Hi, my name is Cayla and I’ve had my two guinea pigs Yin and Yang (Two boars about 5 months old) for about two months now. Three weeks ago they were having issues with constipation and diarrhea.
As soon as I noticed I took them both to the vet and was recommended to give them canned pumpkin. I couldn’t find any that say in any stores so I ordered it. Continuing that initial day I brought them home they massively improve but have ever since stayed the stalemated at small and/or Thin poops.
I feel like I’ve tried everything from decreasing the amount of veggies they get, to increasing it, canned pumpkin, benebac,placing hay all around the cage to ensure they eat it, and so on.
None of these things have shown lasting results and I’m not sure what to do anymore

. Their behavior is still normal and their appetite is relatively the same as before. I just want my boys healthy again
Hi and welcome!
Please be aware that unlimited grass hay (timothy, orchard, meadow etc.) should make around 80% of the daily food intake. The fibre in the hay and (dog pee free) fresh grass is what keeps the gut microbiome balanced and prevents the overgrowth of bad bacteria from too much veg, especially high sugar content root veg like carrot or pumpkin. The high silica content in hay and fresh grass is also crucial in keeping the the constantly growing molars and premolars at the back of the mouth perfectly ground down since guinea pig teeth have evolved to grow at the ideal (fast) speed in relation to their hay intake. Green veg (fresh herbs, lettuce, cucumber and other leafy greens) should only make about 50g of the daily food intake (about the size of an afternoon snack) and 1 tablespoon of pellets per piggy per day is kind of in the way of a biscuit or two. Because pellets consist mainly of fillers that soften as soon as they come into contact with saliva, they cannot replace hay and should be restricted. The more closely you come in mimicking the diet guinea pigs have evolved on (i.e. lots of dry or fresh grass with a little forage of some other plants for trace elements thrown in), the healthier your piggies will be and the longer they will live.
Also be aware that fresh grass is high in vitamin C and that good quality hay also contains it, which is the reason why guinea pigs never had the need to make their own.
Here are our detailed diet recommendations with a close look at ALL food groups, including which foods are not good for them - which includes pumpkin.
Long Term Balanced General And Special Needs Guinea Pig Diets
Seeing that your diet is anything but ideal, it follows that your piggies have digestive problems. Guinea pigs don't suffer from congestion. If there are no poos, then it is from lack of food (especially hay); the same goes for diarrhea.
Please take your piggies off any fresh food and put them on a hay only diet until their digestive problems have stabilised.
Digestive Disorders: Diarrhea - Bloat - GI Stasis (No Gut Movement) And Not Eating
No or small poos means that your piggies have not eaten enough in the last day or two. Please monitor their food intalke by weighing daily at the same time on the kitchen scales. You cannot control the hay intake by eye and the poo output is lagging a crucial day or two behind, so your piggies can get quickly much worse without the up to date weight monitoring.
You may need to step in with syringe feeding top up support if the weight loss continues or the weight is not going up on the hay only diet in order to rebalance the gut microbiome. Weighing once weekly all life long and daily when they are not well is one of the most important monitoring tools to help keep your piggies healthy or get them through an illness. Opt for a hay based recovery food formula if possible to help with rebalancing the gut. Your first aim is to stabilising the weight and then gradually building it up once the poos have the right consistency on the correct fibrous food.
PS: Pumpkin is high in fibre but it is not the kind of fibre that guinea pig guts and teeth are laid out for. Your vet did have the right concept but not quite the right food group for this.
Weight - Monitoring and Management
How To Pick Up And Weigh Your Guinea Pig Safely
Complete Syringe Feeding Guide
Probiotics, Recovery Foods And Vitamin C: Overview With Product Links
Please also continue to syringe benebac to help rebalance the microbiome and look for a more piggy savvy vet you can get to.
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