The Role of Birds as Definitive Hosts and Intermediate Hosts of Heteroxenous Coccidians

ABSTRACT. Sarcocystis- like oocysts-sporocysts were found in four species of owls (Asio otus, Bubo bubo, Strix aluco , and Tyto alba) and in five species of predatory birds (Accipiter gentilis, Accipiter nisus, Buteo buteo. Circus aeruginosus, Falco tinnunculus). In addition, the muscles of 15 of 41 (36.5%) pheasants (Phasianus colchicus) and one of two jays (Garrulus glandarius) were found to harbor three types of Sarcocystis. Three of 15 (20%) infected pheasants had type I cystozoites (6-8 × 2 fim) in muscle homogenates, but sarcocysts were not seen whereas the other 12 infected pheasants had type II cystozoites (16 × 2-3 pm) and sarcocysts (90 × 600 μm) in their muscles. The one infected jay had type III cystozoites (8-10.5 × 2.5-3 μm) and sarcocysts (35-40 × >770 μm) in its muscles.     

Prevalence and ultrastructure of three types of Sarcocystis in mule deer, Odocoileus hemionus (Rafinesque), in Montana

Infection with Sarcocystis (Protozoa: Sarcocystidae) was diagnosed in 130 of 153 (85%) samples of muscle from mule deer around Bozeman, Montana. Three structurally distinct mature and microscopic sarcocysts with characteristic cyst walls were found. Cyst walls of type I sarcocysts were about 2 microns thick and had characteristic inverted tee-shaped villar projections; these cysts were considered to be S. hemionilatrantis Hudkins and Kistner, 1976. Cyst walls in type II sarcocysts were thick-walled (about 7 microns) and their villar projections were 6.7 X 1.1 micron. The core of the villar projections consisted of granular material and some filamentous structures. Bradyzoites were 11.6 X 2.8 microns and were tightly packed in compartments. Cyst walls of type III sarcocysts were also thick-walled (about 9 microns) but the villar projections were 8.5 X 4.7 microns. Bradyzoites were 13 X 3.3 microns and were loosely arranged in compartments.     

Coccidian parasites (Apicomplexa: Eimeriidae) from insectivores. IV. Four new species in Talpa europaea from England

Moles from England were examined for coccidian oocysts and all 64 Talpa europaea were infected; of 64 infected hosts, 56 (88%) had multiple infections representing two to six coccidian species when examined. Oocysts in 31 of the 64 samples remainedunsporulated. Three eimerians and one isosporan were studied from the 33 fecal samples that had sporulated oocysts and these are described as new species; Cyclospora talpae Pellérdy & Tanyi, 1968, and Isospora sofiae (Golemansky, 1978) Levine & Ivens, 1979, are redescribed; and Cyclospora sp., similar to C. talpae, is discussed. Sporulated oocysts of C. talpae are ellipsoidal, 14.3 X 9.6 (12-19 X 6-13) microns with sporocysts ovoid, 9.4 X 5.7 (6-13 X 4-8) microns; it was found in 21 of the 33 (63.6%) sporulated samples. Sporulated oocysts of Cyclospora sp. are subspheroidal to ellipsoidal, 12.5 X 8.9 (10-14 X 6-12) microns with sporocysts ovoid, 8.6 X 5.3 (6-10 X 4-6) microns; it was found in 21 of the 33 (63.6%) sporulated samples. Sporulated oocysts of Eimeria avonensis n. sp. are elongate-ellipsoidal, 15.0 X 9.6 (13-20 X 7-12) microns with sporocysts ovoid, 6.6 X 3.6 (5-9 X 3-7) microns; it was found in 15 of the 33 (45.5%) sporulated samples. Sporulated oocysts of Eimeria berea n. sp. are subspheroidal, 12.1 X 10.5 (10-15 X 8-14) microns with sporocysts ovoid, 6.3 X 3.9 (5-10 X 2-5) microns; it was found in 8 of the 33 (24.2%) sporulated samples.(ABSTRACT TRUNCATED AT 250 WORDS)     

Coccidian parasites (Apicomplexa: Eimeriidae) from insectivores. VI. Six new species from the eastern mole, Scalopus aquaticus

Thirteen eastern moles, Scalopus aquaticus, collected in West Texas were examined for coccidian oocysts; 11 (85%) were infected and eight (73%) of these had multiple infections representing two or more species. One cyclosporan, three eimerians, and two isosporans were studied and all are described as new species. Sporulated oocysts of Cyclospora megacephali n. sp. were subspheroidal, 18.5 X 15.7 (14-21 X 12-18) microns; they had sporocysts pointed at one end with Stieda bodies nearly as wide as the sporocysts themselves, and were 15.0 X 7.2 (11-17 X 6-9) microns; C. megacephali was found in four (31%) hosts. Sporulated oocysts of Eimeria scalopi n. sp. were spheroidal to subspheroidal, 13.6 X 12.6 (11-17 X 11-15) microns with sporocysts lemon-shaped, 8.7 X 5.5 (7-10 X 4-7) microns; it was found in six (46%) hosts. Sporulated oocysts of Eimeria aquatici n. sp. were asymmetrically ellipsoidal, 17.0 X 10.6 (14-20 X 9-14) microns with sporocysts elongately ovoidal, 9.0 X 5.2 (8-11 X 4-6) microns; it was found in two (15%) hosts. Sporulated oocysts of Eimeria motleiensis n. sp. were subspheroidal, 17.0 X 15.3 (15-20 X 13-18) microns with sporocysts ovoidal, 10.7 X 6.8 (10-13 X 6-8) microns; it was found in seven (54%) hosts. Sporulated oocysts of Isospora motleiensis n. sp. were spheroidal to subspheroidal, 13.6 X 12.0 (10-17 X 8-15) microns with sporocysts broadly ovoidal, 9.5 X 6.7 (7-11 X 4-8) microns; it was found in nine (69%) hosts. Sporulated oocysts of Isospora aquatici n. sp. were subspheroidal, 20.9 X 18.4 (15-24 X 13-21) microns with sporocysts ellipsoidal, 11.8 X 9.0 (9-14 X 7-11) microns; it was found in two (15%) hosts.     

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)     

Prevalence and development of two Sarcocystis spp. in the horse (author's transl)

The prevalence of Sarcocystis spp. in horses was investigated in a survey at the Munich abattoir during 1978/79. Muscle specimens (oesophagus, diaphragm, sublingual muscle, myocardium) were examined using tryptic digestion. Out of 200 horses 31 (15.5%) were found to be carriers of sarcocysts. No parasites were found in the myocardium. In three animals sarcocysts could be isolated and differentiated in fresh preparations. Cysts with 5 to 11 microns by less than 0.5 microns hairlike, unstable protrusions were classified as Sarcocystis equicanis, whereas those with 2.5 to 4.5 microns by 0.8 to 1.0 microns fingerlike, stabile protrusions were assigned to be S. fayeri. Histologically S. equicanis cysts were thin-walled and S. fayeri cysts were thick-walled and often striated. For both species the dog acts as final host. A mixture of sporocysts of both species measured: 12.0--14.4 (13.4 +/- 0.7) X 9.3--10.5 (9.8 +/- 0.4) microns. The prepatent period is 11 to 17 days. Two ponies experimentally infected with 100,000 sporocysts each did not show clinical signs. In fresh preparations and in histopathological examinations of biopsied (111th, 130th, 152th, and 165th day post-infection (p.i.) and postmortem material (167th and 189th day p.i.) different developmental stages of sarcocysts of both species were seen and the following pathological alterations observed: circumscribed non-purulent inflammation, moderate Zenker's degeneration of muscle fibres, and degenerated cysts, of which sometimes only parts of the cyst wall were left. In fresh preparations S. equicanis and S. Fayeri could be differentiated 111 days p.i. The observed disappearance of the sarcocysts is suggested to be a self-cleaning process.     

Pathogenesis of Sarcocystis falcatula (Apicomplexa: Sarcocystidae) in the Budgerigar (Melopsittacus undulatus). IV. infrastructure of Developing, Mature and Degenerating Sarcocysts

ABSTRACT. Sarcocysts in cardiac and skeletal muscles of budgerigars (Melopsittacus undulatus) were examined transmission electron microscopically 5 to 168 days after experimental infection with Sarcocystis falcatula. The ultrastnicture of the primary cyst wall, amorphous substance, metrocytes and bradyzoites in developing, degenerating and mature sarcocysts is described and compared with precystic merozoites studied previously. Sufficient morphologic differences between precystic rnerozoites, metrocytes and bradyzoites (cystozoites) were found which seem to justify their semantic differentiation. Significant differences in immature and mature primary cyst wall morphology were encountered. If primary cyst wall morphology is to be used in determination and differentiation of species of Sarcocystis , then caution must be used to employ only mature sarcocysts.     

Pathogenesis of Sarcocystis falcatula (Apicomplexa: Sarcocystidae) in the budgerigar (Melopsittacus undulatus). IV. Ultrastructure of developing, mature and degenerating sarcocysts

Sarcocysts in cardiac and skeletal muscles of budgerigars (Melopsittacus undulatus) were examined transmission electron microscopically 5 to 168 days after experimental infection with Sarcocystis falcatula. The ultrastructure of the primary cyst wall, amorphous substance, metrocytes and bradyzoites in developing, degenerating and mature sarcocysts is described and compared with precystic merozoites studied previously. Sufficient morphologic differences between precystic merozoites, metrocytes and bradyzoites (cystozoites) were found which seem to justify their semantic differentiation. Significant differences in immature and mature primary cyst wall morphology were encountered. If primary cyst wall morphology is to be used in determination and differentiation of species of Sarcocystis, then caution must be used to employ only mature sarcocysts.     

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)     

Four new species of Isospora from the small tree finch (Camarhynchus parvulus) from the Galapagos Islands

Four isosporan species are described from the small tree finch, Camarhynchus parvulus from Isabela Island on the Galapagos Archipelago. Isospora exigua n. sp. oocysts subspheroidal, one-layered, smooth, yellow-brown color, 20.4 X 20.1 (20-23 X 18-23) microns, with no micropyle, residuum, or polar body. Sporocysts ovoidal, 14 X 9.5 (13-15 X 8-10) microns, with small Stieda and substieda bodies and irregular-shaped residuum. Isospora rotunda n. sp. oocysts subspheroidal, single-layered, smooth, yellow-brown wall with large polar body and no micropyle or residuum, 20.9 X 20.8 (20-24 X 19-23) microns. Sporocysts ovoidal, 15 X 9.7 (13-16 X 9-10) microns with knob-like Stieda bodies, prominent substieda bodies and round residuum. Isospora fragmenta n. sp. oocysts subspheroidal with no micropyle or residuum but with many splinter-like polar granules and a smooth, colorless, single-layered wall, 25.3 X 24.2 (24-27 X 23-25) microns. Sporocysts piriform 15.4 X 11.5 (14-17 X 11-12) microns with knob-like Stieda bodies, prominent substieda bodies, and irregular-shaped residuum. Isospora temeraria n. sp. oocysts ellipsoidal with one polar body, no micropyle or residuum, and wall of a single layer, smooth, yellow-brown color, 25.4 X 21.1 (21-30 X 17-23) microns. Sporocysts piriform, 15 X 10 (14-15 X 9-11) microns with knob-like Stieda bodies, prominent substieda bodies, and a round residuum. One woodpecker finch, Cactospiza pallida, was found to be infected with I. exigua, and a warbler finch, Certhidea olivacea was infected with I. fragmenta.     

Prevalence and site specificity of Sarcocystis greineri sarcocysts in Virginia opossum (Didelphis virginiana) in Florida

Sarcocysts of Sarcocystis greineri in the Virginia opossum (Didelphis virginiana) were observed for documenting sarcocyst prevalence, seasonal prevalence, and muscle specificity. Characteristics of sarcocysts found in striated muscle were recorded, as were light microscopy measurements. Overall prevalence of sarcocysts in striated muscle was 10.0% (24/240). No statistical difference (P = 0.156) in prevalence was detected between summer (13.1%; 16/122) and fall (6.7%; 8/118). Sarcocysts were found in muscles of the diaphragm, leg, breast, tongue, back, and esophagus. Diaphragm had the highest specificity of 72.7% (8/11), which was significantly different (P = 0.05) when compared with tongue and esophagus at 16.6% (1/6). Breast and leg muscle had a specificity of sarcocysts of 54.5% (6/11), whereas 27.2% (3/11) of back muscles contained sarcocysts.     

Completion of the life cycle of Sarcocystis zuoi , a parasite from the Norway rat, Rattus norvegicus

Transmission experiments were performed to elucidate the life cycle of Sarcocystis zuoi found in Norway rats ( Rattus norvegicus ) in China. Two king rat snakes ( Elaphe carinata ) fed sarcocysts from the muscles of 4 naturally infected Norway rats shed sporocysts measuring 10.8 ± 0.7 × 8.0 ± 0.7 μm, with a prepatent period of 8-9 days. Sporocysts from the intestine of 2 experimentally infected king rat snakes were given to the laboratory Sprague-Dawley (SD) rats ( R. norvegicus ) and Kunming (KM) mice ( Mus musculus ). Microscopic sarcocysts developed in the skeletal muscles of SD rats. No sarcocysts were observed in KM mice. Characters of ultrastructure and molecule of sarcocysts from SD rats were confirmed as S. zuoi . Our results indicate that king rat snake is the definitive host of S. zuoi .     

A species of Sarcocystis using owls as definitive hosts.

Sporulated oocysts found in the intestines of a Masked Owl (Tyto novaehollandiae) and a Barn Owl (T. alba) produced sarcocysts in mice. Schizonts were found in the livers of 3 mice that died at 7-8 days after dosing. Neither sarcocysts nor schizonts were found in chickens dosed with oocysts from a Masked Owl.     

Sarcocystis stenodactylicolubris n. sp., a new sarcosporidian coccidium with a snake-gecko heteroxenous life cycle

Oocysts/sporocysts of Sarcocystis sp. measuring 9.7 (9-10) x 7.6 (7-8) microns were found in the intestinal contents of the Dahl's whip snake Coluber najadum. Of wide spectrum of experimentally inoculated hosts, only species of the family Gekkonidae--Ptyodactylus guttatus and Stenodactylus grandiceps--were found to be susceptible intermediate hosts. Transparent, barely visible sarcocysts found in tail, limbs and tongue striated muscles of the geckoes were 175-200 microns x 35-50 microns in size at 78 DPI. Ultrastructurally, the primary cyst wall was characteristic by spine-like villar protrusions up to 800 nm long, 200-250 nm in diameter at their base, tapering to thinner apex. Protrusions appear typically lobular or irregular in the cross-sections. Back-transmission from P. guttatus to Coluber rogersi leaded to oocysts/sporocysts excretion since 38 days post infection. Based on sarcocyst morphology and experimental data, Sarcocystis stenodactylicolubris is apparently a new species. Based on obtained and already published results, Sarcosporidia parasitising colubrid snakes as definitive hosts are suggested to be family specific on the level of their intermediate host.     

Two new species of Sarcocystis (Apicomplexa: Sarcocystidae) infecting the wolverine (Gulo gulo) from Nunavut, Canada

Infection with Sarcocystis species is common in many species of animals, but it has not yet been reported in wolverines (Gulo gulo). Histological sections of tongues from 41 wolverines in the Kitikmeot Region, Nunavut, Canada, were examined for sarcocysts. Sarcocysts were found in 33 (80.4%) wolverines. Two structurally distinct types of sarcocysts were found. Type A sarcocysts were thin (<1 μm thick) walled. Ultrastructurally, the parasitophorous vacuolar membrane (Pvm) had minute undulations, but it lacked villar protrusions and was not invaginated into the granular layer. The bradyzoites were slender, about 5 × 1 μm in size. Structurally, these sarcocysts were distinct from known species of Sarcocystis and possessed a novel 18S and ITS-1 sequence, sharing 98% and 78% sequence similarity with Sarcocystis canis . A new species name, Sarcocystis kalvikus, is proposed for type A sarcocysts. In contrast, type B sarcocysts had relatively thicker (about 2 μm) cyst walls and larger bradyzoites, each about 10 × 2-3 μm. Ultrastructurally, the Pvm on the sarcocyst wall had villar protrusions that were either mushroom-like or sloping. Molecular analysis identified a unique 18S and ITS-1 sequence that placed them in a clade within the Sarcocystidae. Based on histology, TEM, and genetic data, the new name, Sarcocystis kitikmeotensis, is proposed. Sarcocystis kalvikus was found in 14 (34.1%), S. kitikmeotensis was found in 7 (17%), and both species were found in 12 (29.2%) of 41 wolverines.     

Sarcocystis infections among snakes in Israel

Natural infection with Sarcocystis has been recovered from 11 species of snakes from Israel and the adjacent territories (Cisjordan), infection was most abundant in subadults. Sporocyst dimensions obtained from the different snakes overlapped in size, but even in a same host species formed distinct size cohorts clustering either around 8.5 x 6.5 microns and 11.0 x 8.5 microns or around 11.0 x 8.5 microns and 12 x 10 microns. Sporocyst-size distribution was, however, altered following cross infections or in consecutively emitted feces. The largest cohort size conformed with the sporocyst dimensions of S. murivipera Matuscka, Heydorn, Mehlhorn, Abd-Al-Az, Diesing, Bichler 1987, described from Vipera palaestinae, one of the snake species included in the present study. Among infected snakes were rodent predators but also species feeding on smaller prey (reptiles). Sporocysts from eight of these species including some small-prey feeders, were available for infecting rodents, all, like S. murivipera, developed into sarcocysts in laboratory white mice (Mus musculus), but in none of the inoculated rodents from other genera, or reptiles. Sarcocysts found in free-ranging house mice infected V. palaestinae. Despite of an apparent conspecificity, Sarcocystis from the different snake species demonstrated a pronounced variation in their virulence to mice. Primary wall was identical in all ultrastructurally studied sarcocysts found in both house mice and laboratory mice fed on sporocysts from the diverse snake species.     

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.     

Sarcocystis in muscles of raccoons (Procyon lotor L.)

Sarcocysts of Sarcocystis sp. were found in 26 (50%) of 52 raccoons (Procyon lotor) from Ohio, Pennsylvania, Florida, and Maryland. Although only 4 (7.7%) of 52 cardiac muscles specimens were found to contain sarcocysts, 25% to 36.5% of tongue, diaphragm, masseter muscle, and esophagus specimens were found infected. By light microscopy, sarcocyst walls were less than 3 micron thick and had no conspicuous projections; interior septa were indistinct. By transmission electron microscopy, sarcocyst walls had short (mean = 2.7 micron), villus-like protrusions; thin septa were seen within the sarcocysts. The raccoon may be an intermediate host for a Sarcocystis sp. that completes its life cycle in an unidentified, wild carnivore.     

Sarcocystis sigmodontis n. sp. from the cotton rat (Sigmodon hispidus)

Sarcocystis sarcocysts were found in 3 of 4 cotton rats (Sigmodon hispidus) from Atlanta, Georgia. Sarcocysts were several centimetres long and were present only in skeletal muscles. The sarcocyst wall appeared thin (less than 1 micron), with minute projections in the light microscope. By transmission electron microscopy, the sarcocyst wall had 0.6-1.0 x 0.21-0.36-micron villar protrusions without microtubules. The metrocytes were 6.5 x 3.8 micron, and the bradyzoites were 8 x 2.7 micron. The sarcocysts were not infectious for dogs and cats. The parasite was named Sarcocystis sigmodontis because it differed from all sarcocysts in rodents.