Poor litter quality in poultry houses causes hock burns, footpad dermatitis, and respiratory disease in billions of chickens, representing one of the most widespread but underrecognized welfare problems.
Litter quality represents an often-invisible welfare issue affecting the majority of the world's chickens. Birds standing on wet, ammonia-rich litter develop painful skin lesions on their feet and hocks. High ammonia concentrations cause burning of eyes and respiratory tracts. Birds with severe footpad lesions show altered gait and reduced activity, indicating pain. Because these conditions develop gradually and affect all birds equally, they are normalized within production systems even though they represent widespread, preventable suffering. Using footpad lesion scores as a welfare audit tool has proven effective at incentivizing improvements.