Eimeria stiedae
Encyclopedia
Eimeria stiedae is a species of Eimeria
that causes hepatic coccidiosis in rabbits. It was observed for the first time by Antoni van Leeuwenhoek in 1674.
to the liver, and eventually penetrate the bile duct
epithelium
, where they undergo asexual reproduction known schizogony. Rupture of the schizont consequently causes epithelial cell rupture and death. Merozoites will penetrate other cells and create more merozoites for one to several rounds. Eventually, a merozoite becomes a male microgamecyte and asexually reproduces in epithelial cells. A ruptured microgamecyte infects a cell with the female macrogamecyte and through sexual reproduction create a zygote
. The zygote develops a protective shell before expulsion in the bile excreation and then the feces as an oocyst.
, and blockage of bile ducts leading to hepatomegaly
and hence icterus. Due to liver failure, the abdomen will be distended with fluid.
Eimeria
Eimeria is a genus of Apicomplexan parasites that includes various species responsible for the poultry disease coccidiosis. The genus is named for the German zoologist Theodor Eimer...
that causes hepatic coccidiosis in rabbits. It was observed for the first time by Antoni van Leeuwenhoek in 1674.
Life cycle
The rabbits ingest sporulated oocysts. Sporulated oocysts contain four sporozoites that hatch and travel via the hepatic portal veinHepatic portal vein
The hepatic portal vein is not a true vein, because it does not conduct blood directly to the heart. It is a vessel in the abdominal cavity that drains blood from the gastrointestinal tract and spleen to capillary beds in the liver...
to the liver, and eventually penetrate the bile duct
Bile duct
A bile duct is any of a number of long tube-like structures that carry bile.Bile, required for the digestion of food, is excreted by the liver into passages that carry bile toward the hepatic duct, which joins with the cystic duct to form the common bile duct, which opens into the intestine.The...
epithelium
Epithelium
Epithelium is one of the four basic types of animal tissue, along with connective tissue, muscle tissue and nervous tissue. Epithelial tissues line the cavities and surfaces of structures throughout the body, and also form many glands. Functions of epithelial cells include secretion, selective...
, where they undergo asexual reproduction known schizogony. Rupture of the schizont consequently causes epithelial cell rupture and death. Merozoites will penetrate other cells and create more merozoites for one to several rounds. Eventually, a merozoite becomes a male microgamecyte and asexually reproduces in epithelial cells. A ruptured microgamecyte infects a cell with the female macrogamecyte and through sexual reproduction create a zygote
Zygote
A zygote , or zygocyte, is the initial cell formed when two gamete cells are joined by means of sexual reproduction. In multicellular organisms, it is the earliest developmental stage of the embryo...
. The zygote develops a protective shell before expulsion in the bile excreation and then the feces as an oocyst.
Pathogenesis and Pathology
The schizonts in the bile duct cause bile duct hyperplasiaHyperplasia
Hyperplasia means increase in number of cells/proliferation of cells. It may result in the gross enlargement of an organ and the term is sometimes mixed with benign neoplasia/ benign tumor....
, and blockage of bile ducts leading to hepatomegaly
Hepatomegaly
Hepatomegaly is the condition of having an enlarged liver. It is a nonspecific medical sign having many causes, which can broadly be broken down into infection, direct toxicity, hepatic tumours, or metabolic disorder. Often, hepatomegaly will present as an abdominal mass...
and hence icterus. Due to liver failure, the abdomen will be distended with fluid.