⚠️ Not veterinary advice. This guide is for education on minor issues only. If you are unsure, or your animal is in pain, call your veterinarian. In an emergency, call immediately.
Fever (high temperature) in horses and donkeys
Should I call the vet?
Typical signs: Rectal temperature above normal (horse 99–101.5 °F), often with dullness, less appetite, cough or nasal discharge.
Call your vet now if you see
- Over 102 °F (101.5 donkey)
- Dull or not eating
- Stumbling, weakness or dribbling urine (EHV-1 and other neurologic disease)
- Fever with diarrhea or colic
- Swollen glands under the jaw (strangles risk)
- Recently at a show, sale or barn with new arrivals
What you can do
- Recheck with a rectal thermometer once the horse has rested in shade.
- Isolate from other horses; separate buckets, tools and hand-washing.
- Take the temperature twice daily and write it down.
- Offer fresh water and hay; rest from work.
- Give NO fever reducers unless your vet directs — they can hide the cause.
When to call the vet
Same day for any confirmed fever; immediately for call-now signs.
Normal adult vital signs (at rest)
Horse
| Vital | Normal | Concerning |
|---|---|---|
| Temperature | 99.0–101.5 °F | Over 102 °F or under 98 °F |
| Heart rate | 28–44 /min | Over 60 at rest |
| Respiration | 10–24 /min | Over 30 or labored |
| Gums / CRT | Moist pink, refill < 2 s | Pale, white, dark red, purple, tacky |
| Gut sounds | Gurgles both sides | Silent |
| Hydration | Skin pinch back in 1–2 s | Tents > 2–3 s |
Donkey
| Vital | Normal | Concerning |
|---|---|---|
| Temperature | 98.0–100.5 °F (37–38 °C) | Over 101.5 °F |
| Heart rate | 36–68 /min | Over 70 at rest |
| Respiration | 12–28 /min | Over 30 or labored |
| Gums / CRT | Moist pink, refill < 2 s | Pale, dark, tacky |
| Gut sounds | Present both sides | Silent |
| Behavior | Alert, eating | Dull or not eating = urgent (hyperlipemia risk) |
Young animals differ. Learn each animal's healthy baseline and record it.
Sources
More from Should I Call the Vet?
All 51 topics · Horse records · Donkey records · Parasites & toxic plants by state
Other horse topics
- Minor cuts & scrapes
- Hoof abscess
- Mild colic warning signs
- Thrush
- Rain rot / rain scald
- Eye irritation
- Laminitis (founder) warning signs
- Choke (esophageal obstruction)
- Mild cough / nasal discharge
- Scratches / mud fever
- Lameness / limping
- Puncture wound / nail in the foot
- Nosebleed
- Diarrhea (adult horse)
- Not eating (off feed)
- Not drinking / dehydration
- Tying-up (muscle cramping)
- Leg swelling / stocking up
- Hives (raised bumps)
- Weight loss / poor condition
- Dental problems / quidding
- Foaling problems (dystocia)
- Retained placenta (after foaling)
- Newborn foal problems
- Stumbling / neurological signs
- Snake bite
- Toxic plant eaten
- Cast horse (stuck lying down)
- Lost shoe / hoof crack
- Tail rubbing
- Vaccine reaction
- Lice / mange / skin irritation
- Heat stress
Keep every record in one place
Herd Papers keeps vaccines, Coggins, vet and farrier visits, weight and body condition for each animal, and reminds you before things come due.
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