Welcome to Justanswer! I am Dr. Altman and happy to assist you both today!
Unfortunately if there is an underlying process going on (food allergy, inflammatory bowel disease to name a few) then the gi tract will be more susceptible to giardia, bacterial overgrowth, clostridia, campylobacter which can result in further gi issues. Bear is a bit young for these but it is still a possibility that there is an underlying process for Bear causing the diarrhea.
So that leaves you with a few options
1.) Doing a food allergy trial. Surprisingly most food allergies are to the protein in diets not the grains so using a food that is specifically for this purpose, which is where the proteins are broken down beyond the point where the body recognizes the protein as beef, chicken, fish and monitor for improvement in signs. These foods include: royal canin h/p (hydrolyzed protein), hill's z/d ultra
-During the food trial he cannot have anything besides these diets and this can be a two week trial. So no treats nor other foods. This is the best way to rule out food allergies
2.) Starting a probiotic from your veterinarian such as proviable which is a probiotic that has no meat based products in it (I am unsure which one you are using, prostora and fortiflora are both meat based probiotics).
3.) Unfortunately if the diarrhea does not change or becomes looser throughout the day then the recommendation is going to be more aggressive. Abdominal ultrasound to evaluate the thickness of the intestinal tract layers throughout and possible endoscopy/ colonoscopy to evaluate and biopsy the layers of the intestinal tract with a camera and without an invasive surgery
4.) Lastly, there is a blood test to ensure the pancreas is not part of the problem and this is a specific test called a tli, folate, cobalamin level that is sent to a lab in Texas to rule out this condition
I have a food allergy dog and this can be quite a challenging situation. She is on the royal canin h/p formula longterm and whenever she gets anything else she breaks with loose stools :(
I hope this information makes sense but please let me know if you have any additional questions or concerns I can assist with!
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