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Martin Kváč - One of the best experts on this subject based on the ideXlab platform.

  • cryptosporidium ratti n sp apicomplexa Cryptosporidiidae and genetic diversity of cryptosporidium spp in brown rats rattus norvegicus in the czech republic
    Parasitology, 2021
    Co-Authors: Jana Jezkova, Nikola Holubova, Roman Konecný, John Mcevoy, Bohumil Sak, Lihua Xiao, Jitka Prediger, Michael Rost, Yaoyu Feng, Martin Kváč
    Abstract:

    The diversity and biology of Cryptosporidium that is specific for rats (Rattus spp.) are not well studied. We examined the occurrence and genetic diversity of Cryptosporidium spp. in wild brown rats (Rattus norvegicus) by microscopy and polymerase chain reaction (PCR)/sequencing targeting the small subunit rDNA (SSU), actin and HSP70 genes. Out of 343 faecal samples tested, none were positive by microscopy and 55 were positive by PCR. Sequence analysis of SSU gene revealed the presence of Cryptosporidium muris (n = 4), C. andersoni (n = 3), C. ryanae (n = 1), C. occultus (n = 3), Cryptosporidium rat genotype I (n = 23), Cryptosporidium rat genotype IV (n = 16) and novel Cryptosporidium rat genotype V (n = 5). Spherical oocysts of Cryptosporidium rat genotype I obtained from naturally-infected rats, measuring 4.4-5.4 μm × 4.3-5.1 μm, were infectious to the laboratory rats, but not to the BALB/c mice (Mus musculus) nor Mongolian gerbils (Meriones unguiculatus). The prepatent period was 3 days post infection and the patent period was longer than 30 days. Naturally- and experimentally-infected rats showed no clinical signs of disease. Percentage of nucleotide similarities at the SSU, actin, HSP70 loci between C. ratti n. sp. and the rat derived C. occultus and Cryptosporidium rat genotype II, III, IV, and V ranged from 91.0 to 98.1%. These genetic variations were similar or greater than that observed between closely related species, i.e. C. parvum and C. erinacei (93.2-99.5%). Our morphological, genetic and biological data support the establishment of Cryptosporidium rat genotype I as a new species, Cryptosporidium ratti n. sp.

  • description of cryptosporidium ornithophilus n sp apicomplexa Cryptosporidiidae in farmed ostriches
    Parasites & Vectors, 2020
    Co-Authors: Nikola Holubova, Roman Konecný, John Mcevoy, Bohumil Sak, Martin Kváč, Lenka Tůmova, Adela Hejzlarova
    Abstract:

    Avian cryptosporidiosis is a common parasitic disease that is caused by five species, which are well characterised at the molecular and biological level, and more than 18 genotypes for which we have limited information. In this study, we determined the occurrence and molecular characteristics of Cryptosporidium spp. in farmed ostriches in the Czech Republic. The occurrence and genetic identity of Cryptosporidium spp. were analysed by microscopy and PCR/sequencing of the small subunit rRNA, actin, HSP70 and gp60 genes. Cryptosporidium avian genotype II was examined from naturally and experimentally infected hosts and measured using differential interference contrast. The localisation of the life-cycle stages was studied by electron microscopy and histologically. Infectivity of Cryptosporidium avian genotype II for cockatiels (Nymphicus hollandicus (Kerr)), chickens (Gallus gallus f. domestica (L.)), geese (Anser anser f. domestica (L.)), SCID and BALB/c mice (Mus musculus L.) was verified. A total of 204 individual faecal samples were examined for Cryptosporidium spp. using differential staining and PCR/sequencing. Phylogenetic analysis of small subunit rRNA, actin, HSP70 and gp60 gene sequences showed the presence of Cryptosporidium avian genotype II (n = 7) and C. ubiquitum Fayer, Santin & Macarisin, 2010 IXa (n = 5). Only ostriches infected with Cryptosporidium avian genotype II shed oocysts that were detectable by microscopy. Oocysts were purified from a pooled sample of four birds, characterised morphometrically and used in experimental infections to determine biological characteristics. Oocysts of Cryptosporidium avian genotype II measure on average 6.13 × 5.15 μm, and are indistinguishable by size from C. baileyi Current, Upton & Haynes, 1986 and C. avium Holubova, Sak, Horcickova, Hlaskova, Květoňova, Menchaca, McEvoy & Kvac, 2016. Cryptosporidium avian genotype II was experimentally infectious for geese, chickens and cockatiels, with a prepatent period of four, seven and eight days post-infection, respectively. The infection intensity ranged from 1000 to 16,000 oocysts per gram. None of the naturally or experimentally infected birds developed clinical signs in the present study. The molecular and biological characteristics of Cryptosporidium avian genotype II, described here, support the establishment of a new species, Cryptosporidium ornithophilus n. sp.

  • cryptosporidium occultus sp n apicomplexa Cryptosporidiidae in rats
    European Journal of Protistology, 2018
    Co-Authors: Roman Konecný, Lenka Hlaskova, John Mcevoy, Michaela Horčičková, Martin Kváč, Jana Jezkova, Gabriela Vlnata, Bohumil Sak
    Abstract:

    Cryptosporidium parvum VF383 has been reported in humans, domesticated ruminants, and wild rats worldwide and described under several names including Cryptosporidium suis-like, based on its close phylogenetic relationship to C. suis. Unlike C. suis, however, it has never been detected in pigs. In the present work, C. parvum VF383 originating from wild brown rats was not infectious for piglets or calves but was infectious for laboratory brown rats, BALB/c mice, and Mongolian gerbils. The prepatent period was 4-5 days for all rodents. The patent period was longer for rats (>30 days) than other rodents (<20 days). None of the rodents developed clinical signs of infection. In all rodents, life cycle stages were detected in the colon by histology and electron microscopy. Oocysts were morphometrically similar to those of C. parvum and smaller than those of C. suis, measuring 5.20 × 4.94 μm. Phylogenetic analyses of 18S rRNA, actin, and HSP70 gene sequences revealed C. parvum VF383 to be genetically distinct from, C. suis, and other described species of Cryptosporidium. Morphological, genetic, and biological data support the establishment of C. parvum VF383 as a new species, and we propose the name Cryptosporidium occultus sp. n.

  • Cryptosporidium testudinis sp. n., Cryptosporidium ducismarci Traversa, 2010 and Cryptosporidium tortoise genotype III (Apicomplexa: Cryptosporidiidae) in tortoises.
    Folia Parasitologica, 2016
    Co-Authors: Jana Jezkova, Lenka Hlaskova, Michaela Horčičková, Bohumil Sak, Martin Kváč, Dana Kvetonova, Jan Novák, Lada Hofmannová, John Mcevoy
    Abstract:

    Understanding of the diversity of species of Cryptosporidium Tyzzer, 1910 in tortoises remains incomplete due to the limited number of studies on these hosts. The aim of the present study was to characterise the genetic diversity and biology of cryptosporidia in tortoises of the family Testudinidae Batsch. Faecal samples were individually collected immediately after defecation and were screened for presence of cryptosporidia by microscopy using aniline-carbol-methyl violet staining, and by PCR amplification and sequence analysis targeting the small subunit rRNA (SSU), Cryptosporidium oocyst wall protein (COWP) and actin genes. Out of 387 faecal samples from 16 tortoise species belonging to 11 genera, 10 and 46 were positive for cryptosporidia by microscopy and PCR, respectively. All samples positive by microscopy were also PCR positive. Sequence analysis of amplified genes revealed the presence of the Cryptosporidium tortoise genotype I (n = 22), C. ducismarci Traversa, 2010 (n = 23) and tortoise genotype III (n = 1). Phylogenetic analyses of SSU, COWP and actin gene sequences revealed that Cryptosporidium tortoise genotype I and C. ducismarci are genetically distinct from previously described species of Cryptosporidium. Oocysts of Cryptosporidium tortoise genotype I, measuring 5.8-6.9 µm × 5.3-6.5 µm, are morphologically distinguishable from C. ducismarci, measuring 4.4-5.4 µm × 4.3-5.3 µm. Oocysts of Cryptosporidium tortoise genotype I and C. ducismarci obtained from naturally infected Russian tortoises (Testudo horsfieldii Gray) were infectious for the same tortoise but not for Reeve's turtles (Mauremys reevesii [Gray]), common garter snake (Thamnophis sirtalis [Linnaeus]), zebra finches (Taeniopygia guttata [Vieillot]) and SCID mice (Mus musculus Linnaeus). The prepatent period was 11 and 6 days post infection (DPI) for Cryptosporidium tortoise genotype I and C. ducismarci, respectively; the patent period was longer than 200 days for both cryptosporidia. Naturally or experimentally infected tortoises showed no clinical signs of disease. Our morphological, genetic, and biological data support the establishment of Cryptosporidium tortoise genotype I as a new species, Cryptosporidium testudinis sp. n., and confirm the validity of C. ducismarci as a separate species of the genus Cryptosporidium.

  • RESEARCH ARTICLE Cryptosporidium proliferans n. sp. (Apicomplexa: Cryptosporidiidae): Molecular and Biological Evidence of Cryptic Species within Gastric Cryptosporidium of Mammals
    2016
    Co-Authors: Martin Kváč, Lenka Hlaskova, Bohumil Sak, Jana Jezkova, Jiři Vitovec, Nikola Havrdova, Tereza Daňkova, Jiří K, Ynes Ortega, Lihua Xiao
    Abstract:

    The morphological, biological, and molecular characteristics of Cryptosporidiummuris strain TS03 are described, and the species name Cryptosporidium proliferans n. sp. is pro-posed. Cryptosporidium proliferans obtained from a naturally infected East African mole rat (Tachyoryctes splendens) in Kenya was propagated under laboratory conditions in rodents (SCID mice and southern multimammate mice,Mastomys coucha) and used in experiments to examine oocyst morphology and transmission. DNA from the propagated C. proliferans isolate, and C. proliferans DNA isolated from the feces of an African buffalo (Syncerus caf-fer) in Central African Republic, a donkey (Equus africanus) in Algeria, and a domestic horse (Equus caballus) in the Czech Republic were used for phylogenetic analyses. Oocysts of C. proliferans are morphologically distinguishable from C. parvum and C.muris HZ206, measuring 6.8–8.8 (mean = 7.7 μm) × 4.8–6.2 μm (mean = 5.3) with a length to width ratio of 1.48 (n = 100). Experimental studies using an isolate originated from T. splen

Carlos Wilson Gomes Lopes - One of the best experts on this subject based on the ideXlab platform.

  • oocysts of cryptosporidium tyzzer 1907 apicomplexa Cryptosporidiidae in brown mussels perna perna l 1758 mollusca bivalviae in ponta do tingui mangaratiba rj a biomarker of environmental contamination
    2013
    Co-Authors: Jose De Souza Herdy, Sergian Vianna Cardozo, Bruno Pereira Berto, Tatiana Silveira, Feijo Cardozo, Carlos Wilson Gomes Lopes
    Abstract:

    Cardozo SV, Berto BP, Cardozo TSF, Mesquisa EFM, Lopes CWG. 2013. Oocysts of Cryptosporidium Tyzzer, 1907 (Apicomplexa: Cryptosporidiidae) in brown mussels Perna perna L., 1758 (Mollusca: Bivalviae) in Ponta do Tingui, Mangaratiba, RJ: A biomarker of environmental contamination [Oocistos de Cryptosporidium Tyzzer, 1907 (Apicomplexa: Cryptosporidiidae) em mexilhoes Perna perna L., 1758 (Mollusca: Bivalviae) na Ponta do Tingui, Mangaratiba, RJ: Um biomarcador de contaminacao ambiental.] Coccidia 1, 32-38. Curso de Especializacao em Ciencias do Laboratorio Clinico e Diagnostico in vitro, Escola de Ciencias da Saude, Universidade do Grande Rio. Rua Prof. Jose de Souza Herdy, 1160, 25071202, Duque de Caxias, RJ, Brasil. E-mail: sergian.cardozo@unigranrio. com.br Discharge of treated or untreated sewage into rivers and seas undermines the quality of the water, besides introducing human or animal enteric pathogens and contribute to higher levels of organic nutrients in these areas. The aim of this work was to use oocysts of Cryptosporidium Tyzzer, 1907 as a biomarker of environmental contamination in bivalve molluscs Perna perna L., 1758 collected in Ponta do Tingui, Mangaratiba, RJ. For this, the mussels collected were processed in the laboratory, being detached from their shells and macerated. The biomass was diluted in distilled water and filtered to obtain a water-biomass solution, which was subjected to formalinether sedimentation technique, with observation in bright field, and safranin-methylene blue staining technique. All samples were positive for Cryptosporidium oocysts. Forty oocysts were measured and compared with Cryptosporidium hominis Morgan-Ryan, Fall, Ward, Hijjawi, Sulaiman, Fayer, Thompson,Olson, Lal, Xiao, 2002 oocysts by using histograms and linear regressions. MorphomeOocysts of Cryptosporidium Tyzzer, 1907 (Apicomplexa: Cryptosporidiidae) in brown mussels Perna perna L., 1758 (Mollusca: Bivalviae) in Ponta do Tingui, Mangaratiba, RJ: A biomarker of environmental contamination Sergian Vianna Cardozo | Bruno Pereira Berto | Tatiana Silveira Feijo Cardozo | Eliana de Fatima Marques de Mesquita | Carlos Wilson Gomes Lopes

  • experimental transmission of cryptosporidium baileyi apicomplexa Cryptosporidiidae isolated of broiler chicken to japanese quail coturnix japonica
    Revista brasileira de parasitologia veterinaria = Brazilian journal of veterinary parasitology : Orgao Oficial do Colegio Brasileiro de Parasitologia , 2005
    Co-Authors: Sergian V Cardozo, Carlos Wilson Gomes Lopes
    Abstract:

    In this work, oocysts of Cryptosporidium baileyi were isolated and identified in broiler chickens from three different Municipalities of the State of Rio de Janeiro, where they were isolated and identified by using the centrifuge- flotation technique associated to bright-field. Staining techniques, such as: modified Ziehl-Neelsen and safranin-methylene blue, were carried out to confirm natural infection. Oocysts of C. baileyi from broiler chickens were able to infect Coccidia-free Japanese quails, by observation of endogenous stages at histological sections, and the elimination of oocysts in the feces with prepatent period of seven days and patent period of 21 days after infection. Oocysts of C. baileyi from broiler chickens and Japanese quails were similar on bright-field microscopy. With respect to the staining techniques used in this research, all of them left to significant changes in length and width of oocysts, but shape indexes were maintained. Bright-field microscopy was the best technique for oocysts comparison shed by broiler chickens and Japanese quail because of no different among oocysts were observed.

  • transmissao experimental de cryptosporidium baileyi apicomplexa Cryptosporidiidae isolado de frango de corte a codorna japonesa coturnix japonica
    Revista Brasileira De Parasitologia Veterinaria, 2005
    Co-Authors: Sergian V Cardozo, Walter Leira Teixeira Filho, Carlos Wilson Gomes Lopes
    Abstract:

    2 ABSTRACT: - CARDOZO, S.V.; TEIXEIRA FILHO, W.L.; LOPES, C.W.G. (Experimental transmission of Cryptosporidum baileyi (Apicomplexa: Cryptosporidiidae) isolated of broiler chicken to Japanese quail (Coturnix japonica)). Transmissao experimental de Cryptosporidium baileyi (Apicomplexa: Cryptoporidiidae) isolado de frango de corte a codorna japonesa. Revista Brasileira de Parasitologia Veterinaria, v. 14, n. 3, p. 119-124, 2005. Universidade Federal Rural do Rio de Janeiro, Departamento de Parasitologia Animal, Km 7 da BR 465, Seropedica, RJ, Brazil, 23890-000. E-mail: lopescwg@ufrrj.br In this work, oocysts of Cryptosporidium baileyi were isolated and identified in broiler chickens from three different Municipalities of the State of Rio de Janeiro, where they were isolated and identified by using the centrifuge- flotation technique associated to bright-field. Staining techniques, such as: modified Ziehl-Neelsen and safranin- methylene blue, were carried out to confirm natural infection. Oocysts of C. baileyi from broiler chickens were able to infect Coccidia-free Japanese quails, by observation of endogenous stages at histological sections, and the elimination of oocysts in the feces with prepatent period of seven days and patent period of 21 days after infection. Oocysts of C. baileyi from broiler chickens and Japanese quails were similar on bright-field microscopy. With respect to the staining techniques used in this research, all of them left to significant changes in length and width of oocysts, but shape indexes were maintained. Bright-field microscopy was the best techinique for oocysts comparison shed by broiler chickens and Japanese quail because of no different among oocysts were observed.

Fernando Cristino Barbosa - One of the best experts on this subject based on the ideXlab platform.

Lihua Xiao - One of the best experts on this subject based on the ideXlab platform.

  • cryptosporidium ratti n sp apicomplexa Cryptosporidiidae and genetic diversity of cryptosporidium spp in brown rats rattus norvegicus in the czech republic
    Parasitology, 2021
    Co-Authors: Jana Jezkova, Nikola Holubova, Roman Konecný, John Mcevoy, Bohumil Sak, Lihua Xiao, Jitka Prediger, Michael Rost, Yaoyu Feng, Martin Kváč
    Abstract:

    The diversity and biology of Cryptosporidium that is specific for rats (Rattus spp.) are not well studied. We examined the occurrence and genetic diversity of Cryptosporidium spp. in wild brown rats (Rattus norvegicus) by microscopy and polymerase chain reaction (PCR)/sequencing targeting the small subunit rDNA (SSU), actin and HSP70 genes. Out of 343 faecal samples tested, none were positive by microscopy and 55 were positive by PCR. Sequence analysis of SSU gene revealed the presence of Cryptosporidium muris (n = 4), C. andersoni (n = 3), C. ryanae (n = 1), C. occultus (n = 3), Cryptosporidium rat genotype I (n = 23), Cryptosporidium rat genotype IV (n = 16) and novel Cryptosporidium rat genotype V (n = 5). Spherical oocysts of Cryptosporidium rat genotype I obtained from naturally-infected rats, measuring 4.4-5.4 μm × 4.3-5.1 μm, were infectious to the laboratory rats, but not to the BALB/c mice (Mus musculus) nor Mongolian gerbils (Meriones unguiculatus). The prepatent period was 3 days post infection and the patent period was longer than 30 days. Naturally- and experimentally-infected rats showed no clinical signs of disease. Percentage of nucleotide similarities at the SSU, actin, HSP70 loci between C. ratti n. sp. and the rat derived C. occultus and Cryptosporidium rat genotype II, III, IV, and V ranged from 91.0 to 98.1%. These genetic variations were similar or greater than that observed between closely related species, i.e. C. parvum and C. erinacei (93.2-99.5%). Our morphological, genetic and biological data support the establishment of Cryptosporidium rat genotype I as a new species, Cryptosporidium ratti n. sp.

  • RESEARCH ARTICLE Cryptosporidium proliferans n. sp. (Apicomplexa: Cryptosporidiidae): Molecular and Biological Evidence of Cryptic Species within Gastric Cryptosporidium of Mammals
    2016
    Co-Authors: Martin Kváč, Lenka Hlaskova, Bohumil Sak, Jana Jezkova, Jiři Vitovec, Nikola Havrdova, Tereza Daňkova, Jiří K, Ynes Ortega, Lihua Xiao
    Abstract:

    The morphological, biological, and molecular characteristics of Cryptosporidiummuris strain TS03 are described, and the species name Cryptosporidium proliferans n. sp. is pro-posed. Cryptosporidium proliferans obtained from a naturally infected East African mole rat (Tachyoryctes splendens) in Kenya was propagated under laboratory conditions in rodents (SCID mice and southern multimammate mice,Mastomys coucha) and used in experiments to examine oocyst morphology and transmission. DNA from the propagated C. proliferans isolate, and C. proliferans DNA isolated from the feces of an African buffalo (Syncerus caf-fer) in Central African Republic, a donkey (Equus africanus) in Algeria, and a domestic horse (Equus caballus) in the Czech Republic were used for phylogenetic analyses. Oocysts of C. proliferans are morphologically distinguishable from C. parvum and C.muris HZ206, measuring 6.8–8.8 (mean = 7.7 μm) × 4.8–6.2 μm (mean = 5.3) with a length to width ratio of 1.48 (n = 100). Experimental studies using an isolate originated from T. splen

  • cryptosporidium tyzzeri n sp apicomplexa Cryptosporidiidae in domestic mice mus musculus
    Experimental Parasitology, 2012
    Co-Authors: Longxian Zhang, Changshen Ning, Fuchun Jian, Rongjun Wang, Chaochao Lv, Qiang Wang, Jinfeng Zhao, Michael J Arrowood, Lihua Xiao
    Abstract:

    Abstract The Cryptosporidium in the small intestine of domestic mice (Mus musculus) was initially described as Cryptosporidium parvum. Recent genetic and biologic characterization of Cryptosporidium isolates indicate that domestic mice are infected with several morphologically indistinguishable intestinal Cryptosporidium parasites with different host specificities, including C. parvum sensu stricto, mouse genotype I, and mouse genotype II. In this study, the morphological, biological, and genetic characteristics of the Cryptosporidium mouse genotype I are described. As a full re-description of C. parvum was made in 1985 for isolates from calves and humans and the name C. parvum has been widely used for the parasite that is infectious to both ruminants and humans, the mouse genotype I is named as Cryptosporidium tyzzeri. Oocysts of the new species (4.64 ± 0.05 μm × 4.19 ± 0.06 μm, with a mean shape index of 1.11 ± 0.02; n = 69) are slightly smaller than those of the re-described C. parvum. The prepatent period was six and seven days, and the patent period was 24–28 and 28–29 days in neonatal and adult mice, respectively. Oocysts were not infectious to lambs and calves. Light, transmission electron and scanning electron microscopy studies of the new species showed the presence of developmental stages in the microvillar brush border of the jejunum and ileum of experimentally infected mice, with the infection most intensive in the ileum. It had nucleotide sequences significantly different from C. parvum at the small subunit rRNA, 70 kDa heat shock protein, oocyst wall protein, actin, and the 60 kDa glycoprotein genes. Based on the morphological, genetic, and biological data and in compliance of established Cryptosporidium species naming criteria, this geographically widespread parasite is named as a new species in honor of Ernest Edward Tyzzer, who pioneered Cryptosporidium research.

  • Cryptosporidium fayeri n. sp. (Apicomplexa: Cryptosporidiidae) from the Red Kangaroo (Macropus rufus).
    The Journal of eukaryotic microbiology, 2008
    Co-Authors: Michelle L. Power, Una Ryan, Lihua Xiao
    Abstract:

    The morphology and infectivity of the oocysts of a new species of Cryptosporidium from the faeces of the red kangaroo (Macropus rufus) are described. Oocysts are structurally indistinguishable from those of Cryptosporidium parvum. Oocysts of the new species are passed fully sporulated, lack sporocysts, and measure 4.5-5.1 μm (mean=4.9) × 3.8-5.0 μm (mean=4.3 μm) with a length to width ratio 1.02:1.18 (mean 1.14) (n=50). Oocysts were not infectious for neonate ARC Swiss mice. Multi-locus analysis of numerous unlinked loci demonstrated this species to be distinct (90.64%-97.88% similarity) from C. parvum. Based on biological and molecular data, this Cryptosporidium infecting marsupials is proposed to be a new species Cryptosporidium fayeri n. sp.

  • cryptosporidium bovis n sp apicomplexa Cryptosporidiidae in cattle bos taurus
    Journal of Parasitology, 2005
    Co-Authors: Ronald Fayer, Monica Santin, Lihua Xiao
    Abstract:

    A new species of Cryptosporidium, C. bovis, is described. Oocysts of C. bovis, previously identified as Cryptosporidium genotype Bovine B (GenBank AY120911), are morphologically indistinguishable from those of C. parvum. They are excreted fully sporulated and contain 4 sporozoites, but lack sporocysts. Oocysts measure 4.76–5.35 μm (mean = 4.89 μm) × 4.17–4.76 μm (mean = 4.63 μm), with a length-to-width ratio of 1.06 (n = 50). Oocysts were not infectious for neonatal BALB/ c mice, but were infectious for 2 calves that were previously infected with C. parvum. Oocysts were not infectious for 2 experimentally exposed lambs less than 1 wk of age and were not detected in 42 lambs 2–3 mo of age, but were detected in a 2-wk-old lamb. In an earlier study, 79 of 840 calves on 14 dairy farms in 7 states were found infected with the new species. Most calves were 2–7 mo of age and none exhibited signs of diarrhea. This new species has been found in 10 of 162 calves aged 9 to 11 mo on a beef farm in Maryland. Fragments...

Dos Santos - One of the best experts on this subject based on the ideXlab platform.