bilayered wall, ~1.1 µm thick. Micropyle and oocyst residuum are absent, but one or two polar granules are present. Sporocysts are ellipsoidal, 14.6 × 9.3 µm. The Stieda body is nipple- to knob-like and sub-Stieda body rounded to rectangular. Sporocyst residuum is present, usually as a cluster of numerous granules. Sporozoites are vermiform with two refractile bodies and a nucleus. This is the second isosporoid coccidian described from antbirds (Thamnophilidae).


Assuntos
Doenças das Aves/parasitologia , Coccidiose/veterinária , Isospora/isolamento & purificação , Passeriformes/parasitologia , Animais , Brasil , Núcleo Celular/ultraestrutura , Coccidiose/parasitologia , Fezes/parasitologia , Isospora/classificação , Isospora/citologia , Oocistos/citologia , Esporozoítos/citologia
5.
Zootaxa ; 3760: 96-100, 2014 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-24870075

RESUMO

In the current study, a new coccidian species (Protozoa: Apicomplexa: Eimeriidae), collected from the rufous-browed peppershrike Cyclarhis gujanensis Gmelin, 1789, is reported from Brazil. Isospora pitiguari n. sp. has oocysts, which are spherical to sub-spherical, 26.8 × 25.7 µm, with smooth, bilayered wall ~1.5 µm thick. Micropyle, oocyst residuum, and polar granule are absent. Sporocysts are rounded to slightly ovoidal, 14.4 × 11.6 µm. Stieda body flattened and substieda body prominent and rounded. Sporocyst residuum is composed of granules of different sizes. Sporozoites are vermiform with one refractile body and a nucleus. This is the first description of an isosporoid coccidium infecting a New World vireo.


Assuntos
Eimeriidae/classificação , Eimeriidae/isolamento & purificação , Passeriformes/parasitologia , Animais , Masculino , Oocistos/citologia , Especificidade da Espécie
6.
Ticks Tick Borne Dis ; 15(2): 102294, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38086247

RESUMO

This work aimed to report ticks infesting the wildlife among 15 municipalities of the state of Espírito Santo between 2016 and 2021, within the Atlantic Forest biome of southeastern Brazil. A total of 576 tick specimens (187 males, 56 females, 149 nymphs, and 184 larvae) was collected from 41 species of wild vertebrates (two reptiles, nine mammals, and 30 birds). Ticks were identified by morphological or molecular methods into 18 species, being 12, four, one and one of the genera Amblyomma, Ixodes, Rhipicephalus and Ornithodoros, respectively. Amblyomma rotundatum was the only species collected from reptiles. Ticks collected from mammals were identified as Amblyomma brasiliense, Amblyomma calcaratum, Amblyomma dubitatum, Amblyomma longirostre, Amblyomma nodosum, Amblyomma pacae, Amblyomma sculptum, Amblyomma varium and Rhipicephalus microplus. Amblyomma sculptum was the species found on the widest variety of hosts, collected from four mammal orders and five bird orders. Passeriformes birds were infested by Amblyomma fuscum, A. longirostre (also found on non- passerine birds), A. nodosum, Amblyomma parkeri, Amblyomma romarioi, A. varium and Ixodes loricatus. An adult female of Ixodes rio was collected from a Piciformes bird. Seabirds of the order Procellariiformes were infested by Ixodes percavatus sensu lato and Ixodes uriae. The argasid Ornithodoros capensis was collected from an offshore metallic platform that was used by Suliformes seabirds. Rickettsial agents of the spotted fever group, Rickettsia amblyommatis and Rickettsia sp. strain Pampulha, were detected in the ticks A. longirostre [from the Paraguayan hairy dwarf porcupine (Coendou spinosus)] and A. dubitatum [from the capybara (Hydrochoerus hydrochaeris)], respectively. The following nine tick species are reported for the first time in Espírito Santo state: A. calcaratum, A. fuscum, A. pacae, A. parkeri, A. romarioi, I. loricatus, I. rio, I. uriae, and O. capensis. Although it is also the first report of I. uriae in Brazil, we do not consider it established in the country. Multiple new tick-host associations are reported in the present study.


Assuntos
Ixodes , Ixodidae , Ornithodoros , Rhipicephalus , Infecções por Rickettsia , Rickettsia , Doenças dos Roedores , Infestações por Carrapato , Masculino , Animais , Feminino , Animais Selvagens , Brasil/epidemiologia , Ixodidae/microbiologia , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/veterinária , Infecções por Rickettsia/microbiologia , Mamíferos , Amblyomma , Roedores
7.
Rev Bras Parasitol Vet ; 33(3): e008224, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39383386

RESUMO

Wild animals and domestic dogs living in human dwellings near forested areas can share ectoparasites, including ticks. In this study, we surveyed ticks associated with dogs which tutors living in the Palmares Environmental Protection Area (EPA Palmares). Dogs were classified into three categories, domiciled, semi-domiciled and wandering dogs according to dog care/ type of dwelling. Ticks were collected monthly from January to December, 2020. Overall, 60 (33.9%) out of 177 examined dogs were infested by ticks. Six species of ticks were identified: Rhipicephalus linnaei, Amblyomma aureolatum, Amblyomma sculptum, Amblyomma ovale, Amblyomma dubitatum and Rhipicephalus microplus. The overall prevalence and presence in semi-domicilied+wandering dogs was higher for A. aureolatum than for R. linnaei by the Chi-square statistic tests. A random sample of 50 ticks, collected from 22 different dogs, were processed through molecular analyses. Ticks were submitted to DNA extraction and also by PCR, using specific primers in order to pathogens monitoring. Four males of A. aureolatum yielded DNA sequences (350 bp) that were 100% identical to the type strain of Rickettsia bellii in GenBank (CP000087).


Assuntos
Doenças do Cão , Rhipicephalus , Infestações por Carrapato , Animais , Cães , Brasil , Doenças do Cão/parasitologia , Doenças do Cão/epidemiologia , Infestações por Carrapato/veterinária , Infestações por Carrapato/epidemiologia , Feminino , Ixodidae , Masculino , Prevalência , Doenças Transmitidas por Carrapatos/veterinária , Doenças Transmitidas por Carrapatos/epidemiologia , Rickettsia/isolamento & purificação , Rickettsia/genética
8.
Ticks Tick Borne Dis ; 15(6): 102377, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39013352

RESUMO

Ticks parasitize a wide variety of wild animals, including amphibians and reptiles. In addition to the possibility of microorganism transmission to these hosts, ticks can also cause severe bleeding, and high parasitism can lead to death. Therefore, knowing the diversity of ticks parasitizing amphibians and reptiles is important for conservation and preservation measures for these vertebrates. In the present study, we report parasitism by ticks in amphibians and reptiles from different Brazilian biomes (Amazon, Caatinga, Cerrado and Atlantic Forest). Ticks were collected from amphibians and reptiles deposited from the Herpetological Collection of the Federal University of Maranhão (UFMA), São Luís (Maranhão State), the State University Santa Cruz (UESC), Ilhéus (Bahia State), and the Federal University of São Francisco Valley (Univasf), Petrolina (Pernambuco State). Additionally, ticks were collected from amphibians and reptiles captured and road-killed in the Amazon biome, at Maranhão and Amapá States. Specimens of ticks were photographed under a Zeiss stereomicroscope (5.1 zoom). Map with the locations were made using the Qgis program. Overall, 1973 specimens of amphibians and reptiles were examined. A total of 927 ticks were collected: 98 larvae, 421 nymphs and 408 adults. Six species of ticks were identified: Amblyomma rotundatum and Amblyomma dissimile the most frequent, and Amblyomma cajennense sensu stricto, Amblyomma sculptum, Amblyomma nodosum and Amblyomma humerale, occasionally. Surprisingly, a total of twelve males of A. rotundatum were collected. Here we report new records of association between cold-blooded animals and ticks and reinforce the absence of A. dissimile in the Caatinga, Cerrado and Atlantic Forest biomes. Additionally, we report new records of A. rotundatum males on reptiles in the Amazon biome. This last record allows us to speculate about a possible association of A. rotundatum males with reptiles and the Amazon biome.

9.
Exp Appl Acarol ; 60(1): 55-62, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23100108

RESUMO

The life cycle and behavior of Amblyomma rotundatum were evaluated under laboratory conditions. The experiment started with four engorged females collected from toads (Rhinella schneideri) naturally infested at the Pirapitinga Ecological Station in the state of Minas Gerais, Brazil. Developmental periods of free-living stages were assessed in an incubator at 27 ± 1 °C, >80 % RH and darkness. The complete life cycle, including pre-attachment periods for each parasitic stage, ranged from 126 to 228 days. The pre-attachment, feeding and molting periods increased as the life cycle progressed from larva to adult female. Oviposition lasted about 20 days, with the peak occurring on days 4 and 5. Longevity of nymphs and adult females was quite similar (approximately 250 and 240 days, respectively) and slightly longer than that of larvae. Lesions caused by tick feeding are discussed and a list of known hosts, including new host records for A. rotundatum, is offered.


Assuntos
Bufonidae/parasitologia , Ixodidae/fisiologia , Estágios do Ciclo de Vida , Animais , Comportamento Animal , Brasil , Feminino , Interações Hospedeiro-Parasita , Ixodidae/crescimento & desenvolvimento , Longevidade , Oviposição
10.
Zootaxa ; 3710: 179-91, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-26106682

RESUMO

Ornithodoros mimon is an argasid tick common on Chiroptera in the Neotropical region, where it also bites humans aggressively. Here we describe for the first time all nymphal instars (N1, N2 and N3) of O. mimon based on optical and scanning electron microscopy. Although the nymphal instars of O. mimon resemble each other closely, there are characters that differentiate them: the N3 are taller that N1 and N2; the genital primordium occurs in some N2 and all N3; the spiracular plate in N1 and N2 is cone-like, but in N3 it is semicircular; and the submarginal dorsal groove is less distinct in N1 but more evident in N3. Nymphs of 0. mimon closely resemble the bat-associated species of the genus Ornithodoros included in the Alectorobius group. We review prior descriptions of nymphs of the Alectorobius group and make comparisons with nymphs of O. minon, highlighting characters with diagnostic information, such as the idiosomal shape, presence of discs and hood and absence subapical protuberance of tarsus I. The description of nymphal instars of O. mimon herein presented, improves the taxonomy of the family Argasidae, performing a work more detailed about the immature stage of this species.


Assuntos
Argasidae/ultraestrutura , Animais , Argasidae/classificação , Microscopia Eletrônica de Varredura , Ninfa/classificação , Ninfa/ultraestrutura
11.
Parasit Vectors ; 16(1): 391, 2023 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-37891604

RESUMO

BACKGROUND: The tick Amblyomma cajennense sensu stricto (A. cajennense s.s.) frequently parasitizes animals and humans in the Amazon biome, in addition to being a vector of Rickettsia amblyommatis. In the present study, we evaluated both the population dynamics of A. cajennense s.s. in a degraded area of the Amazon biome and the presence of rickettsial organisms in this tick population. METHODS: The study was carried out in a rural area of the Santa Inês municipality (altitude: 24 m a.s.l.), Maranhão state, Brazil. Ticks were collected from the environment for 24 consecutive months, from June 2021 to May 2023. The region is characterized by two warm seasons: a rainy season (November-May) and a dry season (June-October). We characterized the temporal activity of A. cajennense s.s. on the vegetation by examining questing activity for each life stage (larvae, nymphs, adults [males and females]) in relation to the dry and rainy season. Ticks collected in this study were randomly selected and individually tested by a TaqMan real-time PCR assay that targeted a 147-bp fragment of the rickettsial gltA gene. RESULTS: Overall, 1843 (62.4%) adults (52.6% females, 47.4% males), 1110 (37.6%) nymphs and 398 larval clusters were collected. All adult females and nymphs were morphologically identified as A. cajennense s.s. Larval activity was observed from April to December, with a peak from June to September (dry season); nymph abundance peaked from September to November (transition period between dry and rainy seasons); and adult ticks were abundant from October to May (spring/summer/early autumn). The infection rate by R. amblyommatis in A. cajennense s.s. ticks was at least 7% (7/99). CONCLUSION: Our data suggest a 1-year generation pattern for A. cajennense s.s., with a well-defined seasonality of larvae, nymphs and adults in the Amazon biome. Larvae predominate during the dry season, nymphs are most abundant in the dry-rainy season transition and adults are most abundant in the rainy season. The presence of R. amblyommatis in adult ticks suggests that animals and humans in the study region are at risk of infection by this species belonging to the spotted fever group of Rickettsia.


Assuntos
Ixodidae , Infecções por Rickettsia , Rickettsia , Carrapatos , Animais , Humanos , Masculino , Feminino , Estações do Ano , Amblyomma , Rickettsia/genética , Infecções por Rickettsia/epidemiologia , Infecções por Rickettsia/microbiologia , Carrapatos/microbiologia , Brasil/epidemiologia , Ninfa/microbiologia , Larva/microbiologia , Ecossistema
12.
Exp Appl Acarol ; 58(1): 89-99, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22729500

RESUMO

In the present study the tick prevalence, mean intensity of infestation and species were recorded on birds captured between January 2009 and December 2010 in the Ecological Station Pirapitinga-ESEC from Minas Gerais State, Brazil. A total of 967 birds, from 15 families and 40 species were captured and 165 (17.1 %) individuals were parasitized by ticks. Of these 160 (97 %) belonged to the order Passeriformes. Five tick species were identified: Amblyomma longirostre (n = 274) was the most common species followed by Amblyomma parvum (n = 43), Amblyomma nodosum (n = 39), Amblyomma ovale (n = 24) and Riphicephalus sanguineus (n = 7). None of 61 unengorged larvae molted to nymph. The mean intensity of infestation was 2.7 ± 2.4 ticks per bird (448 ticks/165 birds) ranging from 1 to 10. Only 19 (11.4 %) birds were infested with one species of tick. The remaining birds were infested by two, three or four species of ticks. Also new hosts for all five ticks were recorded. Only nymphs were recorded throughout the year with two similar peaks during autumn and winter 2009 and 2010.


Assuntos
Doenças das Aves/parasitologia , Infestações por Carrapato/veterinária , Carrapatos/classificação , Animais , Doenças das Aves/epidemiologia , Aves , Brasil/epidemiologia , Feminino , Masculino , Prevalência , Estações do Ano , Especificidade da Espécie , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/parasitologia
13.
Exp Appl Acarol ; 58(1): 69-80, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22570058

RESUMO

Ornithodoros mimon Kohls et al. is an argasid tick, originally described from larvae collected on bats from Bolivia and Uruguay. In Brazil the species is aggressive to humans and animals. Nymphs and adults of O. mimon were collected from the roof of a residence in Araraquara, São Paulo, Brazil, whose residents were bitten by ticks. Once in the laboratory, they were fed on rabbits and maintained in biological oxygen demand incubator at 27 ± 1 °C and 90 ± 10 % relative humidity. The females, after mating, laid eggs that resulted in larvae that were identified by the original description and also by the paratypes examination (RML 50271-50274) deposited at the United State National Tick Collection, Georgia, GA, USA. The life cycle of this species was obtained through the acquisition of two generations of ticks (F1 and F2) in the laboratory using rodents and rabbits as hosts. The biological parameters of larva, nymph and adult stages of both generations were recorded from infestations of the laboratory hosts. Larvae showed a profile of feeding for days on the host, whereas the nymphs and adults fed only for few minutes. First nymphal instar (N1) molted to second nymphal instar (N2) without blood meal. The species life cycle was elucidated for the first time.


Assuntos
Ornithodoros/fisiologia , Animais , Feminino , Gerbillinae , Larva/fisiologia , Masculino , Ninfa , Óvulo/fisiologia , Coelhos , Infestações por Carrapato/parasitologia
14.
Ticks Tick Borne Dis ; 12(3): 101680, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33545505

RESUMO

The pivotal role of amphibians in food webs and their value as indicators of disequilibrium in ecosystem health have long been recognized by wildlife biologists. However, massive pathogen-induced declines in global amphibian populations reported during the last 30 years served to alert the scientific community that knowledge of amphibian disease ecology, including parasitic and vector-borne conditions, was and remains incipient. Herein, we report the detection of a Rickettsia bacterium infecting larvae of the argasid tick Ornithodoros faccinii, collected from the toad Rhinella ornata, in Southeastern Brazil. Fragments of the genes 16S rDNA, gltA, htrA, sca1, sca4, and ompB were amplified by polymerase chain reaction (PCR), but the sequence encoding the ompA antigen was not detected. Nucleotide sequencing and multi-locus (gltA, htrA, sca1, and sca4) phylogenetic analyses characterized the bacterium, designated Rickettsia sp. strain Itinguçú, as a novel member of the spotted fever group (SFG) of the Rickettsia, closely related to the Rickettsia massiliae and to a lesser extent the Rickettsia helvetica subgroups. The apparent absence of the ompA protein together with limited levels of nucleotide (90.5 %) and amino acid (82-83 %) sequence identity, relative to the ompB gene of other species in the R. massiliae subgroup, were unusual features that may reflect adaptation to selective pressures exerted by the tick and/or amphibian immune systems. The ompB sequence was exploited to develop a low-cost method for differential identification of Rickettsia sp. strain Itinguçú, based on restriction fragment length polymorphism analysis of amplicons (PCR-RFLP). The characterization of this novel bacterium provided an unprecedented record of infection by an SFG Rickettsia in a member of the family Argasidae infesting a cold-blooded animal and raised the number of tick-associated Rickettsia reported in Brazil to sixteen. Moreover, it highlighted the value of and the requirement for continued and extended surveillance of wildlife as potential sources of emerging tick-borne pathogens.


Assuntos
Bufonidae/parasitologia , Ornithodoros/microbiologia , Rickettsia/isolamento & purificação , Animais , Brasil , Larva/crescimento & desenvolvimento , Larva/microbiologia , Ornithodoros/crescimento & desenvolvimento , Filogenia , Rickettsia/classificação
15.
Rev Bras Parasitol Vet ; 30(2): e027420, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34076155

RESUMO

This study aimed to evaluate the occurrence of endoparasites in fecal samples of capybaras from anthropized areas in seven cities in the state of São Paulo, southeastern Brazil, and natural areas in two locations in the Pantanal biome. For the parasitological evaluation of samples, feces were subjected to centrifugal sedimentation in water-ether and centrifugal flotation in sucrose solution. Out of the 113 samples examined, 97.3% (110/113) were positive for the presence of helminth eggs and/or protozoan oocysts, with 96.7% (89/92) and 100% (21/21) in capybaras from anthropized and natural areas, respectively. Helminth eggs belonging to the Class Cestoda (Monoecocestus spp.), Class Digenea, and Class Nematoda (Trichostrongyloidea, Strongyloides chapini, Protozoophaga obesa, and Capillaria hydrochoeri) were detected. Coccidia oocysts of Eimeria spp. and Cryptosporidium spp. were detected. The difference found was in the occurrence of S. chapini between anthropized and natural areas, as S. chapini was not detected in natural areas. Capybaras from anthropized areas showed a greater species richness of endoparasites, including species such as Fasciola hepatica and Cryptosporidium spp., that might have zoonotic potential.


Assuntos
Criptosporidiose , Cryptosporidium , Helmintos , Doenças dos Roedores , Animais , Brasil , Fezes , Roedores
16.
Rev Bras Parasitol Vet ; 30(4): e007021, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34669762

RESUMO

The present study attempted to evaluate the practical experience and methods employed by Brazilian veterinary practitioners for control of parasites. Twenty-one questions were asked of 403 veterinary practitioners based in different climatic zones with reference to parasite epidemiology from the country. Administration of a combination of drugs at three-month intervals was the most common regime recommended for prophylaxis against gastrointestinal helminths, with a single treatment repeated after 15 days. Routine prophylaxis against dog ectoparasites was recommended by 82.4% veterinary practitioners, and 46.6% changed the drug compound used. Monthly prophylaxic treatments for ectoparasites, using systemic, topical and/or collar-impregnated drugs, was recommended by 21.5% veterinary practitioners. Side-effects of ectoparasiticide-impregnated collars were suspected by 58% of the veterinary practitioners. Isoxazolines were the most frequently used chemical group to treat ectoparasites in dogs. Poor efficacy of fipronil in controlling ticks was suspected by 79.5% of the veterinary practitioners. The isoxazolines and combination of anthelmintic compounds are the most common drugs to prevent or treat ectoparasites and gastrointestinal nematodes, respectively. The suspect of the inefficacy of antiparasitic drugs is shared among the veterinary practitioners from part of Brazil. Guidelines are needed, specifically for the control of gastrointestinal helminths and ectoparasites in Brazilian dogs.


Assuntos
Doenças do Cão , Inseticidas , Nematoides , Parasitos , Carrapatos , Animais , Doenças do Cão/tratamento farmacológico , Doenças do Cão/prevenção & controle , Cães
17.
Syst Parasitol ; 75(3): 225-30, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20157796

RESUMO

A new coccidian species (Protozoa: Apicomplexa: Eimeriidae) obtained from masked yellowthroat Geothlypis aequinoctialis (Gmelin) is reported from Brazil. Isospora piacobrai n. sp. has oöcysts which are subspheroidal to ovoidal, measure 15.8 x 10.5 microm and have a smooth, bilayered wall c. 1.2 microm thick. A micropyle and oöcyst residuum are absent, but a polar granule is present. Its sporocysts are ovoidal and measure 15.8 x 10.5 microm. The Stieda body is knob-like and prominent, the substieda body large, trapezoidal and homogeneous, and the sporocyst residuum composed of granules of different sizes. Sporozoites are vermiform with one refractile body and a nucleus. This is the first description of an isosporoid coccidian infecting a bird of the family Parulidae.


Assuntos
Doenças das Aves/parasitologia , Isospora/classificação , Isospora/isolamento & purificação , Isosporíase/veterinária , Passeriformes/parasitologia , Animais , Brasil , Isospora/citologia , Isosporíase/parasitologia , Microscopia , Esporos de Protozoários/citologia
18.
Rev Bras Parasitol Vet ; 29(3): e012220, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32667504

RESUMO

In this commentary, the authors highlight the importance of basic research in the field of public health regarding the recent pandemic Covid-19, using tick-borne rickettsioses as an example. In addition, they alert politicians, government officials and managers of research funding agencies to increase the allocated financial resources to enhance basic research on public health in Brazil.


Assuntos
Infecções por Coronavirus , Pandemias , Pneumonia Viral , Infecções por Rickettsia/epidemiologia , Carrapatos/microbiologia , Zoonoses/microbiologia , Animais , Betacoronavirus , Brasil , COVID-19 , SARS-CoV-2
19.
Vet Parasitol Reg Stud Reports ; 21: 100413, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32862893

RESUMO

The Brazilian state of Maranhão is located in a transition area of the Amazon and Cerrado biomes, where there is a rich fauna of vertebrates. This study aimed to update the list of the ticks occurring in Maranhão, through a compilation of literature records and examination of three tick collections, plus the addition of unpublished collections of ticks from road-killed animals during recent years. Our results indicate that the tick fauna of Maranhão includes 26 species: seven in the family Argasidae (Antricola guglielmonei, Argas miniatus, Ornithodoros cavernicolous, Ornithodoros hasei, Ornithodoros mimon, Ornithodoros rietcorreai and Ornithodoros rudis); and 19 in the family Ixodidae (Amblyomma auricularium-provisional, Amblyomma cajennense sensu stricto, Amblyomma calcaratum, Amblyomma dissimile, Amblyomma geayi, Amblyomma longirostre, Amblyomma naponense, Amblyomma nodosum, Amblyomma oblongoguttatum, Amblyomma ovale, Amblyomma parvum, Amblyomma rotundatum, Amblyomma sculptum, Amblyomma triste, Dermacentor nitens, Ixodes luciae, Haemaphysalis juxtakochi, Rhipicephalus microplus, and Rhipicephalus sanguineus sensu lato). Eleven of the above species are reported for the first time in Maranhão. We consider previous reports of Ornithodoros talaje and Amblyomma pseudoconcolor in Maranhão as misidentification with O. hasei and A. auricularium, respectively. Until 1958, only 11 tick species were reported in Maranhão, with no additional reports until 2009. During 2010-2019, 15 additional species were reported. We also highlight the importance of ticks for public and veterinary health in Maranhão.


Assuntos
Distribuição Animal , Argasidae/fisiologia , Ixodidae/fisiologia , Animais , Argasidae/classificação , Brasil , Ixodidae/classificação , Estudos Retrospectivos
20.
Parasitol Res ; 105(3): 635-9, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19399519

RESUMO

Two new coccidian (Protozoa: Apicomplexa: Eimeriidae) species from the Brazilian tanager Ramphocelus bresilius dorsalis are reported in the current study. Isospora cadimi n. sp. oocysts are spheroidal to sub-spheroidal, 24.2 x 22.9 microm, with a smooth and bi-layered wall, approximately 1.1 microm. Micropyle, oocyst residuum, and polar granule are absent. Sporocysts are broadly ovoidal, 16.9 x 11.6 microm. Stieda and substieda bodies are present. Sporocyst residuum is present and sporozoites have refractile body and nucleus. Isospora navarroi n. sp. oocysts are spheroidal to sub-spheroidal, 21.4 x 20.6 microm, with a smooth and bi-layered wall, approximately 1.1 microm. Micropyle, oocyst residuum, and polar granule are absent. Sporocysts are ellipsoidal, 16.1 x 10.2 microm. Stieda and substieda bodies are present. Sporocyst residuum is present and sporozoites have a robust posterior refractile body.


Assuntos
Isospora/classificação , Isospora/isolamento & purificação , Passeriformes/parasitologia , Animais , Brasil , Isospora/citologia , Microscopia/métodos , Oocistos/citologia , Organelas
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