Isospora elmahalensis n. sp. (Apicomplexa, Eimeriidae), a Parasite of the White-Cheeked Bulbul (Pycnonotus leucogenys) in Saudi Arabia

Isospora elmahalensis n. sp. is described from the Saudi Arabian bird, Pycnonotus leucogenys , from the Elmahala valley. Sporulated oocysts of I. elmahalensis were spherical or nearly subspherical, 19.5–22.5 × 18.5–20 (21.34 ± 0.4 × 19.06 ± 0.5) μm. Oocysts lacked a micropyle, residuum, and polar granule. Sporocysts were ovoid, 14–17.5 × 7–12 (16.08 ± 1.05 × 9.9 ± 1.55) μm, and had a Stieda body and sporocyst residuum, but lacked a substiedal body. Sporozoites were elongated with a clear globule at one end. The host bird belongs to the order Passeriformes.     

Isospora thibetana N. Sp. (Apicomplexa, Eimeriidae), a Parasite of the Tibetan Siskin (Serinus thibetanus=Carduelis thibetanus) (Passeriformes, Fringillidae)

Tibetan siskins are birds native to the Himalayan region often imported into Italy for commercial purposes. Fecal examination of 45 imported subjects with clinical signs of diarrhoea revealed the presence of a large number of coccidian oocysls. After sporulation, accomplished by mixing feces with 2.5 % (w/v) acqueous K₂Cr₂O₇ at room temperature (22° C ± 1° C), exogenous stages of an Isospora species were revealed. The oocysts of this Isospora are spherical, have a bilayered colorless wall, and average 23.24 μm × 23.05 μm; oocyst residuum and micropyle are absent, while an oval polar granule is rarely present. The elliptical sporocysts average 18.44 μm × 10.97 μm and the Stieda body protrudes slightly from the end of the sporocyst. A spherical sporocyst residuum is present though it sometimes consists of scattered granules. The spindle-shaped sporozoites average 11.53 μm × 2.86 μm, and have two refractile bodies. The taxonomic position of the tibetan siskin is controversial. Some authors include this species in the genus Serinus , while others include it in the genus Carduelis. The coccidian species isolated from these tibetan siskins was, for this reason. compared with the Isospora species previously described both in the genus Carduelis and in the genus Serinus. As a result of this comparison a new species. Isospora thibetana , was named. In the intestine of dead subjects, oocysts were found only in the ileum where the mucosa was greatly thickened and presented a heavy leucocytic infiltration consisting mainly of lympho-monocytic cells. A similar infiltration was observed in liver and lungs as well.     

Enzyme Variation of Eimeria arizonensis from Peromyscus truei and P. boylii

ABSTRACT. Cricetid rodents, Peromyscus truei and P. boylii , were inoculated with sporulated oocysts of Eimeria arizonensis collected from wild P. truei maintained in the lab. In P. truei the prepatent period was 4–5 days, the patent period was 9–11 days, and sporulated oocysts were 21.5 × 25.0 (20–23 × 24–26) μm with sporocysts 7.7 × 12.0 (6–8 × 10–13) pm. In P. boylii the prepatent period was 6–7 days, the patent period was 8–9 days, and sporulated oocysts were 20.1 × 23.2 (18–22 × 21–24) pm with sporocysts 6.8 × 10.0 (5–8 × 9–12) pm. Sporulated oocysts from both host species were used in direct side-by-side comparison of isozyme banding patterns using protein electrophoresis. The parasite has polytypic loci for leucine aminopeptidase (LAP), lactate dehydrogenase (LDH), and 6-phosphogluconate dehydrogenase (6-PGD). In oocysts from P. truei , LAP showed one band with fast migration and LDH and 6-PGD each showed two bands, one with fast and one with slow migration. In oocysts from P. boylii , LAP and LDH each had one band with slow migration and 6-PGD had one band with moderate migration. Oocysts of E. arizonensis collected from P. boylii were used to inoculate P. truei. The prepatent and patent periods, structural measurements, and isozyrne banding patterns of the resultant oocysts were the same as those from P. truei when inoculated with oocysts from P. truei.     

Coccidia of Brazilian Mammals: Eimeria Marajoensis N. Sp. (Apicomplexa: Eimeriidae) From the Anteater, Tamandua Tetradactyla (Xenarthra: Myrmecophagidae)

ABSTRACT Feces from a juvenile specimen of the anteater Tamandua tetradactyla from Ponta de Pedras, Marajó, Pará, northern Brazil, contained three different coccidial oocysts: Eimeria tamanduae Lainson, 1968; E. corticulata Lainson & Shaw, 1990; and a third species previously unrecorded and described here as Eimeria marajoensis n. sp. Oocysts of the latter parasite are spherical to subspherical, 13.9 ± 1.5 times 13.4 ± 1.4 (11.1-16.5 times 11.1-16.5) μm, shape index (length/width) 1.0 (1.0-1.2). the oocyst wall is a single, Colorless layer about 0.6-1.0 μm thick with no striations or micropyle. There is no oocyst residuum, but a single, round, oval or irregularly shaped polar granule of about 0.75-2.5 μm is consistently present. the sporocysts are broadly ellipsoidal, 7.1 ± 0.7 ± 5.3 ± 0.6 (6.0-8.8 times 4.0-5.7) μm, shape index 1.3 (1.2-1.5), with a delicate wall bearing a minute stieda body. No sub-stieda body was visible. the sporocyst residuum consists of some 10-20 rounded granules, lying between the two slightly curved sporozoites which measure approximately 6.5 times 2.0 μm. Sporocyst refractile bodies were not discernablc.     

Coccidia (Eimeria tachyglossi n. sp., E. echidnae n. sp., and Octosporella hystrix n. sp.) in the Echidna, Tachyglossus aculeatus (Monotremata: Tachyglossidae)

Oocysts of Octosporella hystrix n. sp., Eimeria tachyglossi n. sp., and E. echidnae n. sp. are described from the feces of the echidna Tachyglossus aculeatus (Monotremata: Tachyglossidae) from Australia. Eimeria tachyglossi has subspherical oocysts, 26.4 × 23.7 μm in size, with a single oocyst wall; no micropyle; four ellipsoidal sporocysts 13.2 × 9.7, slightly pointed at one end, each containing two sporozoites. Eimeria echidnae has subspherical oocysts, 19.4 × 17.8 in size, with a single oocyst wall; no micropyle; four ellipsoidal sporocysts 9.8 × 7.8, blunt at both ends, each containing two sporozoites. Octosporella hystrix has ovoid or subspherical oocysts 32.9 × 29.7 in size with a thick outer and thin inner oocyst wall; no micropyle; eight sporocysts spherical or slightly subspherical 11.3 × 11.2 each containing two sporozoites lying in embrace, with an extensive granular sporocyst residuum about the equator of the sporocyst. Endogenous stages considered to be of E. tachyglossi at least, were recognized in the lamina propria and epithelium on villi in the small intestine of three echidnas.     

Description of the Oocysts of Two New Species of Eimeria (Apicomplexa: Eimerüdae) from the Florida Manatee, Trichechus manatus (Sirenia: Trichechidae)

Two new species of Eimeria (Apicomplexa: Eimerüdae) are described from the feces of the Florida manatee, Trichechus manatus latirostrts (Sirenia: Trichechidae). Oocysts of Eimeria manatus n. sp. are spherical to subsphencal, 11.8 × 10.7 (10.5–13.5 × 9.0–13.5) μ m , with a smooth, thin, bilayered wall; shape index (length/width) 1.1 (1.0–1.3). Micropyle and oocyst residuum absent; polar granule(s) usually present. Sporocysts are ovoid, 8.6 × 5.1 (8.0–9.5 × 5.0–5.5) μm, with thin, membrane–like walls and a knoblike Stieda body; shape index 1.7 (1.4–1.8). Sporozoites elongate, each with a large posterior refractile body. The sporocyst residuum consists of a small cluster or row of few to many small granules. Oocysts of Eimeria nodulosa n. sp. are spherical to subspherical, 15.6 × 14.7 (14.5–17.5 × 13.0–16.0) μm, with a distinctly bilayered wall; shape index 1.1 (1.0–1.2). Unsporulated and freshly sporulated oocysts often possess large, knob–like structures on the external surface of the oocyst wall that support a thin membrane or filament. Micropyle, oocyst residuum and polar granule absent. Sporocysts are ovoid, 10.6 × 5.9 (9.5–12.0 × 5.0–6.5) μm, with a smooth, thin wall and knob–like Stieda body; shape index 1.8 (1.5–2.1). Sporozoites granular and elongate, each with a large posterior refractile body. The sporocyst residuum consists of a loose aggregate or scattered mass of moderately sized granules.     

Eimeria galateai sp. n. from the Paradise Kingfisher, and Eimeria duncani sp. n. from the Sacred Kingfisher in Papua New Guinea

SYNOPSIS. Eimeria galateai sp. n. from the paradise kingfisher ( Tanysiptera galatea Gray) and Eimeria duncani sp. n. from the sacred kingfisher ( Halcyon sancta Vigors & Horsfield) have been described from Papua New Guinea. Four of 11 paradise kingfishers were infected with E. galateai oocysts, measuring 13 (11–16) × 9 (8–11) μm. The oocysts were ovoid with nipple-like protrusion at one pole. Micropyle and polar granule were absent, while oocyst residuum (5 × 4 μm) was present. Sporocysts, measuring 5 (4–6) × 2 μm, were elongate-ovoid, and had a distinct convex Stieda body; the sporocyst residuum was absent. Two of 9 sacred kingfishers were infected with ovoid-truncated, 22 (19–25) × 16 (12–18) μm oocysts of E. duncani . Polar granule (5 × 2) was present in the oocysts, but there was no micropyle or oocyst residuum. Sporocysts were ovoid, measuring 9 (8–10) × 5 (4–6) μm, with a prominent Stieda body, and granular sporocyst residuum. Eimeria galateai and E. duncani are the first species of this genus to be described from birds of the order Coraciiformes.     

Isospora gallicolumbae sp. n. from Beccari's Ground Dove (Gallicolumba beccarii Salvadori) in Papua New Guinea

SYNOPSIS. Isopora gallicolumbae sp. n. is described from Beccari's ground dove, Gallicolumba beccarii Salvadori, in Papua New Guinea. The ellipsoidal oocysts average 16.0 × 20.0 μm. The oocyst wall is light green, single-layered (∼ 0.8 μm), and becomes distorted within 10 min in sugar solution. Micropyle and oocyst residuum are absent; one polar granule is present. Sporocysts are ovoid, 8.0 × 12.0 μm. with prominent conical Stieda body. Sporocyst residuum is a spherical mass (∼ 5.0 μm) of lighter and darker granules. This is the first species of Isospora reported from a host in the avian order Columbiformes.     

Eimeria (Protozoa: Eimeriidae) of the Cottontail Rabbit Sylvilagus audubonii in Northeastern Colorado, with Descriptions of Three New Species

SYNOPSIS. All of 100 cottontail rabbits Sylvilagus audubonii were found to be infected with 1-6 species of Eimeria. Three new species, E. audubonii, E. neoirresidua and E. poudrei are described from this host. Sub-spherical oocysts of E. audubonii average 21.2 by 17.1 μ; polar body, micropyle, oocyst residuum and sporocyst residuum are all absent; ellipsoidal sporocysts average 12.9 by 5.8 μ. Ovoid to ellipsoidal oocysts of E. neoirresidua average 25.7 by 17.9 μ; polar body and oocyst residuum are absent; micropyle and sporocyst residuum are present; ellipsoidal sporocysts average 14.5 by 6.4 μ. Ovoid to ellipsoidal oocysts of E. poudrei average 26.0 by 18.1 μ; polar body is lacking; micropyle, oocyst residuum and sporocyst residuum are present; ellipsoidal sporocysts average 14.4 by 6.4 μ. Three species of Eimeria previously described in the literature, E. maior Honess, 1939, E. media form honessi Carvalho, 1943 and E. environ Honess, 1939 are redescribed. A detailed structural and statistical analysis of each species is presented with at least 200 sporulated oocysts measured in each instance. A host list and a key to the Eimeria of cottontails is given. The use of detailed studies of oocyst size and structure as a tool for specific diagnosis of the Eimeria of cottontails is discussed.     

Eimeria ornata N. Sp. (Apicomplexa: Eimeriidae) from the Ornate Box Turtle, Terrapene ornata ornata (Reptilia: Testudines), in Texas

Eimeria ornata n. sp. is described from the feces of 6/16 (37.5%) ornate box turtles, Terrapene ornata ornata , in northcentral Texas. Endogenously sporulated oocysts are ellipsoid 17.9 × 15.7(16-21 × 14-18) μm, with a thin, single-layered wall; shape index 1.14 (1.0-1.3). A micropyle is absent but a polar granule was present in one third of the oocysts. An oocyst residuum was present, consisting of numerous small globules situated either in a distinct mass or scattered within the oocyst. The sporocysts are elongate, 11.1 × 5.4 (9-13 × 5-6) μm, with an indistinct Stieda body at 1 pole. A sporocyst residuum is present, consisting either as a compact mass or as scattered granules. The sporozoites are elongate, 9.5 × 2.0 (8-12 × 2) μm, in situ, with spherical anterior and posterior refractile bodies. The new species is distinguished from the similar Eimeria carri Ernst & Forrester, 1973, from eastern box turtles, T. Carolina , by slight differences in oocyst morphology and endogenous sporulation.     

Eimeria ovata n. sp. and Other Coccidia of the Eastern Chipmunk Tamias striatus in Massachusetts

SYNOPSIS. Eimeria vilasi, E. wisconsinensis , and E. ovata n. sp. were found in the intestinal contents of eastern chipmunks Tamias striatus in Massachusetts. The oocysts of E. ovata are ovoid with mean dimensions of 26.1 × 16.7 μ. The outer oocyst wall is rough, with small pits. Micropyle and oocyst residuum are absent. Sporulation time at room temperature is 7–8 days.     

Eimeria procyonis sp. n., an Isospora sp., and a Redescription of E. nuttalli Yakimoff and Matikaschwili, 1932 (Protozoa: Eimeriidae) from the American Raccoon (Procyon lotor)

SYNOPSIS. Thirty-two of 48 raccoons examined were infected with a previously undescribed species of Eimeria which is herein named E. procyonis. Of the 32 infected animals, 10 also harbored E. nuttalli and 1 had Isospora sp. oocysts.
The ellipsoid to ovoid oocysts of E. procyonis measured 23.4 × 18.0 (16–29 × 13–24) μm; its sporocysts measured 12.1 × 9.3 (11.5–15 × 7–10) μm, each containing a slightly flattened substiedal body. The sporocyst residuum consisted of numerous scattered granules each ∼1 μm in diameter. The oocyst wall was double-layered. The outer layer appeared rough and pitted, measuring 1.5 μm, except at the micropyle where it was 1 μm thick.
The oocysts of the Isospora sp. measured 16.8 × 13.7 (16–18.5 × 12.5–15.5) μm. The wall consisted of a single layer ∼0.5 μm thick. The sporocysts measured 11.2 × 9.1 (9.5–11.5 × 8–10) μm, and each contained 4 elongate sporozoites. The oocysts of E. nuttalli measured 17.5 × 13.6 (12-21 × 11-15) μm, with a smooth single-layered wall approximately 0.7 μm thick. The sporocysts measured 12.2 × 7.1 (9-13 × 5.5–11) μm. Each sporocyst had a thin, dark, Stieda body and the sporocyst residuum consisted of many fine granules.     

Isospora petrochelidon sp. n. (Protozoa: Eimeriidae) from the Cliff Swallow, Petrochelidon pyrrhonota

SYNOPSIS. Isospora petrochelidon sp. n. (Protozoa: Eimeriidae) is described from the cliff swallow, Petrochelidon pyrrhonota , from Douglas County, Colorado. Oocysts were passed primarily between 4 and 9 p.m. Sporogony was completed by 24 hr in 3% aqueous potassium dichromate at 21–28 C. The ellipsoid to ovoid oocysts averaged 25.2 × 22.2 μm. The oocyst wall was smooth, colorless, and single-layered. The 2 polar granules were disc-shaped, each adjoining a sporocyst. The lemon-shaped sporocysts averaged 18.4 × 10.8 μm. There was no membrane enclosing the sporocyst residuum and sporozoites. Two fledgling Isospora -free swallows fed sporulated oocysts began passing them on day 4 and died with massive infections on day 5. Data from these birds indicate that schizogony occurred during nighttime hours, gametogony during the day. Endogeny was found throughout the intestine distal to the gizzard, with schizogony confined to the convoluted glands of the subvillar mucosa and gametogony to the villar epithelium. Sporocysts released from mechanically ruptured oocysts excysted in 2% pancreatin within 5 min. Sporulated oocysts fed to a pigeon squab, duckling and cockerel produced no infections.     

Infection kinetics and developmental biology of Cryptosporidium muris (strain MCR) in Korean native kids and Corriedale lambs

A total of nine Korean native kids and two Corriedale lambs, 1-20 days old, were each inoculated per os with a single dose of 2 × 10⁷ oocysts of Cryptosporidium muris (strain MCR) originated from mice to elucidate the kinetics and developmental stages of the coccidium in small ruminants. Irrespective of host''s age, the prepatent period for both animals ranged from 19 to 35 days (28.1 days, on the average) and the patent period 16-85 days (47.8 days), and the total oocyst outputs showed enormous differences. Infection with greater numbers of oocyst outputs was not ordinarily established by transmission experiments. Oocysts discharged from the kids retained their infectivity by the mouse titration method. The immunogenicity of the coccidium and oocyst reproduction were proven by challenge infection and administration of prednisolone acetate, respectively. All the developmental stages of the coccidium in parasitophorous vacuoles were found by transmission electron microscopy in the pits of the gastric glands of a kid inoculated with oocysts and then necropsied on day 44 postinoculation. It indicated the full course of the host-parasite relationship in kids and lambs as well as mice.     

On the Taxonomic Status of the Family Pfeifferinellidae (Coccidia), with a Description of Pfeifferinella gugleri sp. n.

SYNOPSIS. Pfeifferinella gugleri sp. n. was found in the liver of each of 2 land snails, Triodopsis albolabris (Say), in Iowa. The stages found, their average length × width dimensions (in μm), and their principal features were as follows: oocysts (21 × 14.5) ovoid, with micropyle and oocyst residuum; meronts (20 × 15) with 24–32 merozoites: microgametocytes (15 × 11.5) with many small microgametes; macrogametes (20 × 10.5) with 1–5 nucleoli and 1–2 wall-forming bodies, but without a "vaginal [fertilization] tube." This tube, originally described by Léger & Hollande, 1912, from Pfeifferinella impudica , has since been considered a principal taxonomic feature of the family Pfeifferinellidae. In the absence of this structure, the taxonomic status of this monogeneric family is reexamined with the recommendation that the family be retained as distinct, but redefined to exclude the "vaginal tube" as a valid characteristic. The discovery of P. gugleri brings to 3 the number of pfeifferinellids reported, the other 2 being P. impudica Léger & Hollande, 1912, and P. ellipsoides Wasielewski, 1904, all from gastropods.     

Plasmodium cynomolgi: the comparative infectiousness of individual rhesus monkeys

Five rhesus monkeys were infected with the malaria parasite Plasmodium cynomolgi Mayer. Anopheles stephensi Liston mosquitoes were fed on each monkey over the period of prepremunitive gametocytemia. Individual monkeys did not differ significantly in either mean daily gametocyte count (median = 1300 gametocytes per mosquito blood meal volume per day) or mean daily oocyst production (median = 34 oocysts per mosquito per day). Significant differences among monkeys in daily oocyst/gametocyte conversion ratio were attributable to essentially random correlation effects. The observed range in duration of the period of prepremunitive gametocytemia was 14–43 days. Total oocyst production over this period, as calculated for a unit mosquito biting rate of one per day, ranged from 130 to 2800 oocysts. The overall efficiency of conversion of gametocytes to oocysts in A. stephensi was estimated at 0.02 oocysts per gametocyte.     

Eimeria zapi sp. n. from the Meadow Jumping Mouse, Zapus hudsonius Zimmerman in Southwestern Michigan

SYNOPSIS Four of 5 meadow jumping mice ( Zapus hudsonius ) captured had in their feces a previously undescribed species of Eimeria which is named Eimeria zapi sp. n. The sporulated oocysts measured 21.7 (19.5–24.0) × 20.3 (17.5–23.0) μm. The single-layered oocyst wall was 1.5 μm thick, rough, pitted and appeared clear-to-amber. Usually 2 polar granules could be seen. An oocyst residuum was not observed. Each sporocyst averaged 16.0 (12.5–18.0) × 9.7 (7.5–11.5) μm. A substiedal body was present. The sporocyst residuum consisted of a membrane-enclosed packet of 15 to 20 granules. This is the first species of Eimeria to be described from the genus Zapus.     

The Structure of the Oocyst and the Excystation Process of Isospora marquardti sp. n. from the Colorado pika, Ochotona princeps

SYNOPSIS. Oocysts of Isospora marquardti sp. n. from the Colorado pika, Ochotona princeps , have spheroid oocysts, 30.5 (23–36) μm in diameter, and ovoid sporocysts, measuring 19.3 × 12.0 (17–22 × 10–14) μm. A polar body, 2 × 4 μm, a spheroid sporocyst residuum (8.3 μm in diameter), a Stieda body, and a distinct substiedal body (3 × 3 μm) are present. A micropyle and an oocyst residuum are absent. Excysted sporozoites, averaging 3.0 × 18.5 (2–4 × 15–20) μm, contain 2 refractile globules, 1 on each side of the nucleus with a prominent nucleolus.
The sporozoite excystation process using a trypsin-sodium taurocholate fluid is described.     

Isolation and identification of Cryptosporidium from various animals in Korea. III. Identification of Cryptosporidium baileyi from Korean chicken]

Each of SPF chicken (Hi-Line strain, 2-day-old males) was inoculated with 2.5 or 5 x 10(4) oocysts by stomach tube. The oocyst was the medium type of Cryptosporidium previously isolated from Korean chicken origin, and passed in 2-day-old SPF chicken. The patterns of oocyst discharge were monitored daily, and in order to observe the ultrastructure of the developmental stages, the bursa of Fabricius of the chicken was examined by transmission electron microscopy (TEM) on the 12th day postinoculation. The prepatent period for 8 chicken was 5.9 days postinoculation on the average, and the patent period was 12.9 days. The number of oocysts discharged per day for the chicken was reached peak on day 12 postinoculation on the average. A large number of oocysts was found in fecal samples obtained from inoculated chicken on days 8-14 postinoculation. The ultrastructural feature of almost every developmental stage of the medium type from chicken was very similar to that of Cryptosporidium previously isolated from mammalia including human and birds except for the attachment site of C. muris to the mucus cell from mammalia, but dimension of the oocysts from fecal samples of the medium type was different from those of C. meleagridis and mammalia origin. The above results reveal that the medium type of Cryptosporidium of Korean chicken origin is identified as Cryptosporidium baileyi.     

Development of patent infection in immunosuppressed C57Bl/6 mice with a single Cryptosporidium meleagridis oocyst

The ability of Cryptosporidium meleagridis to produce patent infection was studied in adult C57BL/6 mice that were immunosuppressed with dexamethasone phosphate provided in the drinking water at a dosage of 16 microg/ml. Four days after the onset of immunosuppression, mice were orally challenged with 1, 3, 10, or 1,000 C. meleagridis TU1867 oocysts per mouse. The mice were monitored daily for 18 days postinoculation for oocyst shedding. Five of 10 mice given a single oocyst, 4 of 5 mice given 3 oocysts, and all 9 mice given either 10 or 1,000 oocysts became infected and began shedding oocysts 5-7 days after challenge and continued to shed oocysts until the end of the experiment on day 18 postchallenge. Approximately 10(7) oocysts per mouse per day were excreted, regardless of the challenge dose. Neither the noninfected, immunosuppressed nor the inoculated, nonimmunosuppressed control mice shed oocysts. The excreted oocysts were confirmed to be those of C. meleagridis by polymerase chain reaction-restriction fragment length polymorphism analysis. We show that C. meleagridis, originally classified as an avian pathogen but recently found in humans with cryptosporidiosis, can produce patent infection in mice infected with a single oocyst. Moreover, we demonstrate that the immunosuppressed C57BL/6 adult mouse is an ideal host for the propagation of clonal populations of C. meleagridis isolates for laboratory studies.