Wood shavings and biocompost as bedding material in horse stables to ensure air quality demands - the agony of choice?

Objective: The susceptibility and reaction of stabled horses to inhaled airborne pollutants is often associated with bedding materials, which have a poor hygienic status. In a field study we evaluated a new biocompost bedding material for horse stables with respect to its impact on air hygiene and compared the results to those from a reference trial with wood shavings. Methods: The study was conducted in a naturally ventilated stable. Ammonia and thermophilic actinomycetes as air hygiene parameters were measured 24 hours a day for seven days with each bedding type. Results: During the monitoring period wood shavings were associated with mean ammonia concentrations of 12.6 ppm, while biocompost caused only 5.1 ppm. On the other hand, the concentrations of airborne thermophilic actinomycetes were highest with biocompost (14,822 vs. 84 colony forming units per m3). Conclusions: This investigation clearly shows that potential advantages and disadvantages of new bedding materials have to be weighed very carefully. To ensure the well being of horses, any new bedding material must be tested very carefully before it is introduced to the market.