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This could come as a big surprise to some people, but rodents can make wonderful pets, especially for children who might not be ready for a larger, longer-lived animal.

As a rule, rodents are friendly – even affectionate, intelligent and easily tamed. (Think of Mickey Mouse or Stuart Little.) Like other animals (including humans), they should have regular care, attention and exercise to stay healthy and happy.

Although they don’t require vaccinations, you should still bring your new rodent to us when you first get it so we can do an examination for any signs of disease or other problems. At the same time, we’ll advise you on proper feeding, housing, handling and day-to-day care.

A bit of background – Rodents owe their name (from the Latin verb rodere) to their universal propensity to gnaw. Using their front teeth (incisors), rodents are continually munching away on plant material (they’re strictly vegetarians [or herbivores]). Because those teeth never stop growing through a rodent’s live span, they can become overgrown. The best way to prevent this problem is by feeding your rodent its correct diet and providing pieces of wood or specially designed toys for it to chew on.

Selecting a healthy rodent – Chances are, you’ll either be buying your pet rodent in a pet shop or, if you’re after a particular type, from a breeder. In both cases, take a close look around the pen or cage to make sure it’s clean and well looked after.

Also ensure the animals you’re choosing from have been weaned from their mother(s). Then pick one that is active, moves easily and breathes quietly and evenly without any coughing, wheezing or sneezing. It should appear bright and healthy with no discharge from the eyes, nose and mouth at one end and no staining – a sign of diarrhoea – at the other. And those teeth should be clean and straight, not overgrown or broken.

Male or female? – With the exception of rats, which have obvious testicles at birth, determing the sex of young rodents can be pretty difficult. In mice the genital opening and anal opening are farther apart in males than females. Although the male’s scrotum is retracted inside the abdomen, the nipples of females are fairly obvious.

If you have a guinea pig, lay it on its back in the palm of your hand and gently press on either side of the genital opening. If it’s a male, its penis should protrude. Like mice, male guinea pigs also have a greater distance between their genital and anal openings than females.

One, two, three, four or more? – While there are no rules saying you can’t keep mice, rats and guinea pigs on their own, they are naturally very social animals and enjoy company. They are also far more interesting to watch as they interact and play together. Be aware, however, that rabbits carry Bordatella bronchiseptica, which causes pneumonia in guinea pigs. And because rats carry Streptobacillus, a bacterium fatal to mice, the two should never be housed together.

Of course, some of this interaction will inevitably lead to new litters. On a very regular basis since females are ready to conceive shortly after giving birth. Aside from many more mouths to feed, this also means overcrowding. To prevent these problems if you already have both males and females, we suggest having potential dads desexed. If you are just starting out, why not select a group of females who will live together harmoniously?

Common diseases – The problems we see most often with pet rodents include respiratory diseases, anorexia and lethargy, overgrown teeth and tumours. The best way to help prevent such problems is by maintaining good hygiene, a proper diet and a stress-free environment.

Respiratory disease. If you notice discharges from your pet’s nose and eyes, chances are it has developed a respiratory disease, which isn’t all that uncommon in rodents. However, wheezing, coughing and breathing with its mouth open are signs of pneumonia. Further symptoms can be loss of appetite and lethargy. Hopefully, you’ll have brought your pet to us before this happens so we can begin immediate treatment with antibiotics. Because all pet rodents are sensitive to certain antibiotics, possibly leading to an upset stomach and diarrhoea, even death, you should leave the choice of medication to us. And never use antibiotics left over from another pet.

As mentioned above, guinea pigs are susceptible to a bacterium called bordatella which causes respiratory disease that can be fatal. For mice and rats, the dangerous bacterium is mycoplasma.

The best way to prevent serious respiratory infections is by providing a clean, dry and warm environment and avoiding overcrowding.

Anorexia and lethargy. Not eating (anorexia) and lethargy (lack of energy) are symptoms rather than diseases, but they’re the most common signs that your pet could be ill. Whether the problem is pneumonia, cancer, kidney or liver failure should be left to us. The sooner we can make a diagnosis the sooner we can start the correct treatment and the better your pet’s chances of recovery.

Overgrown teeth. As we pointed out earlier, rodent teeth continue to grow throughout their lives. If they don’t wear down naturally, they won’t meet properly, usually causing your pet to drool. Eventually it may stop eating.

If your pet’s teeth have grown too long, they’ll need trimming. While we can do this using nail clippers, teeth sometimes break resulting in infection. The alternative is using a rotating burr while the animal is under anaesthesia. In some cases the best choice will be removal of the teeth.

Once again an ounce of prevention is better than a pound of cure. Providing your pet with blocks of wood to chew should be all it takes to naturally keep teeth the right length.

Tumours. Generally, cancer in rodents shows up as tumours on the body, commonly associated with the mammaries. Because the mammary glands in rats and mice extend along the backs and sides, breast cancer can appear as a lump just about anywhere on the body.

We can remove tumours surgically under anaesthesia, but this is best carried out while the tumour is still small.

To find more about the rodents we see most often at PAH, just click Mice & Rats and/or Guinea Pigs.