I was hoping to hear right back from you, so we could talk about Chloe.
As you know, most cats have what I call "tuna" breath. However, when there is a rotten smell that indicates an infection, a GI upset or bad bacteria. Since she has had this since she was a baby, it is possible she has a bad or broken tooth that never came in properly.
Here are things to try:
Check inside her mouth for a sore, stuck item. broken tooth or any abnormalities. Look at roof and under tongue.
If you see nothing out of the ordinary lets try a probiotic. She can have forti flora, culturelle or a half tsp of plain yogurt every day.You can also try changing her protein source. If she eats poultry try fish or beef in case its a food allergy.
Please let me know if any of these suggestions help. I will always be here for you.
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