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1.
ABSTRACT Goussia girellae n. sp. is described from the opaleye fish, Girella nigricans. Merogonic stages were observed in the apices of intestinal epithelial cells, in the lamina propria, and in extra-intestinal sites including liver, gills, and spleen. Gamonts were observed in the intestinal epithelial cells. Only unsporulated oocysts were detected in the intestine, and sporulation occurred when feces containing oocysts were incubated for 48 h in seawater at 21°C. Oocysts are elongated (24.8 × 14.7 μm) with a wall about 200 nm thick and have no residuum, micropyle, or polar granule. Sporocysts are ellipsoid (8.5 × 4.5 μm), have a thin two-layered wall approximately 30 nm thick, and consist of two valves joined by a suture. Although moribund opaleye were also infected with Gyrodactylus sp., Cryptobia sp., Cardicola sp., and epitheliocystis organisms (chlamydia), all fish were heavily infected with G. girellae and morbidity was thus attributed to the coccidium.  相似文献   

2.
Oöcysts of Goussia chalupskyi n. sp. are described from the faeces of the chub Leuciscus cephalus (Cyprinidae) from Southern Bohemia, Czech Republic. The oöcysts are spherical, 11.0 (10.5–11.5) m in diameter. The sporocysts are broadly oval to subspherical, 7.7 (7.0–8.5) × 5.7 (5.0–6.5) m, with a sporocyst residuum composed of 2–4 granules. Merogonial and gamogonial stages were found in the posterior part of the intestine.  相似文献   

3.
Jirků M  Modrý D  Slapeta JR  Koudela B  Lukes J 《Protist》2002,153(4):379-390
The phylogenetic relationships of Goussia janae and Choleoeimeria sp. were analyzed using the small subunit ribosomal RNA gene (SSU rDNA). This is a first attempt to study the molecular phylogeny of coccidian genera parasitizing strictly poikilotherm hosts. The biliary Eimeria-like coccidia of reptiles classified into the genus Choleoeimeria form a sister clade to the family Eimeriidae, which confirms the separate generic status of the genus Choleoeimeria. The position of Goussia is less robustly resolved, since it forms a trichotomy with the Eimeriidae and Sarcocystidae, or alternatively constitutes the earliest branch of the coccidian lineage. Morphological similarities, namely the extracytoplasmic location of the endogenous stages, and the presence of sutures in the sporocyst wall are discussed in the context of the traditional classification of eimeriids. In contrast to the morphology-based systematics, the monophyly of Goussia and Choleoeimeria is not supported by the SSU rDNA data.  相似文献   

4.
ABSTRACT Life cycle stages of Goussia pannonica from naturally-infected white bream Blicca bjoerkna were studied by light and electron microscopy. Fourteen of the sixteen fish examined were infected, with developmental stages found in all parts of the intestine. Merogonial, gamogonial, and sporogonial stages were localized intracellularly and extracytoplasmically in the microvillous region of enterocytes. They were separated from the gut lumen by closely apposed enterocyte and parasitophorous vacuole membranes. There were two types of extracytoplasmic attachment: 1) monopodial, with a single zone of attachment, and 2) spider-like, with several isolated zones of attachment to the host cell. First-generation merozoites were formed by ectomerogony. Second- or third-generation merozoites were formed by endodyogeny and endopolygeny. Thirty to 50 biflagellated microgametes developed at the periphery of a microgamont. Macrogamonts contained lipid inclusions, amylopectin and dense granules; however, granules comparable to wall-forming bodies type I and II were absent. At the beginning of sporogony, the sporont cytoplasm detached from two layers which subsequently became constituents of the oocyst wall. After the rupture of enterocyte and parasitophorous vacuole membranes, the sporont was released into the water where exogenous sporulation was completed within 48 h. The thin sporocyst wall contained a small longitudinal suture. Sporocyst and oocyts walls were of similar structure.  相似文献   

5.
In the examination of 90 Chondrostoma polylepis caught in the Esla River, a coccidium of the genus Goussia was found in the swimbladder, peritoneum, kidney, and ureter. It is described as Goussia polylepidis n. sp. and its taxonomic affinities are discussed. Data on its prevalence and seasonality are also given.  相似文献   

6.
Seventy-seven specimens of seven freshwater fish species harvested in four sites from rivers and ponds of the Gauteng, North West and Limpopo Provinces (South Africa) were surveyed for coccidian infections. Two fish species were infected with apicomplexans belonging to Goussia Labbé, 1896. In banded tilapia Tilapia sparrmanii Smith unsporulated oöcysts of G. vanasi (Landsberg &; Paperna, 1987) were found which became sporulated in tap-water within 24 hours. Another species in the gut of chubbyhead barb Barbus anoplus Weber harboured sporulated oöcysts in the faeces and in the intestinal epithelium. The latter species has been described as G. anopli n. sp.  相似文献   

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9.
Cryptosporidiosis is a common parasitic infection in birds that is caused by more than 25 Cryptosporidium species and genotypes. Many of the genotypes that cause avian cryptosporidiosis are poorly characterized. The genetic and biological characteristics of avian genotype III are described here and these data support the establishment of a new species, Cryptosporidium proventriculi. Faecal samples from the orders Passeriformes and Psittaciformes were screened for the presence of Cryptosporidium by microscopy and sequencing, and infections were detected in 10 of 98 Passeriformes and in 27 of 402 Psittaciformes. Cryptosporidium baileyi was detected in both orders. Cryptosporidium galli and avian genotype I were found in Passeriformes, and C. avium and C. proventriculi were found in Psittaciformes. Cryptosporidium proventriculi was infectious for cockatiels under experimental conditions, with a prepatent period of six days post-infection (DPI), but not for budgerigars, chickens or SCID mice. Experimentally infected cockatiels shed oocysts more than 30 DPI, with an infection intensity ranging from 4,000 to 60,000 oocysts per gram (OPG). Naturally infected cockatiels shed oocysts with an infection intensity ranging from 2,000 to 30,000 OPG. Cryptosporidium proventriculi infects the proventriculus and ventriculus, and oocysts measure 7.4 × 5.8 μm. None of the birds infected C. proventriculi developed clinical signs.  相似文献   

10.
Goussia lusca n. sp. is described from the liver of pouting Trisopterus luscus from the NE Atlantic Ocean in Ibero-Atlantic Portuguese and Spanish waters. Mature oocysts were 31.7 (28.8 to 35.4) microm in diameter. Each oocyst contained 4 ellipsoidal sporocysts arranged in an aleatory position, and measuring approximately 13.7 x 9.2 microm. Each sporocyst contained 2 sporozoites. Ultrastructurally, the sporocyst wall consisted of a dense inner layer 115 nm thick, transversely striated, regularly intercalated by thin grooves with electron-lucent spaces, and separated from the outer layer by a thin, light (electron-lucent) space. The outer layer was multilamellated and consisted of parallel dense bands alternating with light spaces. These lamellae formed filamentous extensions of the wall. The dehiscence suture, a characteristic feature of the genus, was present in the sporocysts. No external clinical signs were observed in the host fish. Parasites observed in the liver tissue were often enveloped in a yellowish-brown matrix, generally known as 'yellow bodies'. Sometimes sporocysts were observed in direct contact with the liver cells. Parasites in degeneration and aggregations of amylopectin granules were frequently observed surrounded by host inflammatory cells. In severe infections, we observed large agglomerations of oocysts encapsulated by layers of concentrically arranged connective tissue forming large granulomas, which caused significant replacement of the host liver parenchyma by the parasite.  相似文献   

11.
Pholeohedra overstreeti n. g., n. sp. (Digenea: Haploporidae) is described from Girella zebra (Kyphosidae) in South Australia. The new genus is compared with all genera of Haploporidae sensu lato (including Atractotrematidae, Megasolenidae and Waretrematidae) and has a unique bell-shaped concavity at its posterior end. The genus otherwise resembles Hapladena in the arrangement of the testis, vitellarium and gut but also resembles Megasolena, Metamegasolena and Vitellibaculum except in having a single testis. This is the first haploporid reported from kyphosid fishes in Australia.  相似文献   

12.
Molecular and biological characteristics of a new species of Cryptosporidium from the feces of pigs (Sus scrofa) is described. Oocysts are structurally indistinguishable from those of Cryptosporidium parvum; they are passed fully sporulated, lack sporocysts, and measure 4.9-4.4 microm (mean = 4.6 microm) x 4.0-4.3 microm (mean = 4.2 microm); length to width ratio 1.1 (n = 50). Cryptosporidium suis is not transmissible to nude mice and is poorly infectious for cattle. Molecular and phylogenetic analyses at the 18S ribosomal RNA, heat shock protein 70, and actin gene loci demonstrate C. suis to be genetically distinct from all known species and genotypes of Cryptosporidium, and thus is named as Cryptosporidium suis.  相似文献   

13.
Faecal samples from striped field mice (n = 72) and yellow-necked mice (n = 246) were screened for Cryptosporidium by microscopy and PCR/sequencing. Phylogenetic analysis of small-subunit rRNA, Cryptosporidium oocyst wall protein and actin gene sequences revealed the presence of C. parvum, C. hominis, C. muris and two new species, C. apodemi and C. ditrichi. Oocysts of C. apodemi are smaller than C. ditrichi and both are experimentally infectious for yellow-necked mice but not for common voles. Additionally, infection by C. ditrichi was established in one of three BALB/c mice. The prepatent period was 7–9 and 5–6 days post infection for C. apodemi and C. ditrichi, respectively. The patent period was greater than 30 days for both species. Infection intensity of C. ditrichi ranged from 4000–50,000 oocyst per gram of faeces and developmental stages of C. ditrichi were detected in the jejunum and ileum. In contrast, neither oocysts nor endogenous developmental stages of C. apodemi were detected in faecal or tissue samples, although C. apodemi DNA was detected in contents from the small and large intestine. Morphological, genetic, and biological data support the establishment of C. apodemi and C. ditrichi as a separate species of the genus Cryptosporidium.  相似文献   

14.
15.
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 microm (mean = 4.89 microm) x 4.17-4.76 microm (mean = 4.63 microm), 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 of the 18S rDNA, HSP-70, and actin genes were amplified by PCR, and purified PCR products were sequenced. Multilocus analysis of the 3 unlinked loci demonstrated the new species to be distinct from C. parvum and also demonstrated a lack of recombination, providing further evidence of species status. Based on these biological and molecular data, we consider this highly prevalent Cryptosporidium that infects primarily postweaned calves to be a new species and propose the name Cryptosporidium bovis n. sp. for this parasite.  相似文献   

16.
A new species of Cryptosporidium is described from the feces of domestic cattle, Bos taurus. Oocysts are structurally similar to those of Cryptosporidium muris described from mice but are larger than those of Cryptosporidium parvum. Oocysts of the new species are ellipsoidal, lack sporocysts, and measure 7.4 x 5.5 microm (range, 6.0-8.1 by 5.0-6.5 microm). The length to width ratio is 1.35 (range, 1.07-1.50). The colorless oocyst wall is < 1 microm thick, lacks a micropyle, and possesses a longitudinal suture at one pole. A polar granule is absent, whereas an oocyst residuum is present. Oocysts were passed fully sporulated and are not infectious to outbred, inbred immunocompetent or immunodeficient mice, chickens or goats. Recent molecular analyses of the rDNA 18S and ITS1 regions and heat-shock protein 70 (HSP-70) genes demonstrate this species to be distinct from C. muris infecting rodents. Based on transmission studies and molecular data, we consider the large form of Cryptosporidium infecting the abomasum of cattle to be a new species and have proposed the name Cryptosporidium andersoni n. sp. for this parasite.  相似文献   

17.
The structure and infectivity of the oocysts of a new species of Cryptosporidium from the feces of humans are described. Oocysts are structurally indistinguishable from those of Cryptosporidium parvum. Oocysts of the new species are passed fully sporulated, lack sporocysts. and measure 4.4-5.4 microm (mean = 4.86) x 4.4-5.9 microm (mean = 5.2 microm) with a length to width ratio 1.0-1.09 (mean 1.07) (n = 100). Oocysts were not infectious for ARC Swiss mice, nude mice. Wistar rat pups, puppies, kittens or calves, but were infectious to neonatal gnotobiotic pigs. Pathogenicity studies in the gnotobiotic pig model revealed significant differences in parasite-associated lesion distribution (P = 0.005 to P = 0.02) and intensity of infection (P = 0.04) between C. parvum and this newly described species from humans. In vitro cultivation studies have also revealed growth differences between the two species. Multi-locus analysis of numerous unlinked loci, including a preliminary sequence scan of the entire genome demonstrated this species to be distinct from C. parvum and also demonstrated a lack of recombination, providing further support for its species status. Based on biological and molecular data, this Cryptosporidium infecting the intestine of humans is proposed to be a new species Cryptosporidium hominis n. sp.  相似文献   

18.
The Javan ferret-badger Melogale orientalis (Carnivora: Mustelidae: Helictidinae) is a small carnivore endemic to Indonesia. In the family Mustelidae, 10 Eimeria, 12 Cystoisopora, one Isospora, and one Hammondia species are known, but no eimeriid coccidia has been yet described in the subfamily Helictinidae (ferret badgers). Coproscopic examination of Javan ferret-badgers imported into the Czech Republic revealed the presence of coccidian oocysts. Sporulated oocysts differ from other Eimeria known in the family Mustelidae by their small size (12.4–16.1 × 10.4–13.4 μm) and ovoidal shape. Morphological data and phylogenetic analyses of 18S rRNA and COI genes indicated a new species of Eimeria found in faecal samples of Javan ferret badgers. The species is described as E. melogale n. sp.  相似文献   

19.
ABSTRACT. The morphology and genetic characterisation of a new species of piroplasm identified in the blood of the Gilbert's potoroo ( Potorous gilbertii ) from the Two Peoples Bay Nature Reserve near Albany, Western Australia, is described from blood and tissue samples from 16 Gilbert's potoroos. Microscopy of blood showed these parasites are highly pleomorphic with a mean length of 1.8 μm and mean width of 0.85 μm. Phylogenetic analysis of 18S rRNA sequence data identified the piroplasm as a new species of Theileria that is closely related to other Australian marsupial piroplasm species. Based on biological and molecular data, it is proposed that the parasite from Gilbert's potoroo be given the name Theileria gilberti n. sp.  相似文献   

20.
SYNOPSIS. The blood of each of 95 turtles (8 species) collected from southeastern Louisiana was infected with some or all of the merogonic stages and gametocyte stage of Haemogregarina pseudemydis n. sp. Five species of turtles harbored Pirhemocyton chelonarum n. sp. Turtle Haemogregarina and Pirhemocyton are locality records for Louisiana. Pirhemocyton is reported for the first time in turtles and in the continental U.S.A.  相似文献   

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