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1.
Parasite ; 19(4): 375-9, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23193522

RESUMO

A new species of haematozoa, Babesia ugwidiensis sp. nov. from a cormorant is described. This is the first species of piroplasm to be recorded from the Phalacrocoracidae and the relationship of this parasite to other Babesia spp. from marine hosts is discussed.


Assuntos
Babesia/classificação , Babesiose/veterinária , Doenças das Aves/parasitologia , Animais , Babesia/ultraestrutura , Babesiose/parasitologia , Aves , Parasitemia/parasitologia , Parasitemia/veterinária , África do Sul
2.
Korean J Parasitol ; 49(4): 437-40, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22355215

RESUMO

Babesia spp. were detected from 4 asymptomatic pukus captured on a game ranch in central Zambia in October 2008. Blood smears were examined in 4 species of aymptomatic free-ranging antelopes, namely the puku (Kobus vordanii), reedbuck (Redunca arundinum), bushbuck (Tragelaphus sylvaticus), and kudu (Tragelaphus strepsiceros), and showed the presence of Babesia parasites only in the puku. In the puku, the prevalence of babesiosis was estimated at 33.3% (n = 12), while the overall prevalence in all examined animals was 8.5% (n = 47). The parasites showed morphological characteristics of paired ring-like stages with the length varying between 1.61 µm and 3.02 µm (mean = 2.12 µm, n = 27; SD = 0.76 µm). Both the infected and non-infected pukus showed good body condition scores (BCS), while the dominant tick species detected from all animals were Rhipicephalus appendiculatus, Rhipicephalus spp., and Boophilus spp. To our knowledge this is the first report of Babesia spp. infection in pukus in Zambia. These findings suggest that wildlife could play an important role in the epidemiology of babesiosis in Zambia.


Assuntos
Antílopes/parasitologia , Babesia/isolamento & purificação , Babesiose/veterinária , Animais , Animais Selvagens/parasitologia , Vetores Aracnídeos/classificação , Doenças Assintomáticas , Babesia/ultraestrutura , Babesiose/epidemiologia , Babesiose/transmissão , Eritrócitos/parasitologia , Prevalência , Rhipicephalus/classificação , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/parasitologia , Infestações por Carrapato/veterinária , Carrapatos/parasitologia , Zâmbia/epidemiologia
3.
mSphere ; 5(5)2020 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-33055261

RESUMO

Babesia is an apicomplexan parasite of significance that causes the disease known as babesiosis in domestic and wild animals and in humans worldwide. Babesia infects vertebrate hosts and reproduces asexually by a form of binary fission within erythrocytes/red blood cells (RBCs), yielding a complex pleomorphic population of intraerythrocytic parasites. Seven of them, clearly visible in human RBCs infected with Babesia divergens, are considered the main forms and named single, double, and quadruple trophozoites, paired and double paired pyriforms, tetrad or Maltese Cross, and multiparasite stage. However, these main intraerythrocytic forms coexist with RBCs infected with transient parasite combinations of unclear origin and development. In fact, little is understood about how Babesia builds this complex population during its asexual life cycle. By combining cryo-soft X-ray tomography and video microscopy, main and transitory parasites were characterized in a native whole cellular context and at nanometric resolution. The architecture and kinetics of the parasite population was observed in detail and provide additional data to the previous B. divergens asexual life cycle model that was built on light microscopy. Importantly, the process of multiplication by binary fission, involving budding, was visualized in live parasites for the first time, revealing that fundamental changes in cell shape and continuous rounds of multiplication occur as the parasites go through their asexual multiplication cycle. A four-dimensional asexual life cycle model was built highlighting the origin of several transient morphological forms that, surprisingly, intersperse in a chronological order between one main stage and the next in the cycle.IMPORTANCE Babesiosis is a disease caused by intraerythrocytic Babesia parasites, which possess many clinical features that are similar to those of malaria. This worldwide disease is increasing in frequency and geographical range and has a significant impact on human and animal health. Babesia divergens is one of the species responsible for human and cattle babesiosis causing death unless treated promptly. When B. divergens infects its vertebrate hosts, it reproduces asexually within red blood cells. During its asexual life cycle, B. divergens builds a population of numerous intraerythrocytic (IE) parasites of difficult interpretation. This complex population is largely unexplored, and we have therefore combined three- and four-dimensional imaging techniques to elucidate the origin, architecture, and kinetics of IE parasites. Unveiling the nature of these parasites has provided a vision of the B. divergens asexual cycle in unprecedented detail and is a key step to develop control strategies against babesiosis.


Assuntos
Babesia/crescimento & desenvolvimento , Eritrócitos/parasitologia , Interações Hospedeiro-Patógeno , Trofozoítos/crescimento & desenvolvimento , Animais , Babesia/patogenicidade , Babesia/ultraestrutura , Babesiose/parasitologia , Bovinos , Doenças dos Bovinos/parasitologia , Eritrócitos/ultraestrutura , Humanos , Microscopia Eletrônica de Transmissão , Microscopia de Vídeo , Reprodução Assexuada , Imagem com Lapso de Tempo , Tomografia por Raios X , Trofozoítos/ultraestrutura
4.
Science ; 212(4492): 335-8, 1981 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-7209532

RESUMO

Adult Hereford (Bos taurus) cattle were protected from severe reactions and death caused by the tick-borne protozoan hemoparasite Babesia bovis, 3 months after vaccination with a cell culture--derived immunogen. The immunogen consisted of filtered, freeze-dried supernatant fluid collected from long-term cultures of Babesia bovis in vitro. It was reconstituted with saponin adjuvant and injected twice subcutaneously at 2-week intervals. Serum collected from vaccinated cattle caused thickening of the merozoite surface coat, aggregation, and lysis of merozoites in vitro. This reaction was identical to that caused by serum from immune carrier cattle suggesting that the protective antigen present in culture fluids is merozoite surface coat antigen. No mortality occurred among vaccinated cattle, whereas mortality among unvaccinated cattle and Babesia bigemina--immune cattle was 62.5 percent indicating that immunity to bovine babesiosis is species-specific.


Assuntos
Antígenos/administração & dosagem , Babesiose/prevenção & controle , Doenças dos Bovinos/prevenção & controle , Vacinação , Animais , Babesia/imunologia , Babesia/ultraestrutura , Bovinos , Meios de Cultura
5.
Vet Parasitol ; 151(2-4): 150-7, 2008 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-18083310

RESUMO

A novel large Babesia sp. from an infected dog was cultivated in vitro by microaerophilous stationary phase culture methodology. A primary culture initiated in enriched RPMI-1640 medium supplemented with 40% canine serum and incubated in a 2% oxygen environment supported parasite growth in vitro. Subsequent subcultures into enriched HL-1 medium with 20% fetal bovine serum also supported parasite propagation. Cultures were successfully introduced to 5% carbon dioxide in air atmosphere at passage 4. To date, the parasites have been continuously cultured through 35 passages, although the parasitemias are low, ranging from 0.2 to 0.3%. Parasites cultured in RPMI with canine serum were cryopreserved and successfully recovered from liquid nitrogen storage. The small subunit ribosomal rRNA gene sequence was identical in blood-derived and culture-derived parasites, differing in a single base position from the previously reported sequence for this Babesia sp. The ultrastructure of the parasite was consistent with that of other large Babesia spp., except that the spherical body contained numerous round particles unlike the inclusions previously described in Babesia spp.


Assuntos
Babesia/genética , Babesia/ultraestrutura , Babesiose/veterinária , Doenças do Cão/parasitologia , Animais , Babesia/classificação , Babesia/crescimento & desenvolvimento , Babesiose/parasitologia , Sequência de Bases , Células Cultivadas , Cães , Feminino , Genes de RNAr/genética , Microscopia Eletrônica de Transmissão/veterinária , Dados de Sequência Molecular , North Carolina , Especificidade da Espécie
6.
Parasitol Int ; 67(2): 190-195, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29155165

RESUMO

An attenuated live vaccine containing Babesia bovis and B. bigemina cultured in vitro with a serum-free medium was assessed for its clinical protection conferred of naïve cattle, under natural tick-challenge in a high endemicity zone to Babesia spp. Three groups of six animals were treated as follows: group I (GI) received a vaccine derived from parasites cultured with a free-serum medium; group II (GII) were immunized with the standard vaccine, with parasites cultured in a medium supplemented with 40% (v/v) bovine serum; and a control group (GIII) inoculated with non-infected bovine erythrocytes. Inocula were administered by IM route. Experimental animals were kept during 23days after vaccination in a cattle farm free of ticks and Babesia spp. Thereafter, cattle were moved to a high endemicity farm for natural exposure to Babesia spp. transmitted by Rhipicephalus microplus ticks. Protection against clinical babesiosis was observed in bovines belonging to GI (100%) and GII (83.33%), while the control animals (GIII) were not protected, and showed severe clinical signs, closely related to babesiosis, were observed for at least three consecutive days during the challenge. These were fever, anemia, which were measured simultaneously, and circulating parasites were detected by optic light microscopy. All cattle showed B. bovis and B. bigemina in stained blood films during the challenge; B. bovis antibody titers were higher than those to B. bigemina in GI and GII, and lower titers were determined in GIII. The protective capacity of the vaccine derived from B. bovis and B. bigemina cultured in vitro in a serum-free medium was demonstrated.


Assuntos
Babesia bovis/imunologia , Babesia/imunologia , Babesiose/prevenção & controle , Vacinas Atenuadas/administração & dosagem , Anemia/parasitologia , Animais , Anticorpos Antiprotozoários/sangue , Babesia/crescimento & desenvolvimento , Babesia/ultraestrutura , Babesia bovis/crescimento & desenvolvimento , Babesia bovis/ultraestrutura , Babesiose/sangue , Babesiose/imunologia , Babesiose/transmissão , Bovinos , Meios de Cultura Livres de Soro , Febre/parasitologia , Microscopia , Rhipicephalus/parasitologia , Temperatura de Transição , Vacinação/métodos , Vacinas Atenuadas/imunologia
7.
Parasit Vectors ; 10(1): 241, 2017 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-28514953

RESUMO

BACKGROUND: The United Kingdom is considered free of autochthonous transmission of canine babesiosis although cases are reported in dogs associated with recent travel abroad. During the winter months of 2015/16, a cluster of cases of disease in dogs with signs suggestive of canine babesiosis were reported in Harlow, Essex. METHODS: Babesia species were detected in dog blood samples by Giemsa staining of blood smears and by pan-piroplasm PCRs. Babesia species were also detected in extracts of tick DNA using pan-piroplasm PCRs. DNA sequencing and phylogenetic analysis was used to confirm the species of Babesia present in dog blood and tick samples. Tick species were identified by PCR-sequencing based on amplification of the cytochrome c oxidase subunit one (cox1) gene. Dermacentor reticulatus ticks were sampled from field sites in England and Wales. RESULTS: Blood smear analysis on samples taken from some of the affected dogs confirmed the presence of a large Babesia species within erythrocytes. A tick recovered from one of these cases was identified as Dermacentor reticulatus, a species with a limited distribution in England and Wales, but a known vector of canine babesiosis in continental Europe. Babesia canis was subsequently identified in blood samples obtained from three clinical cases (all dogs) within the area and from ticks associated with these dogs. A field survey detected 17 adult D. reticulatus ticks from one area visited by the affected dogs. Fourteen of these ticks were shown to be positive for the B. canis parasite, implicating them as a potential source for babesiosis in Harlow. In order to assess whether the parasite is present in more than one tick population, D. reticulatus ticks from across England and Wales were screened for the presence of Babesia species. In addition to the Harlow site, a further five locations where D. reticulatus is present were screened for Babesia species. Babesia was not detected from most sites tested but one tick from a single location in Wales was positive for B. canis. CONCLUSIONS: Infection with B. canis was confirmed in a number of dogs in Harlow, Essex, with no history of travel outside of the country. The same pathogen was identified in field-caught D. reticulatus ticks in the same area and is considered the likely source of infection. This highlights the need for vigilance by veterinary surgeons for future outbreaks of tick-borne disease in dogs.


Assuntos
Babesia/isolamento & purificação , Babesiose/epidemiologia , Surtos de Doenças/veterinária , Doenças do Cão/epidemiologia , Carrapatos/parasitologia , Animais , Babesia/classificação , Babesia/genética , Babesia/ultraestrutura , Babesiose/sangue , Babesiose/parasitologia , Babesiose/transmissão , Dermacentor/parasitologia , Doenças do Cão/parasitologia , Cães , Complexo IV da Cadeia de Transporte de Elétrons/genética , Filogenia , Reação em Cadeia da Polimerase , Estações do Ano , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/veterinária , Reino Unido/epidemiologia
8.
Int J Parasitol ; 36(7): 779-89, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16725142

RESUMO

The morphologic, ultrastructural and genotypic characteristics of Babesia duncani n.sp. are described based on the characterization of two isolates (WA1, CA5) obtained from infected human patients in Washington and California. The intraerythrocytic stages of the parasite are morphologically indistinguishable from Babesia microti, which is the most commonly identified cause of human babesiosis in the USA. Intraerythrocytic trophozoites of B. duncani n.sp. are round to oval, with some piriform, ring and ameboid forms. Division occurs by intraerythrocytic schizogony, which results in the formation of merozoites in tetrads (syn. Maltese cross or quadruplet forms). The ultrastructural features of trophozoites and merozoites are similar to those described for B. microti and Theileria spp. However, intralymphocytic schizont stages characteristic of Theileria spp. have not been observed in infected humans. In phylogenetic analyses based on sequence data for the complete18S ribosomal RNA gene, B. duncani n.sp. lies in a distinct clade that includes isolates from humans, dogs and wildlife in the western United States but separate from Babesia sensu stricto, Theileria spp. and B. microti. ITS2 sequence analysis of the B. duncani n.sp. isolates (WA1, CA5) show that they are phylogenetically indistinguishable from each other and from two other human B. duncani-type parasites (CA6, WA2 clone1) but distinct from other Babesia and Theileria species sequenced. This analysis provides robust molecular support that the B. duncani n.sp. isolates are monophyletic and the same species. The morphologic characteristics together with the phylogenetic analysis of two genetic loci support the assertion that B. duncani n.sp. is a distinct species from other known Babesia spp. for which morphologic and sequence information are available.


Assuntos
Babesia/classificação , Babesiose/parasitologia , Animais , Babesia/genética , Babesia/ultraestrutura , Sequência de Bases , DNA de Protozoário/imunologia , DNA Espaçador Ribossômico/genética , Genes de Protozoários , Humanos , Microscopia Eletrônica , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase/métodos , RNA de Protozoário/genética , RNA Ribossômico 18S/genética
9.
Vet Parasitol ; 138(1-2): 103-11, 2006 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-16524663

RESUMO

Small piroplasms as a cause of canine babesiosis have usually been identified as Babesia gibsoni. Recent genetic studies suggested that small piroplasms are more likely comprised of at least three genotypically distinct species. In southern California, canine babesiosis caused by a small piroplasm has been documented since 1990. Morphological characteristics of this parasite include a small (0.3-3.0 microm) intraerythrocytic merozoite stage with predominantly ring, piriform, tetrad, amoeboid, or anaplasmoid forms. Transmission electron microscopic images of merozoites demonstrate the presence of an apical complex consisting of an inner subplasmalemmal membrane and rhoptries. Based on phylogenetic analyses of the 18S rRNA and the ITS-2 genes, the Californian small piroplasm isolate is more closely related to piroplasm isolates from wildlife and humans in the western United States than it is to B. gibsoni. Molecular and morphologic evidence supports naming the small piroplasm from southern California as a distinct species, Babesia conradae.


Assuntos
Babesia/classificação , Babesia/isolamento & purificação , Babesiose/veterinária , Doenças do Cão/parasitologia , Eritrócitos/parasitologia , Animais , Babesia/genética , Babesia/ultraestrutura , Babesiose/parasitologia , California , Primers do DNA/química , DNA de Protozoário/química , DNA Ribossômico/química , DNA Espaçador Ribossômico/genética , Cães , Eritrócitos/patologia , Microscopia Eletrônica de Transmissão/veterinária , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 18S/genética
10.
J Parasitol ; 92(2): 333-40, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16729690

RESUMO

A Babesia sp. isolated from eastern cottontail rabbits (Sylvilagus floridanus) is morphologically similar and genetically identical, based on SSU rRNA gene comparisons, to 2 agents responsible for human babesiosis in the United States. This zoonotic agent is closely related to the European parasite, Babesia divergens. The 2 organisms were characterized by in vitro comparisons. In vitro growth of the rabbit Babesia sp. was supported in human and cottontail rabbit erythrocytes, but not in bovine cells. Babesia divergens was supported in vitro in bovine and human erythrocytes, but not in cottontail rabbit cells. Morphometric analysis classifies B. divergens as a small babesia in bovine erythrocytes, but the parasite exceeds this size in human erythrocytes. The rabbit Babesia sp. is large, the same size in both human or rabbit erythrocytes, and is significantly larger than B. divergens. Eight or more rabbit Babesia sp. parasites may occur within a single erythrocyte, sometimes in a floret array, unlike B. divergens. The erythrocyte specificity and morphological differences reported in this study agree with previous in vivo results and validate the use of in vitro methods for characterization of Babesia species.


Assuntos
Babesia/fisiologia , Babesiose/parasitologia , Eritrócitos/parasitologia , Coelhos/parasitologia , Zoonoses , Animais , Babesia/ultraestrutura , Bovinos , Interações Hospedeiro-Parasita , Humanos , Coelhos/sangue , Especificidade da Espécie , Zoonoses/parasitologia
11.
J Parasitol ; 92(5): 1104-7, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17152960

RESUMO

Babesia Washington-1 (WA1) is a newly identified intraerythrocyte infectious agent of human babesiosis in the western United States. The purpose of the present study is to describe the ultrastructural changes in affected erythrocytes during the infectious process in a susceptible animal model, the golden Syrian hamster. Two, 1-mo-old female hamsters were inoculated intraperitoneally (i.p.) with 1.8 x 10(9) Babesia WA1-infected erythrocytes originally isolated from a human case and serially passaged in hamsters. Saphenous vein blood samples (20 microl) were collected at 0, 24, 36, 48, 60, 72, 84, and 96 hr postinoculation (PI). Parasitemia was determined at each time interval by quick staining of blood smears showing 0, 2.5, 5, 10, 12.5, 22.5, 70, and almost 100% parasitemic erythrocytes at the corresponding PI time interval, respectively. Animals showed weakness and dehydration 72 hr PI inoculation, and were killed by 96 hr PI. Selected blood samples from 0, 24, 48, 72, and 96 hr were fixed in cacodylate buffer, dehydrated in ethanol gradients, resin embedded, and then thin sectioned and stained with uranyl acetate and lead citrate for transmission electron microscopy or gold-coated for scanning electron microscopy (SEM). Shape and surface membrane changes in erythrocytes were demonstrated by SEM and were more evident at 72 and 96 hr PI. Infected erythrocytes underwent changes in shape 24 hr PI, from few protrusions to several perforations, some of them resembling a "swiss cheese" appearance 96 hr PI. Several erythrocytes had irregular surface membranes and Babesia WA1 organisms were seen at different stages of development within erythrocytes, from single trophozoites to several merozoites (young trophozoites), some of them dividing to form typical tetrads. In general, Babesia WAI induced severe morphological changes in the erythrocytes, and these changes were more evident in almost all infected cells 96 hr PI.


Assuntos
Babesia/ultraestrutura , Babesiose/parasitologia , Eritrócitos/parasitologia , Animais , Babesia/patogenicidade , Babesiose/sangue , Babesiose/patologia , Cricetinae , Modelos Animais de Doenças , Membrana Eritrocítica/parasitologia , Membrana Eritrocítica/patologia , Membrana Eritrocítica/ultraestrutura , Eritrócitos/patologia , Eritrócitos/ultraestrutura , Feminino , Humanos , Mesocricetus , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Vacúolos/patologia , Vacúolos/ultraestrutura , Virulência
12.
Ticks Tick Borne Dis ; 7(6): 1274-1279, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27430965

RESUMO

The invasive form of the apicomplexan parasite Babesia divergens, the free merozoite, invades the erythrocytes of host vertebrates, leading to significant pathology. Although invasion is an active process critical for parasite survival, it is not yet entirely understood. Using techniques to isolate the viable free merozoite, as well as electron microscopy, we undertook a detailed morphological study and explored the sub-cellular structure of the invasive B. divergens free merozoite after it had left the host cell. We examined characteristic apicomplexan features such as the apicoplast, the inner and discontinuous double membrane complex, and the apical complex; some aspects of erythrocyte entry by B. divergens were also defined by electron microscopy. This study adds to our understanding of B. divergens free merozoites and their invasion of human erythrocytes.


Assuntos
Babesia/ultraestrutura , Merozoítos/ultraestrutura
13.
Int J Parasitol ; 35(9): 1031-5, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15979628

RESUMO

A Babesia gibsoni infected bitch was mated with an uninfected dog in order to determine whether this parasite could be vertically transmitted. The bitch delivered a litter of four live and one stillborn pup. The four pups died from congenital babesiosis between 14 and 39 days post-birth. Babesia gibsoni DNA was detected in tissue from all five pups. These results show that vertical transmission occurred by the uterine route and not via the transmammary route. This is the first confirmed report of transplacental Babesia infection in any animal species.


Assuntos
Babesiose/transmissão , Babesiose/veterinária , Doenças do Cão/parasitologia , Complicações Parasitárias na Gravidez , Animais , Animais Recém-Nascidos , Anticorpos Antiprotozoários/biossíntese , Babesia/imunologia , Babesia/isolamento & purificação , Babesia/ultraestrutura , Babesiose/congênito , DNA de Protozoário/análise , Cães , Feminino , Transmissão Vertical de Doenças Infecciosas , Parasitemia/veterinária , Gravidez , Efeitos Tardios da Exposição Pré-Natal , Natimorto/veterinária
14.
Am J Clin Pathol ; 73(1): 107-9, 1980 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7188717

RESUMO

Blood smears from 13 patients infected with Babesia microti were reviewed to define the range of morphologic characteristics of the organism. Organisms resembling rings of Plasmodium falciparum were the predominant forms in all patients' blood smears. Babesia microti and Plasmodium spp. may be differentiated by the presence of pigment deposits in erythrocytes parasitized with mature stages of Plasmodium.


Assuntos
Babesia/ultraestrutura , Babesiose/microbiologia , Animais , Babesiose/sangue , Cromatina/ultraestrutura , Eritrócitos/microbiologia , Humanos
15.
Am J Trop Med Hyg ; 68(3): 334-40, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12685641

RESUMO

We evaluated the growth inhibitory effect of triclosan, which has recently been reported to inhibit the growth of Plasmodium species and Toxoplasma gondii, on bovine and equine Babesia parasites in in vitro cultures The growth of Babesia bovis and B. bigemina was significantly inhibited in the presence of 100 microg/ml of triclosan, while B. caballi and B. equi were susceptible to as low as 50 microg/ml. Babesia bigemina and B. caballi were completely cleared as early as on the first and second day of the treatment, respectively. These parasites did not exhibit any growth in the subsequent five-day period of subculture without triclosan. Drug-treated parasites appeared pycnotic and atypically shaped, and ultrastructurally showed pronounced vacuolations, leading to complete destruction of parasites. Light microscopy showed that used concentrations of triclosan showed no toxicity against the host cells. The results suggest that triclosan can be used for chemotherapy of babesiosis.


Assuntos
Antiprotozoários/farmacologia , Babesia/efeitos dos fármacos , Bovinos/parasitologia , Cavalos/parasitologia , Triclosan/farmacologia , Animais , Babesia/crescimento & desenvolvimento , Babesia/ultraestrutura , Microscopia Eletrônica
16.
Acta Trop ; 36(3): 229-41, 1979 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-43086

RESUMO

The formation of sporozoites of Babesia canis was studied by light- and electron microscopy in the salivary gland cells of adult female ticks from the 2nd day after attachment until 1 day after detachment. It was found that this process was initiated by the binary division of kinetes that had already entered or entered during the period examined. During division the kinetes (15 X 2.5 microns) lost their typical organelles, reduced their three-layered pellicle to a single membrane and became spherical. After nuclear division and a further time-lag cell division occurred, giving rise to two cells in which this process was repeated. After numerous binary divisions the parasites acquired more and more closely the shape of the later infectious, pyriform sporozoite. These sporozoites measured about 2.5 X 1.5 microns and also had a three-layered pellicle, with rhoptries and a few micronemes, but never contained "spherical bodies". The formation process needed about 2--3 days so that the transmission to the dog could be carried out while the tick engorges and this is probably the stimulation for the development. Finally the cytological features of this sporozoite formation were compared to those in the Theileria species studied by our group.


Assuntos
Vetores Aracnídeos , Babesia/crescimento & desenvolvimento , Dermacentor/microbiologia , Carrapatos/microbiologia , Animais , Babesia/ultraestrutura , Divisão Celular , Feminino , Organoides/ultraestrutura , Glândulas Salivares/microbiologia , Esporos/crescimento & desenvolvimento , Esporos/ultraestrutura
17.
Braz J Med Biol Res ; 27(11): 2591-8, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7549981

RESUMO

1. We describe the isolation of viable merozoites from erythrocytes infected with Babesia bovis or Babesia bigemina organisms by ammonium chloride lysis. 2. Parasite morphology was examined by both light and transmission electron microscopy. Erythrocyte-free parasites maintain their viability and infectivity, retain their antigenicity and are suitable for use in the indirect fluorescent antibody assay.


Assuntos
Babesia bovis/isolamento & purificação , Babesia/isolamento & purificação , Eritrócitos/parasitologia , Cloreto de Amônio , Animais , Anticorpos Antiprotozoários/análise , Babesia/imunologia , Babesia/ultraestrutura , Babesia bovis/imunologia , Babesia bovis/ultraestrutura , Bovinos , Imunofluorescência , Microscopia Eletrônica
18.
J Vet Diagn Invest ; 16(3): 229-33, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15152839

RESUMO

Canine babesiosis is a tick-borne parasitic disease caused by the intraerythrocytic parasites, Babesia canis and Babesia gibsoni. A lethargic, weak, American Staffordshire Terrier (pit bull) dog, which had regenerative, normocytic, normochromic anemia, was shown by polymerase chain reaction analysis to be infected with B. gibsoni. Transmission electron microscopy of ethylenediamine tetraacetic acid-treated blood disclosed many well-preserved, intraerythrocytic babesia trophozoites. Four morphologic forms of babesia trophozoites are described (small spheres, small rods, irregular forms lacking pseudoinclusions, and large spheres having pseudoinclusions) and are compared with intraerythrocytic forms of B. canis and B. gibsoni described in other light and electron microscopic studies of in vivo and in vitro Babesia infections. This is the first detailed transmission electron microscopic study of canine B. gibsoni-infected red blood cells in North America.


Assuntos
Babesia/crescimento & desenvolvimento , Babesiose/veterinária , Doenças do Cão/parasitologia , Anemia/sangue , Anemia/parasitologia , Anemia/patologia , Anemia/veterinária , Animais , Babesia/genética , Babesia/ultraestrutura , Babesiose/sangue , Babesiose/parasitologia , Babesiose/patologia , DNA de Protozoário/química , DNA de Protozoário/genética , Doenças do Cão/sangue , Doenças do Cão/patologia , Cães , Eritrócitos/parasitologia , Eritrócitos/ultraestrutura , Feminino , Microscopia Eletrônica/veterinária , Reação em Cadeia da Polimerase/veterinária
19.
J Parasitol ; 84(2): 422-4, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9576519

RESUMO

Babesia bennetti sp. nov. is described as a new species of piroplasm parasitizing the yellow-legged gull Larus cachinnans. This is the first report of Babesia for this family of birds. Double infections in the erythrocytes were common. The udder cow forms described in Babesia peircei also were found in this species. The typical "X" forms are rarely seen, with merozoites commonly found in pairs as tetrads.


Assuntos
Babesia/classificação , Babesiose/parasitologia , Doenças das Aves/parasitologia , Animais , Babesia/ultraestrutura , Aves , Eritrócitos/parasitologia , Ilhas do Mediterrâneo , Espanha
20.
J Parasitol ; 79(3): 424-34, 1993 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8501601

RESUMO

Babesia odocoilei continuously cultured in white-tailed deer (Odocoileus virginianus) erythrocytes was examined by transmission and scanning electron microscopy. Merozoites, trophozoites, intermediate-stage forms, and dividing forms were observed. Merozoites possessed a single nucleus, inner membrane complex, rhoptries, free ribosomes, rough endoplasmic reticulum, and single membrane-bound vesicles. Trophozoites lacked an inner membrane complex and rhoptries. Intermediate stages were characterized by distinct segments of inner membrane complex. Dividing forms ranged from cells with an elongated nucleus to mature daughter cells joined by a ringlike structure. Babesia odocoilei was characterized by its close proximity to the erythrocyte membrane, membranous structures resembling feeding organelles, and reproduction via a method resembling budding sensu stricto.


Assuntos
Babesia/ultraestrutura , Babesiose/parasitologia , Cervos/parasitologia , Eritrócitos/parasitologia , Animais , Babesia/citologia , Babesia/crescimento & desenvolvimento , Divisão Celular , Cervos/sangue , Microscopia Eletrônica , Microscopia Eletrônica de Varredura
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