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PubMed2005

[The structural and functional analysis of the surface apparatus in four species of Sarcocystis (Sporozoa, Apicomplexa)].

The comparable ultrastructural analysis of the sarcocyst surface apparatus (SSA) was made for four species of Sarcocystis: Sarcocystis muris, S. fusiformis, S. medusiformis, and Sarcocystis sp. from buffalo heart muscles. In all these species, SSA contains a surface membrane, overmembrane complex with glycocalyx, and submembrane complex made of two glycoprotein SSA primembrane layers. SSA makes numerous primary vesicle-like protrusions and pits in between. Some vesicles containing two layers, PM1 and PM2, are pinching off from the totally formed protrusions. Then these vesicles are directed into infected host cell to participate in its degradation. In the SSA pits neither over-, nor submembrane complex is present, the pits being made of the surface membrane only. It is important that fibrillar structures penetrate through the SSA membrane into pits from the host cell. Besides, SSA forms secondary protrusions with different structures in various species of Sarcocystis. They increase the sarcocyst surface and transport different substances along intermediate filaments from the SSA pits membrane to the sarcocyst body. At the same time, deep invaginations are found in the SSA of old sarcocysts. We thought that these structures increased the sarcocyst surface and thus promote to intensify metabolism. This study-defined presence of membranous vesicles in secondary protrusions. According to their structure and localization, the membranous vesicles may be involved in the building of the sarcocyst surface membrane.

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PubMedDate not supplied

[An outbreak of coccidiosis in partridge (Rhynchotus rufescens), reared in captivity, by Eimeria rhynchoti Reis and Nobrega, 1936 (Apicomplexa: Emeriidae)].

Eimeria rhynchoti is redescribed parasitizing partridge (Rhynchotus rufescens), reared in captivity, from Jaboticabal City, São Paulo State, Brazil. Sporulation takes place in 48 hours, the shape of oocysts found vary from spherical to elliptic with 23.01 micro +/- 1.57 of length by 21.0 micro +/- 1.78 of width. The microple, polar cap and residuum of the oocysts were absent. The oocyst wall, measures 2.2 micro +/- 0.31 of thickness, is composed by two smooth layers; the polar granule is present. The sporocysts length was 15.03 mm +/- 2.12 by 8.08 mm +/- 0.84 of width vary from elliptic to elongate. Sporocyst wall slender with is fine and Stieda body; the residue found in form of several smaller granules spherical compacts. The sporozoites are contrary extending along the sporocysts wall possessing refracts body of easy visualization.

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PubMed1999

Parasites of Chaffinch (Fringilla coelebs) population. Part I. Coccidia (Protozoa, Apicomplexa).

Coccidia infection in Chaffinch population in Mazurian Lakeland was studied. Birds were caught in mist nets from June to September and droppings were collected after defecation. Prevalence of infection was high -80% of Chaffinches excreted oocysts of Isospora sp. Intensity of oocysts' production varied depending on the time of the day and therefore coccidia prevalence in Chaffinch should be best detectable in birds caught after midday.

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PubMed2006

New species of Choleoeimeria (Apicomplexa: Eimeriidae) from the veiled chameleon, Chamaeleo calyptratus (Sauria: Chamaeleonidae), with taxonomic revision of eimerian coccidia from chameleons.

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 Modrý 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.

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PubMed2006

Eimeria gazani n. sp. (Apicomplexa:Eimeriidae) from the lizard, Scincus hemprichii (Sauria:Scincidae) in Saudi Arabia.

Eimeria gazani n. sp. was described from the intestine of the lizard, Scincus hemprichii captured at Gazan, western region. Sporulated oocysts ovoidal 23.5 x 19.7 (20.8-25.0 x 19.0-21.2) micro m, with smooth brownish-green bilayered wall. Micropyle present, covered by a dome-shaped cap. Oocyst residu-um and polar granule are present. Sporocysts ellipsoidal, 10.8 x 6.9 (10.0-11.4 x 6.1-7.4) microm., with a prominent Stieda body. Sporocyst residuum present, sporozoites elongate, laying head to tail in sporocysts, each with large and small subspherical refractile globule.

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PubMed1992

Experimental Caryospora bigenetica (Apicomplexa: Eimeriidae) infections in swine (Sus scrofa).

Two Hampshire-Landrace crossbred pigs were found to contain developmental stages of Caryospora bigenetica following oral inoculation with 1 x 10(8) oocysts. One pig was given intramuscular injections of methylprednisolone acetate. Both pigs displayed clinical signs of dermal coccidiosis from 3 to 10 days after inoculation, including swollen jowls and hocks, bilateral ocular discharges, generalized erythema, and lethargy. Meronts and gamonts were observed histologically in numerous tissues including jowl, ear, footpad, tongue, and lung at 10 days postinoculation. The present study is the first report of C. bigenetica infections in swine.

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PubMed1991

New host and locality records of coccidia (Apicomplexa: Eimeriidae) from rodents in the southwestern and western United States.

One hundred forty-seven murid and heteromyid rodents were collected from various sites in the southwestern and western United States (Arizona, Colorado, New Mexico, Texas, and Utah) and Baja California Norte, Mexico, and their feces were examined for coccidial parasites. Of these, 53 (36%) were infected with at least 1 coccidian; 45 of 53 (85%) of the infected rodents harbored only 1 species of coccidian. Infected rodents included: 10 of 22 (45%) Neotoma albigula, 3 of 11 (27%) Neotoma floridana, 2 of 14 (14%) Neotoma lepida, 15 of 29 (52%) Neotoma micropus, 5 of 8 (63%) Peromyscus crinitis, 6 of 6 (100%) Peromyscus difficilis, 1 of 2 (50%) Peromyscus eremicus, 9 of 34 (26%) Sigmodon hispidis, and 2 of 3 (67%) Sigmodon ochrognathus; 4 Neotoma cinerea, 3 Neotoma devia, 3 Neotoma mexicana, 1 Peromyscus maniculatus, 1 Onychomys leucogaster, 1 Onychomys torridus, 3 Chaetodipus fallax, and 2 Chaetodipus penicillatus were negative. Although no new species was found, the following coccidians were identified from infected rodents: Eimeria albigulae from N. albigula, N. floridana, and N. micropus, Eimeria antonellii from N. albigula and N. micropus, Eimeria ladronensis from N. albigula, N. floridana, N. lepida, and N. micropus, Eimeria arizonensis and Eimeria lachrymalis from P. crinitis and P. difficilis, Eimeria lachrymalis from P. eremicus, Eimeria tuskeegensis from S. ochrognathus, and Eimeria roperi, Eimeria sigmodontis, Eimeria tuskeegensis, Eimeria webbae, and an unidentified species of Eimeria from S. hispidis. This report documents 12 new host and several distributional records for Eimeria species from murid rodents in Arizona, Texas, and Utah.

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PubMed1991

A new species of coccidian (Apicomplexa: Eimeriidae) from the prairie racerunner, Cnemidophorus sexlineatus viridis (Sauria: Teiidae), in Arkansas.

Feces from 26 prairie racerunners, Cnemidophorus sexlineatus viridis Lowe, 1966, from Arkansas, were examined for coccidian parasites. One of these was found to be infected with oocysts of an undescribed eimerian, which is described herein as new. Sporulated oocysts of Eimeria sexlineatus n. sp. were cylindrical, 30.4 x 17.1 (28-32 x 16-19) microns, with a shape index (length/width) of 1.8 (1.6-2.0). A micropyle and oocyst residuum were absent but 1 (to several) polar granule(s) was present. Sporocysts were ellipsoidal, 10.7 x 8.5 (9.6-11.2 x 8.0-8.8) microns, with a shape index of 1.3 (1.2-1.4). A sporocyst residuum was present but Stieda, substieda, and parastieda bodies were absent. Sporozoites were elongate, 13.2 x 2.7 microns (12.0-14.4 x 2.4-3.2) in situ, containing a single, spherical posterior refractile body. Oocysts and endogenous developmental stages were found within the gall bladder epithelium of the infected lizard. This represents the first time a coccidian has been reported from a North American whiptail lizard.

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PubMed1991

Simultaneous purification of merozoites and schizonts of Eimeria tenella (Apicomplexa) by Percoll flotation and assessment of cell viability with a double fluorescent dye assay.

The asynchronous development of Eimeria tenella in orally infected chickens makes it possible to purify second generation merozoites (meros) and shizonts from a single mucosal homogenate. After centrifugation in 30% Percoll in phosphate-buffered saline (Percoll-PBS), debris, villi, and schizonts float, whereas meros and erythrocytes are pelleted. Erythrocytes are lysed by a mild hypotonic shock; meros are filtered through a cotton wool plug and collected by centrifugation. The 30% Percoll-PBS supernatant fraction is diluted to 25% Percoll-PBS and centrifuged to sediment mature schizonts. By repeated slow-speed centrifugation, schizonts are separated from nuclei and small-sized debris. In less than 3 hr, 8.8 +/- 2.3 x 10(8) meros and 7.2 +/- 3.9 x 10(6) schizonts are collected from 10 infected chickens. Contamination with host material is 2% for meros but variable for schizonts. For the assessment of cell viability, ethidium bromide (EB) and acridine orange (AO) have been used as markers for dead and living cells, respectively, in a single step method. More than 95% of the schizonts and meros accumulate AO and no EB, whereas lysed erythrocytes and all cells hosting a schizont are permeable to EB. After incubation of meros and schizonts in synthetic media with [5,6- 3H]uracil, label accumulates in the perchloric acid-soluble and -insoluble fractions, indicating transport, salvage, and incorporation of the pyrimidine precursor in nucleic acids. If stored on ice, meros and schizonts retain metabolic activity for at least 5 hr, but metabolism declines rapidly during incubation at 41 C.

Acridine Orange↗
PubMedDate not supplied

Isospora mcquistioni and Isospora bioccai (Apicomplexa, Eimeriidae): two new coccidian parasites from Carduelis sinica (Passeriformes, Fringillidae).

The following two species are described from Carduelis sinica (Greenfinch) from Italy. The oocysts of Isospora mcquistioni n. sp. were 26.0 x 22.6 (24.0-28.5 x 20.0-24.2) microns and ovoid with a smooth bilayered wall. Neither micropyle nor oocyst residuum were observed. One polar granule was found. Sporocysts were oval, 18.1 x 11.4 (16.0-19.8 x 11.0-12.0) microns, and with a symmetrical Stieda complex. The residuum was compact and spherical. Isospora bioccai n. sp. oocysts were spherical to subspherical and 24.0 x 23.6 (22.0-26.0 x 21.0-25.8) microns. The oocyst wall was smooth and bilayered. A micropyle and oocyst residuum were absent; 4 to 10 elongate polar granules were present. Sporocysts were 19.5 x 11.6 (18.0-20.0 x 10.0-12.4) microns, ellipsoidal, and with a symmetrical Stieda complex. The sporocyst residuum was diffuse and composed of a few granules.

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PubMed1991

Redescription of Eimeria gazella Musaev, 1970 (Apicomplexa: Eimeriidae) from the Arabian gazelle, Gazella gazella arabica (Artiodactyla: Bovidae) in Saudi Arabia.

Eimeria gazella Musaev, 1970 is redescribed for the first time from the feces of 3 of 6 Arabian gazelles, Gazella gazella arabica from the Riyadh Zoo in Saudi Arabia. Oocyst measurements were similar to those reported previously from the goitered gazelle, Gazella subgutturosa, in Kazakhstan (USSR). Except for our observation of many small polar granules, and Stieda body, oocyst morphology was identical to the original description of E. gazella.

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PubMed1991

Sarcocystis neurona n. sp. (Protozoa: Apicomplexa), the etiologic agent of equine protozoal myeloencephalitis.

Sarcocystis neuronan n. sp. is proposed for the apicomplexan taxon associated with myeloencephalitis in horses. Only asexual stages of this parasite presently are known, and they are found within neuronal cells and leukocytes of the brain and spinal cord. The parasite is located in the host cell cytoplasm, does not have a parasitophorous vacuole, and divides by endopolygeny. Schizonts are 5-35 microns x 5-20 microns and contain 4-40 merozoites arranged in a rosette around a prominent residual body. Merozoites are approximately 4 x 1 micron, have a central nucleus, and lack rhoptries. Schizonts and merozoites react with Sarcocystis cruzi antiserum but not with Caryospora bigenetica. Toxoplasma gondii, Hammondia hammondi, or Neospora caninum antisera in an immunohistochemical test.

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PubMed1991

Sarcocystis canis n. sp. (Apicomplexa: Sarcocystidae), the etiologic agent of generalized coccidiosis in dogs.

Sarcocystis canis n. sp. is proposed for the protozoon associated with encephalitis, hepatitis, and generalized coccidiosis in dogs. Only asexual stages are known in macrophages, neurons, dermal, and other cells of the body. The parasite is located free in the host cell cytoplasm without a parasitophorous vacuole; schizonts divide by endopolygeny. Schizonts are 5-25 x 4-20 microns and contain 6-40 merozoites. Merozoites are approximately 5-7 microns x 1 micron and do not contain rhoptries. The parasite is PAS-negative and reacts with Sarcocystis cruzi antiserum but not with Toxoplasma gondii, Neospora caninum, or Caryospora bigenetica antisera in an immunohistochemical test.

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PubMed1991

Effects of route of inoculation on the site of development of Caryospora bigenetica (Apicomplexa: Eimeriidae).

The sites of infection by Caryospora bigenetica in Swiss-Webster mice (Mus musculus) were demonstrated after 7 routes of inoculation: oral, intraperitoneal, intravenous, intramuscular, subcutaneous, dermal, and intraocular. All mice exhibited clinical signs of dermal coccidiosis 9 days after inoculation regardless of the inoculation route. Signs included swelling of the facial tissue, footpads, and scrota (male mice). Developmental stages of the parasite were found in the muzzle, tongue, footpad, lumbar subcutaneous tissue, biceps femoris muscle, conjunctiva, and eye; the latter 3 sites represent new sites of development. The site of development of the parasite in the host tissue was independent of experimental inoculation route.

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PubMed1991

Coccidian parasites (Apicomplexa: Eimeriidae) of Graptemys caglei and Graptemys versa (Testudines: Emydidae) from Texas.

Nineteen map turtles, Graptemys caglei and Graptemys versa were collected from the Guadalupe and Colorado River watersheds of south-central Texas and examined for coccidial parasites. Thirteen of the 19 turtles (68%), including 11 of 16 (69%) G. caglei and 2 of 3 (67%) G. versa, were infected with at least 1 coccidian. Five Eimeria spp. (E. chrysemydis, E. graptemydos, E. lutotestudinis, E. pseudogeographica, and E. trachemydis) were harbored by G. caglei, and 2 eimerians (E. graptemydos and E. mitraria) infected G. versa. This represents new host records for these previously described coccidians and is the first time parasites have been documented in turtles of both species.

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PubMed1990

Infections in mice with tachyzoites and bradyzoites of Neospora caninum (Protozoa: Apicomplexa).

Tachyzoites of 2 isolates of Neospora caninum (NC-1 and NC-2) were inoculated subcutaneously (s.c.), intraperitoneally (i.p.), or orally into mice to compare the effects of route of inoculation on pathogenicity. Mice developed more severe disease, and disease occurred sooner when inoculated with the NC-1 isolate compared to the NC-2 isolate. Deaths occurred earlier in mice inoculated i.p. with either isolate. Mice inoculated orally or s.c. with tachyzoites responded similarly to infection. Tissue cysts of the NC-2 isolate produced infections in mice following oral or s.c. inoculation. Lesions seen in mice inoculated with tachyzoites or bradyzoites were primarily acute pneumonia, myositis, encephalitis, ganglioradiculoneuritis, and pancreatitis. In vitro studies demonstrated that tachyzoites of both isolates were killed by incubation in pepsin-HCl solution but not 1% trypsin solution. Bradyzoites of the NC-2 isolate were able to withstand treatment with pepsin-HCl solution.

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