Thank you for the additional information.
I am glad to hear she has been wormed,since gastrointestinal worms can be a very common cause of diarrhea in young cats. That said, I would double check what was used because there are a lot of wormers on the market (vet and otherwise) but the majority don't do both tapeworms (this white rice looking worm segment) and roundworms/hookworms both. Spot on wise, I would suspect Droncit would have been used since this one of the few that comes in this type of preparation and covers both worm groups. That said, I would advise double checking this.
Now, if we can rule out worms, we do still have a number of agents that can manifest as diarrhea in the otherwise healthy cat. Most commonly we see these changes associated with bacteria, viruses (ie. panleukopenia, corona virus), metabolic imbalances (more so in older cats), parasites (not just worms but also giardia, coccidia
, and tritrichomonas), and nutritional causes. Since you have a recently made a gradual diet switch, we will place nutritional issues lower on our list.
The next step to getting to the bottom of what is causing her chronic diarrhea would be to discuss with your vet the potential to submit a fresh fecal sample to the lab. Analysis of a fecal sample is a very good way of cutting to the chase and making a dent in our list of potential causative agents. The lab will be able to check for common parasitic agents (those aforementioned that wouldn't have responded to the wormer), corona virus, and bacterial causes of diarrhea of the cat. As well, the bacterial culture will be tested to determine which antibiotics they are sensitive to. And if this is a bacterial or parasitic complaint, knowing what the causative agent is will help you treat it effectively and clear this abnormal stool.
I hope this information is helpful.
Please let me know if you have any further questions.
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