This video gives an overview of coccidiosis in chickens and shows how devastating just one bird with coccidiosis can be to an unprotected flock. While coccidiosis can occur at any age the greatest danger of infection is in chicks from four to eight weeks old. It takes around 6 days for the disease to run its course. Often there are no visible symptoms until the third and fourth days. This video does include some archival footage of chicks with coccidiosis and shows some of the symptoms of the disease as it progresses which may be upsetting to some.