Egg like forms of a parasite such as cryptosporidium which are infectious.

Some forms of some sporozoan eggs.

the first stage in the life cycle of a parasitic PROTOZOAN.

A part of the sporogony phase of protozoa which occurs after macro-gametes have been fertilised by micro-gametes in the intermediate host. The subsequent multiplication of cells produces an oocyst, each cell then becoming a sporozoite which is subsequently injected into the final host.