Commercial small-scale chicken farms managed as all-in-all-out but operating with low standards of hygiene/biosecurity are increasingly common in Vietnam. These conditions facilitate the transmission of gastrointestinal helminths. However, there are no published data on helminths in these systems. We aimed (1) to determine the prevalence/burden of gastrointestinal helminths in small-scale commercial flocks in the Mekong Delta region and (2) to investigate the association between worm burdens and birds' weight and disease status. Randomly selected chickens (n = 120) from 'normal' flocks were investigated at the end of their production cycle (~ 18 weeks), as well as 90 chickens from 'diseased' flocks with signs of respiratory and/or severe disease. The gastrointestinal tract of chickens was dissected and all visible helminths were identified and counted. A total of 54.2% and 54.4% normal and diseased chickens contained helminths. Among colonised birds, the diseased ones harboured a higher mass of helminth worms than normal (healthy) birds (3.8 ± SD 8.6 g vs. 1.9 ± SD 6.3 g, respectively). Eight species were identified, including nematodes (Ascaridia galli, Cheilospirura hamulosa and Heterakis gallinarum), cestodes (Hymenolepis, Raillietina cesticillus, Raillietina echinobothrida, Raillietina tetragona,) and one trematode (Echinostomatidae). Heterakis gallinarum was the most prevalent helminth (43.3% and 42.2% in normal and sick chickens, respectively), followed by A. galli (26.7% and 41.1%). Colonised chickens weighed 101.5 g less than non-colonised birds. Colonisation was higher during the rainy months (May-November) for both H. gallinarum and A. galli. Anthelminthic usage was not associated with reduced helminth burdens. We recommend upgrading cleaning and disinfection and limiting access to ranging areas to control helminths in small-scale chicken flocks.
- MeSH
- anthelmintika terapeutické užití MeSH
- Cestoda klasifikace izolace a purifikace MeSH
- cizopasní červi klasifikace izolace a purifikace MeSH
- farmy MeSH
- gastrointestinální trakt parazitologie MeSH
- helmintózy zvířat farmakoterapie parazitologie MeSH
- hlístice klasifikace izolace a purifikace MeSH
- kur domácí MeSH
- nemoci drůbeže parazitologie MeSH
- prevalence MeSH
- tělesná hmotnost účinky léků MeSH
- Trematoda klasifikace izolace a purifikace MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Vietnam MeSH
Fecal samples from wild-caught common voles (n = 328) from 16 locations in the Czech Republic were screened for Cryptosporidium by microscopy and PCR/sequencing at loci coding small-subunit rRNA, Cryptosporidium oocyst wall protein, actin and 70 kDa heat shock protein. Cryptosporidium infections were detected in 74 voles (22.6%). Rates of infection did not differ between males and females nor between juveniles and adults. Phylogenetic analysis revealed the presence of eight Cryptosporidium species/genotypes including two new species, C. alticolis and C. microti. These species from wild-caught common voles were able to infect common and meadow voles under experimental conditions, with a prepatent period of 3-5 days post-infection (DPI), but they were not infectious for various other rodents or chickens. Meadow voles lost infection earlier than common voles (11-14 vs 13-16 DPI) and had significantly lower infection intensity. Cryptosporidium alticolis infects the anterior small intestine and has larger oocysts (5.4 × 4.9 µm), whereas C. microti infects the large intestine and has smaller oocysts (4.3 × 4.1 µm). None of the rodents developed clinical signs of infection. Genetic and biological data support the establishment of C. alticolis and C. microti as separate species of the genus Cryptosporidium.
- MeSH
- Arvicolinae parazitologie MeSH
- Cryptosporidium klasifikace genetika ultrastruktura MeSH
- feces parazitologie MeSH
- fluorescenční mikroskopie MeSH
- fylogeneze MeSH
- gastrointestinální trakt parazitologie patologie ultrastruktura MeSH
- genetická variace MeSH
- interferenční mikroskopie MeSH
- kryptosporidióza epidemiologie parazitologie přenos MeSH
- krysa rodu rattus MeSH
- kur domácí MeSH
- mikroskopie elektronová rastrovací MeSH
- Murinae MeSH
- myši inbrední BALB C MeSH
- myši inbrední C57BL MeSH
- myši MeSH
- nemoci hlodavců epidemiologie parazitologie přenos MeSH
- polymerázová řetězová reakce MeSH
- prevalence MeSH
- protozoální DNA chemie genetika izolace a purifikace MeSH
- RNA ribozomální genetika MeSH
- sekvence nukleotidů MeSH
- sekvenční seřazení veterinární MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- mužské pohlaví MeSH
- myši MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
- Geografické názvy
- Česká republika MeSH
Based on light and scanning electron microscopical studies of nematode specimens from the digestive tract of some rarely collected anguilliform and perciform fishes off New Caledonia, three new species of Cucullanus Müller, 1777 (Cucullanidae) are described: C. austropacificus n. sp. from the longfin African conger Conger cinereus (Congridae), C. gymnothoracis n. sp. from the lipspot moray Gymnothorax chilospilus (Muraenidae), and C. incognitus n. sp. from the seabream Dentex fourmanoiri (Sparidae). Cucullanus austropacificus n. sp. is characterized by the presence of cervical alae, ventral sucker, alate spicules 1.30-1.65 mm long, conspicuous outgrowths of the anterior and posterior cloacal lips and by elongate-oval eggs measuring 89-108 × 48-57 μm; C. gymnothoracis n. sp. is similar to the foregoing species, but differs from it in the absence of cervical alae and the posterior cloacal outgrowth, in the shape and size of the anterior cloacal outgrowth and somewhat shorter spicules 1.12 mm long; C. incognitus n. sp. (based on female morphology) differs from other congeneric species parasitic in the Sparidae mainly in possessing cervical alae, the postequatorial vulva, phasmids situated at the mid-length of the tail and in the size of the eggs (75-84 × 45-66 μm). A key to species of Cucullanus parasitizing anguilliform fishes is provided.
- MeSH
- Anguilliformes parazitologie MeSH
- gastrointestinální trakt parazitologie MeSH
- hlístice anatomie a histologie klasifikace genetika izolace a purifikace MeSH
- kloaka parazitologie MeSH
- mikroskopie elektronová rastrovací veterinární MeSH
- mikroskopie MeSH
- nematodózy epidemiologie parazitologie veterinární MeSH
- nemoci ryb epidemiologie parazitologie MeSH
- Perciformes parazitologie MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Nová Kaledonie MeSH
Microsporidia are a group of obligate intracellular eukaryotic parasites, which are able to infect a wide range of animals, including humans. Four genotypes of Encephalitozoon cuniculi have been found to date. The different courses of microsporidiosis described in humans, which are dependent on immunological status of the host and genotype of E. cuniculi, have been successfully imitated in murine models. In the present study, we quantified the microsporidial burden in individual organs of a murine experimental model, using qPCR and we compared the parasitic load of two genotypes of E. cuniculi, namely genotype II and III (EC II and EC III). While the extent of microsporidiosis caused by EC II gradually increased over 35 days post infection (DPI) in both immunocompetent and immunodeficient mice and caused death in the latter at 28 DPI, EC III had spread into all host organs by seven DPI and was not lethal for either mouse strain during the experimental time period. Moreover, EC III persisted in many organs until termination of the experiment. The number of microsporidial spores in individual organs was ten times higher in EC III-infected animals compared to those infected with EC II. EC II infection also progressively shifted towards organs outside the gastrointestinal tract (GIT) in both monitored mouse strains; whereas, EC III infection equally remained in both the GIT and organs outside the GIT. With the increasing use of molecular methods in diagnostics, it is important to better understand the pathophysiology of microsporidia, including its ability to escape from the immune system and persist in host organisms. Our results indicate that pathogenicity is not directly connected to spore burden, as infection caused by E. cuniculi genotype II is less extensive and spreads more slowly within the host organism than infection caused by E. cuniculi genotype III, but which caused the earlier death of immunodeficient mice.
- MeSH
- Arvicolinae MeSH
- Cercopithecus aethiops MeSH
- Encephalitozoon cuniculi klasifikace genetika růst a vývoj fyziologie MeSH
- encephalitozoonóza parazitologie MeSH
- gastrointestinální trakt parazitologie MeSH
- genotyp MeSH
- imunokompetence MeSH
- kvantitativní polymerázová řetězová reakce MeSH
- Microsporidia fyziologie MeSH
- modely nemocí na zvířatech MeSH
- myši inbrední BALB C MeSH
- myši SCID MeSH
- myši MeSH
- parazitární zátěž MeSH
- spory hub MeSH
- Vero buňky MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- srovnávací studie MeSH
The nematode genus Bulbocephalus Rasheed, 1966 (Nematoda, Physalopteridae) was found to be a homonym of Bulbocephalus Watson, 1916 (Apicomplexa) and, therefore, a new name, Rasheedia n. nom., is proposed to substitute it. Based on light and scanning electron microscope studies of specimens collected from the digestive tract of perciform fishes off New Caledonia, two new species of Rasheedia are described: R. heptacanthi n. sp. from the Cinnabar goatfish Parupeneus heptacanthus (Mullidae) (type host) and Dentex fourmanoiri (Sparidae), and R. novaecaledoniensis n. sp. from the Indian goatfish Parupeneus indicus (Mullidae). These new species are mainly characterized by the number of anterior protrusible oesophageal lobes (two in R. heptacanthi and four in R. novaecaledoniensis), structure of the oesophagus and the lengths of spicules. An amended diagnosis of Rasheedia and a key to species of this genus are provided. Three previously described congeneric species are transferred to Rasheedia as R. deblocki (Le-Van-Hoa, Pham-Ngoc-Khue & Nguyen-Thi-Lien, 1972) n. comb., R. inglisi (Rasheed, 1966) n. comb. and R. pseudupenei (Vassiliadès & Diaw, 1978) n. comb. Cestocephalus Rasheed, 1966 [genus inquirendum], including C. serratus Rasheed, 1966 and C. petterae (Le-Van-Hoa, Pham-Ngoc-Khue & Nguyen-Thi-Lien, 1972) n. comb., should be considered to be separate from Rasheedia. The names Pseudomazzia Bilqees, Ghazi & Haseeb, 2005 and P. macrolabiata Bilqees, Ghazi & Haseeb, 2005, established for a nematode somewhat resembling Rasheedia spp., should be considered nomina dubia. Rasheedia heptacanthi n. sp. and R. novaecaledoniensis n. sp. are the first representatives of the Physalopteridae recorded from fishes in New Caledonian waters.
- MeSH
- gastrointestinální trakt parazitologie MeSH
- hlístice anatomie a histologie klasifikace ultrastruktura MeSH
- nemoci ryb epidemiologie parazitologie MeSH
- Perciformes parazitologie MeSH
- slezina parazitologie MeSH
- vodní organismy MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Nová Kaledonie epidemiologie MeSH
BACKGROUND: Cysteine peptidases of clan CA, family C1 account for a major part of proteolytic activity in the haematophagous monogenean Eudiplozoon nipponicum. The full spectrum of cysteine cathepsins is, however, unknown and their particular biochemical properties, tissue localisation, and involvement in parasite-host relationships are yet to be explored. METHODS: Sequences of cathepsins L and B (EnCL and EnCB) were mined from E. nipponicum transcriptome and analysed bioinformatically. Genes encoding two EnCLs and one EnCB were cloned and recombinant proteins produced in vitro. The enzymes were purified by chromatography and their activity towards selected substrates was characterised. Antibodies and specific RNA probes were employed for localisation of the enzymes/transcripts in tissues of E. nipponicum adults. RESULTS: Transcriptomic analysis revealed a set of ten distinct transcripts that encode EnCLs. The enzymes are significantly variable in their active sites, specifically the S2 subsites responsible for interaction with substrates. Some of them display unusual structural features that resemble cathepsins B and S. Two recombinant EnCLs had different pH activity profiles against both synthetic and macromolecular substrates, and were able to hydrolyse blood proteins and collagen I. They were localised in the haematin cells of the worm's digestive tract and in gut lumen. The EnCB showed similarity with cathepsin B2 of Schistosoma mansoni. It displays molecular features typical of cathepsins B, including an occluding loop responsible for its exopeptidase activity. Although the EnCB hydrolysed haemoglobin in vitro, it was localised in the vitelline cells of the parasite and not the digestive tract. CONCLUSIONS: To our knowledge, this study represents the first complex bioinformatic and biochemical characterisation of cysteine peptidases in a monogenean. Eudiplozoon nipponicum adults express a variety of CLs, which are the most abundant peptidases in the worms. The properties and localisation of the two heterologously expressed EnCLs indicate a central role in the (partially extracellular?) digestion of host blood proteins. High variability of substrate-binding sites in the set of EnCLs suggests specific adaptation to a range of biological processes that require proteolysis. Surprisingly, a single cathepsin B is expressed by the parasite and it is not involved in digestion, but probably in vitellogenesis.
- MeSH
- gastrointestinální trakt parazitologie MeSH
- hydrolýza MeSH
- interakce hostitele a parazita MeSH
- kapři parazitologie MeSH
- kathepsin B chemie genetika izolace a purifikace metabolismus MeSH
- kathepsin L chemie genetika izolace a purifikace metabolismus MeSH
- proteolýza MeSH
- rekombinantní proteiny analýza genetika izolace a purifikace MeSH
- stanovení celkové genové exprese MeSH
- Trematoda enzymologie genetika MeSH
- zavlečené druhy MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
BACKGROUND: Leishmania development in sand flies is confined to the alimentary tract and is closely connected with blood meal digestion. Previously, it has been published that activities of sand fly midgut proteases are harmful to Leishmania, especially to amastigote-promastigote transition forms. However, our experiments with various Leishmania-sand fly pairs gave quite opposite results. METHODS: We evaluated the effect of semi-digested midgut content on different life stages of Leishmania donovani and Leishmania major in vitro. Various morphological forms of parasites, including macrophage-derived amastigotes and transition forms, were incubated 2 h with midguts dissected at various intervals (6-72 h) post-blood meal or with commercially available proteinase, and their viability was determined using flow cytometry. In parallel, using amastigote-initiated experimental infections, we compared development of L. donovani in sand flies that are either susceptible (Phlebotomus argentipes and P. orientalis) or refractory (P. papatasi and Sergentomyia schwetzi) to this parasite. RESULTS: In vitro, sand fly midgut homogenates affected L. major and L. donovani in a similar way; in all sand fly species, the most significant mortality effect was observed by the end of the blood meal digestion process. Surprisingly, the most susceptible Leishmania stages were promastigotes, while mortality of transforming parasites and amastigotes was significantly lower. Parasites were also susceptible to killing by rabbit blood in combination with proteinase, but resistant to proteinase itself. In vivo, L. donovani developed late-stage infections in both natural vectors; in P. argentipes the development was much faster than in P. orientalis. On the other hand, in refractory species P. papatasi and S. schwetzi, promastigotes survived activity of digestive enzymes but were lost during defecation. CONCLUSIONS: We demonstrated that Leishmania transition forms are more resistant to the killing effect of semi-digested blood meal than 24 h-old promastigotes. Data suggest that Leishmania mortality is not caused directly by sand fly proteases, we assume that this mortality results from toxic products of blood meal digestion. Survival of L. donovani promastigotes in refractory sand flies until blood meal defecation, together with similar mortality of Leishmania parasites incubated in vitro with midgut homogenates of susceptible as well as refractory species, contradict the previously raised hypotheses about the role of midgut proteases in sand fly vector competence to Leishmania.
- MeSH
- gastrointestinální trakt enzymologie parazitologie MeSH
- králíci MeSH
- krev metabolismus MeSH
- Leishmania donovani fyziologie MeSH
- Leishmania major fyziologie MeSH
- Phlebotomus parazitologie MeSH
- proteasy metabolismus MeSH
- viabilita buněk MeSH
- zvířata MeSH
- Check Tag
- králíci MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
BACKGROUND: Although avian trypanosomes are widespread parasites, the knowledge of their vectors is still incomplete. Despite biting midges (Diptera: Ceratopogonidae) are considered as potential vectors of avian trypanosomes, their role in transmission has not been satisfactorily elucidated. Our aim was to clarify the potential of biting midges to sustain the development of avian trypanosomes by testing their susceptibility to different strains of avian trypanosomes experimentally. Moreover, we screened biting midges for natural infections in the wild. RESULTS: Laboratory-bred biting midges Culicoides nubeculosus were highly susceptible to trypanosomes from the Trypanosoma bennetti and T. avium clades. Infection rates reached 100%, heavy infections developed in 55-87% of blood-fed females. Parasite stages from the insect gut were infective for birds. Moreover, midges could be infected after feeding on a trypanosome-positive bird. Avian trypanosomes can thus complete their cycle in birds and biting midges. Furthermore, we succeeded to find infected blood meal-free biting midges in the wild. CONCLUSIONS: Biting midges are probable vectors of avian trypanosomes belonging to T. bennetti group. Midges are highly susceptible to artificial infections, can be infected after feeding on birds, and T. bennetti-infected biting midges (Culicoides spp.) have been found in nature. Moreover, midges can be used as model hosts producing metacyclic avian trypanosome stages infective for avian hosts.
- MeSH
- Ceratopogonidae anatomie a histologie parazitologie MeSH
- gastrointestinální trakt parazitologie MeSH
- hmyz - vektory parazitologie MeSH
- hostitelská specificita MeSH
- kanáři parazitologie MeSH
- mikroskopie elektronová rastrovací MeSH
- nemoci ptáků parazitologie přenos MeSH
- polymerázová řetězová reakce MeSH
- ptáci parazitologie MeSH
- Trypanosoma klasifikace genetika fyziologie ultrastruktura MeSH
- trypanozomiáza diagnóza parazitologie přenos veterinární MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
BACKGROUND: Infection caused by parasites from L. donovani complex can manifest as a serious visceral disease or a self-healing milder cutaneous form. The different tropism and pathology in humans is caused by the interaction between parasites, host and vector determinants but the mechanisms are not well understood. In Cukurova region in Turkey we previously identified a major focus of cutaneous leishmaniasis caused by L. donovani/infantum hybrids (CUK strain) and isolated this parasite from the locally abundant sand fly, Phlebotomus tobbi. Here, we present the first experimental study with P. tobbi. We tested the susceptibility of this species to various Leishmania under laboratory conditions, characterized glycoproteins in the P. tobbi midgut putatively involved in parasite-vector interaction and compared the development of the CUK strain in the sand fly with one other dermotropic and three viscerotropic strains belonging to the L. donovani complex. METHODS: Females of laboratory reared P. tobbi, P. perniciosus and Lutzomyia longipalpis were infected using membrane feeding on rabbit blood containing promastigotes of various Leishmania species with different tropisms. The individual guts were checked microscopically for presence and localization of Leishmania parasites; the number of parasites was assessed more precisely by qPCR. In addition, glycosylation of midgut proteins of P. tobbi was studied by lectin blotting of midgut lysate with lectins specific for terminal sugars of N-type and O-type glycans. RESULTS: High infection rates, heavy parasite loads and late-stage infection with colonization of the stomodeal valve were observed in P. tobbi infected by Leishmania major or L. infantum CUK hybrid. In parallel, lectin blotting revealed the presence of O-glycosylated proteins in the P. tobbi midgut. In P. perniciosus and L. longipalpis all five Leishmania strains tested developed well. In both vectors, significantly higher parasite numbers were detected by qPCR for dermotropic L. donovani from Cyprus, however, in all other parameters studied, including localization of infection and colonization of stomodeal valve, dermotropic and viscerotropic strains were not significantly different. CONCLUSIONS: We showed high susceptibility of P. tobbi to various Leishmania spp. This, together with the presence of O-glycosylated midgut proteins in their midguts demonstrate that P. tobbi is a permissive vector. Two dermotropic and three viscerotropic strains from the L. donovani complex developed late-stage infections in natural L. infantum vectors, P. perniciosus and L. longipalpis and none of the parameters studied seem to be linked with different tropism of parasites in the vertebrate host.
- MeSH
- gastrointestinální trakt parazitologie MeSH
- hmyz - vektory parazitologie MeSH
- králíci MeSH
- Leishmania infantum genetika růst a vývoj izolace a purifikace MeSH
- Leishmania major genetika růst a vývoj izolace a purifikace MeSH
- leishmanióza kožní epidemiologie parazitologie MeSH
- lidé MeSH
- Phlebotomus parazitologie MeSH
- Psychodidae parazitologie MeSH
- tropismus MeSH
- zvířata MeSH
- Check Tag
- králíci MeSH
- lidé MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- srovnávací studie MeSH
- Geografické názvy
- Turecko MeSH
