FIGURES 20-26 - uploaded by Donald W Duszynski
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Eimeria calentinei. 20. Sporulated oocyst showing micropyle and oocyst residuum. 21. Outer layer of oocyst wall being broken off. 22. Sporocyst before addition of excysting fluid showing Stieda body. 23, 24. Sporocysts after addition of excysting fluid; note disappearance of Stieda body and increasing transparency of sporocyst wall. 25, 26. Sporozoite slowly excysting after repeated reentry into sporocyst. Fifty sporulated oocysts without their outer measured 27 to 35 by 19 to 22 (30.7 b y 20.7), layer measured 27 to 33 by 1 9 to 22 (28.9 by with shape indices 1.33 to 1.68 (1.48). 20.7), with shape indices 1.29 to 1.63. (1.44).
Source publication
Oocysts of Eimeria banffensis Lepp, Todd, and Samuel, 1972, Eimeria cryptobarretti sp. n., Eimeria princepsis sp. n., and Eimeria calentinei sp. n. are described from the Colorado pika, Ochotona princeps, collected from 3 mountain sites in Colorado. Subspherical oocysts of E. banffensis measure 23 to 34 by 18 to 25 μ (mean 27.6 by 23.0 μ) with ovoi...
Similar publications
An examination of the feces from 8 pikas collected in 1999 and from 17 pikas collected in 2009 in Mongolia revealed the presence of 3 new eimerian species. Four of the 5 species of pikas present in Mongolia were studied including: Ochotona alpina, O. dauurica, O. pallasi, and O. hyperborea. Oocysts of Eimeria dunnumi n. sp. from O. hyperborea colle...
Citations
... After exit of the sporozoites, the proteolytic trypsin can simultaneously enter the sporocyst and degrades the sporocyst wall, indicated by the disappearing mCherry signal. For some avian Eimeria species, the degradation of sporocyst walls under influence of trypsin had also been described [27] and supports our observations and interpretation. Analogous observations were made for the oocyst wall of E. nieschulzi. ...
Background:
The family of cysteine rich proteins of the oocyst wall (COWPs) originally described in Cryptosporidium can also be found in Toxoplasma gondii (TgOWPs) localised to the oocyst wall as well. Genome sequence analysis of Eimeria suggests that these proteins may also exist in this genus and led us to the assumption that these proteins may also play a role in oocyst wall formation.
Methods:
In this study, COWP-like encoding sequences had been identified in Eimeria nieschulzi. The predicted gene sequences were subsequently utilized in reporter gene assays to observe time of expression and localisation of the reporter protein in vivo.
Results:
Both investigated proteins, EnOWP2 and EnOWP6, were expressed during sporulation. The EnOWP2-promoter driven mCherry was found in the cytoplasm and the EnOWP2, respectively EnOWP6, fused to mCherry was initially observed in the extracytoplasmatic space between sporoblast and oocyst wall. This, so far unnamed compartment was designated as circumplasm. Later, the mCherry reporter co-localised with the sporocyst wall of the sporulated oocysts. This observation had been confirmed by confocal microscopy, excystation experiments and IFA. Transcript analysis revealed the intron-exon structure of these genes and confirmed the expression of EnOWP2 and EnOWP6 during sporogony.
Conclusions:
Our results allow us to assume a role, of both investigated EnOWP proteins, in the sporocyst wall formation of E. nieschulzi. Data mining and sequence comparisons to T. gondii and other Eimeria species allow us to hypothesise a conserved process within the coccidia. A role in oocyst wall formation had not been observed in E. nieschulzi.
... This species was first described from O. princeps in Colorado, United States, by Duszynski and Brunson (1973) and Duszynski (1974). Later it was found in O. collaris from Alaska, United States, and in O. hyperborea from Siberia, Russia (Lynch et al., 2007). ...
Fifty-two fecal samples from the Plateau pika, Ochotona curzoniae, collected in the Haibei Area, Qinghai Province, China, were examined for the presence of coccidia (Apicomplexa: Eimeriidae). Five distinct morphotypes, all Eimeria species, were distinguished based on the structure of their sporulated oocysts. Three of these included Eimeria banffensis, Eimeria calentinei, and Eimeria cryptobarretti, all of which have been described previously from other Ochotona species. We also studied 2 morphotypes that we feel have sufficient qualitative and quantitative characters to distinguish them from all previously described species; herein, we identify them as putative new species. Eimeria qinghaiensis n.sp. was found in 18/52 (35%) O. curzoniae. It has ovoidal oocysts with a 3-layered wall, with a rough outermost layer and a micropyle, approximately 9 microm wide. Sporulated oocysts are 37.2 x 27.2 (34-41 x 24-32) microm; 1 polar granule is present, but an oocyst residuum is absent. Sporocysts are ovoidal, 16.6 x 9.8 (14-19 x 9-11) microm with a Stieda body; sporocyst residuum and sporozoites have 2 refractile bodies. Eimeria haibeiensis n. sp. was found in 21/52 (40%) pikas. It has ellipsoidal to ovoidal oocysts, with a 2-layered smooth wall and a micropyle, 3.9 microm wide. Oocysts are 22.2 x 16.2 (20-24 x 15-18) microm; polar granule and oocyst residuum are both absent. Sporocysts are ovoidal, 11.6 x 6.6 (10-13 x 5-7) microm, with a Stieda body; sporocyst residuum and sporozoites each have 2 refractile bodies, 1 at each end. The 5 eimerian species we discovered in O. curzoniae in China all represent new host and locality records.
An examination of the feces from 8 pikas collected in 1999 and from 17 pikas collected in 2009 in Mongolia revealed the presence of 3 new eimerian species. Four of the 5 species of pikas present in Mongolia were studied including: Ochotona alpina, O. dauurica, O. pallasi, and O. hyperborea. Oocysts of Eimeria dunnumi n. sp. from O. hyperborea collected in 1999 are ellipsoid, average length and width of 31.4 x 20.8 μm, with a 1.4 μm thick double layered wall, lacking a micropyle, oocyst residuum, and polar granule. Sporocysts of this species are ellipsoid, 12.8 x 8.1 μm in length and width, with a steida body and a compact sporocyst residuum. Oocysts of Eimeria burti n. sp., from O. pallasi collected in 2009 are ovoid, 26.3 x 21.1 μm in average length and width, with a 1.6 μm thick double layered wall with an oocyst residuum. Their sporocysts are ellipsoidal, with a length and width of 11.4 x 7.8 μm with a prominent steida body. Oocysts of Eimeria salazarbravoi n. sp., from O. pallasi collected in 2009 are ovoidal, 26.6 x 20.5 μm in average length and width, with a 1.6 μm thick double layered wall, with a micropyle. Their sporocysts are ellipsoidal, with a length and width of 11.6 x 7.6 μm with a prominent Steida body and a compact sporocyst residuum. Species of Ochotona, pikas, are found in habitats ranging from semi-desert to taiga and high mountains across the Holarctic. The majority of the 30 currently recognized species occur in Asia, with only 2 species occurring in North America (HOFFMANN & SMITH 2005). Five of the Asian representatives of this genus occur in Mongolia. Ochotona hyperborea (PALLAS, 1811), the northern pika, has a broad distribution across Asia, from the Ural Mountains to the Pacific and south into northern Mongolia and China. In Mongolia they are common in the talus slopes and mountain steppe habitats of the northern part of the country. PALLAS’ pika, Ochotona pallasi (GRAY, 1867), has a disjunct distribution, with populations of this species ranging from Kazakhstan east through the Altai Mountains, across Mongolia into the Tuva region of Russia, and Xinjiang and Inner Mongolia of China. This species is found in the southern region of Mongolia in the southern Khangay Mountains and along the stretch of the Gobi Altai and Mongolian Altai Mountains. The alpine pika, Ochotona alpina (PALLAS, 1773), is found from northwestern Afghanistan across southern Russia, northern Mongolia, and China. In Mongolia this species ranges across the Mongolian Altai and the Khentey and Khangay Mountains. Ochotona dauurica (PALLAS, 1776), the Daurian pika, has a range extending east from the Altai Mountains of Russia across Tuva and Transbaikalia, and south into Mongolia and China. They occupy suitable habitat through the Mongolian and Gobi Altai Mountains as well as steppe habitats in the northern part of Mongolia. HOFFMANN’s pika, Ochotona hoffmanni (FORMOZOV et al., 1996), has the smallest geographic distribution, occurring only in the northern Khentey Mountains and bordering areas of the Transbaikal region of Russia (TINNIN et al. 2002, HOFFMANN & SMITH 2005, BATSAIKHAN et al. 2010, TINNIN et al. 2011a). Recent papers have addressed the apicomplexan parasites of pikas from Beringia and northern China (LYNCH et al. 2007, CAO et al. 2009). To date there have been 18 species of Eimeria described from 7 species of Ochotona from scattered localities ranging across the Holarctic from Turkmenistan to Colorado (LYNCH et al. 2007, CAO et al. 2009). There have been, however, no reports of Eimeria from Mongolian pika, although we have contributed previous data from other Mongolian host species (GARDNER et al. 2009, TINNIN et al. 2011b). Herein we continue our efforts to report on Mongolian Apicomplexa represented by the description of 3 new species of Eimeria.
Eimeria, one of several genera of protozoans in the phylum Apicomplexa referred to as coccidian, is highly host specific. Infection with coccidia seriously impairs the growth and survival of hosts. Coccidia, thus, potentially are excellent agents for biological control of rodents. We studied effect of coccidia on mortality of plateau pikas (Ochotona curzoniae). Pikas were given 6 000 × 10 4/mL., 600 × 10 4/mL 60 × 10 4/mL, 6 × 10 4/mL and 0. 6 × 10 4/mL oocysts each of Eimeria cryptobarretti and E. klondikensis for adults, or 600 × 10 4/mL, 60 × 10 4/mL, 6 × 10 4/mL of each for sub-adults, by stomach intubation. The prepatent period of adult death was 8 days. The mortality rate among infected pikas was dependent on the initial quantity of oocysts administered. Infection with 600 × 10 4/mLoocysts caused most adults to die. In addition, a majority of sub-adults also died after 4 days when they were infected with 60 × 10 4/mL oocysts. Not significant difference in mortality was found between males and females. The group infected with 60 × 10 4/mL oocysts produced more oocysts than other groups. Our results suggest that it is possible that coccidia, as agents of biological rodent control, could reduce the damages of pika to grassland.
The Biology and Identification of the Coccidia (Apicomplexa) of Turtles of the World is an invaluable resource for researchers in protozoology, coccidia, and parasitology, veterinary sciences, animal sciences, zoology, and biology. This first-of-its-kind work offers a taxonomic guide to apicomplexan parasites of turtles that enables easy parasite identification, with a summary of virtually everything known about the biology of each known parasite species. It is an important documentation of this specific area, useful to a broad base of readers, including researchers in biology, parasitology, animal husbandry, diseases of wild and domestic animals, veterinary medicine, and faculty members in universities with graduate programs in these areas. There are about 330 turtle species on Earth; many are endangered, a growing number of species are kept as pets, and some are still used as food by humans. Turtles, like other vertebrate animals have many different kinds of parasites (viruses, bacteria, protozoa, worms, arthropods, and others). Coccidiosis in turtles has prevented large-scale turtle breeding, and represents a serious problem in need of control. This succinct and highly focused book will aid in that effort. Offers line drawings and photomicrographs of each parasite from each hosts species Provides methods of identification and treatment Presents a complete historical rendition of all known publications on coccidia (and their closest relatives) from all turtle species on Earth, and evaluates the scientific and scholarly merit of each Provides a complete species analysis of the known biology of every coccidian described from turtles Reviews the most current taxonomy of turtles and their phylogenetic relationships needed to help assess host-specificity and evaluate what little cross-transmission work is available.
In vitro excystation of sporozoites of the heteroxenous coccidian Caryospora simplex Léger, 1904 (Apicomplexa: Eimeriorina) is described. Sporocysts freed mechanically from oocysts released a maximum of 51% of their sporozoites within 45 min at 25°C and a maximum of 74% within 20 min at 37°C when incubated in a 0.25% (w/v) trypsin–0.75% (w/v) sodium taurocholate (bile salt) excystation solution. At emergence from sporocysts, sporozoites were weakly motile then became highly active after about 2 min in excystation solution. Sporozoites within sporocysts exposed to bile salt only became highly motile within 25 min at 25°C and within 15 min at 37°C but did not excyst. When exposed only to trypsin at the above temperatures, the Stieda body dissolved; the substieda body remained intact, and the sporozoites exhibited only limited motility within sporocysts; only a few excysted. Intact, sporulated oocysts incubated at 25° or 37°C in 0.02 M cysteine-HC1 and a 50% CO2 atmosphere for 18 h had no morphologic changes in the oocyst wall. Further incubation of these intact oocysts in excystation solution for 30 min at 37°C caused neither motility of sporozoites within sporocysts nor excystation. Grinding oocysts for 30 sec in a motor-driven, teflon-coated tissue grinder caused motility of some sporozoites within sporocysts but did not result in excystation.
SYNOPSIS. Oocysts of Isospora serini and Isospora canaria, from the canary Serinus canarius, were broken, added to a cell suspension, fixed in Karnovsky's fluid, and studied in the electron microscope. The oocyst wall of each species had an electronlucent inner layer, a more osmiophilic middle layer and an outer layer of electron-lucent (I. serini) or electron-dense material interspersed with some electron-lucent material (I. canaria). A few, relatively large lipid-like bodies were present in the outer or middle layer of the oocyst wall of I. canaria. As many as 9 membranes were present in the oocyst wall of I. canaria and 3 in that of I. serini. When exposed to a trypsin-sodium taurocholate fluid, sporozoites of I. serini excysted from 5-month-old sporocysts in vitro, but not from sporocysts stored for more than 6 months. No excystation occurred in 15-month-old I. canaria sporocysts. Similarities and differences in excystation between I. serini and other Isospora, Eimeria, and Sarcocystis species are discussed.
The in vitro excystation process of sporozoites of Isospora arctopitheci Rodhain, 1933 from the titi marmoset Saguinus geoffroyi and of Isospora bigemina (Stiles, 1891) Lhe, 1906 from the bobcat, Lynx rufus is presented. Sporocysts of both species lack a Stieda body and when exposed to a trypsin-sodium taurocholate (pH 7.4) excysting fluid the walls of both collapse in a similar fashion, along apparently predetermined lines. Similarities and differences in excystation between I. arctopitheci, I. bigemina, and other Isospora, Eimeria, and Sarcocystis species are summarized. Such studies show that 2 distinct patterns of sporozoite excystation have been described to date, and both appear to be related to the structure of the sporocyst.
The ultrastructural changes which occur during the in vitro excystation of the sporozoites of Toxoplasma gondii were examined. The excystation was carried out at 37 degrees C on suspensions of oocysts which had been ground and then treated with an excysting medium containing 0.25% trypsin and 0.75% sodium taurocholate in phosphate buffered saline, pH 7.3. It was found that sporocysts within intact oocysts were unaffected while sporocysts exposed to the medium ruptured. The sporocyst wall consisted of two layers and during excystation the four plates which form the inner layer started to curl inward. At the same time changes were seen at the specialized junctions between these plates. When the junctions finally break, the plates separate. The outer layer of the sporocyst wall is then ruptured at points directly above where the plates were joined. Each of the four portions of the sporocyst wall curled inward to form a tightly wound whorl. The sporozoites can escape through the openings created between the portions of the sporocyst wall.
The in vitro excystation process of sporozoites of Isospora arctophitheci Rodhain, 1933 from the titi marmoset Saguinus geoffroyi and of Isospora bigemina (Stiles, 1891) Lühe, 1906 from the bobcat, Lynx rufus is presented. Sporocysts of both species lack a Stieda body and when exposed to a trypsin-sodium taurocholate (pH 7.4) excysting fluid the walls of both collapse in a similar fashion, along apparently predetermined lines. Similarities and differences on excystation between. I. arctopitheci, I. bigemina, and other Isospora, Eimeria, and Sarcocytis species are summarized. Such studies show that 2 distinct patterns of sporozoite excystation have been described to date, and both appear to be related to the structure of the sporocyst.
