Horses are warm-blooded mammals and regulate their body temperature through a process called thermoregulation, which balances heat generation and heat loss. They produce heat through metabolic processes, especially in the hindgut via bacterial fermentation of forage.
- Forage-Based Diet: Horses should be fed a forage-based diet, with 2-2.5% of their body weight in good quality forage per day, especially during colder months to maintain their energy levels and body temperature. For an average 500kg horse this is 10-12.5kg a day.
- Thermoneutral Zone: Horses can maintain their body temperature comfortably in temperatures ranging from 5°C to 25°C. Below 0°C, they require additional forage to support increased metabolic heat production.
- Differences Between Horse and Human Temperature Zones: The Thermoneutral Zone for humans is much higher than for horses (14.8°C – 24.5°C), so owners should avoid assuming their horse feels cold just because they do.
- Natural Insulation: Horses have a thick winter coat consisting of two layers (guard hairs and undercoat) that provide insulation and waterproofing, making them well-adapted to winter conditions.
- Rugging Considerations: Over-rugging can lead to overheating and sweat buildup, which may cause skin infections and weight loss. Rugging decisions should consider the horse’s natural ability to regulate its temperature.
- Overweight Horses: Winter is a good opportunity for overweight horses to lose weight by utilising their natural fat stores to stay warm. Rugging may not always be necessary, particularly for unclipped horses.
- Shelter and Forage in Cold Weather: Healthy, unclipped, un-rugged horses can withstand cold temperatures if provided with sufficient forage and shelter. However, wet and cold conditions can be more challenging for them to manage.