Mushrooms Have a Future in Fighting a Fowl Parasite

By Luis Pons
December 8, 2006

Wide use of a mushroom extract to protect poultry against a major parasitic disease is now closer, thanks to an Agricultural Research Service (ARS) scientist and her South Korean colleagues.

The researchers—led by immunologist Hyun Lillehoj at the ARS Animal Parasitic Diseases Laboratory in Beltsville, Md.—developed a technique for controlling coccidiosis, which costs the world's poultry industry billions of dollars in losses annually.

The new method is the subject of a patent application. It introduces mushroom lectins to birds via injection into developing embryos, or through drinking water. Once administered, the lectins spur a protective reaction against the disease in the gut.

Coccidiosis is caused by parasites of the genus Eimeria that infect the intestinal tract and are transmitted between birds through infected feces. Often most severe in birds that are young or whose disease immunity has been weakened by other infections, the disease can cause bloody diarrhea, severe dehydration, substantial weight loss and death.

Lectins are carbohydrate-binding proteins found in animals and plants. They stimulate disease-fighting cells by binding to their sugar residues, inducing the release of potent immune-system proteins called cytokines.

Lillehoj and scientists at South Korea's Chungnam National University and Rural Resource Development Institute used lectin extracted from Fomitella fraxinea, a wood-rotting mushroom seen mostly on black locust tree stumps. They injected it into 18-day-old embryos to activate their innate immune systems and later challenged the newly hatched chicks with coccidiosis-causing parasites.

The treatment significantly protected chickens against coccidiosis-associated weight loss and reduced fecal shedding of live parasites. This particular lectin is usually prepared under less-stringent conditions than are other mushroom compounds that produce a similar effect, making its commercial production more feasible.

This research is described in a recent issue of the journal Poultry Science.

ARS is the U.S. Department of Agriculture's chief scientific research agency.