Pet owners all know that one of the most unpleasant things is to experience their animals vomit. Not only because of the mess and foul smell, but because it's upsetting to see their companion sick. If people don't like to vomit it may be much worse for animals who are not quite sure of what is going on. Of course, dogs sometimes attempt to clean up their own mess, which is a unpleasant event of its own. However, there are some animals who do not have the ability to vomit.
Horses are one of the animals that cannot vomit. They cannot vomit, because their body does not allow them to. The valve muscle is powerful and prevents it, but also the esophagus and stomach meet at an angle which aids in the valve cutting off when the stomach is bloated. The formation of their body keeps them from throwing up. This is something that humans do not have to worry about.
Rats and small animals like hamsters can also not vomit. Rats, like horses, have a barrier beween their stomach and esophagus. It disables the esophageal muscle from opening the barrier. In the process of vomiting animals contract two muscles of the diaphragm independently and rats are unable to do that. Their brains do not have the proper control to allow them to vomit. One would think that an animal like a rat would need to vomit with what they eat sometimes, but they simply cannot.
Rabbits are also known for not being able to vomit. Similar to the digestive system of horses and rats, they also do not have the capabilities to vomit. This is cause for a major problem in rabbits, because they often ingest fur in the way that cats do. Cats are able to throw up hairballs to save themselves from other issues, but because rabbits cannot throw up, they do not have this safety.
It's odd to think that the ability to vomit is actually a good thing. Humans and other animals often save themselves from other pains by vomiting things that should not be ingested. Many people do not realize that there are animals that cannot vomit, because it is something that comes natural to them. We begin vomiting as babies and continue doing so our whole life. These animals do not have the option, and it is hoped that they are never in a situation where they would need to.
