Researchers tested whether edible mushroom fruiting bodies could be used as animal feed for chickens. They found that chickens fed diets containing oyster mushroom (Pleurotus sapidus) had reduced growth and lower nutrient absorption compared to control chickens. While mushroom-based feed appeared to increase beneficial gut bacteria diversity, it ultimately impaired overall chicken performance, suggesting mushroom fruiting bodies are not suitable as a primary feed component for commercial poultry production.