7 days post-infection of Eimeria tenella showing recently-fertilized macrogametocytes (now immature occysts) in vacuolated areas with prominent nuclei. 1000x7  7 days post-infection with E. tenella showing a young oocyst, just below an older oocyst with formed cyst wall (irregular body due to dehydration in the slide preparation) and a microgametocyte (with peripheral granules/microgametes) to its right.  The oocysts pass out in the feces where they litter the ground and are infectious to other birds after a day of sporulation.  It is highly contagious and poultry are routinely fed with drug-spiked food to prevent epidemics.  The drugs are referred to as coccidiostats. 1000x