About Sarcocystis in waterfowl (Rice breast)

Sarcocystis is caused by the cyst stage of a protozoan parasite, Sarcocystis spp.
Signs Of Disease
Waterfowl and carnivore hosts that are infected with sarcocysts usually appear healthy. When butchering infected ducks, cysts may be observed in the breast muscle. The cysts look like grains of rice or whitish streaks running in the direction of the muscle fibers.
Where is Disease Found?
Sarcocystosis occurs in many species of ducks throughout the United States. The parasite has been documented in many species of waterfowl in Idaho.
How Can I Protect Myself?
Waterfowl infected with cysts of Sarcocystis spp. do not pose a public health problem. Cooking meat to a temperature of 150-160oF for 15 minutes should destroy the parasite. Freezing meat to -4oF should kill the parasite.
Samples to Collect
If there is concern about this condition, contact a conservation officer or an Idaho Department of Fish and Game Regional Office. Appropriate samples can be collected for testing if deemed necessary.
Can I Eat The Meat?
Meat from an infected duck can be consumed by humans, but heavily infected muscle may not be appealing. Thorough cooking will kill the parasite. Do not feed infected meat to dogs or cats.
What is IDFG doing to help manage this disease?:

Management of sarcocystis in wild waterfowl is difficult but the disease does not pose a threat to waterfowl populations.