Fig. 1

The life cycle of Eimeria stiedae. The E. stiedae life cycle occurs both in the external environment and within the host rabbit. The oocysts are released in early, unsporulated form (Ou) by hosts in the surroundings. The oocyst undergoes sporogony by meiotic division into four sporoblasts, each of which further develops into one sporocyst. The sporulated oocysts (Os) are then consumed by rabbits, and the released sporozoites penetrate epithelial cells of the small intestine and reach the liver, where they invade liver and bile duct epithelial cells and undergo merogony. The spindle-shaped merozoites (Mz) are set free into the new epithelial cells, in which each grows similar to its parent. In a few days, fissions occur in which the young grow into two types of adults, unlike their parents, comprising male and female gametocytes (Gc). The gametocytes leave the host cell and unite (fertilization) while free in the liver. This procedure is the gametic reproduction (also known as gametogony) and results in production of new unsporulated oocysts, which will be released by the animal in the form of feces, and the life cycle begins again. The entire cycle lasts about 7 days