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PubMed1990

Neospora caninum (Apicomplexa) in an aborted equine fetus.

Tachyzoites of Neospora caninum were found in sections of lung of an equine fetus aborted 2 mo before term. Individual tachyzoites were approximately 3-5 x 2-3 microns, divided by endodyogeny, and stained positively with anti-N. caninum serum but not with anti-Toxoplasma gondii serum. Toxoplasma gondii antibody was not found in the mare's serum. This is the first report of N. caninum in a horse and indicates that N. caninum can be transmitted transplacentally in equids.

Abortion, Veterinary↗
PubMed1990

Description of the oocysts of Eimeria paludosa (Apicomplexa: Eimeriidae) from Fulica americana (Aves: Gruiformes), with comments on synonyms of eimerian species from related birds.

Between November and December 1988, fecal and intestinal contents were collected from 25 northern American coots, Fulica americana americana, in Arkansas and Texas, and examined for coccidial parasites. Seventeen (68%) of the coots were infected with Eimeria paludosa, herein described; for the first time, photomicrographs of the species are presented. Sporulated oocysts are ovoid, 16.5 x 12.6 (15-23 x 11-14) microns, with a lightly to heavily pitted single-layered wall; an oocyst residuum is absent, but a prominent micropyle is present. A large, or several smaller, polar granule(s) is present, usually located beneath the micropyle. Sporocysts are elongate-ovoid, 10.8 x 6.2 (10-12 x 5-7) microns, with Stieda and substieda bodies. A sporocyst residuum is present, normally composed of very fine faint granules scattered among the sporozoites or, rarely, as a spherical mass. Sporozoites are elongate, 8.7 x 2.7 (7-11 x 2-3) microns, in situ. Each sporozoite contains a spherical-ellipsoid posterior refractile body and occasionally a spherical anterior refractile body. A nucleus is located immediately anterior to the posterior refractile body. The occurrence of E. paludosa in F. a. americana is a new host and geographic record for the parasite. In addition, several of the previously described eimerian species from gruiform birds are proposed to be synonyms of E. paludosa.

Animals↗
PubMed1990

Isospora daphnensis n. sp. (Apicomplexa: Eimeriidae) from the medium ground finch (Geospiza fortis) from the Galapagos Islands.

In March and April 1987 fecal samples from 237 nestling birds, including 199 from 85 nest sites of Geospiza fortis, 23 from 12 nest sites of Geospiza scandens, 6 from 2 nest sites of Geospiza magnirostris, and 9 from 2 nest sites of hybrids involving Geospiza fuliginosa and G. fortis, were collected from Daphne Major in the Galapagos archipelago and examined for coccidia. Only 3 of 4 nestlings from 1 nest site of G. fortis (1.5%) had oocysts in their feces. Two of the 3 infected nestlings had concurrent infections of Isospora temeraria, and all 3 nestlings were infected with a new species. Isospora daphnensis n. sp. Sporulated oocysts of I. daphnensis n. sp. are ellipsoidal, 27.3 x 23.6 (22-30 x 20-27) microns; a polar body is present, but no oocyst residuum or micropyle occurs. The oocyst wall, approximately 1.5 microns thick, is composed of a mammillated outer layer and thinner inner layer. Sporocysts are ovoid, 15.2 x 10.2 (15-16 x 9-11) microns and have a nipplelike Stieda body and a small substieda body. The sporocysts contain an irregularly shaped, smoothly contoured residuum with uniform granules and 4 sporozoites with a large refractile body at one end and lying randomly in the sporocysts.

Animals↗
PubMed1990

Ultrastructural observations on the developmental stages of Lankesterella minima (Apicomplexa) in experimentally infected Rana catesbeiana tadpoles.

During May to August 1988, the prevalence of Lankesterella minima in bullfrog tadpoles and adults in the vicinity of Lake Sasajewun, Algonquin Park, Ontario, was 54.8% and 29.4%, respectively. The parasite was transmitted to laboratory-reared tadpoles through the bite of experimentally infected, laboratory-reared leeches (Batracobdella picta). Intraerythrocytic sporozoites were observed in the experimentally infected tadpoles 36 days postexposure (PE) to leech bites. Sporogonic stages in these tadpoles were examined by light and electron microscopy. Oocysts developed in vascular endothelial cells of several organs. Multinucleate oocysts at 29 days PE lay in a parasitophorous vacuole and contained several large inclusions. Mature oocysts, observed 32 days PE, contained about 70 sporozoites that exhibited typical apicomplexan features. In the posterior region of the sporozoites, 12 helically arranged chains of electron-lucent intrapellicular extended anteriorly from a dense terminal ring.

Animals↗
PubMed1990

Effects of sulfadiazine and amprolium on Neospora caninum (Protozoa: Apicomplexa) infections in mice.

An immunosuppressed mouse model was used to determine the effects of amprolium and sulfadiazine on experimental Neospora caninum infections. Both drugs were given in the drinking water. Neither drug was effective in treating infections when given 7 days after inoculation of tachyzoites, when clinical signs of disease had developed. Amprolium did not prevent deaths or development of clinical signs when given in the drinking water at 1 mg/ml or 5 mg/ml 3 days after inoculation of tachyzoites. Sulfadiazine in drinking water was not effective when given at 0.5 mg/ml but was effective in preventing deaths and clinical disease when given at 1 mg/ml 3 days after inoculation with tachyzoites. Most mice (6 of 10) treated for 3 days with 1 mg/ml sulfadiazine in drinking water developed encephalitis after drug treatment was stopped. Treatment for 14 days with 1 mg/ml sulfadiazine in drinking water was needed to protect 90% of inoculated mice.

Acute Disease↗
PubMed1990

Double alteration of the small intestine in conventional and gnotobiotic piglets experimentally infected with the coccidium Isospora suis (Apicomplexa, Eimeriidae).

The pathogenicity of the coccidium Isospora suis was studied in 42 conventional and 26 gnotobiotic piglets at 1-13 days post infection (DPI). The prepatent period of the coccidium I. suis was 4.5-5 days. Only in one experiment in conventional piglets the prepatent period of 3.5 days was recorded. At least 9 days pathogenesis of I. suis was recorded during which double alteration of the small intestine occurred. The first alteration was found at 3-4 DPI. The second phase of alterative changes was observed at 8-9 DPI. In comparison with gnotobiotic piglets in conventional piglets clinical signs and pathological changes used to appear one day sooner but reparation and regeneration of alterative changes was quicker. In the first phase of the infection (3-7 or 8 DPI) the heaviest pathological changes were in the posterior jejunum. In the second phase of the infection (8 or 9-12 DPI) the heaviest changes were in the middle jejunum. In short period repeated lesions of mucosal barrier of the small intestine multiply the pathogenicity of I. suis and rank I. suis in front place among other enteropathogens of nursing piglets.

Animals↗
PubMed1990

Coccidia (Apicomplexa) from heteromyid rodents in the southwestern United States, Baja California, and northern Mexico with three new species from Chaetodipus hispidus.

Fecal samples from 223 heteromyid rodents of 4 genera and 13 species were collected from California, New Mexico, and Texas and from Baja California Norte and Sonora, Mexico. Of these, 84 (38%) were infected with coccidian oocysts; 72 of 84 (86%) infected animals had only 1 species of coccidian. Eleven species of coccidia were identified including 1 cyclosporan and 10 eimerians; the cyclosporan and 2 of the eimerians are described as new species. Sporulated oocysts of Cyclospora angimurinensis n. sp. were subspheroidal, 21.9 x 19.3 (19-24 x 16-22) microns, with sporocysts lemon-shaped, 11.9 x 9.5 (9-15 x 8-11) microns; it was found in 1 of 20 (4%) Chaetodipus hispidus. Sporulated oocysts of Eimeria chaetodipi n. sp. were subspheroidal, 16.7 x 14.6 (13-19.5 x 12-17) microns, with sporocysts ovoidal, 8.7 x 6.6 (7.5-10.5 x 5-7.5) microns; it was found in 3 of 20 (15%) C. hispidus. Sporulated oocysts of Eimeria hispidensis n. sp. were subspheroidal, 20.5 x 17.4 (17-23 x 14-21) microns, with sporocysts lemon-shaped, 9.3 x 7.2 (7.5-10.5 x 5-9) microns; it was found in 4 of 20 (20%) C. hispidus.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

First record of Ascogregarina taiwanensis (Apicomplexa: Lecudinidae) in North American Aedes albopictus.

Aedes albopictus collected in the East St. Louis, Illinois, area were found infected with the gregarine protozoan, Ascogregarina taiwanensis. Infection rates varied from 67 to 95% at 4 sites and 0 to 10% at 2 others. Lower infection levels were found in Ae. epactius (42%) and Culex restuans (one larva). Four mosquito species were cross-infected in the laboratory with gregarines isolated from field-collected hosts. Aedes atropalpus was 90% susceptible to A. taiwanensis (100% in Ae. albopictus), with abnormal development and some melanization of trophozoites and gametocysts. In Ae. aegypti and Cx. restuans, the experimental infection was much lower (12-56%) and exhibited abnormalities similar to the Ae. atropalpus infections. Ascogregarina oocysts recovered from both Ae. aegypti and Ae. atropalpus hosts were subsequently infective to Ae. albopictus. In Ae. triseriatus, A. taiwanensis infection was very low (25%, 1-2 trophozoites per larva); gametocysts were not observed nor were infectious oocysts obtained. We conclude that A. taiwanensis, newly introduced to the USA with Ae. albopictus, can develop in 4 indigenous mosquito species and can produce deleterious effects in at least 2, Ae. aegypti and Ae. atropalpus.

Aedes↗
PubMed1990

Three new species of Eimeria (Apicomplexa: Eimeriidae) from Apalone spinifera pallidus (Testudines: Trionychidae) in Texas, with a redescription of E. amydae.

Three new species of Eimeria are described from pallid spiny softshells, Apalone spinifera pallidus, collected in north-central Texas. Oocysts of Eimeria spinifera n. sp. were found in the feces of 3/9 (33%) turtles and are subspheroid, ellipsoid, or pear-shaped, 16.3 x 14.0 (14-19 x 12-18) microns, with a thin, single-layered wall; shape index 1.2 (1.1-1.3). A micropyle is absent, but an oocyst residuum is present; polar granule present in 16% of the oocysts. Sporocysts are elongate-ovoid, 10.3 x 5.2 (8-12 x 5-6) microns, each with a Stieda body bearing short filaments. Oocysts of Eimeria apalone n. sp. were found in 5/9 (56%) turtles and are ellipsoid, elongate pear-shaped, or subspheroid, 16.8 x 13.2 (12-19 x 10-16) microns, with a thin, single-layered wall; shape index 1.3 (1.0-1.5). A micropyle, oocyst residuum, and polar granule are absent. Sporocysts are elongate-ovoid, 11.3 x 6.2 (9-14 x 5-7) microns, each with a prominent Stieda body. Oocysts of Eimeria pallidus n. sp. were found in 4/9 (44%) A. s. pallidus and are spheroid or subspheroid, 23.4 x 21.6 (18-27 x 17-25) microns, with a thin, single-layered wall; shape index 1.1 (1.0-1.3). A micropyle is absent, but an oocyst residuum is present; polar granule present in 20% of the oocysts. Sporocysts are elongate-ovoid, 14.3 x 6.2 (13-17 x 6-7) microns, each with a Stieda body and short filaments. In addition to the new species, 3 previously described eimerians, including Eimeria amydae Roudabush, 1937, which is redescribed, were also found.

Animals↗
PubMed1989

Pathogenesis of Sarcocystis falcatula (Apicomplexa: Sarcocystidae) in the budgerigar (Melopsittacus undulatus). III. Pathologic and quantitative parasitologic analysis of extrapulmonary disease.

Forty-four budgerigars (Melopsittacus undulatus) were administered sporocysts of Sarcocystis falcatula orally and were examined at necropsy intervals from less than 12 hr to 168 days. Tissue were examined by touch preparations (of organ cut surfaces), light microscopy, and electron microscopy. Meront and cyst burdens were determined in various organs and correlated with duration of infection, inoculum, and the meront or cyst burdens of other organs. Host inflammatory tissue reactions were quantitated and correlated with meront and cyst burdens. Quantitation of meronts was more accurate in tissue sections than in touch preparations, but quantitation of merozoites was better in touch preparations. More than 97% of meronts were found in capillary, venular, and venous endothelial cells. Cysts were found only in cardiac and skeletal myocytes. Merogony began in the lamina propria of the small intestine less than 12 hr postinoculation (PI). Meronts were in liver and lung by the second day PI and in other organs by 3-7 days PI. Mean meront burdens were highest in lung (33 meronts/mm2), lower in liver and kidney (1-3 meronts/mm2), and infrequent in other organs (less than 0.9 meronts/mm2). Cysts were first seen in cardiac myocytes 7 days PI. They developed through the metrocyte stage and then degenerated, rarely reaching maturity. Cysts were first noted in skeletal muscle at 8 days PI. In leg, upper esophagus, and tongue, cysts matured between 44 and 77 days PI. In pectoral muscles, the majority of cysts degenerated during the late metrocyte and early intermediate stages (28-42 days PI). In addition to a previously reported and often fatal acute interstitial pneumonitis, S. falcatula-infected budgerigars also sustained a chronic active hepatitis, interstitial myocarditis, myositis, nephritis, splenitis, and encephalitis. These lesions weakly correlated with meront burdens in most sites during early infection (up to 50 days PI).

Animals↗
PubMed1989

Ultrastructural development of the sarcocyst of Sarcocystis rauschorum (Apicomplexa: Sarcocystidae) in the varying lemming Dicrostonyx richardsoni.

The development of the sarcocyst of Sarcocystis rauschorum in its intermediate host was studied. Lemmings were orally administered sporocysts of S. rauschorum obtained from snowy owls (Nyctea scandiaca). Beginning at 9 days postinoculation (DPI) and at various intervals to 84 DPI, skeletal muscle tissue taken from the infected lemmings was examined by electron microscopy. At 9 DPI the sarcocysts contained few metrocytes and the cyst wall was flat. The metrocytes underwent endodyogeny, and within a few days the cyst wall of the rapidly growing sarcocyst developed numerous tubulovesicular invaginations into the electron-dense layer, and the wall had a few irregular infoldings. By 21 DPI, banana-shaped bradyzoites appeared, and by 84 DPI the mature cysts were filled with bradyzoites in groups subdivided by septa and by deep infoldings of the cyst wall. The fine structure of the wall remained simple throughout maturation, with no conspicuous invagination or protrusion. The sarcocyst produced in response to S. rauschorum is unlike those from many species of Sarcocystis, which have complex walls that change markedly as the sarcocysts mature; however, its simple appearance is similar to other species that have rodents as intermediate hosts and raptorial birds as definitive hosts.

Animals↗
PubMed1989

Serial transmission of Caryospora bigenetica Wacha and Christiansen, 1982 (Apicomplexa: Eimeriidae) between different species of rodents.

Transmission of Caryospora bigenetica by cannibalism between cotton rats, between cotton rats and mice, and between mice was demonstrated. All experimental animals developed swollen muzzles and scrota 8 days after ingestion of infected tissues. Infections were confirmed by light microscopy of fresh tissue smears. Tissues of cannibalized animals contained caryocysts that, after ingestion by the next host, released sporozoites that underwent merogony, gamogony, sporogony, and caryocyst formation in dermal tissues. This study demonstrates that C. bigenetica can be transmitted by predation between species of rodents and that, in the recipient host, asexual and sexual reproduction occur before caryocysts appear.

Animals↗
PubMed1989

Coccidian parasites (Apicomplexa: Eimeriidae) from two species of caimans, Caiman yacare daudin and Caiman latirostris daudin (Alligatoridae), from Paraguay.

From October 1986 to January 1987, feces from 119 Caiman yacare and 12 Caiman latirostris were collected in Paraguay and later examined for coccidian oocysts; 69 of 119 (58%) samples from C. yacare and 3 of 12 (25%) samples from C. latirostris contained coccidian oocysts. Two eimerians infected C. yacare and both are described as new species. Sporulated oocysts of Eimeria paraguayensis n. sp. are ellipsoid, 34.0 x 23.6 (26-38 x 20-29) microns with sporocysts ovoid, 14.0 x 7.1 (10-19 x 6-10) microns. Sporulated oocysts of Eimeria caimani n. sp. are spheroid, 22.4 (19-29) microns with sporocysts ovoidal, 12.9 x 6.5 (8-17 x 5-8) microns. Isospora jacarei infected C. latirostris and is redescribed. Sporulated oocysts of I. jacarei are sub-spheroid, 13.2 x 12.1 (10-18 x 10-15) microns with sporocysts ellipsoid, 10.4 x 5.8 (7-13 x 4-11) microns. To date, members of the Eimeriidae found in Crocodylia include 5 species of Eimeria and 2 of Isospora including the new species described here.

Alligators and Crocodiles↗
PubMed1989

Coccidian parasites (Apicomplexa: Eimeriidae) from insectivores. VII. Six new species from the hairy-tailed mole, Parascalops breweri.

Sixteen hairy-tailed moles, Parascalops breweri, collected from the northeastern U.S.A. were examined for coccidian oocysts; all were infected with multiple species of coccidia and 3 genera were represented. Two cyclosporans, 2 eimerians, and 2 isosporans are described as new species. Sporulated oocysts of Cyclospora ashtabulensis n. sp. are subspheroid to ellipsoid, 18 X 14 (14-23 X 11-19) microns, and sporocysts are ovoid, 12 X 7 (8-14 X 5-9) microns; C. ashtabulensis was found in 7 of 16 (44%) moles. Sporulated oocysts of Cyclospora parascalopi n. sp. are spheroid, 17 X 14 (13-20 X 11-20) microns, and sporocysts are ovoid, 11 X 7 (8-14 X 5-8) microns; C. parascalopi was found in 8 of 16 (50%) moles. Sporulated oocysts of Eimeria aethiospora n. sp. are subspheroid to ellipsoid, 19 X 13 (15-24 X 10-16) microns, and sporocysts are ovoid, 11 X 6 (8-13 X 4-7) microns; E. aethiospora was found in 4 of 16 (25%) moles. Sporulated oocysts of Eimeria titthus n. sp. are subspheroid, 16 X 14 (13-19 X 11-17) microns, and sporocysts are ellipsoid, 11 X 6 (9-13 X 4-7) microns; E. titthus was found in 4 of 16 (25%) moles. Sporulated oocysts of Isospora ashtabulensis n. sp. are ellipsoid, 20 X 14 (16-24 X 10-18) microns, and sporocysts are ovoid, 10 X 7 (7-14 X 5-10) microns; I. ashtabulensis was found in 5 of 16 (31%) moles.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1989

Coccidian parasites (Apicomplexa: Eimeriidae) from insectivores. VIII. Four new species from the star-nosed mole, Condylura cristata.

Twenty-four star-nosed moles, Condylura cristata, collected from the northeastern United States (Maine, Massachusetts, Ohio, Vermont) were examined for coccidian oocysts. All of the moles were infected with from 1 to 4 species of coccidia representing 2 eimerian and 3 isosporan spp., but oocysts of only 4 of these species were present in sufficient numbers for detailed study; these are described as new. Sporulated oocysts of Eimeria condylurae n. sp. were subspheroid, 17.7 x 15.7 (17-23 x 14-21) microns, with sporocysts ellipsoid, 11.7 x 5.6 (11-14 x 5-6) microns; E. condylurae was found in 3 of 24 (12.5%) moles. Sporulated oocysts of Isospora condylurae n. sp. were ellipsoid, 19.4 x 9.3 (17-21 x 8-11) microns, with sporocysts ovoid, 11.7 x 5.8 (11-13 x 5-7) microns; I. condylurae was found in 12 of 24 (50%) moles. Sporulated oocysts of Isospora cristatae n. sp. were ellipsoid, 15.7 x 10.1 (13-18 x 9-13) microns, with sporocysts ovoid, 11.0 x 5.7 (10-12 x 5-7) microns; I. cristatae was found in 19 of 24 (79%) moles. Sporulated oocysts of Isospora lamoillensis n. sp. were ellipsoid, tapering at both ends, 21.6 x 13.0 (19-23 x 11-14) microns, with sporocysts spindle-shaped, 14.9 x 7.7 (14-16 x 7-8) microns; I. lamoillensis was found in 2 of 24 (8%) moles. Although the second eimerian seen was in 7 of the 24 (29%) moles from Massachusetts, Ohio, and Vermont, there were not enough sporulated oocysts to study in detail to warrant a new species description.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1989

Fine structure of Perkinsus atlanticus n. sp. (Apicomplexa, Perkinsea) parasite of the clam Ruditapes decussatus from Portugal.

A new apicomplexan species, Perkinsus atlanticus, is described from gill filaments of the clam Ruditapes decussatus (Bivalvia) from Portugal, where it causes great mortality. The zoospores differ from those of other species of Perkinsus in size and shape, dimensions, insertion of the 2 flagella, and in the identity of the host. On the other hand, the life cycle stages showed some ultrastructural differences compared with Perkinsus marinus, the only species previously studied in detail. When the clams were parasitized heavily, ultrastructurally similar life cycle stages were found in foot and mantle tissues.

Animals↗
PubMed1989

Eimeria lancasterensis (Apicomplexa: Eimeriidae) from the eastern fox squirrel, Sciurus niger (Rodentia: Sciuridae), in north-central Texas.

Eimeria lancasterensis Joseph, 1969, is reported for the first time from the feces of 10 of 11 (91%) eastern fox squirrels, Sciurus niger ludovicianus, in Dallas and Johnson counties, Texas. Oocyst measurements were similar to those reported previously from the eastern gray squirrel, Sciurus carolinensis carolinensis, in Massachusetts. Except for our observation of a substieda body, oocyst morphology was identical to the original description of E. lancasterensis.

Animals↗