A wild rice byproduct as an alternative to wood sawdust for equine bedding: a pilot study evaluating effects on stall air quality.

Overview

• This study evaluated the use of wild rice straw (WRS), a byproduct from cultivated wild rice production, as an alternative to traditional wood sawdust (WS) for horse stall bedding.
• The research compared environmental factors such as water absorption, muck production, particulate matter, and ammonia levels between the two bedding materials to determine if WRS is a viable substitute.

Background and Purpose

• Minnesota produces a significant amount of cultivated wild rice, resulting in leftover straw material (WRS) after harvesting.
• Wood sawdust (WS) is commonly used for horse bedding but may have costs and sustainability issues.
• The study aimed to assess whether WRS can serve as an effective alternative bedding that maintains or improves stall air quality and cleanliness.

Study Design and Methods

• A crossover design involved 4 horses housed overnight in stalls bedded with either WRS or WS for 5 days, then switched to the other bedding type for an additional 5 days.
• Variables measured included:
  • Water Absorptive Capacity (WAC): How much liquid the bedding can absorb within 24 hours.
  • Muck Production: Amount of soiled bedding accumulated daily.
  • Suspended Particulate Matter (PM): Dust and airborne particles within stalls.
  • Ammonia Concentrations: Levels of ammonia, which can impact respiratory health.

Key Findings

• Water Absorptive Capacity:
  • Wood sawdust absorbed significantly more water than wild rice straw (P < 0.05).
• Ammonia Concentrations:
  • Stalls bedded with wild rice straw had significantly lower ammonia levels compared to those with sawdust (P < 0.05).
• Muck Production:
  • No significant difference was observed between WRS and WS bedding types (P > 0.05).
• Suspended Particulate Matter:
  • PM levels were similar between wild rice straw and wood sawdust bedded stalls (P > 0.05).

Conclusions and Implications

• Wild rice straw, although less absorbent than wood sawdust, effectively controlled ammonia levels and did not increase dust or muck compared to sawdust.
• WRS could be considered a suitable alternative equine bedding material, especially as it adds value to an agricultural byproduct that might otherwise be wasted.
• Using WRS may benefit horse stall air quality by reducing ammonia exposure, potentially improving equine respiratory health.
• Further research with larger sample sizes and over longer periods may help confirm these findings and evaluate economic and practical aspects of WRS as bedding.