A New Species of Eimeria from the Golden-Mantled Ground Squirrel, Spermophilus lateralis, in Northern Colorado

Oocysts of Eimeria morainensis n. sp. are described from the golden-mantled ground squirrel, Spermophilus lateralis. in Northern Colorado. The oocysts of E. morainensis are double-walled and subspherical, 20.3 × 19.8 (18.7–26.2 × 17.5–21.2) μm; and the sporocysts are ellipsoid, 12.1 × 6.9 (8.7–13.7 × 6.2–8.7) μm. Oocyst residuum and micropyle are absent, but a polar granule is present. Sporocyst residuum and Stieda body are present. Differences in oocyst characteristics provide the basis for recognition of this new species of Eimeria.     

Identification of a novel species of Eimeria Schneider, 1875 from the woylie,Bettongia penicillata Gray (Diprotodontia: Potoroidae) and the genetic characterisation of three Eimeria spp. from other potoroid marsupials

Faecal samples (n = 1,093) collected from the woylie Bettongia penicillata Gray, in south-western Australia were examined for the presence of coccidian parasites. Eimeria sp. oöcysts were detected in 15.2% of samples. Faecal samples obtained from the eastern bettong Bettongia gaimardi (Desmarest) (n = 4) and long-nosed potoroo Potorous tridactylus (Kerr) (n = 12) in Tasmania, were also screened for the presence of Eimeria spp. (prevalence 50% and 41.7%, respectively). Morphological and genetic comparison with other known species of Eimeria indicates that the material identified in woylies is novel. This study aimed to (i) morphologically describe and genetically characterise Eimeria woyliei n. sp. found in woylies; and (ii) genetically characterise Eimeria gaimardi Barker, O’Callaghan & Beveridge, 1988, Eimeria potoroi Barker, O’Callaghan & Beveridge, 1988, and Eimeria mundayi Barker, O’Callaghan & Beveridge, 1988, from other potoroid marsupials. Molecular phylogenetic analyses conducted at the 18S rDNA and mitochondrial cytochrome c oxidase subunit 1 (cox1) loci revealed that E. woyliei n. sp. was most closely related to Eimeria setonicis Barker, O’Callaghan & Beveridge, 1988, at the 18S rDNA locus, and Eimeria trichosuri O’Callaghan & O’Donoghue, 2001, at the cox1 locus. Eimeria woyliei n. sp. is the sixth species of Eimeria to be formally described from potoroid marsupials.

     

Coproparasitological examinations and molecular determination of Eimeria species in Madura cattle reared on Madura Island,Indonesia

Madura cattle, which are native to Indonesia and mainly kept on Madura Island, East Java, are expected to contribute to improving the regional meat self-sufficiency. Eimeria spp. are the most pathogenic protozoans among gastrointestinal parasites in livestock but no molecular surveys of Eimeria spp. in Madura cattle have been conducted to date. In this study, a total of 183 fecal samples were collected from Madura cattle and 60 (32.8%) were positive for parasites of protozoans and nematodes by the sugar floatation method. Among the samples with parasites, Eimeria spp. oocysts were detected in 50 samples (27.3%) with an average OPG value of 1686.1. Eimeria spp. were successfully identified to the species level in 26 samples with Eimeria bovis being the most prevalent, followed by E. zuernii and E. aubrunensis. A total of 21 samples showed mixed infection of more than two species of Eimeria. E. bovis and E. zuernii have been recognized as having high virulency and, thus, these parasites are potential sources of severe coccidiosis and the cause of infections in other cattle. Although additional studies are warranted, these results can be helpful for improving the management and productivity of Madura cattle.     

Molecular identification of Eimeria species in Spanish bats

This is the first study reporting the detection and molecular characterization of Eimeria in bats in Spain, specifically in 12 of 32 chiropteran species described in the Iberian Peninsula. A total of 76 faecal samples were collected from different bat roosting sites across Spanish territory. The DNA was extracted from the samples and sequenced by targeting the Eimeria SSU-rRNA gene. Two Eimeria species were detected in 29 of the 76 faecal samples (38%), and the bat-specific Eimeria rioarribaensis and rodent-specific Eimeria jerfinica were detected in 4 (5%) and 25 (33%) of the samples, respectively. This is the first report of E. rioarribaensis in the bats Rhinolophus euryale, Myotis myotis and Nyctalus lasiopterus, extending the host and geographical ranges for this bat coccidian parasite. The identification of the rodent-specific parasite species E. jerfinica in bats indicates the occurrence of this species in Spain, although its presence has not previously been reported in wild rodents in this country. Considering that most of the Eimeria spp. reported in bats were described only on the basis of morphometric data, molecular studies are required to determined which Eimeria species occur in bats, to complete the identification of these species and to clarify the phylogeny.     

Eimeria odocoilei n. sp. from the Mule Deer Odocoileus h. hemionus in Washington*

SYNOPSIS. Eimeria odocoilei n. sp. is described from feces of a mule deer Odocoileus h. hemionus in Washington. Its oocysts are 26 to 28 by 22 to 26 μ. It is the second species of Eimeria described from this host.     

Some Problems of Host and Parasite Interactions in the Coccidia*

SYNOPSIS. The current status of some concepts of host and parasite interactions in the coccidia are discussed and evaluated. It is suggested that winter coccidiosis of cattle caused by Eimeria zuernii results from activation of arrested endogenous stages in the tissues of the host. A second aspect of clinical coccidiosis is that infections are seldom monospecific, but little work has been done on infections in animals with multiple species of coccidia. Information in the literature indicates that there are interactions between species of Eimeria in concurrent infections, and it is hoped that investigators will undertake studies to define more clearly what interactions there may be. Finally, the finding that there is a genetic basis for successful transmission of Eimeria separata from rats to mice provides a tool for studying the basis of host-specificity in the coccidia.     

Coccidia in Camels (Camelus dromedarius) in Saudi Arabia1

Saudi Arabian camels {Camelus dromedarius) are infected with three species of Eimeria: E. dromedarii (28.4%), E. rajasthani < 22.2%), and E. cameli (19.2%); 41.6% of the animals examined were positive. The highest prevalence of infection was reported in the western region of the country. Mixed infection with two Eimeria species is most common; E. dromedarii was most frequently and generally the most predominant species. Eimeria dromedarii and E. rajasthani are described for the first time from Saudi Arabian camels.     

Species of Eimeria in Nonepithelial Sites1

In a few homoiothermic host species, Eimeria spp. in a schizogonic stage, a gamogonic stage, or as resting sporozoites infect nonepithelial tissues. However, epithelium serves as a critical site in the cycle of these and all other species known from warm-blooded hosts. Eimeria funduli, infecting at least four different killifishes, undergoes both schizogony and gamogony in non-epithelial hepatic and pancreatic cells and requires an invertebrate host to complete its cycle. Oocysts are not released from the living fish into the environment. The cycle for this species, or aspects of it, may exemplify those found in several piscine species infecting nonepithelial (and possibly epithelial) cells. Eimeriu funduli differs from most species of Eimeria infecting homoiotherms in other respects, some of which may also characterize traits for piscine and other poikilotherm eimerians in general. Endogenous development is affected by temperature and host-age, sporogony occurs in the host, and infections occur in several related fishes. The presence of an intermediate host in at least E. funduli and the presence of sporozoites in macrophages of several eimerians of homoiotherms, as well as other features, suggest a closer relationship between eimeriids and Lankesterella, Schellackia, and even the Haemosporina than previously assumed.     

Using genetic analysis to determine the distribution,prevalence and diversity of Eimeria species in pest rabbits (Oryctolagus cuniculus) in Australia

To genetically assess the Australian distribution and frequency of Eimeria species in wild rabbits, with a primary focus on Eimeria intestinalis and Eimeria flavescens as possible additional agents of rabbit biocontrol, the distal colon and faecal samples from wild rabbits sourced from 26 Australian locations with mean annual rainfalls of between 252 mm and 925 mm were analysed using amplicon sequencing of the ITS1 region. Contrary to previous microscopy studies which had only detected E. flavescens on mainland Australia at Wellstead in south-west Western Australia, we detected this species at all 23 effectively sampled sites. The more pathogenic E. intestinalis was only found at 52.2% of sites. Three unique Eimeria genotypes were detected that did not align to the 11 published sequences using a pairwise-match threshold of 90%, and may represent unsequenced known species or novel species. One genotype we termed E. Au19SH and was detected at 20 sites, E. Au19CO was detected at eight sites, and E. Au19CN was detected in one rabbit at Crows Nest (Qld). Site diversity ranged from only five Eimeria species at Boboyan (ACT) to 13 unique sequences at Cargo (NSW). Eimeria diversity in individual rabbits ranged from 11 unique sequences in a rabbit at Wellstead (WA) and a rabbit at Cargo (NSW), to one in 17 rabbits and zero in six rabbits. The three rabbit age classes averaged 4.3 Eimeria species per rabbit. No relationship was found between the number of Eimeria species detected and mean annual rainfall. As Eimeria species were found to be fairly ubiquitous at most sites they appear to be an unlikely additional candidate to assist the control of pest rabbits in Australia.     

The impact of grazing by macropods on coastal foredune vegetation in southeast Queensland

Abstract The extent of grazing by two macropodids, the agile wallaby (Macropus agilis) and the swamp wallaby (Wallabia bicolor) on coastal foredunes on South Stradbroke Island in southeast Queensland was investigated to determine potential impacts on the principal sand colonizing species, sand spinifex grass (Spinifex sericeus). Grazing on spinifex grass on the foredunes of South Stradbroke island can be attributed principally to agile wallabies. Foraging activity by wallabies was higher in areas of high spinifex abundance, however, grazing intensity and impact on spinifex was only important on foredunes with low spinifex abundance. Spinifex consumption by wallabies was also related to a number of factors, especially composition and structure of vegetation in adjacent habitats. Spinifex consumption increased when the abundance of ground cover components (grasses, sedges, forbs) in adjacent habitats was low and structural complexity was high. Grazing on foredunes by wallabies significantly affects the species composition of the foredune community by excluding the establishment of a number of perennial foredune plant species. This may have implications for community succession in coastal ecosystems.     

Eimeria callosciuri n. sp. (Protozoa: Eimeriidae) from Prevost's Squirrel Callosciurus prevostii Demarest, 1822 in Malaysia*

SYNOPSIS. Eimeria callosciuri n. sp. is described from Prevost's squirrel Callosciurus prevostii in Malaysia. Its oocysts are 24–31 by 20–2μ with a mean of 21.9 by 28.4μ. Schizogonic and gametogonic stages develop in the tips of the villi of the small intestine, above the nuclei of the host epithelial cells. It is the first species of Eimeria described from the rodent tribe Callosciurini.     

Four New Species of Eimeria and One of Tyzzeria from the Ceylon Jungle Fowl Gallus lafayettei*

One species of Tyzzeria and 4 new species of Eimeria are described from the Ceylon jungle fowl Gallus lafayettei. The sporulated oocysts of Tyzzeria galli sp. n. are 13.8 (12–15) μ m; of Eimeria lafayettei sp. n., 19.5 (19–21) X 14.2 (13.5–15) μ m; of Eimeria indentata sp. n., 30.3 (29.5–32) X 21.4 (20–22) μ m; of Eimeria symmetrica sp. n., 35 × 28.5 μ m, and of Eimeria dissanaikei sp. n., 21 (19–23) X 14 (12–16) μ m. E. indentata, E. symmetrica, and E. dissanaikei produced patent infections in domestic fowl but T. galli and E. lafayettei did not. This is the 1st record of the genus Tyzzeria from the order Galliformes.     

Eimeria trichosuri: Phylogenetic position of a marsupial coccidium, based on 18S rDNA sequences

Phylogenetic analysis of the genus Eimeria suggests that parasite and host have coevolved over broad evolutionary timescales. Here we extend this analysis by determining the 18S rDNA gene sequence of the marsupial coccidium, Eimeria trichosuri, and assessing its phylogenetic position relative to Eimeria from birds, reptiles and placental mammals. This analysis placed E. trichosuri clones in a clade that diverged before the major clade comprising species from placental mammals. The position of E.trichosuri is consistent with host phylogeny where marsupials represent an ancient evolutionary line that predates the placental mammal line.     

Genetic and biological characterisation of three cryptic Eimeria operational taxonomic units that infect chickens (Gallus gallus domesticus)

More than 68 billion chickens were produced globally in 2018, emphasising their major contribution to the production of protein for human consumption and the importance of their pathogens. Protozoan Eimeria spp. are the most economically significant parasites of chickens, incurring global costs of more than UK £10.4 billion per annum. Seven Eimeria spp. have long been recognised to infect chickens, with three additional cryptic operational taxonomic units (OTUs) first described more than 10 years ago. As the world’s farmers attempt to reduce reliance on routine use of antimicrobials in livestock production, replacing drugs that target a wide range of microbes with precise species- and sometimes strain-specific vaccines, the breakthrough of cryptic genetic types can pose serious problems. Consideration of biological characteristics including oocyst morphology, pathology caused during infection and pre-patent periods, combined with gene-coding sequences predicted from draft genome sequence assemblies, suggest that all three of these cryptic Eimeria OTUs possess sufficient genetic and biological diversity to be considered as new and distinct species. The ability of these OTUs to compromise chicken bodyweight gain and escape immunity induced by current commercially available anticoccidial vaccines indicates that they could pose a notable threat to chicken health, welfare, and productivity. We suggest the names Eimeria lata n. sp., Eimeria nagambie n. sp. and Eimeria zaria n. sp. for OTUs x, y and z, respectively, reflecting their appearance (x) or the origins of the first isolates of these novel species (y, z).     

Eimeria balphae n. sp. from the Ord Kangaroo Rat Dipodomys ordii*

SYNOPSIS. Eimeria balphae n. sp. is described from the Ord kangaroo rat Dipodomys ordii. The sporulated oocysts are broadly ellipsoidal to ovoid, averaging 16.7 by 14.3 μ. A single, large, homogenous body represents the oocyst residuum. A polar granule is present. There is no micropyle. The ovoid sporocysts average 8.7 by 5.9 μ. The sporocyst residuum is composed of 7–14 round, clear granules. This species of Eimeria was found in 1 of 82 D. ordii in northwestern Utah.     

The Oocysts of Eimeria vermiformis sp. n. and E. papillata sp. n. (Protozoa: Eimeriidae) from the Mouse Mus musclus

SYNOPSIS. Eimeria vermiformis sp. n. and E. papillata sp. n. are described from the mouse Mus musculus. The sporulated oocysts of E. vermiformis are 18–26 by 15–21 μ (mean 23.1 by 18.4 μ); its sporocysts are 11–14 by 6–10 μ (mean 12.8 by 7.9 p). The sporulated oocysts of E. papillata are 18–26 by 16–24 μ (mean 22.4 by 19.2 μ); its sporocysts are 10–13 by 6–9 μ (mean 11.2 by 8.0 μ). A substiedal body is present in E. papillata sporocysts. Patent infections were produced in white laboratory mice with both species. Fourteen species of Eimeria have now been described from the genus Mus.