Suitability of biocompost as a bedding material for stabled horses: respiratory hygiene and management practicalities.
Authors: Seedorf J, Schröder M, Köhler L, Hartung J
Journal: Equine veterinary journal
Summary
# Editorial Summary: Biocompost as Equine Bedding — A Cautionary Finding Researchers in Germany conducted a week-long investigation comparing air quality in a naturally ventilated stable bedded with biocompost versus wood shavings, measuring ammonia, dust, endotoxins, and various bacterial and fungal populations alongside direct observation of four horses. Whilst biocompost substantially reduced ammonia, inhalable dust, endotoxin and fungal concentrations compared to wood shavings—potentially beneficial for some aspects of respiratory hygiene—it harboured thermophilic actinomycetes at 639 times the concentration found in wood shavings, along with significantly elevated mesophilic bacteria and actinomycetes. The biocompost's higher moisture content and tendency to cling to the horses' coats presented additional management challenges, though the animals showed no overt clinical signs during the trial period. For practitioners considering bedding alternatives to reduce ammonia and dust exposure, biocompost's apparent respiratory benefits must be weighed against the substantially increased risk of thermophilic actinomycete-related airway disease, particularly in horses with predisposition to recurrent airway obstruction; the authors conclude the material is unsuitable for stable use and emphasise the critical need for rigorous pre-market safety testing of novel bedding substrates.
Read the full abstract on PubMed
Practical Takeaways
- •Do not use biocompost as stable bedding for horses; the high thermophilic actinomycete content presents a respiratory health risk despite lower dust and ammonia levels
- •Wood shavings remain the better choice for respiratory health in stabled horses, even though they generate higher dust and ammonia concentrations—the thermophilic actinomycete risk with biocompost outweighs those advantages
- •Any new bedding material must be thoroughly tested for microbial content and respiratory irritants before introducing it to your stable, as animal behaviour observations alone are insufficient to assess safety
Key Findings
- •Ammonia, dust, endotoxins, and fungi concentrations were significantly higher with wood shavings than biocompost bedding
- •Thermophilic actinomycetes concentration was 639 times higher in biocompost than wood shavings, agents that elicit recurrent airway obstruction
- •Mesophilic bacteria, mesophilic actinomycetes, and thermophilic actinomycetes were highest with biocompost bedding
- •No significant differences in lying-down behaviour between bedding types, and horses showed no clinical signs during trials despite biocompost adhesion to hair coat