The Life Cycle of Eimeria bateri (Protozoa, Eimeriidae) in the Japanese Quail Coturnix coturnix japonicum

SYNOPSIS. Eimeria bateri, a parasite of the Indian quail, was described from laboratory infections in Japanese quail. First generation schizonts developed in the glands of the duodenum and upper intestine. Second, 3rd and 4th generation schizonts and gametocytes occurred in the villous epithelium. There was a gradual spread along the small intestine until the whole organ was affected. The prepatent period was 4 days and the patent period 6 days. Graded doses from 5,000 to 1,280,000 oocysts produced very little pathogenic effect in young quail. E. bateri did not infect young pheasants or chicks.     

The species of Eimeria in rabbits for meat production in Britain

Eight species of coccidia were recognized in 596 faeces samples from 3 commercial rabbitries in South East England. The level of infection was related to management methods and at one site it was reduced by an outbreak of mucoid enteritis and/or its treatment with oxytetracycline. In samples from rabbits managed conventionally in the wire cages over droppings-pits, 96% contained oocysts and of these, 60% had 1000-10000 oocysts/g. Mixed infections were common, 67% of the animals carrying 2-4 different species. Eimeria, media, E. magna and E. perforans occurred most frequently; E. coecicola, E. irresidua and E. flavescens were less common and E. intestinalis and E. piriformis were relatively rare. E. stiedai was not recorded.     

Schizonts and Microgametocytes of Eimeria auburnensis Christensen and Porter, 1939, in Calves

SYNOPSIS. Schizonts were found in the middle and lower third of the small intestine of two calves killed 12 and 14 days after they had been inoculated with pure cultures of oocysts of Eimeria auburnensis. The schizonts ranged from 78 to 250 μ long by 78 to 150 μ wide (mean 92 by 139.9 μ). They were usually located deep in the lamina propria near the muscularis mucosae instead of in the villi where most schizonts of Eimeria bovis are found. The schizonts of E. auburnensis resembled the previously described large microgametocytes of this species but were distinguishable morphologically and by histochemical stains. The microgametocytes were much larger than previously reported; one measured 91 by 287.5 μ.     

Clinical coccidiosis in raccoons (Procyon lotor)

Clinical coccidiosis was diagnosed in wild-caught and captive raccoons. Eimeria procyonis-like oocysts were seen in 15 of 15 captive raccoons. In 6 of 6 juvenile wild-caught raccoons examined at necropsy, endogenous coccidian stages were seen in the small intestine. Two types of schizonts (large and small) were identified. Large schizonts were up to 110 microm long, contained 10-microm-long merozoites, and were in crypt glandular epithelial cells. Smaller schizonts were 10 microm long, contained 5-microm-long merozoites, and were at the tips of the villi. Only a few gamonts and no oocysts were seen in sections. These stages were thought to be of E. procyonis.     

Isospora manchacensis n. sp., an intranuclear coccidian from the Louisiana ground skink, Scincella lateralis (Say, 1823) (Lacertilia: Scincidae)

Isospora manchacensis n. sp. is described from ground skinks, Scincella lateralis (Say, 1823) from Louisiana. Overall prevalence at 6 sites near Lake Ponchartrain was 43.1% (59/137) and ranged from 8% (1/13) to as high as 60% (6/10). Endogenous stages develop inside the nuclei of epithelial cells in the small intestine. Infected hypertrophic nuclei migrate from the basal lamina of the host cell to the luminal striated border. Oocysts in freshly passed fecal pellets usually contain a single contracted sporont that divides to form 2 sporoblasts. These undergo a brief pyramid stage followed by sporulation within 45-50 hr. Sporulated oocysts have a single-layered wall and measure 25.0 X 22.6 (20.0-28.9 X 18.6-26.0) micron. The lemon-shaped sporocysts measure 12.8 X 10.2 (11.1-15.2 X 9.0-11.0) micron and contain a Steida body, a spherical to oval substeida body, and a dispersed, granular sporocyst residuum. Prepatent periods in skinks fed 700 and 1,400 oocysts ranged from 24 to 32 days. Experimentally infected skinks produced large numbers of oocysts continuously during the 3-4 wk they were monitored after the onset of patency, but exhibited no signs of disease. Experimental doses of 200 oocysts failed to produce infections in skinks monitored for as long as 7 wk.     

Isospora lacazei (Labbe, 1893) and I. chloridis sp. n. (Protozoa: Eimeriidae) from the English Sparrow (Passer domesticus), Greenfinch (Chloris chloris) and Chaffinch (Fringilla coelebs)

SYNOPSIS. Two species of Isospora are described from Chloris chloris with the additional hosts Passer domesticus and Fringilla coelebs. I. lacazei Labbé has spherical oocysts measuring 16.6 to 30.0 μ; the oocyst wall is colorless and smooth, consisting of a thick layer and, in the majority of oocysts, an inner thin membrane. Stages of the life cycle in the epithelial cells of the duodenum are described. The internal stages consist of first and late generation schizonts which produce merozoites without any residual body, spindle-shaped microgametes and macrogametes without obvious "plastic granules." The oocysts of I. chloridis sp. n. have colorless, smooth surfaced walls of one thick layer. They are ellipsoidal, measuring 17.2-33.2 μ× 16.6-30.0 μ. The internal stages of this species infect the epithelial cells of the small intestine in the same region as I. lacazei. They produce 2 generations of schizonts, consisting of merozoites and a residuum; microgametes are comma-shaped and macrogametes have obvious "plastic granules."     

Coccidiosis of sandhill cranes (Grus canadensis) wintering in New Mexico

The feces of 212 sandhill cranes (Grus canadensis) collected in central New Mexico from October 1982 to January 1983 and from October 1983 to January 1984 were examined to determine the prevalence of coccidial oocysts. One hundred forty-five granulomatous nodules from the viscera of 64 cranes and samples of lung, small intestine, and large intestine from 58 birds were examined by light and transmission electron microscopy for the presence of intestinal or extraintestinal coccidiosis. Of the 212 fecal samples, 160 (75%) were positive for oocysts of Eimeria, including E. gruis in 139 (66%) and E. reichenowi in 118 (56%) of the samples. Eimeria bosquei sp. n. was found in two (approximately 1%) of the fecal samples. Subspheroid to ovoid oocysts of this new species are 19-27 X 14-19 (23.6 X 17.1) micrograms with ovoid sporocysts 10-14 X 7-11 (12.3 X 9.3) micrograms. A rough, heavily pitted outer oocyst wall, sporocyst residuum, Stieda and substieda bodies, and multiple polar bodies are present. The polar bodies, of varying sizes, always aggregate at the apex of the sporulated oocyst. An Adelina sp. was found in one (0.5%) crane. Coccidian developmental stages were found in the epithelium and lamina propria of the small and large intestine. Disseminated granulomatous nodules were found in the oral mucosa, esophagus, heart, descending aorta, liver, small intestine, mesenteries, and parietal peritoneum. Unique cell types resembling coccidian asexual and sexual stages were observed by light and electron microscopy in some of the nodules.     

Coccidia of wombats: correction of host-parasite relationships. Eimeria wombati (Gilruth and Bull, 1912) Comb. Nov. and Eimeria ursini Supperer, 1957 from the hairy-nosed wombat and Eimeria arundeli sp. n. from the common wombat.

Coccidial oocysts morphologically consistent with Eimeria ursini Supperer 1957, and E. tasmaniae Supperer 1957 were recovered from the feces of wild and captive hairy-nosed wombats (Lasiorhinus latifrons) in Australia. Eimeria arundeli so. n. was recovered from the feces of wild and captive common wombats (Vombatus ursinus). Eimeria arundeli oocysts are ellipsoidal to slightly ovoid 60.2--67.2 (63.7) X 40.6--47.6 (43.4); micropyle 3 in diameter usually visible; with oocyst wall granular, dark brown and occasionally opaque, 4--7 thick; inner oocyst wall clear, about 1.5 thick; small oocyst residuum present, four sporocysts ovoid 22.4--29.4 (25.8) X 12.6--15.4 (14.1) with protuberant Stieda body; opposite end of sporocyst also often slighly pointed; large granular sporocyst residuum obscuring sporozoites. Gametocytes of E. arundeli sp. n. and of an organism which is consistent with E. tasmaniae, are described developing in the lamina propria of villi in the small intestine. The stages in the hairy-nosed wombat are those described as Ileocystis wombati Gilruth and Bull 1912. It is suggested that the identification of the host of Supperer's E. ursini and E. tasmaniae as V. ursinus was in error and that the allopatric L. latifrons is the natural host. Eimeria tasmaniae Supperer 1957 is suppressed and E. wombati (Gilruth and Bull, 1912) comb. nov. is proposed and redescribed. No schizonts were identified among the endogenous stages, consistent with observations in the literature on other coccidia with similar gametocyte and oocyst structure.     

Eimeria and sarcocystis in raccoons in Illinois

Eimeria nuttalli oocysts were found in 58% (21/36) and E. procyonis oocysts in 25% (9/36) of raccoons Procyon lotor in Illinois, and sporocysts of Sarcocystis sp. in 17% (2/12) of other raccoons in Illinois. The oocysts of E. nuttalli were ellipsoidal to ovoid, 15-21 X 12-17 micrometer, with a one-layered, smooth, colorless wall. The oocysts of E. procyonis were 22-28 X 18-22 micrometer, with a rough, striated, brownish, two-layered wall. The sporulated sporocysts of Sarcocystis sp. were 11-13 X 8-10 micrometer. Attempts to infect baby pigs by feeding them sporocysts of Sarcocystis sp. from the reaction failed.     

The endogenous stages of Eimeria utahensis (Protozoa: Eimeriidae) in the kangaroo rat, Dipodomys ordii

The endogenous life cycle of Eimeria utahensis is described from experimentally infected kangaroo rats, Dipodomys ordii. The endogenous asexual cycle consisted of 4 generations of meronts. First-generation meronts were concentrated in the anterior third of the small intestine. The succeeding generations of meronts and the sexual stages were concentrated in the middle third of the small intestine. First-generation meronts had a mean diameter of 9.7 micrometer and contained 12 to 16 merozoites. Second-generation meronts had a mean diameter of 8.0 micrometer and contained 12 to 16 merozoites and a residual body. Third-generation meronts had a mean diameter of 12.4 micrometer and contained 4 to 8 merozoites. Fourth-generation meronts had a mean diameter of 8.6 micrometer and contained 16 to 24 merozoites. Young gamonts were located in epithelial cells of the crypts of the small intestine. Shortly after the parasites entered the epithelial cells, the infected cells became displaced into the lamina propria, and most of the mature gamonts were in this location. The nuclei of host cells containing young sexual stages became greatly elongated and flattened. A few young gamonts were seen in cells in which the host cell nuclei were dividing. During development, nuclei of microgamonts became arranged on the periphery of numerous compartments. Only one type of wall-forming body could be distinguished in the macrogamonts.     

家兔体内黄艾美耳球虫的发育史观察

为了解家兔(Oryctolagus curiculus)黄艾美耳球虫(Eimeria flavescens)的内生发育史,用不同接种剂量感染20只无球虫兔,采用常规石蜡切片技术进行研究。共观察到4代裂殖生殖和1代配子生殖。每一代裂殖生殖阶段都含有2种类型的裂殖体:粗型和细型。第1代裂殖生殖发生于感染后60～72h,主要位于空肠的腺上皮;第2代裂殖生殖发生于感染后84h,位于盲肠和结肠的腺上皮;第3代裂殖生殖发生于感染后96～120h,位于盲肠和结肠的绒毛上皮;第4代裂殖生殖发生于感染后144～153h,位于结肠和盲肠的腺上皮。感染后167h,开始配子生殖阶段,成熟卵囊出现于感染后215h。本研究中对于裂殖生殖代数划分与文献报道不同,并观察到2种形态的裂殖体。     

Life Cycle of Isospora canis Nemeséri, 1959 in the Dog*

The life cycle of I. canis Nemeséri, 1959 was studied in experimentally infected dogs. Freshly sporulated oocysts were ovoid and 34–40 × 28–32 μm. The endogenous stages were found directly beneath the epithelium of the distal portion of the small intestinal villi. Most of the endogenous stages were in the lower 1/3 of the small intestine, but occasionally they were found in other portions of the small intestine. Three asexual generations were present. First-generation schizonts were 16–38 × 11–23 μm and contained 4–24 merozoites; mature 1st-generation merozoites were 8–11 × 3–5 μm. First-generation schizogony lasted up to 7 days after inoculation. Second-generation schizonts were 12–18 × 8–13 μm and contained up to 12 merozoites which were 11–13 × 3–5 μm. Second-generation schizogony was present on postinoculation days 6 and 7. Third-generation schizonts were formed by nuclear division of 2nd-generation merozoites. Most 2nd-generation merozoites underwent nuclear division without leaving the parasitophorous vacuole of the 2nd-generation schizont. Mature 3rd-generation schizonts were 13–38 × 8–24 μm and contained 6–72 merozoites. Third-generation merozoites were 8–13 × 1–3 μm. Third-generation schizogony was present on days 6–8 after inoculation. Mature macrogametes were 22–29 × 14–23 μm. Mature microgametocytes were 20–38 × 14–26 μm. Gametes were present on postinoculation days 7–10. Oocysts were present in tissue sections on postinoculation days 8–10 and 12. The prepatent period was 9–11 days.     

Ultrastructural differentiation of Toxoplasma gondii schizonts (types B to E) and gamonts in the intestines of cats fed bradyzoites

The ultrastructural characterisitics of four types of Toxoplasma gondii schizonts (types B, C, D and E) and their merozoites, microgamonts and macrogamonts were compared in cats killed at days 1, 2, 4 and 6 after feeding tissues cysts from the brains of mice. Schizonts, merozoites and gamonts contained most of the ultrastructural features characteristic of the phylum Apicomplexa. All four types of schizonts developed within enterocytes or intraepithelial lymphocytes. Occasionally, type B and C schizonts developed within enterocytes that were displaced beneath the epithelium into the lamina propria. Type D and E schizonts and gamonts developed exclusively in the epithelium. Tachyzoites occurred exclusively within the lamina propria. Type B schizonts formed merozoites by endodyogeny, whereas types C to E developed by endopolygeny. The parasitophorous vacuoles surrounding type B and C schizonts consisted of a single membrane, whereas those surrounding types D and E schizonts were comprised of two to four electron-dense membranes. The parasitophorous vacuole of type B schizonts had an extensive tubulovesicular membrane network (TMN); the TMN was reduced or absent in type C schizonts and completely absent in types D and E schizonts and gamonts. Type B merozoites were ultrastructurally similar to tachyzoites, except that they were slightly larger. Type C merozoites exhibited a positive periodic acid-Schiff reaction by light microscopy and ultrastructurally contained amylopectin granules. Rhoptries were labyrinthine in type B merozoites but were electron-dense in types C-E. The development of microgamonts, macrogamont and oocysts is also described.     

Life Cycle of Eimeria christenseni Levine,Ivens & Fritz, 1962 from the Domestic Goat,Capra hircus L.1

The endogenous development of Eimeria christenseni was studied in 10 two- to four-week-old kids inoculated with 10⁶-10⁷ sporulated oocysts. They were killed at intervals from two to 26 days after inoculation, and their tissues were examined for endogenous stages of the coccidian by light microscopy. Such stages were found in the small intestine and mesenteric lymph nodes. In the sexual cycle, two generations of meronts were found. The first generation developed in endothelial cells of lacteals in the jejunun and ileum and mesenteric lymph nodes, and mature meronts were first seen 14 days after inoculation. The second generation developed in epithelial cells of the glands of Lieberkuehn in the jejunum and ileum and in mesenteric lymph nodes, and its mature meronts were first seen by 16 days. Sexual stages were present mostly in epithelial cells of the tips and sides of the villi and less frequently in crypt cells of the jejunum and ileum. Mature macrogametes and microgamonts and oocysts were also first seen by 16 days. The prepatent period was 17 (14-23) days; the patent ranged from 8 to more than 30 days. Sporulation time was 3-4 days at 30°C. E. christenseni was found to be pathogenic, kids inoculated with 1-5 × 10⁵ sporulated oocysts exhibited the following signs: severe diarrhea, anorexia, polydipsia, poor hair coat, and extreme weakness. They recovered about a month later, but their growth rates appeared to be lower than those of uninoculated animals kept under the same conditions. One kid died 20 days after inoculation with 10⁷ oocysts.     

Coccidiosis in wild grey kangaroos

Deaths occurred among wild grey kangaroos (Macropus giganteus) whose habitat was subject to flooding. A sample of the involved juvenile animals was hypoproteinaemic, and extensive haemorrhagic enteritis, associated with the presence of coccidial life cycle stages was found in the small intestine at necropsy. Masses of small schizonts infected cells of the lamina propria; large schizonts occupied clusters of hypertrophied cells; macrogametes and microgametocytes were observed in cells of the lamina propria. The species of coccidia involved could not be determined, although oocysts of Eimeria cunnamullensis and E. kogoni were found in faeces. Overcrowding, food shortage, damp conditions and possibly feed supplementation with hay on the ground were considered probable epizootiological factors contributing to an outbreak of coccidiosis among juvenile animals.     

Eimeria cicaki sp. n. and Isospora thavari sp. n. from the house lizard Gehyra mutilata Boulenger in Malaysia.

Oocysts and endogenous stages of new species of Eimeria and Isospora from the house lizard, Gehyra mutilata, are described. The ellipsoid to subspherical 2-layered oocysts of E. cicaki averaged 24.0 X 21.0 mum. Polar granules are present. Micropyle and oocyst residuum are absent. Ellipsoid sporocysts average 12.2 X 9.0 mum. A sporocyst residuum is present, but the Stieda body is absent. Endogenous stages are in epithelial cells of the small intestine. The subspherical single-layered oocysts of I. thavari average 23.8 X 22.8 mum. The polar granule is present; micropyle and oocyst residuum are absent. Ellipsoid sporocysts average 12.8 X 9.4 mum. Stieda body and sporocyst residuum are present. There are endogenous stages in epithelial cells of the small intestine.     

Fatal toxoplasmosis and enteroepithelial stages of Toxoplasma gondii in a Pallas cat (Felis manul)

Toxoplasma gondii was found in tissues of a six-year-old female Pallas cat (Felis manul) from the Milwaukee County Zoo. Toxoplasma gondii meronts (types D and E), gamonts, and oocysts were present in the epithelium of the small intestine. Numerous unsporulated oocysts were present in the intestinal lumen. The cat died of acute, overwhelming toxoplasmosis. Necrotic enteritis, multifocal necrotizing granulomatous hepatitis, and pneumonia were the prominent lesions.     

Eimeria colchici sp. nov. (Protozoa: Eimeriidae), the Cause of Cecal Coccidiosis in English Covert Pheasants

SYNOPSIS. Eimeria colchici sp. n. is described from English pheasants Phasianus colchicus. It has cocysts measuring 19–33.5 (27.4) by 13–21 (16.7) μ, having both micropyle and polar granule. The large 1st and 2nd generation schizonts occur in the glands of the small intestine, 3rd generation schizonts occur deep in the glands of the ceca, and gametocytes occur in the epithelial cells of the ceca. The prepatent period is 6 days. In young pheasants the parasite causes coccidiosis characterized by formation of white cores in the ceca. Mortality is high in experimental infections. Zoalene (0.0125%) in the feed almost completely suppressed the infection; Amprolium (0.0125%) also gave good control, but sulfaquinoxaline (0.0125%) was not so effective. Sulfaquinoxaline, Saquadil and Sulfamezathine in the drinking water controlled mortality, but treatment had to be applied early to avoid weight losses.     

Fatal Toxoplasmosis and Enteroepithelial Stages of Toxoplasma gondii in a Pallas Cat (Felis manul)1

Toxoplasma gondii was found in tissues of a six-year-old female Pallas cat (Felis manul) from the Milwaukee County Zoo. Toxoplasma gondii meronts (types D and E), gamonts, and oocysts were present in the epithelium of the small intestine. Numerous unsporulated oocysts were present in the intestinal lumen. The cat died of acute, overwhelming toxoplasmosis. Necrotic enteritis, multifocal necrotizing granulomatous hepatitis, and pneumonia were the prominent lesions.