Thank you for your question regarding your 5 month old Westie girl Livy who has a gel like substance in her stool. Good on you for following up on this with your vet already. It sounds like she has already been diagnosed with having Giardia, and thankfully she is near the end of her treatment now. Giardia often causes ongoing diarrhea, and it can often appear a green color and very smelly. Hopefully the stool itself has firmed up now as she is nearing the end of her course. It would be best to take in a fresh stool sample a few days after her last lot of the Giardia meds. Here your vet can send this away to ensure she is giardia negative, as well as check for other underlying issues such as intestinal worms or an intestinal infection like campylobacter or sensitivity control.
The gel in the stool is most likely mucus. This can commonly occur in puppies for a number of reasons, but the most common reason is due to a diet change. Given your girl has had giardia and has been on giardia meds, it could even just be due to this. Hopefully your vet has made a suggestion for the diet she should be on. If not, then try and stick with something nice and bland. A dry kibble with the primary ingredients of chicken and rice (or something similar), or a wet/canned equivalent would be fine. You could even try (just for a few days as it won't be balanced for your puppy's growth), cooked, boneless skinless chicken breast and boiled white rice made from home. This may be enough to settle some colitis (inflammation of the colon) and stop the mucus.
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