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PubMed1994

Response of Ig-positive cells to Goussia carpelli (Protozoa: Apicomplexa) infections in carp (Cyprinus carpio L.).

The kinetics of Ig-positive cell populations in carp tissues was followed during an infection with the gut dwelling coccidian Goussia carpelli Léger et Stankovich, 1921. In cell suspensions of the anterior and posterior sections of the intestine, the proportion of Ig-positive cells increased with the development of the coccidia and peaked during oocyst formation at day 15 post exposure. These results suggest a reaction of the local mucosal immune system. In cell suspensions of pronephros the proportion of Ig-positive cells increased as well, indicating that a systemic immune response was also induced against this intestinal coccidian parasite of carp.

Animals↗
PubMed1994

The wisent (Bison bonasus, Bovidae) as an intermediate host of three Sarcocystis species (Apicomplexa: Sarcocystidae) of cattle.

Sarocysts were found in muscle tissue of a wisent (Bison bonasus) which was born and kept in Germany. Light microscopic and TEM examination revealed all the three named species known from cattle: Sarcocystis cruzi ("thin-walled", with longer hair-like villar protrusions of the primary cyst wall); S. hirsuta ("thick-walled", with tongue-like protrusions of the cyst wall arising with very short and narrow stalklets from the surface of the cyst and containing rows of electron-dense granules in the core); and S. hominis ("thick-walled", with finger-like protrusions of the cyst wall not constricted at their base and containing few or no electron-dense granules). So far, only S. cruzi was known to occur in Bison bison in North America. The findings in the wisent strikingly support a modified conception of the intermediate host specificity in Bovinae. In this connection the identity of S. cruzi and S. poephagicanis is suggested as well as that of S. hirsuta and S. poephagi.

Animals↗
PubMed1994

Experimental infection of elaphid snakes with Cryptosporidium serpentis (Apicomplexa: Cryptosporidiidae).

The shedding pattern of fecal Cryptosporidium serpentis oocysts, histopathologic changes in the gastric region, and the effect of spiramycin treatment were investigated in 6 experimentally infected, captive black rat (Elaphe obsoleta obsoleta), 4 yellow rat (Elaphe obsoleta quadrivittata), and 2 corn snakes (Elaphe guttata guttata). Feces were monitored for up to 2 years postinfection (PI). No significant (P > 0.07) differences were observed between expected and observed numbers of PI oocyst-positive feces. Two of 5 control animals acquired natural infections of C. serpentis over the period of study. No morphological differences were observed between oocysts from experimental and natural infections. Clinical signs included postprandial regurgitation in 5 of 13 (38%) snakes, not coinciding with the shedding of fecal oocysts. Midbody swelling and self-cure were not observed. Spiramycin treatment of 4 of 12 experimentally infected animals resulted in negative fecal examinations in 2 snakes and reduced the percentage of oocyst-positive feces in 2 other snakes from 75.5% to 24.5% and from 83.9% to 33.6%. Biopsies and necropsies revealed stages of Cryptosporidium in the gastric mucosa of all spiramycin-treated animals. The gastric mucosa was thickened and edematous, with focal necrosis, mucosal petechiae, and brush hemorrhages. Fibroplasia of lamina propria associated with chronic mucosal inflammation were common. Examination of direct fecal smears was found not to be a reliable technique for diagnosis of cryptosporidial infections in snakes.

Analysis of Variance↗
PubMed1994

A new coccidian parasite (Apicomplexa: Eimeriidae) from humans.

A new coccidian parasite has been found in stool specimens of humans with and without diarrhea. The oocyst of this parasite measures 8.6 microns in diameter (7.7-9.9 microns), with ovoid sporocysts 4.0 x 6.3 (3.3-4.4 x 5.5-7.1) microns. Each oocyst has 2 sporocysts and each sporocyst contains 2 sporozoites. Based on these characteristics and the structures observed by electron microscopy, this parasite has been classified in the genus Cyclospora. We propose the name Cyclospora cayetanensis n. sp. for this new human parasite.

Animals↗
PubMed1993

[The black-headed gull (Larus ridibundus L.), a new host for Cryptosporidium baileyi (Apicomplexa: Cryptosporidiidae)].

Black-headed full (L. ridibundus L.) represents a new host of C. baileyi Current, Upton and Haynes, 1986. In 1991-1992 during the months of May-July six localities in three regions of the Czech Republic were studied by examining in total 264 not flying gull chicks (4-30 days of age), applying the methods after Pavlásek (1987a, b, 1991). Cryptosporidia were found in gulls in all localities and spontaneous infection during the period under study occurred in 27.5-100% of birds (Tab. II, Fig. 1). The size of oocysts was 6.2-6.4 by 4.8-5.8 microns with means of 6.4 by 4.9 microns. The oocyst index (width/length) was 0.75-0.93 with means of 0.77. C. baileyi infection was demonstrated in 22 out of 24 dead gull chicks submitted to autopsy. From two localities total 15 gulls were killed, the examination of which revealed oocyst occurring in masses in the fluid from cloacal washes. Asexual and sexual endogenous developmental stages, including C. baileyi oocysts, in all birds undergoing autopsy were localized in caudal part of colon (1-2 cm from opening into cloaca) and in the cloaca. Findings of cryptosporidia were very frequent, above all, in the bursa Fabricii. In two dead and six with snoring disease, subsequently killed gull chicks, respiratory form of infection was demonstrated with simultaneous proof of endogenous developmental stages including oocysts in smears of mucous epithelium of sinus infraorbitalis, larynx, trachea and bronchi using the Giemsa stain after fixation with absolute methanol. An experimental transmission of infection by isolates of C. baileyi oocysts from gulls to five 4-day chicks (Gallus gallus f. domestica) using the dosis of 5 x 10(5) oocysts/chick was successful. The prepatent period lasted 4 days. On day 3 and 6 after infection two chicks died. The developmental stages of the protozoon were found in the lower part of colon, in cloaca and in bursa Fabricii. In chicks dead on day 6 after infection asexual stages of cryptosporidia were found in trachea and in bronchi. One chick survived the infection and excretion of oocyst (patent period) lasted 14 days. In this bird cloacal, bursal as well as respiratory form of C. baileyi infection was found. Control chicks were negative during the observation of 30 days. Oocysts from gulls do not lose their viability even after 8-month storage in the 2.5% solution of K2Cr2O7 at the temperature of 4 degrees C.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1993

Eimerian guilds (Apicomplexa: Eimeriidae) in Richardson's (Spermophilus richardsonii) and Wyoming (Spermophilus elegans) ground squirrels.

Feces of Richardson's ground squirrels (Spermophilus richardsonii) were examined to determine occurrence and prevalence of eimerian species and to compare guilds in these hosts to previously described guilds from Wyoming ground squirrels (Spermophilus elegans). Six species of Eimeria were collected from 100 Richardson's ground squirrels: Eimeria beecheyi (36% infected); Eimeria bilamellata (13%); Eimeria callospermophili-Eimeria morainensis complex (41%); Eimeria lateralis (6%); and Eimeria spermophili (9%). The species composition and prevalences were essentially identical in the 2 congeneric hosts. Three species were consistently more (> 30%) and 3 were consistently less (< 20%) prevalent in both host species. Furthermore, in both squirrel species the rare species were more prevalent in juveniles. Eimerian guilds such as these may be common to many species of ground-dwelling sciurid squirrels. The report of E. beecheyi in Richardson's ground squirrel constitutes a new host record for this species.

Age Factors↗
PubMed1993

A coccidian (Apicomplexa: Eimeriidae) with extracytoplasmally located stages in the kidney tubules of golden carp (Carassius auratus gibelio L.) (Cyprinidae).

Numerous coccidian stages were found in the kidney tubules of the golden carp (Carassius auratus gibelio). The merogonial and gamogonial stages were localized extracytoplasmally in the microvillous region of the epithelial cells. The host-parasite interface consisted of i) a large area where the parasite was separated from the host cytoplasm by the parasitophorous vacuole membrane only, and ii) a zone of multiple fusions of the host cell membrane investing the parasite to the neighbouring microvilli. The taxonomic status of the extracytoplasmic stages is not clear, however, their possible appurtenance to Eimeria scardinii, which was frequently found in the kidneys of golden carps in the same population, is discussed.

Animals↗
PubMed1993

[The possible pathways of substance transport in the muscle cysts of 2 species of Sarcosporidia (Sarcocystis, Apicomplexa, Sporozoa)].

The present work is a sequel of our previous cytological investigations of the cyst-forming coccidia of the genus Sarcocystis (reported elsewhere), now performed on two species from different hosts: S. muris (mouse) and Sarcocystis sp. (water buffalo). Acid phosphatase is synthesized in the endoplasmic reticulum of cystic zoites, its activity being seen in particular in the microenemes. As was established earlier (Radchenko, 1991b), these organelles are extended regions of the smooth endoplasmic reticulum channels and are capable of separating from the latter to be aligned eventually along the pellicle of the parasite. Further on, micronemes are seen to attach to the inner membrane complex of the cystic zoites, so that the ductula of micronemes get into contact with the complex membranes. Just after this, the membranes are seen disassembled in the sites around this contact. The ductula of micronemes appear to be connected with the plasmalemma, i.e, the outer pellicle membrane, and protrusions of the plasmalemma appeared in the sites of these connections. Acid phosphatase (and presumably other substances contained in the micronemes) are poured into the plasmalemmal protrusions to form vesicles. In their turn, these vesicles are separated outside from the plasmalemma to move towards the sarcocyst subwall layer along the filamentous structures found in the septae of the sarcocyst ground substance. Then the membranes of the vesicles disappear, and phosphatase activity is observed in the cyst wall.

Acid Phosphatase↗
PubMed1993

Host specificity of Calyptospora funduli (Apicomplexa: Calyptosporidae) in atheriniform fishes.

Calyptospora funduli has a broad host specificity, infecting at least 7 natural and 10 additional experimental definitive hosts, all atheriniform fishes within 5 families, but most in the genus Fundulus. Barriers, apparently innate ones, prevent any development of C. funduli in perciform fishes but allow incomplete or abnormal development of the parasite in a few unnatural atheriniform hosts. In the freshwater species Fundulus olivaceus and Fundulus notti, these abnormalities consisted of asynchronous development, degeneration of the parasite in early stages of development, and the formation of numerous macrophage aggregates. Rivulus marmoratus has the ability to eliminate infections with a granulomatous inflammatory response. Additional barriers that limit natural infections of C. funduli in other hosts include feeding behavior, environmental conditions, and geographic isolation.

Animals↗
PubMed1993

Coccidia (Apicomplexa), genetic diversity, and environmental unpredictability of four chromosomal species of the subterranean superspecies Spalax ehrenbergi (mole-rat) in Israel.

Forty-five mole-rats, representing 4 chromosomal species (2n = 52, 54, 58, 60) of the superspecies Spalax ehrenbergi, were collected from 12 localities in Israel in 4 distinct climatic regions. Feces were examined for coccidian oocysts and 41 (91%) were infected; 26 (63%) had multiple infections of up to 5 coccidian species, 4 of which are described here as new species. Sporulated oocysts of Eimeria anzanensis n. sp. were ellipsoidal 18.3 x 12.5 microns (14-22 x 10-16) and had elongate-ovoidal sporocysts 7.3 x 4.9 microns (5-10 x 3-7); it occurred in 39 of 45 (87%) mole-rats, including all chromosomal species. Sporulated oocysts of Eimeria spalacensis n. sp. were ovoidal 23.4 x 18.3 microns (17-29 x 12-21) with ovoidal sporocysts 9.4 x 6.8 microns (6-12 x 4-10); it occurred in 7 of 45 (16%) mole-rats (2n = 54, 58, 60). Sporulated oocysts of Eimeria carmelensis n. sp. were subspheroidal to ellipsoidal 19.1 x 16.5 microns (14-25 x 11-20) and had sporocysts that were spheroidal to ellipsoidal 8.6 x 6.2 microns (6-13 x 4-8); it occurred in 5 of 45 (11%) mole-rats (2n = 58, 60). Sporulated oocysts of Isospora spalacensis n. sp. were ellipsoidal 14.6 x 11.0 microns (12-17 x 9-14) with ellipsoidal to ovoidal sporocysts 8.5 x 4.5 microns (7.5-11 x 4-7); it occurred in 5 of 45 (11%) mole-rats (2n = 58, 60). Twenty-five of 45 (56%) mole-rats (all 4 species) were infected with a previously described form, Eimeria elliptica Sayin, Dincer, and Meric, 1977.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1993

A new species of Eimeria (Apicomplexa) from Cordylus cataphractus (Sauria: Cordylidae), from South Africa.

Three armadillo girdled lizards, Cordylus cataphractus Boie, 1828, housed at the Dallas Zoo in Texas, USA but originally imported from Namaqualand, South Africa, were found to be passing oocysts of a previously undescribed species of eimerian. Oocysts of Eimeria murphyi sp. n. are cylindroidal, 44.1 x 21.3 (41.5-46.5 x 20.5-24) microns, with a shape index (length/width) of 2.07 (1.75-2.21). A micropyle and oocyst residuum are absent, but a polar granule is present. Sporocysts ellipsoidal, 13.5 x 10.2 (13-14.5 x 9.5-11) microns (N = 20), with a shape index of 1.32 (1.23-1.46). Each sporozoite possesses a single, posterior refractile body. This represents the first report of coccidia infecting a member of the saurian family Cordylidae.

Animals↗
PubMed1996

Population dynamics of two species of Eimeria (Apicomplexa: Eimeriidae) in deer mice (Peromyscus maniculatus): biotic and abiotic factors.

I investigated whether biotic factors (competitive exclusion between parasites and host immunity), abiotic factors (high temperature, low temperature, and rainfall), or a combination of the 2 affected the population dynamics of Eimeria arizonensis and Eimeria delicata in naturally infected deer mice (Peromyscus maniculatus). There was no evidence of competitive exclusion between E. arizonensis and E. delicata, nor were E. arizonensis population dynamics affected by host immunity (young deer mice were not infected significantly more frequently than adults). However, high temperatures were negatively associated with the prevalence of observed infections (r = -0.725, P < 0.001), suggesting sporulation of oocysts might be affected. In contrast, juvenile deer mice were infected with E. delicata more frequently than adults (z = 2.05, P < 0.02), suggesting that host immunity plays a role in the population dynamics of E. delicata. Temperature and rainfall during oocyst sporulation were not significantly associated with the prevalence of observed E. delicata infections. Finally, there was no evidence that a combination of biotic and abiotic factors was important in the population dynamics of either eimerian. Thus, the population dynamics of E. arizonensis seem to be controlled by abiotic factors, whereas those of E. delicata seem to be affected by biotic factors.

Age Factors↗
PubMed1996

The genus Hepatozoon (Apicomplexa: Adeleina).

Hemogregarines of the genus Hepatozoon are intraerythrocytic apicomplexan parasites that have been described from all groups of tetrapod vertebrates. Gametogenesis, fertilization, and sporogonic development, which culminates in the formation of polysporocystic oocysts, occur in the gut or hemocoel of a hematophagous arthropod definitive host. Merogonic development occurs in the internal organs of vertebrate hosts after they ingest these infected arthropods. The presence of cystic stages, observed for many Hepatozoon species, increases life cycle complexity and exploits the feeding behavior of vertebrate hosts. The inconsistency of morphological characteristics of these parasites, especially those associated with gamont structure, coupled with low host specificity of the parasites for their invertebrate and vertebrate hosts, have rendered species differentiation difficult. A systematic review of the hemogregarine complex has resulted in the expansion of the genus Hepatozoon to include all members of the genus Haemogregarina that infect amphibians, snakes, lizards, crocodilians, birds, and mammals.

Animals↗
PubMed1996

Coccidia of the collared peccary (Tayassu tajacu) in southern Texas with descriptions of three new species of Eimeria (Apicomplexa: Eimeriidae).

In February 1993, fresh fecal samples were collected from 47 collared peccaries (Tayassu tajacu) killed by hunters at the Chaparral Wildlife Management Area, southern Texas, USA. Five species of coccidia (Eimeria chaparralensis n. sp. [9/47, 19%], Eimeria dicotylensis n. sp. [21/47, 21%], Eimeria pecari n. sp. [2/47, 4%], Eimeria sp. [1/47, 2%], and Klossia sp. [1/47, 2%]) were observed. Measurements are in micron. Sporulated oocysts of E. chaparralensis are rough-walled, elongate ovoidal, 43.3 x 28.5 (37-52 x 26-35); sporocysts are elongate ellipsoidal 21.8 x 9.0 (16-27 x 7-12); micropyle (approximately 4.9), Stieda, and substieda body are present; sporocyst residuum is present in newly sporulated oocysts; polar granule and oocyst residuum are absent. Sporulated oocysts of E. dicotylensis are smooth-walled, ovoidal, 25.7 x 20.1 (23-29 x 17-23); sporocysts are ellipsoidal 13.0 x 6.9 (11-17 x 6-9); micropyle and oocyst residuum are absent; polar body sometimes present; Stieda body and sporocyst residuum always present. Sporulated oocysts of E. pecari are smooth-walled, elongate ellipsoidal, 26.8 x 18.1 (22-31 x 15-21); sporocysts are elongate ellipsoidal 16.4 x 5.9 (13-22 x 4-7); micropyle (approximately 5.8) with collar, Stieda body, substieda body, and sporocyst residuum are present; polar granule and small oocyst residuum sometimes present. There were no sex or age differences in prevalences of infection, and there were no positive or negative associations between any species of eimerian. The majority of hosts were infected with a single species of Eimeria. Overall prevalence of infection with eimerians was 23/47 (49%).

Animals↗
PubMedDate not supplied

[Sarcocystis phoeniconaii n. sp. Murata, 1986 (Apicomplexa: Sarcocystidae) of the lesser flamingo (Phoeniconaias mirror: Ciconiiformes)].

The tiny rice-grain like sarcocysts measure 3-5 x 1 mm, they are situated subfascially or in the depth of the muscles. The 50 nm thick irregular primary cyst wall forms towards the inside, small, bubble-like, less osmiophilic invaginations, which partly are concentrated in such a way, that a spongious like structure develops. The so surrounded protrusions are vertically or slightly inclined; they measure 4.25 x 1.7 microns and they are filled with compact fibrils. The cyst wall is underlaid by an average of 7.0 microns thick tape consisting of ground substance, from which an extensive septation runs to the center of the cyst. The so formed chambers are filled with lancet-like merozoites, which measure 15-20 x 1.8-2.5 microns. Their fine structure is identical with merozoites of all other sarcosporidia. A round vacuole, which is placed at the rear end of the merozoite near the nucleus seems to be a characteristic. Metrocytes are found rarely in the periphery and they are usually degenerated. In some cysts cystozoites, ground substance and protrusions show signs of lysis, the septation, however, remains usually unchanged.

Animals↗
PubMed1997

Eimeria spp. (Apicomplexa: Eimeriidae) from black- and white-tailed prairie dogs (Cynomys ludovicianus and Cynomys leucurus) in central and southeast Wyoming.

Feces collected from live-trapped black- (Cynomys ludovicianus) and white-tailed prairie dogs (Cynomys leucurus) from central and southeastern Wyoming were examined to determine the presence and prevalence of eimerian species. Six species (Eimeria adaensis [black-tailed prairie dog prevalence = 33%, white-tailed prairie dog prevalence = 51%], Eimeria beecheyi [8%, 28%], Eimeria callosper-mophili [64%, 71%], Eimeria lateralis [3%, 7%], Eimeria morainensis [19%, 8%], and Eimeria spermophili [2%, 1%]) were identified from both host species. Eimeria pseudospermophili was found infecting only black-tailed (prevalence = 1%) and Eimeria bilamellata only in white-tailed prairie dogs (2%). Reinfections in individual hosts were observed with E. callospermophili and E. adaensis. Comparison of these results with the published literature suggests that the host genera Cynomys and Spermophilus share a common guild of eimerians and that members of this guild have a long evolutionary association with these hosts, or host switching, or both, is common between these groups.

Animals↗
PubMed1997

Temperature modulation of the response of Ig-positive cells to Goussia carpelli (Protozoa: Apicomplexa) infections in carp, Cyprinus Carpio L.

The influence of temperature on the kinetics of immunoglobulin-positive (Ig+) leukocytes in cell suspensions prepared from the pronephros and the intestine of common carp Cyprinus carpio during the development of Goussia carpelli, a gut-dwelling coccidian parasite, was examined. The development of the parasite was temperature dependent. At 20 C, oocysts were formed 2-3 wk postexposure (PB), at 15 C for 3-4 wk PE, and at 12 C for 5-6 wk PE. At all 3 temperatures, changes of relative numbers of Ig+ cells were observed in cell suspensions. During merogony and gamogony, the proportion of Ig+ cells increased, peaked during oocyst formation of the parasite, and then remained elevated. Serum collected from infected carp 8-20 days PE contained immunoglobulins binding to G. carpelli merozoites. The development of the parasite and the increase of Ig+ cells in intestine and pronephros of infected carp were temperature dependent. The peak level of Ig+ cells appeared not to be influenced by temperature. These findings indicate that even at low temperatures local and systemic immune responses are induced in carp with enteritic parasite infection.

Animals↗
PubMed1997

Isospora tiaris n.sp. (Apicomplexa: Eimeriidae) from the sooty grassquit (Tiaris fuliginosa), a passeriform bird of South America.

Isospora tiaris n. sp. is described from the feces of an adult bird, a sooty grassquit (Tiaris fuliginosa) from Venezuela. The oocysts are subspherical, 27.1 x 23.8 (24.7-30.0 x 21.2-26.5) microns with a bilayered, smooth, colorless wall. A micropyle and oocyst residuum are absent; an ellipsoidal polar granule is usually present. Sporocysts are ovoidal, 14.7 x 10.8 (12.4-16.8 x 8.8-12.4) microns with prominent Stieda and substieda bodies and a residuum composed of small uniform granules.

Animals↗