Evaluating microbiome patterns, microbial species, and leg health associated with reused litter in a commercial broiler barn

SUMMARY: Poultry litter amendments are commonly used to mitigate ammonia levels by binding and reducing ammonia volatilization in poultry housing, but there are concerns that litter amendments may impact broiler health. The goal of our study is to characterize the effect of an organic-certified diatomaceous earth litter amendment on the microbial content of the litter, and the gastrointestinal microbiome and leg health of fast-growing broilers. The study was carried out over a 2-yr period involving 5 consecutive flocks housed in a barn, where one half of the barn received the litter amendment while the other half served as a control. Key health indicators such as gastrointestinal microbiome diversity, and leg health were monitored. The findings suggest that the organic litter amendment, while not significantly altering the bacterial counts in the litter, may offer benefits in improving broiler wellbeing. This is evidenced by differences in footpad dermatitis and hock burn scores between the treated and control groups, highlighting the potential of such amendments not only in managing ammonia levels but also in promoting animal health. This study provides valuable insights into the applied implications of using an organic diatomaceous earth amendment in a poultry facility, indicating a positive impact on bird welfare without altering the microbial balance within the litter.