Welcome to JustAnswer! I am a licensed veterinarian and would be glad to help!
Unfortunately - the answer is yes.
From experience - cats can be quite fickle with their food intake and there is a very good chance they may develop of a food aversion with a change such as this.
This is normal for them in the environment - it is called copraphagia: LINK
What then happens - they eat the stool laced with something that tastes bad, they then associate the stool with a bad taste, then in the future understand and associate the taste and stool - then stop eating and going after the stools
There is also a product on the market called Forbid (LINK HERE) - more for dogs that eat their own stool rather than dogs that eat other's stools.
Forbid would be an option for you.
Otherwise I would not use chemicals.
Moreover, anything you add to the diet, tasty enough for them to eat...is only going to entice the dogs more, not deter them
I Would certainly consider training them, listed above - as with many causes in dogs - they respond to training well!
My personal dog responded best to training with bitter apple for issues such as this.
You are very welcome!
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