Dippity pig syndrome (DPS), often listed as erythema multiforme, is a sudden, very painful skin flare in pet pigs. Red, weeping streaks appear across the lower back, the hind end "dips" or sinks, and the pig may scream when touched. It usually passes on its own within a few days, but it hurts, so call your vet, especially for a first episode or if your pig is in pain, won't eat or isn't improving.
What Is Dippity Pig Syndrome?
Dippity pig syndrome, also called bleeding back, is a skin condition seen mostly in pet mini pigs and potbellied pigs. Erythema multiforme is a type of inflammatory skin reaction, and whether DPS is the same thing is still debated. A 2023 study in PLOS ONE calls DPS a clinical term for signs vets may diagnose as acute dermatitis or erythema multiforme; some researchers think the two are one condition, others think DPS only resembles it.
Vets have described it in potbellied pigs since at least the 1990s, yet it has barely been studied and there is no cure. What we know comes from that one study, pet pig vets and pet pig associations, so expect a few honest "we don't know yet" answers below.
Signs of Dippity Pig Syndrome
It comes on fast. A pig can go from normal to unable to stand within hours, and the skin changes can show up within minutes. Look for:
- Red, wet streaks across the back. They sit over the lower back and rump, sometimes partway up the spine, and usually run side to side rather than head to tail. They weep fluid that can run down the sides and may ooze some blood.
- A dipping or sinking hind end. The back legs buckle or splay, and some pigs pull themselves along with their front legs. The front legs are usually fine.
- An arched, hunched back with the tail clamped down.
- Pain when the back end is touched. Squealing or screaming, restlessness, pacing and not settling to rest.
- A grumpy pig. A pig in this much pain may run off or snap at you. It isn't personal.
Appetite varies. Some pigs keep eating and drinking lying down, while a Florida pet pig vet describes fever, dullness and going off feed in many cases.
Nobody is sure yet whether the hind end drops because of the pain alone or because the nerves to the back legs are briefly affected.
How Long Does Dippity Pig Last?
Usually a few days. Sources range from about 1 to 10 days:
Source | What it says |
|---|---|
PLOS ONE study (2023) | Pigs recover within 2-4 days; sores crust over by day 2 and heal in a few days to 2 weeks without scarring |
North American Pet Pig Association | Signs typically last 24-72 hours |
Springhill Equine Veterinary Clinic (pet pig service) | About 7-10 days on average |
A pig can have one episode or several over its life. Most cases are in pigs between about 4 months and 4 years old; older pigs are affected less often.
What Causes Dippity Pig Syndrome?
Nobody knows yet. The leading idea is that stress sets it off. Triggers that pet pig vets and associations list include:
- travel, shows and vet visits
- new pigs, new people or houseguests
- changes in routine, diet or surroundings
- thunderstorms
- heat, sudden temperature swings and illness
- a female pig's heat cycle, or farrowing (giving birth)
Sun exposure has also been suggested, and owners report more cases in spring and summer.
Human erythema multiforme is often linked to the herpes simplex virus, so researchers went looking for viruses. The PLOS ONE team tested eight affected Göttingen minipigs and found some pig viruses, including a pig herpesvirus in one animal, but found the same viruses in healthy pigs and no virus particles in the sore skin. A 2022 study of sows with an erythema multiforme-like rash also found pig herpesviruses without proving they caused it. The researchers think several factors probably work together. There's no good evidence that it runs in certain breeds.
What to Do if Your Pig Has Dippity Pig Syndrome
Call your vet, especially for a first episode or if your pig is in pain, won't eat or isn't improving. DPS passes on its own, but the PLOS ONE authors say affected pigs should always get pain relief. Your vet can check your pig's temperature, make sure it really is DPS and choose a pain medicine that is safe for pigs.
Don't give human pain relievers or allergy pills on your own. Springhill's pig vet points out that aspirin, for one, is not approved for pigs. Use only what your vet prescribes, at the dose they set.
While you wait, keep things calm. The North American Pet Pig Association recommends a quiet, dark place, rest, reassurance and plenty of water:
- Move your pig to a quiet, dim room at a comfortable temperature, out of the sun.
- Keep noise low. Soft music and a calm voice help some pigs.
- Keep other pets and visitors away so your pig can rest.
- Put water within easy reach.
- Don't touch or rub the sore area, and don't pick at scabs later. Gentle reassurance is fine if your pig wants it.
- If your pig normally potties outside, put down puppy pads or a pee mat so it doesn't have to walk.
When to Call the Vet Right Away
Call now, or go to an emergency vet who sees pigs, if your pig:
- has a fever, or seems dull and unresponsive. DPS can bring a fever, but so do look-alikes such as erysipelas; Springhill's pig vet says to call for anything over 103°F
- stops eating or drinking
- can't stand at all, or the front legs are weak too (DPS usually spares them, so think of other causes)
- has raised pink or purple diamond-shaped patches, or purplish ears, snout or belly
- is in pain that isn't easing, or is getting worse after a day or two instead of better
And call any time you're simply worried. No good vet will mind.
What Else Could It Be?
Pig skin turns red for many reasons, and some are serious. The big one to rule out is swine erysipelas, a bacterial infection that causes high fever, a pig that won't get up and classic diamond-shaped skin patches. The UK's Animal and Plant Health Agency pig experts call it one of the most common diagnoses in pet and smallholder pigs, and the Merck Veterinary Manual notes that it usually responds to prompt treatment. Guessing is risky: a Mississippi State University vet school case report describes a pet potbellied pig with a red rash and a very high fever that turned out to have erysipelas and died.
Other look-alikes include sunburn in white-skinned pigs, mange and serious infections such as classical swine fever. Redness away from the back points away from DPS.
Can You Prevent Dippity Pig?
There is no vaccine and no proven prevention. Pet pig vets recommend cutting down on stress, which in practice means:
- keep your pig's routine steady and make changes slowly
- introduce new people, pigs and places gradually
- give shade, especially to light-skinned pigs, which also prevents sunburn
Our writer Sharmaine knows this one first-hand. Her mini pig Scout had her first episode at about three months old, the first time people stayed overnight. Sharmaine suspected the sleepover, so she slowly got Scout used to visitors. Scout has had three or four episodes since and is now a hit with guests. One owner's experience, not proof, but it fits what vets say about stress.
What to Expect Afterward
Most pigs are back to their usual selves within a few days, sometimes sooner. The sores crust over and the scabs fall off on their own, usually without scars. Leave them alone.
Your pig may keep its distance or dislike being touched on the back for a few days. Give it time and its favorite routine, and the bond comes back. If the skin isn't healing or your pig isn't back to normal, book a recheck.
Originally written by Sharmaine. Updated by the I Love Veterinary editorial team.
Sources
- Jhelum H, et al. First virological and pathological study of Göttingen Minipigs with Dippity Pig Syndrome (DPS). PLOS ONE, 2023
- Halecker S, et al. Virological Characterization of Pigs with Erythema Multiforme. Microorganisms, 2022
- North American Pet Pig Association: Dippity Pig Syndrome
- Springhill Equine Veterinary Clinic: Dippity Pig
- Merck Veterinary Manual: Swine Erysipelas
- APHA Pig Expert Group: Disease in smallholder and pet pigs
- Mississippi State University CVM: Diamonds and Pearl, a swine erysipelas case in a pet potbellied pig (2019)
This article is for general information and is not a substitute for advice from your veterinarian.
