Hi
Weigh can be deceptive. I have had adult piggies that were on the sturdy side just passing 800g in their prime and one piggy who was borderline skinny at 1500g.
What you want to check re. poential overweight is actually not the absolute weight, which can vary much more individually than you'd expect but the BMI or 'heft' - i.e. whether your piggy is overweight or not. You do this by feeling around ribcage. If you can still just about feel the ribs, piggy is healthy; if you cannot feel any ribs at all, they are overweight. If you can feel every single rib clearly, then they are underweight. This method works for guinea pigs of all ages and sizes. Once you know which ballpark your own piggy's healthy weight is in, you can then use the weekly weigh-in on your kitchens for life-long health monitoring purposes to see whether their health weight is stable, creeping up or going down. Please be aware that weight is not the same throughout adulthood; the weight guide also tells you what to expect in that respect.
Our weight guide also contains plenty of practical tips on what you can do for overweight piggies:
Weight - Monitoring and Management
Please follow our very detailed diet information, which deals with all the little details as to what you can feed how much and how often - and not just for veg but for all food groups.
Too many treats and pellets but also too much veg; especially fruit and sugary root veg are ultimately life shortening and illness promoting. By turning feeding time into enrichment time with challenges and encouraging natural foraging behaviour, you can achieve actually more interactive and life-prolonging fun for both your piggies and yourself.
We strongly recommend to filter your water (bladder stone risk) and only feed 1 tablespoon of pellets per piggy per day - even no added calcium pellets contain quite a bit more calcium than the corresponding weight of the veg highest in calcium and also very little fibre when you look up the ingredients list.
By sprinkle feeding around the cage or by serving hay or veg in brown paper parcels etc. instead of bowls, you make them work. And by not distracting your piggies with plenty of empty calories, you are also encouraging them to eat more hay, which should make at least three quarters of what they eat in a day for long term health, especially dental and gut health. Veg and pellets together only replace the supplementary role of wild forage in addition to the fresh or dry grass (now hay) where they would have only rarely come across fruit etc.
A good diet can really add as much as a year or two to the average healthy life span and take it from the lower of 4-5 years to the upper end of 6-7 years or even beyond, as I know from my own piggies over the years. I now have many more piggies living to 6-8 years; even adoptees from really bad backgrounds. It is not yet too late to turn the tide.
Here are our diet and enrichment links. Please take the time to read them and if needed to bookmark them in case you want to look them up repeatedly.
Our diet guide looks at diet as a whole but then at all food groups in practical how-to detail:
Long Term Balanced General And Special Needs Guinea Pig Diets
Here are some ideas on how you can enrich your piggies' life on different levels and for all senses:
Enrichment Ideas for Guinea Pigs
All these very practical how-to guides in this post are part of our much larger helpful information resource on a very very wide range of topics, from piggy whispering and understanding behaviour to spotting signs of illness or pain and what to do in an emergency and how to care for a very ill piggy.
You may want to bookmark the link and browse, read and re-read at need as in a number of guides you will pick on different things at different levels of experience.
Comprehensive Owners' Practical and Supportive Information Collection
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