1. Class : Sporozoa Family : Toxoplasmatidae Genus : Toxoplasma Species : T.gondii This organism is discovered in small African rodents. Disease : Toxoplasmosis and is a zoonotic disease between human and animals.

2. Not : toxo is the arch and plasma is the form. Final host : Cat and all felids. the domestic cat is the most important for this disease. Intermediate host : man, house mice, all domestic animals and birds. Morphology : There are five main stages in the life cycle of T.gondii. although all five stages occur in cats, only two stages are found in man, other mammals and birds.

3. Oocyst:-The sporulated oocyst have two sporocyst with four sporozoites. Trophozoite (Tachyzoite) : Banana in shape or cresentic in shape 4-8µ in length, 2-3µ in breadth and one end more pointed than other, reddish spherical or ovaidal nucleus in shape and usually nearer the blunt end of the parasite. Electron microscope reveal a complex organelles, the toxonemes located at the pointed end (5-8) in number. these toxonemes support the active motility of the organism and it is ability to penetrate the cell.

4. Bradyzoite (cystozoite) : an encysted form (tissue cyst) and similar to tachyzoite, multiply slowly, affect muscle, brain, heart, liver and lung and sensitive to stomach secretion. Life cycle :- indirect, have intermediate host. Main symptom :- hydrocephalus and abortion.