Coccidiosis is a disease that infects the intestinal tract by parasitic protozoa called coccidia. Coccidia cause severe scours in goat kids and can be fatal. In adult animals it causes the development of scar tissues and reduces nutrient absorption through intestines. Older animals may not exhibit clinical signs of coccidiosis; however, animals exposed to coccidiosis become unthrifty and efficiency of gain drops drastically.

To prevent coccidiosis in kids, provide medicated feed when they are weaned or when they arrive at your farm. Do not crowd and concentrate goat kids in a limited area and keep their living quarters as dry as possible. Coccidia are single-cell protozoa that live and multiply in the intestinal wall. Basic knowledge of the life cycle of the organism can help in preventive management procedures.

Two species are important pathogens in goats, Eimeria ninakohlyakimovae and E. arlongi. These parasites live and grow within cells lining the gastrointestinal tract of the goat. The egg (oocyst) passes through the feces of the infected goat. At this stage, oocysts are harmless. Oocysts go through a developmental state (sporulation) in the environment, which lasts for about two to three days and requires moisture, oxygen and warm conditions. Sporulated oocysts are very resistant to the environment and disinfectants and, if swallowed by the kids, will cause infection.

In the intestines, sporozites are released and rapidly penetrate the intestinal cells. In the cells, coccidia pass through several multiplication stages and form large schizonts and then meronts, which grow many times their original size and form merozoites. Merozoites can invade other cells and reproduce for many generations, then differentiate into male and female gametes and produce oocysts within the cell. Oocysts can pass through feces, completing the life cycle in two to three weeks.

Coccidia at the developmental stage destroy numerous intestinal cells and permanently damage the absorption capacity of the wall. Potentially, one oocyst ingested produces millions of oocysts, which will pass through feces two to three weeks later and destroy millions of cells of the small intestines causing the goat to become unthrifty.