首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 46 毫秒
1.
A new coccidian parasite of the genus Eimeria Schneider, 1875 is described from the subterranean African silvery mole-rat Heliophobius argenteocinereus Peters, 1846. Oocysts of Eimeria burdai sp. n. were subspherical to broadly ellipsoidal 17.8 (16-19) x 14.1 (12-15), with a shape index 1.2 (1.1-1.4). Oocyst wall was bilayered, smooth and colourless, approximately 1.0 thick. Outer layer was significantly thicker than inner one. A micropyle and oocyst residuum were absent. One or two ellipsoidal or spherical polar granules were present. Sporocysts were ellipsoidal, 10.8 (9-12) x 6.2 (5-8) with a shape index 1.7 (1.5-1.9). Sporocyst wall was single-layered, thin, smooth and colourless, with small Stieda body at the pointed end. In freshly sporulated oocysts, spherical sporocyst residuum was composed of small granules enclosed by a thin membrane. Sporozoites were elongate, lying length-wise in the long axis of the sporocyst, partially curled around each other, with single large refractile body located posteriorly. Faintly distinguishable nucleus was in the central part of the sporozoite. This eimerian represents the first coccidian species described from subterranean African silvery mole-rat (Rodentia: Bathyergidae).  相似文献   

2.
Parasitological examination of faeces of 26 snakes kept in Bio-Ken Snake Farm, Watamu, Kenya revealed new species of Eimeria Schneider, 1875 in Telescopus semiannulatus Smith, 1849. Oocysts of Eimeria arabukosokokensis sp. n. are cylindrical 26.8 (25-29) x 15.1 (14-16) microm with smooth, bilayered oocyst wall and a single polar granule. The broadly ellipsoidal sporocysts average 9.3 (8.5-10) x 7.1 (6.5-7.5) microm and possess single-layered wall composed of two plates joined by longitudinal suture. Caryospora cf. regentensis Daszak et Ball, 2001 is reported from Dendroaspis angusticeps (Smith, 1849) and two additional forms of Caryospora Léger, 1904 are reported and morphologically characterised from a single specimen of Psammophis orientalis Broadley, 1977. Systematic status of Caryospora spp. in sub-Saharan Psammophis Boie, 1827 is discusses and all species reported by various authors to date are suggested to be treated as species inquirendae until more detailed data on these parasites and their hosts are available.  相似文献   

3.
Two new species of coccidian parasites are described from African reptiles. Oocysts of Eimeria foulshami sp. n. from the plated lizard Gerrhosaurus major bottegoi Del Prato of Sudan are ellipsoidal, 24.1 x 14.9 (23-26.5 x 14-17.8) microm with a bilayered, colourless oocyst wall and lack polar granules. The ellipsoidal sporocysts average 8.6 x 4.6 (7-10.6 x 4.4-7) microm and possess a prominent, globular, sporocyst residuum. Oocysts of Caryospora regentensis sp. n. from the Eastern green mamba Dendroaspis augusticeps Smith, 1849 [corrected] of Kenya are spherical to subspherical, 16.8 x 16.4 (16-17.6 x 15-17.2) microm with a bilayered oocyst wall and a single polar granule. The ellipsoidal sporocysts average 13.0 x 10.3 (10.2-14 x 9.2-11) microm and possess a Stieda and substieda body and a prominent globular sporocyst residuum. Oocysts of Caryospora legeri Hoare, 1933 are reported from a hissing sand snake, Psammophis sibilans sibilans L. from Nigeria, representing a new geographical record. The oocysts are slightly larger than the type, but otherwise identical. Caryospora psammophi Bray, 1960 and C. hermae Bray, 1960 from Psammophis sibilans phillipsi, oocysts of which are morphologically similar to and overlap in dimensions with C. legeri Hoare, 1933, are synonymised with the latter species. Eimeria samiae Iskander et Tadros, 1979 is emended to E. samyadeli to reflect the gender of the person the species was named after and because E. sani is preoccupied. In addition to these findings, Eimeria bohemi Modry, Slapeta et Koudela, 2000 and oocysts of an unidentified spherical Eimieria sp. are reported from Chamaeleo dilepis dilepis Leach from Cameroon.  相似文献   

4.
Coprological examination of 71 samples from a breeding colony of veiled chameleons, Chamaeleo calyptratus Duméril et Duméril, 1851, revealed a presence of two species of coccidia. In 100% of the samples examined, oocysts of Isospora jaracimrmani Modry et Koudela, 1995 were detected. A new coccidian species, Choleoeimeria hirbayah sp. n., was discovered in 32.4% of samples from the colony. Its oocysts are tetrasporocystic, cylindrical, 28.3 (25-30) x 14.8 (13.5-17.5) microm, with smooth, bilayered, -1 microm thick wall. Sporocysts are dizoic, ovoidal to ellipsoidal, 10.1 (9-11) x 6.9 (6-7.5) microm, sporocyst wall is composed of two plates joined by a meridional suture. Endogenous development is confined to the epithelium of the gall bladder, with infected cells being typically displaced from the epithelium layer towards lumen. A taxonomic revision of tetrasporocystic coccidia in the Chamaeleonidae is provided.  相似文献   

5.
Parasitological examination of two ornate Nile monitors Varanus ornatus (Daudin, 1803) imported from Benin revealed the presence of a new species of Caryospora. Oocysts of Caryospora varaniornati sp. n. are spherical to slightly subspherical, 12.0 (11-12.5) x 11.5 (11-12) microm, without amicropyle and oocyst residuum, and occasionally possessing one small polar granule. Sporocysts are broadly ellipsoidal, 8.8 (8.5-9.5) x 6.7 (6.5-7) microm; a lentil-like Stieda body is present, ca. 0.5 x 1 microm; substieda body not visible. Experimental infection of a closely related host, Varanus niloticus (L.), did not lead to the oocyst excretion despite the fact that one of the experimentally inoculated monitors was immunosuppressed by dexamethasone. Histological examination did not reveal stages of coccidian development. Therefore, it is possible that C. varaniornati is strictly host specific.  相似文献   

6.
Eimeria dorcadis Mantovani, 1966 is redescribed from dorcas gazelle (Gazella dorcas (L.)) from Saudi Arabia. Oocysts were detected in 7 out of 22 faecal samples (32%) using floatation method. The sporulated oocysts are cylindrical, slightly flattened at the micropylar pole, measure in average 32 x 19 microm (27-36 x 16-24 microm), length/width ratio being 1.7 (1.5-2.1). Oocyst wall is 1.2 microm thick, smooth, double-layered; outer layer is slightly thicker, light blue in colour; inner layer brownish, with micropyle in the inner layer and apparently continual outer one, measures 2.2 microm, but lacks a micropylar cap. The sporocyst elongate-ellipsoidal, measures 14 x 8 microm (12-17 x 6-9 microm), length/width ratio being 1.8, with sporocyst residuum as circular compact, coarse, refractile granules. Stieda body is present, while substieda body is absent. Sporozoites banana-shaped, measure 11 x 2.5 microm, each with a large spheroidal refractile body at the wider pole. Sporulation time is 2-3 days at 25 +/- 2 degrees C.  相似文献   

7.
A new Microsporidium sp. infects Rhizophagus grandis Gyllenhall, a beetle which preys on the bark beetle Dendroctonus micans Kugellan in Turkey. Mature spores are single, uninucleate, oval in shape (3.75 +/- 0.27 microm in length by 2.47 +/- 0.13 microm in width), with a subapically fixed polar filament. The polar filament is anisofilar, coiled in 7-8 normal and 3-4 reduced coils. Other characteristic features of the microsporidium are the four/five nuclear divisions to form 16/32 (commonly 16) spores, subpersistent sporophorous vesicles (pansporoblasts) remaining till formation of the endospore, and the vesicles dissolved with free mature spores. The polaroplast is divided into three zones: an amorphous zone, dense layers, and a lamellartubular area extending to the central part of the spore.  相似文献   

8.
A new species of trichosomoidid nematode, Huffmanela paronai sp. n., is established on the basis of its egg morphology and biological characters. The dark-shelled, embryonated eggs of this histozoic parasite occur in masses in the epidermis of the swordfish Xiphias gladius L. (Xiphiidae, Perciformes) from the Ligurian Sea in northern Italy. The eggs are concentrated in groups appearing as black spots in the skin of the fish host, being distributed mainly on the lower part of its body (lower jaw, gill covers, pectoral, anal and caudal fins, lower half of body). The parasite's eggs are characterised mainly by their shape and markedly small size (48-51 x 21-24 microm), an aspinose surface, relatively small polar plugs, and thick egg wall (3 microm). This is the first Huffmanela species reported from fish in Europe.  相似文献   

9.
Coprological examination of New Caledonian geckoes of the genus Rhacodactylus Fitzinger, 1843 revealed two new species of coccidia. Isospora leachiani sp. n. from R. leachianus (Cuvier, 1829) has oval, colourless oocysts, measuring 21-26 x 16-18.5 microm. Sporocysts are ellipsoidal, 11-12.5 x 6.5-8 microm, with distinct Stieda and substieda bodies. Oocysts of Isospora sykorai sp. n. from R. ciliatus (Guichenot, 1866) are elongately oval to cylindrical, 20-23.5 x 11-14 microm; sporocysts of this species are ellipsoidal, 10-11.5 x 7-8 microm, with a slightly pointed end and Stieda and substieda bodies. Infected geckoes did not exhibit any alteration of their health status.  相似文献   

10.
Isospora carliae sp. n. is described from the blue-throated rainbow skink Carlia rhomboidalis (Peters), from Daintree Forest, North Queensland, Australia. Oocysts are ellipsoidal, 16.8-21.0 x 12.6-15.4 microm in size, with their two sporocysts, 9.0-14.0 x 7.0-9.24 microm in size, positioned along the wide axis. Sporozoites contain a distinct refractile body and are accompanied by a residuum. All endogenous development occurs within the host-cell nucleus. Nuclei are sometimes invaded by several merozoites, but only infections by a single parasite persist. Nuclei lodging meronts, mature microgamonts and premature macrogamonts have an elongate shape. Some meronts exhibit a membrane-bound cytoplasmic inclusion that contains many micronemes.  相似文献   

11.
Myxobolus porofilus sp. n. is described infecting the visceral cavity of Prochilodus lineatus (Valenciennes, 1836) cultivated in S?o Paulo State, Brazil. The plasmodial form of the parasite is 3-5 mm in length and appeared compressed between the wall of the visceral cavity and the pyloric caecum, reposing on this organ. The spores are small (length 5.7 +/- 0.3 microm, width 4.8 +/- 0.2 microm; mean +/- SD) and round to elliptical in frontal view. The valve surfaces are smooth and have sutural folds. The polar capsules are ovoid, small (length 1.6 +/- 0.1 microm, width 1.1 +/- 0.1 microm) and equal in size. The polar filaments have three turns aligned perpendicularly to the longitudinal axis of the capsule. A conspicuous polar filament pore is arranged at the anterior end of the spore. The only reaction observed upon histological analysis was the presence of a capsule of connective tissue surrounding the plasmodia. This is the first report of a myxosporean parasite in the Prochilodontidae.  相似文献   

12.
Microsporidia are a group of obligate intracellular unicellular eukaryotes that can parasitize a wide variety of other eukaryotes ranging from protists to invertebrates and vertebrates. In this study, we examined the microsporidium Nosema sp. isolated from the mulberry pest, Hemerophila atrilineata Butler, 1881, named herein "Nosema sp. HA". The fresh spores were long oval in shape, 3.8 +/- 0.4 microm in length and 1.9 +/- 0.3 microm in width. Analysis of tissue infection of silkworm, Bombyx mori Linnaeus, 1758, indicated that the midgut, Malpighian tubules, muscle, fat body, silk glands, hemocytes, nerve tissue and gonads of silkworm were infected with Nosema sp. HA. The complete rRNA gene sequence of this microsporidium contained 4 305 base pairs (GenBank Accession JN882299), including the large subunit rRNA (2492 bp), the internal transcribed spacer (187 bp), the small subunit rRNA (1232 bp), the intergenic spacer (279 bp) and the 5S region (115 bp). The organization of the rRNA gene is 5'-LSU-ITS-SSU-IGS-5S-3'. Phylogenetic analysis, comparison of sequence identities and the arrangement in the rRNA gene subunits suggested that this isolate is separate from other Nosema species.  相似文献   

13.
One of three (33%) captive specimens of Oustalet's chameleon, Furcifer oustaleti (Mocquard) originally from Madagascar and housed at the Oklahoma City Zoological Park Herpetarium, Oklahoma County, Oklahoma, USA, was found to be passing an undescribed species of Choleoeimeria in its faeces. Oocysts of Choleoeimeria fischeri sp. n. were cylindroidal, 30.3 x 16.8 (28-34 x 15-18) microm, with a smooth, bilayered wall and a length/width ratio (L/W) of 1.8. A micropyle and oocyst residuum was absent but a fragmented polar granule was often present. Sporocysts were ovoidal, 9.6 x 8.0 (9-10 x 7-9) jm, with an L/W of 1.2. Stieda, sub-Stieda, and para-Stieda bodies were absent. The sporocyst residuum consists of large globules dispersed between sporozoites. Sporozoites were elongate, 8.6 x 2.9 (8-10 x 2-3) microm, with an elongate posterior refractile body. The new species represents the second coccidian described from this lizard.  相似文献   

14.
Myxidium biliare sp. n., a new myxosporean species parasitizing the gall bladder of Galaxias maculatus (Jenyns), in Patagonia, is described. Its coelozoic plasmodia were floating free in the bile. Spores are fusiform 13.7 +/- 0.9 microm long and 6.9 +/- 0.6 microm wide, with rounded ends in frontal view and slightly pointed ends in sutural view; shell with ridges and sinuous sutural line. Both maximum prevalence and maximum percentage of immature plasmodia occurred in summer. In winter the prevalence and the percentage of immature plasmodia fell to their lowest values. Prevalence was independent of host sex but increased with host length. Prevalence in 15 Patagonian Andean lakes (situated from 39 degrees 25'S to 41 degrees 30'S) ranged between 4.2% and 70%.  相似文献   

15.
The oocyst morphology and endogenous development of Eimeria stigmosa Klimes, 1963 in a domestic goose (Anser anser domesticus L.) was studied using light and electron microscopy. The oocyst wall consisted of two layers. The outer layer formed densely accumulated protrusions, whilst the inner layer was smooth and formed a collar structure around the micropyle. Meronts were observed in the posterior part of the jejunum, along the whole length of the ileum and in Meckel's diverticulum within 1-4 days post infection (DPI). Sexual generation was found in the caecum and colon 4-5 DPI. All endogenous stages were located intranuclearly in enterocytes, predominantly in the apical part of the villi in distinct parasitophorous vacuoles. Numerous different developmental stages were frequently found in one nucleus. Current evidence indicates the existence of only one asexual generation formed by ectomerogony. During the development of asexual stages, invaginations into the body of a meront by the host cell nucleoplasm were observed.  相似文献   

16.
A species not identifiable with any of the about 23 Myxobolus species recorded from the common carp so far, was detected in the gills of one- and two-summer-old specimens of the common carp ((Cyprinus carpio L.) cultured in pond farms in Hungary. The strictly tissue-specific plasmodia of the parasite were located, surrounded by hyaline cartilage cells, in the chondrous substance of the terminal parts of the gill arches and in the cartilage structure ventrally connecting the gill arches. The spores of the parasite described as Myxobolus intrachondrealis sp. n. developed in globular or ellipsoidal plasmodia measuring 300-600 microm. By their elongated ellipsoidal shape and similarly elongated polar capsules the spores were well distinguishable from the hitherto described Myxobolus species parasitic in the common carp and also from the cartilage-parasitic Myxobolus species of other fishes.  相似文献   

17.
We investigated the genotypes of Cryptosporidium infecting red squirrels (Sciurus vulgaris L.) in two areas of the Western Alps in Italy. Examination of 141 faecal samples from 70 red squirrels revealed oocysts of Cryptosporidium in 17 animals (24.3%). Based on 18S rRNA gene sequencing, two genotypes of Cryptosporidium species were found: 15 squirrels were positive for the Cryptosporidium ferret genotype and 2 for the Cryptosporidium chipmunk genotype I. The occurrence and intensity of Cryptosporidium infection did not differ between the study areas or sex. More than 85% of the positive animals were adults; however no difference was found between Cryptosporidium infection in the juvenile and adult age groups. Oocysts of the Cryptosporidium ferret genotype measured 5.5 +/- 0.3 x 5.2 +/- 0.2 microm (shape index 1.06) and the Cryptosporidium chipmunk genotype I 5.8 +/- 0.3 x 5.4 +/- 0.3 microm (shape index 1.07). Neonatal and adult CD1 and BABL/c mice inoculated with 1 x 10(3) fresh oocysts of both genotypes did not produce detectable infection.  相似文献   

18.
Eimeria jamescooki sp. n. was recovered from the skink Cryptoblepharus virgatus (Garman) found on the grounds of James Cook University, Townsville (type locality), North Queensland, Australia. Oocysts were 17.5-25.0 (22.1 +/- 1.9) x 15-22.5 (17.7 +/- 1.6) microm and sporocysts 6.25-10.0 (7.9 +/- 1.15) x 3.75-6.25 (5.3 +/- 1.0) microm in size. Endogenous stages are described from histological material examined by light microscope and by transmission electron microscope. Both merogony stages and gamonts were found to develop in the cytoplasm of the anterior gut mucosal epithelium. Meront progeny were comprised of 10 to 21 merozoites. Premature macrogamonts were elongate; some host cells contained two elongate macrogamonts. Unique to the presently described species were the Golgi "plaques" and an enclosure of tubuli. Mature macrogamonts and young oocysts ranged in size from 14 x 7 to 21 x 11 microm and contained two types of wall-forming bodies, canaliculi and amylopectin granules. Differentiating microgamonts conformed in fine structure with that observed in other eimerians. Their sizes increased from 15.4 x 4.2 to 28 x 8.4 microm while dividing to over 70 nuclei, which formed a corresponding yield of microgametes.  相似文献   

19.
Henneguya pilosa sp. n., a new species of myxosporean from the gill filaments of the white piranha, Serrasalmus altuvei Ramirez, 1965 (Characidae), a freshwater teleost fish collected in the Zoological Garden of the city of Teresina (Piauí), Brazil, is described from light and transmission electron microscope observations. This myxosporean produced small plasmodia (up to 0.2 mm in diameter), each one containing all life-cycle stages of the parasite, including numerous spores. The spores, laterally compressed, averaged 54.2 (52.3-56.0) microm in total length and consisted of two unequal valves adhering together along the suture line and two caudal processes. The spore body measured 21.1 (20.0-23.1) microm in length, 5.9 (5.5-6.3) microm in width, and 2.2 (1.9-2.6) microm in thickness. The two equal ellipsoidal polar capsules of 7.4 (7.1-7.6) microm long and 1.2 (1.0-1.3) microm wide possessed a polar filament with 11-12 (rarely 13) turns. All surfaces of the spores were covered with a tightly adherent complex network of numerous densely ramified granulo-fibrillar masses, the longest measuring 1.5 microm long, observed around the caudal processes. The prevalence of infection was 30%. The taxonomic affinities of this parasite with other of the same genus in freshwater South American fish species are discussed.  相似文献   

20.
The egg shell of Huffmanela huffmani Moravec, 1987 forms three main layers: an outer vitelline layer, a middle chitinous layer, and an inner lipid layer. The vitelline layer, forming the superficial projections of the egg shell, comprises two parts: an outer electron-dense, and an inner electron-lucid part. The chitinous layer is differentiated into three parts: an outer homogenous electron-dense part, a lamellated part, and an inner electron-dense net-like part. The lipid layer comprises an outer net-like electron-lucid part, and an inner homogenous electron-lucid part. The polar plugs are formed by electron-lucid material with fine electron-dense fibrils.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号