What is a horse's normal temperature, and when should you be concerned?

Understanding the horse's temperature: essential guidelines

Horse temperature: why is this parameter essential?

The temperature is a direct indicator of a horse's state of health. Even a slight variation can reveal stress, an infection or the onset of illness. Knowing the normal values therefore makes it possible to act early and avoid complications.
The rectal temperature of a healthy adult horse generally lies between 37,5 °C and 38,2 °C, with small fluctuations depending on activity, age or time of day.

Normal values, causes and symptoms to watch for

Why is monitoring temperature crucial?

A change in temperature can indicate:

• A viral or bacterial infection
• An inflammatory reaction
• Heatstroke
• A cold snap
• A metabolic imbalance
• Significant stress (transport, training…)

Regularly monitoring this parameter makes it possible to quickly spot an anomaly and contact a veterinarian if necessary.

Causes and symptoms of an abnormal temperature

Fever (hyperthermia above 38,5 °C):

• Rapid breathing
• Dull look in the eyes
• Reduced appetite
• Significant fatigue
• Excessive sweating
• Hot, congested mucous membranes

Hypothermia (below 37 °C):

• Trembling
• A prostrate horse
• Cold extremities
• Muscle weakness
• Seeking out warmth

The causes can range from a simple seasonal infection to a more serious illness such as equine influenza, rhinopneumonitis or feverish colic.

How to correctly take a horse's temperature?

1. Use a digital rectal thermometer suited to equids.
2. Lightly lubricate the tip to avoid discomfort.
3. Stand to the side of the horse, never directly behind it.
4. Gently lift the tail and insert the thermometer 2 to 3 cm.
5. Hold it in place until the sound signal.
6. Clean the device thoroughly after use.

It is advisable to take the temperature at the same time every day, as it can naturally vary over the course of the day.

Related veterinary solutions to help a feverish horse

Care products do not replace veterinary advice but can help support the horse's comfort.

• Rehydrates after significant sweating
• Supports kidney function
• Ideal in case of heatstroke or fatigue

• Supports natural defences
• Helps horses in convalescence
• Recommended during temperature variations or infections

Frequently asked questions: FAQ on horse temperature

From what temperature should you start to worry?

An adult horse is considered to be running a fever from 38,5 °C. This threshold often indicates an inflammatory or infectious reaction.
A temperature above 39 °C calls for particular attention, especially if it is accompanied by other signs: fatigue, rapid breathing, hot mucous membranes, refusal to eat.
If the temperature exceeds 39,5 °C, a veterinarian must be contacted urgently, as this may indicate a severe infection, heatstroke or a metabolic disorder.

What should I do if my horse has a fever?

Start by isolating the horse in a calm place, free of draughts but well ventilated. Give it fresh water to prevent dehydration.
Measure its temperature every 2 to 3 hours to track how it develops. Reduce handling to limit stress.
If the fever persists for more than 12 hours, exceeds 39 °C or is accompanied by diarrhoea, coughing, colic or deep listlessness, call a veterinarian. Prompt treatment improves the prognosis.

Can temperature rise after training?

Yes, it is normal for a horse's temperature to rise slightly after exertion. The body releases heat during muscular activity.
However, this rise remains moderate and should come back down in under 30 minutes after exercise stops. A temperature that stays high may signal the onset of heatstroke or overexertion.
If the horse is still sweating heavily, shows signs of fatigue or is breathing hard several minutes after exertion, take its temperature as a precaution.

To find out more about horse temperature

• See all our products for horses
• Discover our supplements for muscle recovery in horses
• To find out more about the horse – Marronniers veterinary clinic