Pet Rats/Pet Rat


QUESTION: So I have had my rat for about a year and a half now and she is so skinny. She used to be a healthy size, but now I can feel all her bones, especially her ribs. I feed her consistently and she eats really well and stops when she is not hungry. She has a lot of energy and loves to explore and hop around. The only problem is her weight.

ANSWER: Hi Cassidy,
What do you feed her? Have you checked her teeth to make sure they are normal?

A common cause of weight loss in rats is a respiratory infection. What is her breathing like?

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QUESTION: Her teeth look healthy to me. I feed her Kaytee Fortidiet Health Support Diet. I'm not sure how to check her breathing.

ANSWER: Normally, when a rat is at rest, you can barely see the breathing, just a little movement in the flank area. When they are asleep you have to really look hard to see if they are breathing. Can you easily see her breathing? Does she make any noise when she breathes?

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QUESTION: She doesn't look like she has any trouble breathing. When she drinks I don't see her struggling to take in air through her nose and I haven't noticed any noise when she breathes.

Okay, well you can try giving her a calorie supplement.

The best supplement for rats who aren’t eating well or who are losing weight is powdered soy infant formula from the grocery store.  (The liquid form goes bad too fast.)  The brand doesn’t matter because they’re all about the same (Wal-mart's store brand is cheapest).  They contain pretty much all the nutrients a baby needs, and they are 50% fat, so they help put the weight back on them fast.

Mix a little of the powder in water, pedialyte, or juice.  You can mix it as thick or as thin as you need to.  Thick encourages intake of nutrients and can be fed off your finger, thin encourages intake of fluids.  Most rats love it and will lick it out of a little dish. You can also give it with an eyedropper or syringe. You can also soak or mix ground rat blocks in it.

The infant formula is nearly a complete diet for rats. The only nutrients the formula is short on for rats is the B vitamins.  When giving the formula longterm, add enough liquid vitamin B complex supplement to supply 1 mcg of B12 to each scoop of formula, or you can add ¼ Tablespoon of nutritional yeast (available at health food stores) per scoop of powder.  If your rat doesn’t like it, try adding a tiny drop of vanilla extract or other flavoring.  If that doesn’t work, try adding some whipped cream or ice cream.

If the formula is pretty much all your rat is eating, give one scoop of the powder in the morning and another scoop at night.  One scoop a day is enough if the rat is eating other foods.

I highly recommend my Rat Health Care booklet which includes this and a lot more helpful info.  You can find more info about the booklet on my website at on the Books page.

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Debbie Ducommun


I can answer any questions about pet rats, but you will probably be able find answers to simple questions more quickly on my website at If you have a life-threatening emergency you can try calling me at 530-899-0605. I am not usually on the computer on the weekend.


I have been "The Rat Lady" since 1985 and am recognized as one of the world's experts on pet rats. I have 3 published books and already answer lots of questions about rats daily.

President of Rat Assistance & Teaching Society

I am a monthly columnist for Pet Business magazine, and my writing has appeared in other magazines. I have 3 published books.

BA in Animal Behavior

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