''Eimeria'' is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

apicomplexa The Apicomplexa (also called Apicomplexia; single: apicomplexan) are organisms of a large phylum of mainly parasitic alveolates. Most possess a unique form of organelle structure that comprises a type of non-photosynthetic plastid called an ap ...

n parasites that includes various species capable of causing the disease

coccidiosis Coccidiosis is a parasitic disease of the intestinal tract of animals caused by coccidian protozoa. The disease spreads from one animal to another by contact with infected feces or ingestion of infected tissue. Diarrhea, which may become bloody ...

in animals such as

cattle Cattle (''Bos taurus'') are large, domesticated, bovid ungulates widely kept as livestock. They are prominent modern members of the subfamily Bovinae and the most widespread species of the genus '' Bos''. Mature female cattle are calle ...

poultry Poultry () are domesticated birds kept by humans for the purpose of harvesting animal products such as meat, Eggs as food, eggs or feathers. The practice of animal husbandry, raising poultry is known as poultry farming. These birds are most typ ...

and smaller

ruminant Ruminants are herbivorous grazing or browsing artiodactyls belonging to the suborder Ruminantia that are able to acquire nutrients from plant-based food by fermenting it in a specialized stomach prior to digestion, principally through microb ...

s including

sheep Sheep (: sheep) or domestic sheep (''Ovis aries'') are a domesticated, ruminant mammal typically kept as livestock. Although the term ''sheep'' can apply to other species in the genus '' Ovis'', in everyday usage it almost always refers to d ...

and

goat The goat or domestic goat (''Capra hircus'') is a species of Caprinae, goat-antelope that is mostly kept as livestock. It was domesticated from the wild goat (''C. aegagrus'') of Southwest Asia and Eastern Europe. The goat is a member of the ...

s. ''Eimeria'' species are considered to be monoxenous because the life cycle is completed within a single host, and stenoxenous because they tend to be host specific, although a number of exceptions have been identified. Species of this genus infect a wide variety of hosts. Thirty-one species are known to occur in

bat Bats are flying mammals of the order Chiroptera (). With their forelimbs adapted as wings, they are the only mammals capable of true and sustained flight. Bats are more agile in flight than most birds, flying with their very long spread-out ...

s (Chiroptera), two in turtles, and 130 named species infect fish. Two species (''E. phocae'' and ''E. weddelli'') infect seals. Five species infect llamas and alpacas: ''E. alpacae'', ''E. ivitaensis'', ''E. lamae'', ''E. macusaniensis'', and ''E. punonensis''. A number of species infect rodents, including ''E. couesii'', ''E. kinsellai'', ''E. palustris'', ''E. ojastii'' and ''E. oryzomysi''. Others infect poultry (''E. necatrix'' and ''E. tenella''), rabbits (''E. stiedai'') and cattle (''E. bovis'', ''E. ellipsoidalis'', and ''E. zuernii''). For full species list, see below. The most prevalent species of ''Eimeria'' that cause coccidiosis in cattle are ''E. bovis'', ''E. zuernii'', and ''E. auburnensis''. In a young, susceptible calf it is estimated that as few as 50,000 infective

oocysts Apicomplexans, a group of intracellular parasites, have life cycle stages that allow them to survive the wide variety of environments they are exposed to during their complex life cycle. Each stage in the life cycle of an apicomplexan organism ...

can cause severe disease. ''Eimeria'' infections are particularly damaging to the poultry industry and costs the United States more than $1.5 billion in annual losses. The most economically important species among poultry are ''E. tenella'', ''E. acervulina'', and ''E. maxima''. The oocysts of what was later called ''Eimeria stiedai'' were first seen by the pioneering Dutch microscopist

Antonie van Leeuwenhoek Antonie Philips van Leeuwenhoek ( ; ; 24 October 1632 – 26 August 1723) was a Dutch microbiologist and microscopist in the Golden Age of Dutch art, science and technology. A largely self-taught man in science, he is commonly known as " ...

(1632–1723) in the

bile Bile (from Latin ''bilis''), also known as gall, is a yellow-green/misty green fluid produced by the liver of most vertebrates that aids the digestion of lipids in the small intestine. In humans, bile is primarily composed of water, is pro ...

of a

rabbit Rabbits are small mammals in the family Leporidae (which also includes the hares), which is in the order Lagomorpha (which also includes pikas). They are familiar throughout the world as a small herbivore, a prey animal, a domesticated ...

in 1674. The genus is named after the German

zoologist Zoology ( , ) is the scientific study of animals. Its studies include the structure, embryology, classification, habits, and distribution of all animals, both living and extinct, and how they interact with their ecosystems. Zoology is one ...

Theodor Eimer Gustav Heinrich Theodor Eimer (22 February 1843 – 29 May 1898) was a German zoologist. He was a popularizer of orthogenesis, a form of directed evolution through mutations that made use of Lamarckian principles. Life and work Eimer was born ...

(1843–1898).

Life cycle

The ''Eimeria'' life cycle has an

exogenous In a variety of contexts, exogeny or exogeneity () is the fact of an action or object originating externally. It is the opposite of endogeneity or endogeny, the fact of being influenced from within a system. Economics In an economic model, an ...

phase, during which the oocysts are excreted into the environment, and an

endogenous Endogeny, in biology, refers to the property of originating or developing from within an organism, tissue, or cell. For example, ''endogenous substances'', and ''endogenous processes'' are those that originate within a living system (e.g. an ...

phase, where parasite development occurs in the host intestine. During the endogenous phase, several rounds of

schizogony Fission, in biology, is the division of a single entity into two or more parts and the regeneration of those parts to separate entities resembling the original. The object experiencing fission is usually a cell, but the term may also refer to ho ...

(asexual reproduction) take place, after which the

sexual differentiation Sexual differentiation is the process of development of the sex differences between males and females from an undifferentiated zygote. Sex differentiation is usually distinct from sex determination; sex determination is the designation of the de ...

gamete A gamete ( ) is a Ploidy#Haploid and monoploid, haploid cell that fuses with another haploid cell during fertilization in organisms that Sexual reproduction, reproduce sexually. Gametes are an organism's reproductive cells, also referred to as s ...

s and

fertilisation Fertilisation or fertilization (see spelling differences), also known as generative fertilisation, syngamy and impregnation, is the fusion of gametes to give rise to a zygote and initiate its development into a new individual organism or of ...

occurs. Parasite transmission occurs via the fecal-oral route. Infections are common in farming environments where many animals are confined in a small space. 450px, ''Eimeria'' life cycle

Oocysts

There are two forms of

oocyst Apicomplexans, a group of intracellular parasites, have life cycle stages that allow them to survive the wide variety of environments they are exposed to during their complex life cycle. Each stage in the life cycle of an apicomplexan organism ...

: sporulated or late oocyst, and unsporulated or early oocyst. An infected host releases oocysts into the environment in their unsporulated form. These contain a multi-layered cell wall making them highly resistant to environmental pressures. Once released, the unsporulated oocysts undergo

meiosis Meiosis () is a special type of cell division of germ cells in sexually-reproducing organisms that produces the gametes, the sperm or egg cells. It involves two rounds of division that ultimately result in four cells, each with only one c ...

upon contact with oxygen and moisture. This process is known as

sporulation In biology, a spore is a unit of sexual (in fungi) or asexual reproduction that may be adapted for dispersal and for survival, often for extended periods of time, in unfavourable conditions. Spores form part of the life cycles of many plant ...

and the oocysts take approximately 2 to 7 days to become infectious. The sporulated oocyst is said to be tetrasporic meaning it contains four sporocysts, while each sporocyst is dizoic, i.e. it contains two sporozoites. Once ingested, the oocysts undergo a process called excystation, whereby thousands of sporozoites are released into lumen of the intestine. In the case of ''E. tenella'', this process is thought to occur due to the combination of enzymatic degradation and mechanical abrasion of the oocyst wall in the chicken's

gizzard The gizzard, also referred to as the ventriculus, gastric mill, and gigerium, is an organ found in the digestive tract of some animals, including archosaurs (birds and other dinosaurs, crocodiles, alligators, pterosaurs), earthworms, some gast ...

Sporozoites

The motile

sporozoites Apicomplexans, a group of intracellular parasites, have life cycle stages that allow them to survive the wide variety of environments they are exposed to during their complex life cycle. Each stage in the life cycle of an apicomplexan organism ...

invade the

enterocyte Enterocytes, or intestinal absorptive cells, are simple columnar epithelial cells which line the inner surface of the small and large intestines. A glycocalyx surface coat contains digestive enzymes. Microvilli on the apical surface increase ...

s of small intestine, and migrate to their respective sites of development. Invasion is mediated through specialised membrane-bound structures on the surface of the parasite that release secretions. This results in the recognition of, and attachment to

host cell In biology and medicine, a host is a larger organism that harbours a smaller organism; whether a parasitic, a mutualistic, or a commensalist ''guest'' (symbiont). The guest is typically provided with nourishment and shelter. Examples include ...

receptor Receptor may refer to: * Sensory receptor, in physiology, any neurite structure that, on receiving environmental stimuli, produces an informative nerve impulse *Receptor (biochemistry), in biochemistry, a protein molecule that receives and respond ...

s. This process is known as

gliding motility Gliding motility is a type of translocation used by microorganisms that is independent of propulsive structures such as flagella, pili, and fimbriae. Gliding allows microorganisms to travel along the surface of low aqueous films. The mechanisms ...

, which is conserved across all species of ''

Apicomplexa The Apicomplexa (also called Apicomplexia; single: apicomplexan) are organisms of a large phylum of mainly parasitic alveolates. Most possess a unique form of organelle structure that comprises a type of non-photosynthetic plastid called an ap ...

''. Membrane glyconjugates have been proposed as potential host cell receptors for ''Eimeria'' species. After invasion, the sporozoites develop into

trophozoite A trophozoite (G. ''trope'', nourishment + ''zoon'', animal) is the activated, feeding stage in the life cycle of certain protozoa such as malaria-causing ''Plasmodium falciparum'' and those of the ''Giardia'' group. The complementary form of the t ...

s, then into

schizont Apicomplexans, a group of intracellular parasites, have life cycle stages that allow them to survive the wide variety of environments they are exposed to during their complex life cycle. Each stage in the life cycle of an apicomplexan organism ...

s, where they undergo several rounds of

asexual reproduction Asexual reproduction is a type of reproduction that does not involve the fusion of gametes or change in the number of chromosomes. The offspring that arise by asexual reproduction from either unicellular or multicellular organisms inherit the f ...

. This results in many nuclei developing within the schizont. Each nucleus develops into a

merozoite Apicomplexans, a group of intracellular parasites, have life cycle stages that allow them to survive the wide variety of environments they are exposed to during their complex life cycle. Each stage in the life cycle of an apicomplexan organism i ...

. Invasion requires the formation of a moving junction between parasite and host

cell membrane The cell membrane (also known as the plasma membrane or cytoplasmic membrane, and historically referred to as the plasmalemma) is a biological membrane that separates and protects the interior of a cell from the outside environment (the extr ...

s. In ''E. tenella'', this involves parasite

microneme Micronemes are secretory organelles, possessed by parasitic apicomplexans. Micronemes are located on the apical third of the protozoan body. They are surrounded by a typical unit membrane. On electron microscopy they have an electron-dense ma ...

s and

rhoptry A rhoptry is a specialized secretory organelle. They are club-shaped organelles connected by thin necks to the extreme apical pole of the parasite. These organelles, like micronemes, are characteristic of the motile stages of Apicomplexa protozoa ...

proteins including RON2, RON5 and AMA-2. It is unlikely that the host cell is completely passive in the invasion process, although evidence of host physical forces that assist in mediating parasite entry remains controversial.

Merozoites

When schizonts rupture, merozoites are released, which either go on to re-infect more

enterocytes Enterocytes, or intestinal absorptive cells, are simple columnar epithelial cells which line the inner surface of the small and large intestines. A glycocalyx surface coat contains digestive enzymes. Microvilli on the apical surface increase i ...

or develop into either male or female

gametes A gamete ( ) is a haploid cell that fuses with another haploid cell during fertilization in organisms that reproduce sexually. Gametes are an organism's reproductive cells, also referred to as sex cells. The name gamete was introduced by the Ge ...

via the process of

gametogenesis Gametogenesis is a biological process by which diploid or haploid precursor cells undergo cell division and differentiation to form mature haploid gametes. Depending on the biological life cycle of the organism, gametogenesis occurs by meiotic d ...

. These gametes fuse to form an oocyst, which is then released in its non-infectious, unsporulated form through the faeces of the host. Merozoite invasion also requires the formation of a moving junction, however the

protein Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residue (biochemistry), residues. Proteins perform a vast array of functions within organisms, including Enzyme catalysis, catalysing metab ...

s involved in this process differs from those on sporozoites.

Rhoptry A rhoptry is a specialized secretory organelle. They are club-shaped organelles connected by thin necks to the extreme apical pole of the parasite. These organelles, like micronemes, are characteristic of the motile stages of Apicomplexa protozoa ...

proteins AMA-1 and RON4 are found exclusively on merozoites. There is also a greater diversity of variant surface antigens found on the surface of merozoites. It is hypothesised that this may be due to the fact that merozoites are short-lived and a greater

antigen In immunology, an antigen (Ag) is a molecule, moiety, foreign particulate matter, or an allergen, such as pollen, that can bind to a specific antibody or T-cell receptor. The presence of antigens in the body may trigger an immune response. ...

repertoire would permit faster binding and invasion.

Taxonomy

File : Apicomplexa tree..png, 350px, Evolutionary relationships among

The ''Eimeria'' lie within the family Eimeriidae. ''Eimeria'' accounts for close to 75% of the species within this family, and it is the most specious of the genera of the

with 1,700 described species. Attempts to subdivide this large taxonomic unit into separate genera have been made. The classification of eimeriid coccidian was largely based on morphological and life cycle details. More recently, classification has been done using rDNA and

mitochondrial genes Mitochondrial DNA (mtDNA and mDNA) is the DNA located in the mitochondria organelles in a eukaryotic cell that converts chemical energy from food into adenosine triphosphate (ATP). Mitochondrial DNA is a small portion of the DNA contained in ...

, which indicate ''Eimeria'' may be

paraphyletic Paraphyly is a taxonomic term describing a grouping that consists of the grouping's last common ancestor and some but not all of its descendant lineages. The grouping is said to be paraphyletic ''with respect to'' the excluded subgroups. In co ...

to ''

Isospora ''Isospora'' is a genus of internal parasites in the subclass Coccidia. It is responsible for the condition isosporiasis, which causes acute, non-bloody diarrhoea in immunocompromised individuals. Taxonomy At least 248 species were original ...

'' and ''

Cyclospora ''Cyclospora'' is a genus of apicomplexan parasites. It includes the species ''Cyclospora cayetanensis'', the causative agent of cyclosporiasis. Members of ''Cyclospora'' are characterized as having oocysts with two sporocysts, each containing ...

'' ''Eimeria'': These species are tetrasporocystic with dizoic, nonbivalved sporocysts with or without Stieda bodies. This new genus retains the majority of the species. ''

Goussia ''Goussia'' is a taxonomic genus, first described in 1896 by Labbé, containing parasitic protists which largely target fish and amphibians as their hosts. Members of this genus are homoxenous and often reside in the gastrointestinal tract of the ...

'' (Labbe 1896): These species are tetrasporocystic, dizoic, lack Stieda bodies, and have sporocyst walls consisting of two valves joined by a longitudinal suture. This genus contains about 20 species. '' Crystallospora'' (Thelohan 1893): The species in this genus is tetrasporocystic and dizoic, and have dodecahedral sporocysts composed of two hexagonal, pyrimidal valves joined at their bases by a suture. This genus contains a single species, ''Crystallospora cristalloides'' ''

Epieimeria ''Epieimeria'' is a genus of parasitic alveaolates of the phylum Apicomplexa. The genus was created in 1981 by Dyková and Lom. Species in this genus were earlier classified as ''Eimeria''. Taxonomy Species in this genus infect fish. Descript ...

'': The species in this genus are tetrasporocystic, dizoic, possess Stieda bodies, and undergo merogony and gametogony on the lumenal surface of the intestinal tract. Three species are in this genus.

Species identification

Methods for species identification are varied and among others, include

isozyme In biochemistry, isozymes (also known as isoenzymes or more generally as multiple forms of enzymes) are enzymes that differ in amino acid sequence but catalyze the same chemical reaction. Isozymes usually have different kinetic parameters (e.g. di ...

analysis, the use of

rRNA Ribosomal ribonucleic acid (rRNA) is a type of non-coding RNA which is the primary component of ribosomes, essential to all cells. rRNA is a ribozyme which carries out protein synthesis in ribosomes. Ribosomal RNA is transcribed from ribosomal ...

and rDNA probes,

DNA Deoxyribonucleic acid (; DNA) is a polymer composed of two polynucleotide chains that coil around each other to form a double helix. The polymer carries genetic instructions for the development, functioning, growth and reproduction of al ...

assay An assay is an investigative (analytic) procedure in laboratory medicine, mining, pharmacology, environmental biology and molecular biology for qualitatively assessing or quantitatively measuring the presence, amount, or functional activity ...

s and

recombinant DNA Recombinant DNA (rDNA) molecules are DNA molecules formed by laboratory methods of genetic recombination (such as molecular cloning) that bring together genetic material from multiple sources, creating sequences that would not otherwise be fo ...

techniques. PCR has proven most useful for

outbreak In epidemiology, an outbreak is a sudden increase in occurrences of a disease when cases are in excess of normal expectancy for the location or season. It may affect a small and localized group or impact upon thousands of people across an entire ...

surveillance. Prior to these methods, species identification was based on

phenotypic In genetics, the phenotype () is the set of observable characteristics or traits of an organism. The term covers the organism's morphology (physical form and structure), its developmental processes, its biochemical and physiological propert ...

characteristics such as the site of parasite development, the oocyst structure, the host species, cross

immunity Immunity may refer to: Medicine * Immunity (medical), resistance of an organism to infection or disease * ''Immunity'' (journal), a scientific journal published by Cell Press Biology * Immune system Engineering * Radiofrequence immunity ...

and the presence of lesions. Out of these, comparing oocyst structures was the most commonly used method.

Genomics

whole genome sequencing Whole genome sequencing (WGS), also known as full genome sequencing or just genome sequencing, is the process of determining the entirety of the DNA sequence of an organism's genome at a single time. This entails sequencing all of an organism's ...

project is in progress with chosen species, ''Eimeria tenella''. The genome is about 60

megabases A base pair (bp) is a fundamental unit of double-stranded nucleic acids consisting of two nucleobases bound to each other by hydrogen bonds. They form the building blocks of the DNA double helix and contribute to the folded structure of both DNA ...

in size and has a

GC-content In molecular biology and genetics, GC-content (or guanine-cytosine content) is the percentage of nitrogenous bases in a DNA or RNA molecule that are either guanine (G) or cytosine (C). This measure indicates the proportion of G and C bases out of ...

around 53%. The 14

chromosome A chromosome is a package of DNA containing part or all of the genetic material of an organism. In most chromosomes, the very long thin DNA fibers are coated with nucleosome-forming packaging proteins; in eukaryotic cells, the most import ...

s range in size from 1 to > 6 megabases. Since 2013, the sequencing and annotation of a further six avian ''Eimeria'' species genomes is in progress.

Pathology and symptoms

Coccidiosis typically results in

diarrhoea Diarrhea (American English), also spelled diarrhoea or diarrhœa (British English), is the condition of having at least three loose, liquid, or watery bowel movements in a day. It often lasts for a few days and can result in dehydration d ...

, weight loss and

dehydration In physiology, dehydration is a lack of total body water that disrupts metabolic processes. It occurs when free water loss exceeds intake, often resulting from excessive sweating, health conditions, or inadequate consumption of water. Mild deh ...

. A combination of these factors may result in poor growth and death of the animal, particularly amongst young. Other clinical signs include

lethargy Lethargy is a state of tiredness, sleepiness, weariness, fatigue, sluggishness, or lack of energy. It can be accompanied by depression, decreased motivation, or apathy. Lethargy can be a normal response to inadequate sleep, overexertion, overw ...

, depression, and reduced normal grooming behaviour. Diarrhoea may be bloody due to

intestinal epithelium The intestinal epithelium is the single cell layer that forms the luminal surface (lining) of both the small and large intestine (colon) of the gastrointestinal tract. Composed of simple columnar epithelium its main functions are absorptio ...

dying off when a large number of oocysts and merozoites burst out of the cells. The severity of the disease is directly dependent on the number of infective ''Eimeria'' oocysts that are ingested. The

pathogenesis In pathology, pathogenesis is the process by which a disease or disorder develops. It can include factors which contribute not only to the onset of the disease or disorder, but also to its progression and maintenance. The word comes . Descript ...

of infection varies from mild to severe, and is largely dependent on the magnitude of infection. In light infections, the damage to the gut might only be minimal and be rapidly repaired as cells are rapidly replaced by the body. However, in heavy infections, it may only take two weeks for many intestinal epithelial cells to be infected with either ''Eimeria'' meronts or gametocytes. These cause the epithelial cells to burst, which causes significant damage to the intestine epithelial layer, resulting in the release of blood, fluid, and

electrolyte An electrolyte is a substance that conducts electricity through the movement of ions, but not through the movement of electrons. This includes most soluble Salt (chemistry), salts, acids, and Base (chemistry), bases, dissolved in a polar solven ...

s into the intestine.

Prevention and treatment

Good

animal husbandry Animal husbandry is the branch of agriculture concerned with animals that are raised for meat, animal fiber, fibre, milk, or other products. It includes day-to-day care, management, production, nutrition, selective breeding, and the raising ...

practices and

prophylactic Preventive healthcare, or prophylaxis, is the application of healthcare measures to prevent diseases.Hugh R. Leavell and E. Gurney Clark as "the science and art of preventing disease, prolonging life, and promoting physical and mental health a ...

application of anticoccidial drugs that target different stages of the parasite lifecycle, such as sulfonamides, ionophores and toltrazuril, are the preferred methods of disease prevention, particularly in the poultry industry. The following drugs can be used for treatment of coccidiosis in cattle: amprolium, sulfaquinoxaline, and Sulfadimidine, sulfamethazine. However, it is often more effective to prevent this disease in cattle, which can be aided by the products lasalocid, decoquinate, and monensin. There is a growing problem of drug resistance, as well as possible drug residues in the meat once the animal is butchered. As a result, other avenues of control are being explored, particularly vaccine development, although several live attenuated vaccines have been in use since the 1950s. So far, the best practice is to vaccinate the chicks once they hatch from the egg so they are immune for life. Infection with ''Eimeria'' results in life-long Immunity (medical), immunity to that particular parasite species, but does not give cross protection against other species. For these reasons, vaccines for control seem promising, of which live attenuated vaccines are most effective. However, the search for highly Immunogenicity, immunogenic

s and overcoming antigenic variation of the parasites remains a challenge. Immunity to the parasite varies depending on parasite and host species, as well as the site of invasion. T helper cell, CD4+ T cells and interferon gamma (γ) are crucial components of Innate immune system, natural immunity to infection. Humoral immunity is thought to play little role in protection, and is most likely mediated through secretory Immunoglobulin A, IgA antibodies.

Host-parasite relations

Fish

* ''Eimeria aurati'' - goldfish (''Carassius auratus'') * ''Eimeria baueri'' - crucian carp (''Carassius carassius'') * ''Eimeria lepidosirenis'' - South American lungfish (''Lepidosiren paradoxa'') * ''Eimeria leucisci'' - common barbel (''Barbus barbus bocagei'') * ''Eimeria rutili'' - European chub (''Leuciscus cephalus cabeda''), Iberian nase (''Chondrostoma polylepis polylepis'') * ''Eimeria vanasi'' - blue tilapia (''Oreochromis aureus'')

Reptiles

* ''Eimeria amphisbaeniarum'' - Mann's Amphisbaenidae, worm lizard (''Amphisbaena manni'') * ''Eimeria witcheri'' - Mann's worm lizard (''A. manni'') * ''Eimeria yemenensae'' - rock agama (''Agama yemenensis'')

Birds

* ''Eimeria acervulina'' - chicken (''Gallus gallus domesticus'') * ''Eimeria adenoeides'' - Wild turkey, turkey (''Meleagris gallopavo'') * ''Eimeria brunetti'' - chicken (''G. g. domesticus'') * ''Eimeria colchici'' - common pheasant (''Phasianus colchicus'') * ''Eimeria curvata'' - ruddy ground dove (''Columbina talpacoti''), scaled dove (''Scardafella squammata'') * ''Eimeria dispersa'' - turkey (''M. gallopavo''), bobwhite quail (''Colinus virginianus'') * ''Eimeria duodenalis'' - pheasant (''Phasianus colchicus'') * ''Eimeria fraterculae'' - Atlantic puffin (''Fratercula arctica'') * ''Eimeria gallopavonis'' - turkey (''M. gallopavo'') * ''Eimeria innocua'' - turkey (''M. gallopavo'') * ''Eimeria praecox'' - chicken (''G. g. domesticus'') * ''Eimeria maxima'' - chicken (''G. g. domesticus'') * ''Eimeria meleagridis'' - turkey (''M. gallopavo'') * ''Eimeria meleagrimitis'' - turkey (''M. gallopavo'') * ''Eimeria mitis'' - chicken (''G. g. domesticus'') * ''Eimeria muta'' - rock ptarmigan (''Lagopus muta islandorum'') * ''Eimeria necatrix'' - chicken (''G. g. domesticus'') * ''Eimeria phasiani'' - pheasant (''P. colchicus'') * ''Eimeria procera'' - grey partridges (''Perdix perdix'') * ''Eimeria purpureicephali '' - red-capped parrot (''Purpureicephalus spurius'') * ''Eimeria rjupa'' - rock ptarmigan (''L. m. islandorum'') * ''Eimeria tenella'' - chicken (''G. g. domesticus'')

Mammals

* ''Eimeria ahsata'' - goat (''Capra hircus''), sheep (''Ovis aries'') * ''Eimeria alabamensis'' - cattle (''Bos taurus'') * ''Eimeria alijevi'' - goat (''C. hircus'') * ''Eimeria aspheronica'' - goat (''C. hircus'') * ''Eimeria arloingi'' - goat (''C. hircus'') * ''Eimeria arundeli'' - common wombat (''Vombatus ursinus'') * ''Eimeria bakuensis'' - sheep (''O. aries'') * ''Eimeria bovis'' - cattle (''B. taurus'') * ''Eimeria cameli'' - camels (''Camelus bactrianus'',''Camelus dromedarius'') * ''Eimeria caprina'' - goat (''C. hircus'') * ''Eimeria caprovina'' - goat (''C. hircus'') * ''Eimeria christenseni'' - goat (''C. hircus'') * ''Eimeria clethrionomyis'' - red-backed vole (''Clethrionomys gapperi'') * ''Eimeria coecicola'' - rabbit (''Oryctolagus cuniculus'') * ''Eimeria contorta'' - mouse (''Mus musculus'') * ''Eimeria couesii'' - rice rat (''Oryzomys couesi'') * ''Eimeria crandallis'' - sheep (''O. aries'') * ''Eimeria dammahensis'' - scimitar-homed oryx (''Oryx dammah'') * ''Eimeria dowleri'' - eastern red bat (''Lasiurus borealis'') * ''Eimeria exigua'' - rabbit (''O. cuniculus'') * ''Eimeria falciformis'' - mouse (''M. musculus'') * ''Eimeria farasanii'' - mountain gazelle (''Gazella gazelle, Gazella gazelle farasani'') * ''Eimeria ferrisi'' - mouse (''M. musculus'') * ''Eimeria flavescens'' - rabbit (''O. cuniculus'') * ''Eimeria gallatii'' - red-backed vole (''C. gapperi'') * ''Eimeria granulosa'' - goat (''C. hircus'') * ''Eimeria hirci'' - goat (''C. hircus'') * ''Eimeria intestinalis'' - rabbit (''O. cuniculus'') * ''Eimeria irresidua'' - rabbit (''O. cuniculus'') * ''Eimeria intricata'' - goat (''C. hircus'') * ''Eimeria jolchijevi'' - goat (''C. hircus'') * ''Eimeria krijgsmanni'' - mouse (''M. musculus'') * ''Eimeria larimerensis'' - Uinta ground squirrel (''Spermophilus armatus'') * ''Eimeria macusaniensis'' - llamas (''Lama glama''), guanacos (''Lama guanicoe''), alpacas (''Vicugna pacos''), vicunas (''Vicugna vicugna'') * ''Eimeria magna'' - rabbit (''O. cuniculus'') * ''Eimeria marconii'' - red-backed vole (''Clethrionomys gapperi'') * ''Eimeria media'' - rabbit (''O. cuniculus'') * ''Eimeria melanuri'' - garden dormouse (''Eliomys quercinus'') * ''Eimeria myoxi'' - garden dormouse (''E. quercinus'') * ''Eimeria nagpurensis'' - rabbit (''O. cuniculus'') * ''Eimeria nieschulzi'' - brown rat (''R. norvegicus'') * ''Eimeria ninakohlyakimovae'' - goat (''C. hircus'') * ''Eimeria ovinoidalis'' - sheep (''O. aries'') * ''Eimeria pallida'' - goat (''C. hircus'') * ''Eimeria palustris'' - marsh rice rat (''Oryzomys palustris'') * ''Eimeria papillata'' - mouse (''M. musculus'') * ''Eimeria perforans'' - rabbit (''O. cuniculus'') * ''Eimeria phocae'' - Sable Island harbour seals (''Phoca vitulina'') * ''Eimeria pileata'' - red-backed vole (''Clethrionomys gapperi'') * ''Eimeria pipistrellus'' - Kuhl's pipistrelle (''Pipistrellus kuhlii'') * ''Eimeria piriformis'' - rabbit (''O. cuniculus'') * ''Eimeria prionotemni'' - Bennett's wallaby (''Macropus rufogriseus'') * ''Eimeria procyonis'' - raccoon (''Procyon lotor'') * ''Eimeria punctata'' - goat (''C. hircus'') * ''Eimeria roobroucki'' - rabbit (''O. cuniculus'') * ''Eimeria saudiensis'' - Arabian oryx (''Oryx leucoryx'') * ''Eimeria sealanderi'' - eastern red bat (''Lasiurus borealis'') * ''Eimeria separata'' - mouse (''M. musculus''), rat (''Rattus rattus'') * ''Eimeria stiedai'' - rabbit (''O. cuniculus'') * ''Eimeria ursini'' - southern hairy-nosed wombat (''Lasiorhinus latifrons'') * ''Eimeria vermiformis'' - mice (''M. musculus'') * ''Eimeria weybridgensis'' - sheep (''O. aries'') * ''Eimeria wobati'' - southern hairy-nosed wombat (''L. latifrons'') * ''Eimeria zuernii'' - cattle (''B. taurus'')

List of species

* ''Eimeria abramovi'' * ''Eimeria acervulina'' * ''Eimeria adenoides'' * ''Eimeria ahsata'' * ''Eimeria airculensis'' * ''Eimeria alabamensis'' * ''Eimeria albigulae'' * ''Eimeria alijevi'' * ''Eimeria alpacae'' * ''Eimeria amphisbaeniarum'' * ''Eimeria anatis'' * ''Eimeria anguillae'' * ''Eimeria ankarensis'' * ''Eimeria anseris'' * ''Eimeria arizonensis'' * ''Eimeria arabukosokokensis'' * ''Eimeria arnyi'' * ''Eimeria arundeli'' * ''Eimeria anseris'' * ''Eimeria arkhari'' * ''Eimeria arloingi'' * ''Eimeria aspheronica'' * ''Eimeria auburnensis'' * ''Eimeria augusta'' * ''Eimeria aurati'' * ''Eimeria aythyae'' * ''Eimeria azerbaidschanica'' * ''Eimeria bactriani'' * ''Eimeria bakuensis'' * ''Eimeria bareillyi'' * ''Eimeria baueri'' * ''Eimeria battakhi'' * ''Eimeria beckeri'' * ''Eimeria beecheyi'' * ''Eimeria berkinbaevi'' * ''Eimeria brinkmanni'' * ''Eimeria bombaynsis'' * ''Eimeria bonasae'' * ''Eimeria boschadis'' * ''Eimeria bovis'' * ''Eimeria brantae'' * ''Eimeria brasiliensis'' * ''Eimeria brevoortiana'' * ''Eimeria brinkmanni'' * ''Eimeria brunetti'' * ''Eimeria bucephalae'' * ''Eimeria bufomarini'' * ''Eimeria bukidnonensis'' * ''Eimeria burdai'' * ''Eimeria callospermophili'' * ''Eimeria californicenis'' * ''Eimeria cameli'' * ''Eimeria canadensis'' * ''Eimeria canis'' * ''Eimeria caprina'' * ''Eimeria caprovina'' * ''Eimeria carinii'' * ''Eimeria carpelli'' * ''Eimeria catostomi'' * ''Eimeria catronensis'' * ''Eimeria caviae'' * ''Eimeria cerdonis'' * ''Eimeria citelli * ''Eimeria chelydrae'' * ''Eimeria christenseni'' * ''Eimeria clarkei'' * ''Eimeria clethrionomyis'' * ''Eimeria coecicola'' * ''Eimeria colchici'' * ''Eimeria columbae'' * ''Eimeria columbarum'' * ''Eimeria contorta'' * ''Eimeria coturnicus'' * ''Eimeria couesii'' * ''Eimeria crandallis'' * ''Eimeria crassa'' * ''Eimeria curvata'' * ''Eimeria cylindrica'' * ''Eimeria cynomysis'' * ''Eimeria cyprini'' * ''Eimeria dammahensis'' * ''Eimeria danailovi'' * ''Eimeria danielle'' * ''Eimeria debliecki'' * ''Eimeria deserticola'' * ''Eimeria dispersa'' * ''Eimeria dolichotis'' * ''Eimeria dromedarii'' * ''Eimeria duszynskii'' * ''Eimeria ellipsoidalis'' * ''Eimeria elongata'' * ''Eimeria etheostomae'' * ''Eimeria eutamiae'' * ''Eimeria exigua'' * ''Eimeria falciformis'' * ''Eimeria fanthami'' * ''Eimeria farasanii'' * ''Eimeria farra'' * ''Eimeria faurei'' * ''Eimeria fernandoae'' * ''Eimeria ferrisi'' * ''Eimeria filamentifera'' * ''Eimeria franklinii'' * ''Eimeria fraterculae'' * ''Eimeria freemani'' * ''Eimeria fulva'' * ''Eimeria funduli'' * ''Eimeria gallatii'' * ''Eimeria gallopavonis'' * ''Eimeria gasterostei'' * ''Eimeria gilruthi'' * ''Eimeria glenorensis'' * ''Eimeria gokaki'' * ''Eimeria gonzalei'' * ''Eimeria gorakhpuri'' * ''Eimeria granulosa'' * ''Eimeria grenieri'' * ''Eimeria guevarai'' * ''Eimeria hagani'' * ''Eimeria haneki'' * ''Eimeria hasei'' * ''Eimeria hawkinsi'' * ''Eimeria hermani'' * ''Eimeria hindlei'' * ''Eimeria hirci'' * ''Eimeria hoffmani'' * ''Eimeria hoffmeisteri'' * ''Eimeria hybognathi'' * ''Eimeria ictaluri'' * ''Eimeria illinoisensis'' * ''Eimeria innocua'' * ''Eimeria intestinalis'' * ''Eimeria intricata'' * ''Eimeria iroquoina'' * ''Eimeria irresidua'' * ''Eimeria ivitaensis'' * ''Eimeria judoviciani'' * ''Eimeria kinsellai'' * ''Eimeria koganae'' * ''Eimeria kotlani'' * ''Eimeria krijgsmanni'' * ''Eimeria krylovi'' * ''Eimeria kunmingensis'' * ''Eimeria lagopodi'' * ''Eimeria lamae'' * ''Eimeria langebarteli'' * ''Eimeria larimerensis'' * ''Eimeria lateralis'' * ''Eimeria laureleus'' * ''Eimeria lepidosirenis'' * ''Eimeria leucisci'' * ''Eimeria ludoviciani'' * ''Eimeria macusaniensis'' * ''Eimeria magnalabia'' * ''Eimeria marconii'' * ''Eimeria maxima'' * ''Eimeria melanuri'' * ''Eimeria meleagridis'' * ''Eimeria menzbieri'' * ''Eimeria micropteri'' * ''Eimeria minasensis'' * ''Eimeria mitis'' * ''Eimeria monacis'' * ''Eimeria morainensis'' * ''Eimeria moronei'' * ''Eimeria mulardi'' * ''Eimeria muta'' * ''Eimeria myoxi'' * ''Eimeria myoxocephali'' * ''Eimeria natricis'' * ''Eimeria necatrix'' * ''Eimeria neitzi'' * ''Eimeria nieschulzi'' * ''Eimeria nigricani'' * ''Eimeria nocens'' * ''Eimeria nyroca'' * ''Eimeria ojastii'' * ''Eimeria ojibwana'' * ''Eimeria onychomysis'' * ''Eimeria oryzomysi'' * ''Eimeria oryxae'' * ''Eimeria os'' * ''Eimeria osmeri'' * ''Eimeria ovata'' * ''Eimeria ovinoidalis'' * ''Eimeria palustris'' * ''Eimeria papillata'' * ''Eimeria parvula'' * ''Eimeria pigra'' * ''Eimeria pilarensis'' * ''Eimeria pileata'' * ''Eimeria pipistrellus'' * ''Eimeria phocae'' * ''Eimeria praecox'' * ''Eimeria prionotemni'' * ''Eimeria pseudospermophili'' * ''Eimeria pulchella'' * ''Eimeria pungitii'' * ''Eimeria punonensis'' * ''Eimeria ranae'' * ''Eimeria reedi'' * ''Eimeria reichenowi'' * ''Eimeria ribarrensis'' * ''Eimeria rjupa'' * ''Eimeria rutili'' * ''Eimeria salvelini'' * ''Eimeria saitamae'' * ''Eimeria saudiensis'' * ''Eimeria separata'' * ''Eimeria schachdagica'' * ''Eimeria sevilletensis'' * ''Eimeria sinensis'' * ''Eimeria sipedon'' * ''Eimeria somateriae'' * ''Eimeria spermophili'' * ''Eimeria squali'' * ''Eimeria stiedai'' * ''Eimeria stigmosa'' * ''Eimeria striata'' * ''Eimeria subepithelialis'' * ''Eimeria surki'' * ''Eimeria tamiasciuri'' * ''Eimeria tedlai'' * ''Eimeria tenella'' * ''Eimeria truncata'' * ''Eimeria truttae'' * ''Eimeria uekii'' * ''Eimeria uniungulati'' * ''Eimeria ursini'' * ''Eimeria vilasi'' * ''Eimeria weddelli'' * ''Eimeria weybridgensis'' * ''Eimeria witcheri'' * ''Eimeria vanasi'' * ''Eimeria vermiformis'' * ''Eimeria volgensis'' * ''Eimeria wobati'' * ''Eimeria wyomingensis'' * ''Eimeria yemenensae'' * ''Eimeria yukonensis'' * ''Eimeria zuernii''

References

External links

An overview of ''Eimeria'' and coccidiosisThe Life Cycle of Coccidia
{{Authority control Apicomplexa genera Conoidasida Poultry diseases Veterinary protozoology Parasites of birds Parasites of equines