What is EC (e. Cuniculi) in house rabbits?

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E. Cuniculi is a parasite that can cause head tilt, paralysis and even death in pet rabbits.

It can be a terrifying thing to witness in your rabbit.

I know, because two of mine have had bad cases of it. So I’m going to start by saying that both of them survived it, despite one of them having a very, very severe case.

Daisy is currently still in recovery from her EC episode. We struggled to find resources for how to deal with a rabbit that rolls everywhere, so I’ve written a full post on how we roll-proofed her enclosure and made sure she was fed and watered safely.

The recovery timelines vary MASSIVELY from rabbit to rabbit. Daisy was in the rolling stage for many weeks but was eating and drinking really well, so we were happy to continue with her rehabilitation.

Is EC common in house rabbits?

Yes, very.

In fact, around 50% of rabbits test positive for E. Cunuculi antibodies, suggesting they’ve been exposed to the parasite.

EC can be carried from mother to offspring too, so whilst I always recommend you have your rabbits spayed and don’t breed them, it’s even more important if the mother has tested positive for EC.

Since Daisy is Holly’s baby, it’s highly likely that Holly also has the EC pathogen, but at the moment she’s not presenting any symptoms.

I’m glad because she has a far more delicate disposition than Daisy – she’s like a rabbit version of Mrs Bennett.

Holly was treated at the same time as Daisy, and we’ll probably give her a course of Panacur every few months just in cases.

What is EC in rabbits?

EC (Encephalitozoon cuniculi) is a parasite (it’s actually a fungus) that affects many different mammals. It can damage the nervous system and cause neurological issues and organ failure. In severe cases it’s fatal.

EC can be passed to humans from rabbits, but usually only in people with weak immune systems.

Whilst we ensured we were washing our hands after handling our rabbits and cleaning them out, we weren’t worried about contracting EC.

The actual causes of EC are unclear, but it can be exacerbated when rabbits are stressed and kept in cramped, unclean conditions. It can be passed from rabbit to rabbit through their urine.

How can I tell if my rabbit has EC?

As I mentioned before, around 50% of pet rabbits carry the EC pathogen. You can get a blood test to determine if your rabbit has the pathogen BUT I wouldn’t recommend it. It’s not going to tell you much.

We’ve had two rabbits that had bad cases of EC, and each was in a bonded pair – one with her mother, the other with her brother. It’s highly likely (like a 99% chance) that all four rabbits had the EC parasite present at some point in their lives, but only two had attacks.

George never showed any sign of EC and he lived until he was around 11.

We knew Daisy was high risk when we adopted her. She’d been presenting with head tilt at the rescue and was treated there. Chances are she’ll need to have a course of medication every few months for the rest of her life.

What are the symptoms of an EC episode in rabbits?

We first noticed that Daisy’s eyes were tracking to one side. It was a very slight difference that we might not have noticed we were not in lockdown due to Coronavirus.

From a distance it just looked like her head was pulling to the left, then she’d pull it back to centre, and then off it would go again.

When we watched her though, it was her left eye that was moving, and she was moving her head to compensate. She also stopped eating her pellet food, though she made up the calories with hay and veggies.

It’s worth mentioned that this eye-tracking behaviour is common behaviour in red-eyed bunnies. It ALWAYS worth checking with a vet, but if you have a REW (red-eyed white) eye tracking is not unusual.

It was at this point that we called the vet, who prescribed drugs for both rabbits. The situation worsened, and Daisy has to spend 36 hours under 24 hour vet care. She couldn’t stop rolling over, since the parasite had affected her balance, and she developed a severe head tilt.

The vet wanted to put her to sleep since most rabbits will stop eating, go into painful GI stasis, and die. We were pretty sure she wouldn’t make it. It was about as bad as head tilt gets.

Fortunately, Daisy still ate like a horse, and though she needed to to have her food and water brought to her.

She didn’t need to be syringe fed at any point, though I believe the veterinary nurses did give her critical care just to ensure she was getting the right vitamins.

We brought her home when there was nothing more the vets could do – we just had to wait for the rolling to stop. There was a large chance the head tilt would remain, so it was just a case of keeping her safe, fed, and allow her to get used to her new view of the world.

What is the treatment for rabbits with EC?

There’s a drug called Panacur that’s used to treat EC. You can get it on Amazon, though I would definitely see a vet first, since EC is only one cause of head tilt.

When Daisy was rolling so badly that she had to be contained in a padded box, I think the vet gave her relaxants so she wasn’t exhausted.

The rolling is a symptom, and whilst it looks AWFUL and is scary for your rabbit (it really looks like they’re having a fit), it isn’t dangerous unless your rabbit hurts themselves.

It’s basically a severe loss of balance. Daisy was put in a blanket-filled box between two cushions so she was propped up.

Once Daisy was finished with the 28-day course of Pancur, she was still rolling, but wasn’t being medicated, since the rolling isn’t something you can medicate…

…In the UK anyway.

Facebook recommended a drug that can help with dizziness, but our vet wouldn’t prescribe it since it’s not authorised for use on rabbits in the UK (there are actually very few rabbit-specific drugs – most are for dogs/cats).

I can’t remember what it’s called, but it’s prescribed for humans to help with travel sickness in the US. In the UK it’s used for schizophrenia.

Isn’t the way medication works incredible?

Rehabilitating a rabbit with head tilt/rolling

This part can be stressful, because you’re treating symptoms and rehabbing. There aren’t any drugs (at least that we could get) that can help. It’s a case of time, patience, and care.

I have a full post on this BUT there are a few important things to remember:

  • Don’t pick your rabbit up

Leave them on the floor and don’t touch them if you can help it, because it’s very disorientating for them, and can set them off rolling again.

Daisy also rolled when she was angry. We’d try not to laugh but her little angry face rolling around the pen was funny. Angry rolls are higher and faster than just normal over-balance ones.

  • Make sure they’re safe

Keep them in a small pen and pad the edges. Towels will do, but we found that pipe insulation zip tied to the x-pen was a great low-cost solution. You’ll also need to switch to a water bottle over a bowl.

I was terrified Daisy wouldn’t know how to use one, but she did. We offered her a bowl at the beginning, but she’d inevitably start to roll and end up soaked.

If you’re worried your rabbit isn’t getting enough water, offer them a bowl or bottle every couple of hours.

Daisy drank A LOT so I was worried about her kidneys, but this calmed down. I think I was just hyper aware of everything she was doing so I worried more.

We experimented with various boxes in the beginning, since bright light can be stressful to rabbits with EC, but I was scared she’d get stuck behind them and get stressed.

Instead, you can peg a towel over the top of the pen so there’s a bit of a hidey-hole. You could even line the sides of part of the pen with cardboard as a kind of fake box.

  • Keep them clean

Daisy couldn’t use a litter box – 1. because it’s probably the last thing on her mind, what with all the rolling, and 2. because she’d end up rolling in litter and ending up covered in it.

We came up with a great solution (after numerous battles with wee-covered rabbits wrapped in chewed puppy pads) – get a piece of flexible plastic the size of the bottom of the pen (ideally only about 1 – 1.5 metre square) and put enough puppy pads on it to cover it (we use two).

Then wrap the whole thing in a washable blanket. We have two towels and one blanket that we use, and then we just wash the towel and change the pads every other day.

Here’s Daisy on the day we brought her home from the vet:

Can my rabbit die from EC?

Yes, unfortunately.

Some vets recommend putting rabbits to sleep when they hit the fully-rolling stage – our vet gently suggested it.

Sometimes this is necessary BUT I recommend staying optimistic as long as your rabbit is eating, drinking, and pain-free.

Your rabbit may have a permanent head tilt, but they can get used to that.

If your rabbit gets kidney failure, or paralysed back legs, I’d go with vet recommendations, or ask for the opinion of a local rabbit rescue – try to find someone with a similar experience. We were lucky that Daisy never stopped eating, and is recovering (very) slowly but surely.

My experience with EC in rabbits

I’ve covered most of this, but there are a few things that happened to us that I’ll share here. There isn’t very much information on recovery for head tilt bunnies, so I’ll share a few points:

  • There’s a Facebook group called Help for Head Tilt Hoppers that my boyfriend joined. Some of the members shared timeline stuff that really helped. It can be a really slow process
  • It doesn’t matter how long your rabbit takes to recover, as long as they’re still eating and seem happy enough.

A lot of factors will come into play. Daisy went through a stage of learning how to roll to where she wanted to be and seemed to give up on trying to walk. She’s currently pretty good at hopping, but we still have rolly days (2 months later)

  • Daisy and Holly unbonded.

We don’t know if they’ll rebond, but if we have to keep them separate, so be it.

They didn’t have the strongest bond to begin with (two girls can be a tricky combo), since Daisy always used to try to be dominant and hump her mum.

It was actually Daisy that tried to attack Holly when Holly tried to sniff her through the bars of the xpen.

Currently, Daisy is far too disabled to even consider a bonding session.


Holly has blossomed. She was extremely timid when we got her, and she really came out of her shell when Daisy was at the vets, and she seems to love being a single bun.

The girls can still see one another, though we’ve put a perspex sheet between their two pens because I’m scared we’ll end up with ears/noses bitten. They’re a little gentler with each other now, but it’s not something we’re going to rush.

Here they are chilling ‘together’:

  • Daisy’s condition fluctuated

She never lost a tonne of weight, but she lost a bit. All the rolling made her coat greasy, but she’s started to gain weight and her coat is looking much better. We kept an eye on her ‘down’ eye and it’s ok – check for redness since they can easily poke them in the eye with hay.

  • Daisy likes attention more

She always did, but she especially does now. She likes to be chatted to (she’ll come over and rest her head on the pipe insulation) and she like nose rubs. We still avoid picking her up (it makes her mad and she starts rolling) apart from when we put her in a box so we can change her bedding.

  • Your rabbit will flick poop everywhere

This gets better over time as it’s caused by the rolling, but our vacuum has been through the ringer.

  • It can feel like one step forward, three steps back

The vet warned us of this. Some rabbits can be 100% ok in a week. It’s been months for us and Daisy has improved a tonne but she still rolls sometimes and has her head on at 90 degrees.

Final thoughts on EC in house rabbits

It’s a horrible disease, but it isn’t always a death sentence. Make sure your vet is at least little rabbit savvy, and ask for a second opinion if they recommend putting your rabbit to sleep if they’re still eating and drinking (unless they’re in kidney failure I suppose).

The vet stay cost us £345 which is…a lot. However, since we knew Daisy’s history when we adopted her, we could plan.

I know a lot of people would never consider spending that much on a rabbit. I wonder if that’s why the vet edged us towards putting her to sleep.

It was important to us that we gave Daisy a chance. She’s a Netherland dwarf, and they’re a pretty feisty breed. If there had been a moment when we thought that it was too much for her, we’d have 100% reconsidered our decision.

Every time she rolled, she looked surprised, not frightened, every time a bag rustled, her little ears would prick up (well, across, because of the head tilt), and now she’s climbing about on the pipe insulation like a little mountain goat.

We’ve started taking her out of her pen to run around the living room, and she’s loved it. We don’t know how much more she’ll improve – she maybe be somewhat disabled forever – but if she’s happy so are we.

4 thoughts on “What is EC (e. Cuniculi) in house rabbits?”

  1. Hi,

    Did you continue with any treatment in the future? My rabbit Fudge has had EC twice and i believe is experiencing a mild symptoms again, seems to be when he is stressed. Would you recommend panacur for 28 days or just the 9? Thank you

    • Our vet advised us to do 2 or 3 full treatments (so 28 days) a year, and our other rabbits (who doesn’t have symptoms) gets a 9 day course at the same time. Personally I’d do the full 28, but it’s best to consult a vet

  2. Our bunny has mites.. The vet said probably from the dogs. He is 5 never had a problem before. Head tilt on antibiotics. We are so worried.

    • Urgh it’s so horrible to watch them struggle. I’m sure the meds will stop the worst, but even mild head tilt can seem so bad. It often gets worse before it gets better, so don’t panic if that happens.

      If he starts rolling use rolled up towels to help support him. We found keeping them in a box helps support, and we offered her water every hour or so in case she was too tired to go looking for it herself.

      Daisy still has a tilted head but she’s 100% fine apart from looking a little weird!


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