Pexels | Sharon Sneider

Hamsters and all rodents don't throw up. According to researchers, they apparently lack both the brains and bodies for vomiting.  

LiveScience explains the findings of a group of neuroscientists from the University of Pittsburgh Cancer Institute, which were first published in the journal PLoS One.

Curiously, hamsters, rats and mice appear to have one-way digestive systems: They don't throw up. This can make it difficult to see when they get sick from something they have eaten or medicine they have taken.


Hamsters have no gag reflex

To see if all rodents cannot vomit, the researchers analyzed members of all three major groups of rodents — the mouse-related rodents, such as mice, rats, voles and beavers; the squirrel-related rodents, such as mountain beavers; and the Ctenohystrica, such as guinea pigs and nutria. Chemicals known to cause vomiting failed to produce either retching or vomiting in any of these species.

They found rodents had bodily constraints that would limit how much they could vomit even if they could attempt it. This included reduced muscularity of the diaphragm, the thin sheet of muscle underneath the lungs, as well as a stomach that is not structured well for moving contents up the throat.


Why not vomit?

Rodents are unusual, as the vomiting reflex is widespread among mammals, seen in cats, dogs and primates. The research suggests rodents may have lost the capability to vomit because they evolved other defensive strategies to replace it. For instance, rodent responses to taste may make them better at avoiding toxins that can sicken or kill them. Rodents also eat clay when sick, which apparently can latch onto dangerous materials and keep their bodies from absorbing them.


What you can do to protect pet hamsters

Hamsters cannot expel waste products from their body which can cause huge problems for them if they ingest something that is nasty. You can minimise this risk by supervising them at all times for illness or injury and making sure that you don’t give them anything toxic.

As hamsters cannot vomit, they are more prone to choking. If a hamster overeats or eats quickly, their airways can get blocked.

Some eat very fast when they get food after a long period. Therefore, do fix a schedule of your pet’s diet and feed them at the same time each day.



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