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Why cant rabbits be sick?

rabbitapril

Mama Doe
My OH just asked me why are rabbits never sick.
I told him beceause they cant be, he then asked why and I could not give him the answer:oops:
Can anyone tell me why. Thanks
 
My OH just asked me why are rabbits never sick.
I told him beceause they cant be, he then asked why and I could not give him the answer:oops:
Can anyone tell me why. Thanks

They are not capable of reverse peristalsis. Which in plain english means the smooth muscle of their esophagus can only move things in one direction. which is toward the stomach.

:wave:

(typed from an article regarding rabbit health which i've now closed the page and can't find again :roll:)
 
I see, I am familiar with the word peristalsis, I did not know it couldnt work in reverse in rabbits, thanks.
But I now wonder why:shock:
 
Rabbits have no 'vomit centre' in their brain, so their brain isn't physically capable of 'telling' their stomach to vomit :)
 
Rabbitapril, we are so alike asking "Why?"

Yes they can't do reverse peristalsis at the top end. There's a muscular valve where the oesophagus meets the stomach, & it's so strong they can't even burp either!

Risking a guess I'm amazed by how good an instinct some of our pet buns have for the types of food they need. In the wild, the babies will also learn what to eat by watching the adults. (My bun learned an incredible amount of behaviour by watching me, & copying :oops:) They have 26 different types of tastebuds (We have 4) & an incredibly acute sense of smell. I suspect that instinct & learning combine, so they don't eat poisons in the wild. So they don't need to be sick.
Again in the wild there's a huge variety of plants they can eat to settle down an "iffy tummy" before it causes big problems.

The lower gut is absolutely amazing & I think unique in domestic animals. It does reverse peristalsis on a timed basis, to produce waste poops & caecs.
 
Thanks Thumps, when I read how they can't be sick, I did wonder why nature had made them like this.
So that must be why bunnies are so prone to tummy problems, for our pet buns maybe it would be better if they could be sick:?
Now another question, does the same apply to guinea pigs?
 
Rabbits are classified as post-gastric (hind gut fermentors) as are horses. The muscular valve at the point of stomach and oesophagus Thumps referred to is the pyloric sphincter which is the same in horses who also cannot vomit. I think rabbits are the only hind gut fermentors that produce caecotropes for re-ingestion but I'm not certain. Some other animals in this classification are elephants, zebras, koalas, wombats and possums.
 
Apparently the vomit centre in the brain is either totally absent or poorly developed - so they may 'have' a vomit centre but it is pretty much redundant.
 
Rabbitapril, we are so alike asking "Why?"

Yes they can't do reverse peristalsis at the top end. There's a muscular valve where the oesophagus meets the stomach, & it's so strong they can't even burp either!

Risking a guess I'm amazed by how good an instinct some of our pet buns have for the types of food they need. In the wild, the babies will also learn what to eat by watching the adults. (My bun learned an incredible amount of behaviour by watching me, & copying :oops:) They have 26 different types of tastebuds (We have 4) & an incredibly acute sense of smell. I suspect that instinct & learning combine, so they don't eat poisons in the wild. So they don't need to be sick.
Again in the wild there's a huge variety of plants they can eat to settle down an "iffy tummy" before it causes big problems.

The lower gut is absolutely amazing & I think unique in domestic animals. It does reverse peristalsis on a timed basis, to produce waste poops & caecs.

Two peristaltic movements in opposite directions - blimmin' incredible if you ask me! :D
 
Buns dont have muscles in there digestive tract like humans. They cant push there food along the same way our muscles do thats why they need constant hay/grass they have to swallow at least 420 times per day to keep pushing the food through the system thats why its an emergency if they stop eating as the food just blocks up.
 
Buns dont have muscles in there digestive tract like humans. They cant push there food along the same way our muscles do thats why they need constant hay/grass they have to swallow at least 420 times per day to keep pushing the food through the system thats why its an emergency if they stop eating as the food just blocks up.

:?

Er i'm not sure where you read that but yes rabbits DO have smooth muscle lining their digestive tract just like we do, and it is controlled by the autonomic nervous system just like ours is. :wave:

ETA in fact, if you watch very closely when your rabbit is lying prone you can see the waves of smooth muscle performing peristalsis.
 
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I can confirm that buns are definately dependant on the smooth muscle, & intact nerve supply to their gut for peristalsis, because a few like mine, have poor innervation, sometimes called megacolon, or dysautonomia.
They could not repond to the gut motility agents used for stasis otherwise.
Dietary fiber is an important natural stimulant of peristalsis. (Also a bit like us)
They have to keep eating because their diet has to be so high in indigestable fiber, & relatively low in nutrients to keep the caecal micro organisms healthy.

I can also confirm that the gut can be slowed down or paralysed by toxins which temporarily block the nerves to the muscle & are made by overgrowth of the "wrong" bacteria in the gut.
Unlike humans buns have a relatively thin muscle layer around the stomach.

I can also confirm that buns have a poorly developed, but present vomitting center in the brain. When I asked Marie whether buns could feel nausea although they couldn't vomit, she thought it perfectly possible.

It risk of hijacking but in the same area, I would like to know why buns seem to need to make chewing movements without macerating the oral contents to initiate smooth swallowing.
I cite "chewing movements" to swallow caecals but the caecals are intact in their membrane in the stomach contents at pm. My own bun drinks silently when he makes chewing movements, but when he needs a dental & doesn't chew, swallowing is accompanied by gulps & sounds quite difficult in comparison.

Still calling Rodney vet or Marie Kubiac
 
The main factor is the pyloric sphincter (in fact rabbits can't even burp properly, hence why gas bloat occurs).
The vomition centre isn't well developed but still there. Using anti-nausea meds in head tilt bunnies appears to improve their behaviour (particularly appetite) so there is likely to be nausea similar to humans with vertigo and the right circuiting to respond even if not as well developed.
Beyond that, I think there has been better explanation already!

Thumps - The mouth movement triggers saliva release so presumably food is swallowed more easily?? Not sure about the drinking other than the jaw needs to move to allow the tongue to move in a regular fashion.
 
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