How much should my Guinea Pig weigh?

[Sparrow&Meadow]

I recently got two guinea pigs and am a bit concerned about ones weight. They are both around the same length, roughly 18-20cm and are believed to be around 8-10 weeks, the pet store really didn’t have a clue about their age, but their weight is drastically different. The larger one is already almost 550grams but the smaller one is barely 380grams. I can’t seem to find any sizing that includes weight, only length and don’t know if the smaller pig is underweight and the larger one is normal or the larger one is a tad on the chubby side and the smaller one is normal. Any advice?

 

[Betsy]

Hi and to the forum!

I have 5 piggies and their weight varies. I have a small boar who in at weighs 998g and his brother is larger at 1132g. The 3 sows vary in weight and they are 1195g, 1100g and 1055g they are all healthy weights. What matters more is heft. When you hold them can you feel their ribs under a small layer of fat? If so they are the correct weight for them as individual pigs.

The Importance Of Weighing - Ideal Weight / Overweight / Underweight

 

[Wiebke]

I recently got two guinea pigs and am a bit concerned about ones weight. They are both around the same length, roughly 18-20cm and are believed to be around 8-10 weeks, the pet store really didn’t have a clue about their age, but their weight is drastically different. The larger one is already almost 550grams but the smaller one is barely 380grams. I can’t seem to find any sizing that includes weight, only length and don’t know if the smaller pig is underweight and the larger one is normal or the larger one is a tad on the chubby side and the smaller one is normal. Any advice?

Hi!

Weight and size differs enormously in guinea pigs, that is why it is no good running weight charts. The important bit is not how much your piggies weigh but whether they are a good weight/size ratio in themselves and whether they have just enough flesh on their ribs ('heft'); not to much and not too little for a healthy animal. As long as your little one is continuing to put on weight in its own time and on a good diet, it has every chance of realising its genetically determined optimum weight and size by the time it reaches adulthood at 15 months old.

You will have to accept that the weight gap is going to get larger as your piggies grow until they reach the peak of their lives at around 2-3 years old.

If it is any consolation, I have had had several litter sibling pairs and trios with that kind of spread in weight, but it has not impacted pn either health or longevity. The biggest difference in weight was the 500g between sisters Nia and Nerys at the peak of their lives - but it was much smaller Nia who run the group of over 10 sows and both sisters lived to a good old age.

Here is more information on weight and feeding tips, including how you judge the heft around the ribs and how you can minimise food bullying, which is a normal part of dominance. A good hay based diet without too much veg and only very little pellets is key to optimal health and a long life - and both are much more important than the individual weight.
The Importance Of Weighing - Ideal Weight / Overweight / Underweight
Long Term Balanced General And Special Needs Guinea Pig Diets