This one is an emergency. Larger animals, particularly carnivores and omnivores, can go for a few days without eating. But rabbits are different.
Rabbits are highly evolved grass-processors.
They spend the vast majority of their day nibbling grass. Grass takes some chewing, which would grind most teeth down to nothing very quickly, but luckily for rabbits their teeth grow all the time, throughout their lives, to keep up. Rabbit teeth are like a magical grindstone that is always replacing itself.
The rabbit’s front teeth, the incisors, shouldn’t stick out at all. Bugs bunny is physically impossible. Without a pair of opposite teeth, those top incisors would grow on forever; they’d probably have reached the floor by now. Real rabbits’ incisors have an opposing pair of teeth below them to keep their growth in check, and they use these teeth to cut the ends of the grass that they nibble.
Obviously rabbits don’t tear meat so they have no teeth where our canines are. But what they do have, further back, is a row of pre-molars and molars. These are big, squarish, teeth with uneven tops, which grind against one another to turn the grass into a more digestible mush. Because they are continually worn down by grinding against one another, a rabbit’s molars will also continue to grow.
In fact, rabbits are highly evolved to eat almost all the time.
If their guts stop moving along, they are at great risk of their intestines bloating up and becoming very seriously ill. If a rabbit stops chewing for too long, their teeth will overgrow. Overgrown teeth change the shape of the rabbit’s mouth. Normally, the ‘grinding’ surface between the top and bottom molars should be quite parallel, and the food squashed and ground squarely between them.
But if the bottom and top back teeth overgrow, the rabbit is left unable to close its jaw properly at the front (imagine if your own back teeth suddenly became much longer). This is not so obvious in a rabbit because their front teeth would grow longer too, until they met. There is plenty of loose skin around the jaws to hide this, so it’s extremely difficult for an owner to spot. It’s serious, however; it permanently changes the angle of the rabbit’s mouth; the mouth is effectively wedged open by its own teeth.
A second problem can be seen if the top and bottom teeth don’t line up exactly.
Where teeth are offset, the overlapping portions will keep each other short, but the edges with no opposing surface will grow into spikes. Again, a rabbit will eat for some time with spikes sticking into its tongue. This isn’t because rabbits don’t feel the pain; it’s because it will die if it doesn’t.
Rabbits’ guts have evolved to receive a continual supply of food throughout the day.
If food does not arrive, the gut will stop moving. A rabbit’s survival mechanism is to continue to eat for as long as it can. Rabbits will keep eating if they are in agony. Owners often notice that their rabbit is ‘still eating’ and assume that it must be doing okay, but it’s simply not always true. Once the guts have stopped moving, the rabbit has not long to live.
Gut stillness, or known as “stasis” or “ileus” can be fatal very quickly.
The bacteria that live in a rabbit’s guts produce gas. But if that gas isn’t moving along the gut, it doesn’t have anywhere to go and builds up: this is the worst kind of stomach ache. Your vet can diagnose gut stasis by listening to the rabbit’s gut-sounds with a stethoscope. Those who know cattle might draw parallels with bloat, or colic in a horse.
The frustrating thing is that rabbits have evolved the ability to look extremely happy and well, even when they’re feeling the opposite.
After all, the rabbit who looks poorly is an easy victim choice for a fox. It’s therefore terribly easy to overestimate the dental health of a rabbit.
So, in conclusion, if your rabbit stops eating, it really is an emergency.
Call the vets as soon as you notice it, even if they’re closed to routines for the Corona outbreak. It’s getting more common for emergency clinics to see rabbits; word is hopefully getting out that rapid treatment can really save lives.
And what can you do if your rabbit’s eating well?
The best approach is to make sure that the diet as is good as it can be. It’s best to feed the food that rabbits evolved to consume. Which is grass; either fresh, or squashed into hard-to-chew kibbles, or as hay. Bunny guts are simply not built to last on high-calorie, low-fibre bunny-mix every day. Rabbits have evolved with an astonishingly sweet tooth but don’t let this fool you! – after all, people too will happily eat sweet diets that do us harm.
Luckily, pet-food companies are coming to accept this and many healthy rabbit-diets are available. Ask your vet for more info.