Rats Do Hiccup
Please enjoy sweet Chancy (“Chance-ee”) licking me and hiccuping happily, as she tries to save me from the evil bandaid. This video was filmed in January 2009, when she was about 2 years old. Chancy lived to age 4 years, 3 months, and hiccuped from age 8 weeks, up to the sad morning when we had our last deep cuddle before I took her to be euthanized because a benign tumor affected her quality of life. Chancy hiccuped thousands of times and never suffered from active respiratory disease.
Yes, Rats Hiccup.
At the bottom of this gallery are videos of healthy rats hiccuping.
In general, all mammals hiccup. From, http://www.wisegeek.com/do-animals-get-hiccups.htm:
"Hiccups can happen in any animal that has a diaphragm as the separator between the organs of breathing and the organs of digestion, and this includes all mammals. Other warm-blooded animals get hiccups just as humans do, when the diaphragm is somehow irritated, but because the physiology of animals is different from that of humans, the hiccups they produce won’t necessarily sound the same. ... When other animals get hiccups, the acoustic properties of their organs affect how these disruptions sound....
"...While the causes of hiccups vary, most cases arise from a disruption or irritation of the diaphragm, a thin sheet of muscle below the lungs. The irritated diaphragm sends a message to the brain via the vagus and phrenic nerves that causes the muscles of the diaphragm and other organs associated with breathing to contract spasmodically. This convulsion forces air into the lungs, and this push of air forces the air passage to close rapidly at its end, the epiglottis."
Here's Bonny Bon-Bon hiccuping in full glory:
Important medical note: Hiccuping in rats should be assessed as part of a general medical exam, in particular for respiratory symptoms. If your pet rat hiccups, please assess for respiratory illness. Here is one page with helpful information on Mycoplasma pulmonis.
This gallery has videos of pet rats hiccuping. I have shown them to a nationally known exotics vet, who had never seen the behavior and acknowledged he did not know the cause of hiccuping.
Does your rat hiccup and do you have a video of him or her doing it? Let me know and perhaps we can add it to this gallery.
Hiccuping is a complicated subject because one explanation is that the hiccuping is a symptom of illness, specifically the incurable bacteria, Myco pulmonis, with which most domesticated Norway rats are infected from birth. However, it is not scientifically proven that hiccups in rats are myco-based. Below is an email exchange copied with permission (from me and Lindsay Pulman) concerning this topic, and edited for general posting.
First some of my thoughts, based on my personal experience and not on any professional medical background regarding rats or hiccuping:
I believe hiccups can be related to myco, but not necessarily. I was having a conversation with Lindsay Pulman about this in regards to someone else who asked, and she offered some information which is posted at the bottom here.
For myself, I believe Debbie D thinks hiccups are 100% myco-related, and if I recall correctly, she mainly concludes this because when she worked at a lab, she never saw lab rats hiccuping. (Logic being, lab rats are pathogen-free, they don't hiccup; rats with myco do hiccup, therefore hiccuping is myco-related.)
However, we know of folks, Lindsay included, who own multiply-tested pathogen free rats, who *do* hiccup. So, if both myco-infected rats and myco-free rats hiccup, then hiccuping cannot be proof of myco. I have a feeling Debbie wouldn't have seen lab rats hiccuping because it's primarily a positive/happy/excitement-generated behavior (although also could be anger-generated) and rats in the lab may not have the best environment to stimulate hiccuping. At their adopted human homes, though, they hiccup!
However, a rat with active myco symptoms may hiccup - so in this case you're seeing both kinds of symptoms/behaviors at the same time. So hiccuping does warrant checking out the health status of your rat.
My rats hiccup with positive excitement (read: happiness) or negative excitement (read: mad as heck when one's personal coconut is stolen from under one).
Here's Lindsay's more thorough medical explanation:
Some people think that all of that type of hiccuping action is caused by a reverse sneeze. I do not believe that in my experience. I have seen rats rapidly sneeze, in a staccato pattern, ejecting air (expiration) but it sounds just like what it is, a sneeze. I have seen rats get a nasal plug and they will snort inwards, like some people do, to dislodge the plug. But, that to me is obvious as to what it is - and does not resemble what I call hiccups.
All of my rats have hiccuped, at one time or another, some more than others. And, the hiccups sound just like our hiccups, only the squeak is higher in pitch, and it is more rapid. It is made on inspiration only, is very very regular, and after a short period of time, disappears. Mine hiccup usually on food treat stimulation or more commonly, after they have just been medicated orally with meds in syrup from a syringe. The sound is from the vocal cords, to my ears, not a whistle from a narrowed nasal passage. I know that sound well, and I am convinced that rats do hiccup just like we do.
The trick is to tell the difference.
I doubt that the person who owns the rat will be able to make that determination without help. I wish I was there. Perhaps if she has a really good rat vet, that vet could listen to the chest, listen carefully to the nasal passages, and make a determination that, at that particular time, the rat is healthy and free of clinical signs, or, may have an upper or lower respiratory problem. Undoubtedly the rat will not hiccup while at the vets ...
I think that if there is any doubt, though, that the rat should be put on a course of Baytril 15 mg/kg twice daily and doxycycline 5 mg/kg twice daily, for 3 weeks minimum. If it is, indeed, the start of nasal inflammation and narrowing due to Myco, then that will help beat back the infection. If it is not, and is really hiccups, the meds will not hurt the rat.
One thing I disagree with is using long term doxy alone for Myco control. In my experience, both Baytril and doxy together are much more effective at controlling Myco, than doxy alone. It won't hurt, but won't be nearly as effective as the combo.
The advice for antibiotics is a good one. Always start antibiotics just in case. I would do both Baytril and doxy, not just doxy.
Tell the owner not to be sad, but to be proactive and address finding out what it is, and to treat her with both drugs, because it may help (if it is, indeed Myco) and it won't hurt (if it is not).
And, in my opinion, rats do hiccup (stimulation of the vagal nerve that runs down through the chest and into the abdomen, by various things, can cause hiccups).
I believe totally that rats hiccup as humans do, I think that the physiological reasons are similar, and also that the physical eruptions are similar. The reason rats can hiccup and eat is because of the separation of the pharynx and larynx - rats are obligate nose breathers and can breathe and swallow at the same time. And they can vocalize up through their nose versus through the open mouth, since the vocal cords are so much more separate from the pharynx than ours are. That makes perfect sense to me that they can eat and hiccup, and they can brux and hiccup, and that the sound comes out of the nose - most (but not all) of the vocalizations come up through the nasal passages, with the mouth closed. So the hiccups, which are sounds made by the vocal cords by the rapid and uncontrolled inspiration of air, would not come out of the mouth.
I do not know why rats can control their hiccups, but humans can too, if you stop and think about it - you start hiccuping, and then go through whatever magic manipulations work for you to get rid of them - 10 quick swallows of water, or holding your breath, breathing in and out of a bag, a teaspoon of sugar in the mouth while pinching the earlobe - gosh, so many ways to get rid of them.
I also know that SPF rats hiccup (I have 12 of them now, continually testing negative for Myco, and they hiccup about the same as my other pet store rats do) and this is a powerful argument that these are really hiccups and not Myco related. I think there's a solid argument that rats hiccup, but that they also can sneeze rapidly, and may also reverse sneeze rapidly - discerning the difference is the challenge. With nasal issues, there is usually a ‘congestion’ or ‘wetness’ or ‘plugged’ tone to the noise. With hiccups, they are clear, clean squeaks. Vocal cord noises.”
Below, Melody and Chancy, who are nestled in fleece that is warming under a lamp, erupt in happy hiccups. :)