As this week is rabbit awareness week let’s start with some fun digestive facts about rabbits!
Fun fact one:
Despite their small, furry appearance a rabbit’s digestive system greatly resembles that of a…
…horse! Like horses, rabbits are hind-gut fermenters, meaning they have an organ called the caecum which functions like the rumen of a cow to digest fibre. Instead of being at the beginning of the digestive tract, like the cow, it’s at the end. The caecum is full of special microbes that break down and digest fibre, which is the main energy source for rabbits. Healthy microbial populations in the caecum are critical for proper digestion and optimal gut health.
Fun fact two:
Rabbits pass two sorts of faeces. Regular dry pellets that look like familiar ‘rabbit poo’, and a second type of soft faeces called a caecotroph. These are passed at night and contain many nutrients such as amino acids, vitamins and minerals. We don’t see these caecotrophs as rabbits eat them directly from the anus. This may sound gross but by doing this, nutrients produced by fermentation of food which is indigestible to us, in the caecum, are captured by the small intestine on the second pass around. This adaptation is pretty awesome, and makes them the ultimate recyclers!
Fun fact three:
Rabbits cannot vomit. So best to avoid feeding them anything toxic!
What has this got to do with mucky bottoms?
It’s often a problem with this process of caecotrophy that causes these wetter faeces to linger around your bunny’s bottom, causing a ‘mucky bottom’. Often, owners mistake this for diarrhoea. True diarrhoea is uncommon in adult bunnies.
What can affect the caecotrophs?
If your rabbit is overweight they may actually not be able to turn around and eat the caecotrophs. Instead, they stick in the fur around the bottom. Obesity will also put strain on joints and organs, just like in people. A common reason for obesity is overfeeding of the nutrition-packed pellet food. Your rabbit should only have one tablespoon of nuggets per day (twice daily for bunnies over 3.5kg), one handful of green veg, and their own body size (not weight!) in hay/grass. Apparently, a good diet makes caecotrophs better tasting! According to the PDSA PAW Report 2018 (a sort of “state of the nation” but for pets), 77% of rabbit owners don’t know their pet’s current weight or body condition score. Often, owners are unaware that their pet’s weight is an issue. Arrange a check up with your vet to find out if your bunny’s weight is healthy.
Rabbits can get arthritis just like we can. If it occurs in the spine then they may physically not be able to reach around and eat the caecotrophs. Rabbits still maintain a prey animal mentality, where hiding pain is essential for survival. They will not show signs of pain like we do, and instead hide it well. If your bunny has a mucky bottom or you see them eating the caecotrophs off the floor, this may be a sign of pain. If your bunny has had a previous injury then you may need to watch for this too.
Interestingly, rabbits teeth grow continuously. It is vital they have enough hay/forage in their diet to keep the teeth worn down. If they are not worn sufficiently, painful spurs form on their molars causing pain where they rub against the tongue or cheek. The pain leads to a reluctance to eat, which only compounds the issue of the ever-growing teeth. Rabbits with dental pain will also be reluctant to eat caecotrophs which leads to a mucky bottom. Your vet will be able to check on your bunny’s dental health.
Foods rich in sugars or starch such as; beans, peas, corn, bananas, grapes, cucumbers, apples, strawberries, pears, tomatoes and carrots should only be fed as treats and in small amounts. Too much may cause the caecotrophs to be improperly formed and sloppy. They will stick to the fur around the bottom and not be eaten. While nuggets are a vital part of the diet, they are densely packed with nutrients and often overfed. Excessive amounts not only means they will gain weight, and be too full to eat hay, but also means they produce lots of caecotrophs. Not all of them will be eaten and the remainder will stick around the bottom causing issues. Muesli food should not be used, as rabbits can selectively leave some parts, missing out on certain nutrients.
What are the consequences of a dirty bottom?
We’ve talked about how health issues can cause the build up of faeces around your bunny’s bottom. This can also have knock on effects.
Having faeces caked on the fur is uncomfortable. The skin may become chapped and infected. A veterinary check is essential to try to work out the underlying reasons for poor caecotrophy and how to address them. They may prescribe creams, painkillers and other medications to manage the skin. In the meantime, if your bunny is getting a build up of faeces, daily bathing and drying is essential.
Flystrike occurs when blowflies, attracted by faeces or wounds, lay eggs, resulting in maggots which will eat away at flesh. It’s a truly awful condition that makes many veterinary professionals, despite our strong stomachs, falter. As maggots can hide undiscovered under fur and faeces, and rabbits tend to hide pain well, flystrike is often not discovered until too late. Many rabbits need to be euthanased. Those that are treatable can face a long and difficult recovery. It’s important to keep your rabbit’s bottom clean, checking it daily, or several times a day in warm weather. It is also important to clean your bunny’s environment often. If you see signs of fly eggs or maggots you need to get your rabbit to the vet immediately. Application of a flystrike preventative such as Rearguard can prevent eggs laid on the rabbit from hatching into maggots.