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Guinea Pig Weight Loss

Unless you weigh your guinea pigs fairly regularly then it can be really difficult to check for changes in weight. Weight loss or gain can be an indication of a health problem, and it can be one of only a few symptoms. The weights of your guinea pigs will change a little throughout the year, but dramatic weight loss can merit a trip to the vet. Weights vary a lot because there are big physiological differences between individuals and breeds. For example, Rex guinea pigs will often be a little larger than some of their friends.

guinea pig weights vary
Weights go up and down a little throughout the day

Once you’ve established your guinea pigs’ base weights, then guidelines are as follows:

If your guinea pig weighs less than about forty or fifty grams less than the last weigh in, this can just be part of normal fluctuations.

If your guinea pig weighs more than fifty grams less than the last weigh in, then weigh them each day and give them some more dry food just in case.

If your guinea pig weighs around one hundred grams less than the last weigh in, then this is very serious, and implies there is something seriously wrong. If this has been happening over a long period, then it’s still cause for concern, and your pet will need to see a vet immediately.

Foods For Weight Gain

If your guinea pig hasn’t been well and needs a bit of TLC, then we recommend giving them a little more dry food than usual, a little more hay, and offering them some carrots and corn which are good, dense foods for your pet.

Customer Images


Grace, 24 February 2020

Hi, my guinea pig is 4 years old. I noticed that she has suddenly losing a lot of weight. She used to be a REALLY chubby guinea pig but lately i am able to feel her hip bones and her ribs. I have been trying to give her foods like carrots now, so she will gain some weight but if it gets any worse i will take her to the vet. Not to mission that i am younger than 13 so i will need some help from my family.

Debbie, 20 October 2019

I have 2 x 9 week old guinea pigs which I got at 4 weeks old, although crumble was a little bit bigger than Cleo when we got them. Both guinea pigs eat loads of dried food, hay and fresh vegetables every day and drink plenty of water cleo hasn't grown as much as crumble and when I stroke down her back I can feel her bones. Is this normal in some Guinea pigs or should I take her to the vets. Both have good teeth, bright eyes and shiny coats and seem happy in themselves I just keep comparing sizes.

Lily, 29 July 2019

I have a guinea pig, she is 5 years old and im scared she's losing weight. I know she is naturally a small guinea pig but recently when I pick her up I've noticed that I can feel her ribs through her fur. I am now weighing her weekly and adding more fatty foods to her mix like carrot and corn. Do you think I need to take her to the vets? Thanks

Oloka, 3 May 2019

my guinea pig is a female and is 400 grams overweight what shall i do ?

Zaliah, 9 March 2019

I have 2 Guinea pigs, and I don't weigh them because my parents don't let them inside, so I can't. I don't know how much weight they have lost, but I know that their alot skinnier than usual. My Guinea pigs are A bit chubby, and they have definately lost weight. We recently bought a puppy, as my parents only bought Guinea pigs as a training pet (thinking we would only have them for a year, now it's been 5 years). Our dog is small dog, but he often jumps up on the cage and barks at them. The youngest one, Fizzles, is very scared of him, but for the oldest, Snuggles, is used to him. I'm scared that Fizzles will die, as I am very attached to my Guinea pigs. My parents don't think Guinea pigs need to go to the vet, and won't let me take them, even if I use my pocket money. I have no clue what to do, can someone please help me? It would be very appreciated.