Effects of Bedding Material on Equine Lower Airway Inflammation: Comparison of Two Different Peat Beddings, Wood Pellet and Straw Pellet

Research output: Conference materialsPosterpeer-review


Due to the high prevalence of respiratory diseases, especially equine asthma amongst horses worldwide and the major role of air hygiene on the pathophysiology of these diseases, the effects of bedding material on air quality are of importance. The objective of our study was to investigate the effects of four different bedding materials on respiratory signs, tracheal mucus score, and on tracheal wash and bronchoalveolar lavage cytology in healthy adult horses.
The study design was a prospective controlled study, and the subjects were healthy adult riding school horses (n = 32) from a single stable in Ypäjä, southwestern Findland. Peat was used as a reference bedding material. Wood pellet, straw pellet and loosely stored peat (Peat 2) were compared to peat packed in plastic covered bales (Peat 1). Lower airway endoscopy and sampling (tracheal wash (TW) and bronchoalveolar lavage fluid (BALF)) for cytological examination were performed after each 35-day bedding period.
The tracheal mucus score (P = 0.014) and respiratory rate (P = 0.026) were higher during the straw pellet- period compared to the Peat 1- period. The respiratory rate was lower during the wood pellet- period compared to the Peat 1- period (P = 0.004). The TW neutrophil percentage during the straw pellet- period was higher compared to the Peat 1- period (P = 0.0003). The BALF neutrophil percentage was higher during the straw pellet- period (P = 0.005) and during the Peat 2- period compared to the Peat 1- period (P = 0.04).
We conclude that baled peat (Peat 1) caused less lower airway inflammation compared to straw pellet and loosely stored peat (Peat 2). There was no difference between Peat 1 and wood pellet.
Based on these preliminary findings, compared to straw pellets and loosely stored peat, baled peat bedding caused less neutrophil percentage in the lower airway of healthy horses. There was no significant difference between baled peat and wood pellets in the inflammatory cell proportions. The results of this study support the initial hypotheses of peat being a suitable option for horse stable bedding material and superior to straw pellets when considering equine airway health. The manufacturing process and storage of peat bedding may play a role in its hygienic quality, as the baled peat product was superior to the loosely stored peat. The information gained from this study may assist veterinarians and horse owners in selecting bedding materials, especially for horses suffering from respiratory diseases. More research on the effect of bedding materials in horses with different respiratory conditions is warranted. As the use of peat may not be a long-term solution due to future availability of it, the focus should be turned to other bedding materials that share similar properties with peat.

Original languageEnglish
Publication statusPublished - 8 Dec 2021
MoE publication typeNot Eligible
EventEläinlääkäripäivät 2021 -
Duration: 8 Dec 202110 Dec 2021


ConferenceEläinlääkäripäivät 2021

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