First off, it is very important that you consider the type of diet that you are feeding your pet. Certain types of food can cause more gas production and fouler smelling stools than others. If you are feeding canned or moist food, than you should strongly consider switching to a dry food formula to help reduce the pungency of the stools.
In addition, sticking to ONE TYPE of food is very important. Switching from brand to brand can actually cause your pet's intestines to become highly irritated over time and many cats are predisposed to developing a condition called Inflammatory Bowel Disease which can often begin as just really smelly stools!
I would also recommend a diet that has white fish or meat within in it versus a diet with an assortment of dyes and flavorings. For instance, Meow Mix and Kit N Kaboodle are absolutely undesirable diets for cats to be on....they have way too many dyes, preservatives, and potential food allergens that your cat's intestines may react to over time.
My favorite diets are the Purina ProPlan Sensitive Stomach Salmon diet, Hill's Intestinal Diet I/D, Iams/Eukanuba Low Residue diet, and Royal Canin's Feline Rabbit and Peas diet are all excellent diets for cats with tendencies towards foul stools and GI irritation.
Besides diet, it is extremely important that you have your pet's feces analyzed by your vet to insure that your pet does not have type of intestinal parasite that could cause foul smelling stools. Commonly, cats can be infected with organisms called Coccidia, Giardia, and actual worms that must be treated with medications in order to eradicate them. In addition, bacterial overgrowth of the wrong types of bacteria in your pet's intestines can also cause flatulence and smelly stools.
I hope that you found this information helpful.
Please remember to PRESS ACCEPT so that I can be compensated for my time and professional recommendations concerning your pet. I encourage feedback and appreciate bonuses!!
Best wishes to you and your kitty,
Dr . Jodi Lynn Smith