They have supplements at the pet stores you can give the dogs that do this. I saw some at Petco.....
Our dogs prefered cat poop over their own food. The bad part of them eating it was that they would throw it up after, and there was cat litter in it, which I'm sure is not good. We took a wooden baby gate that is expandable, and cut off two or three of the bottom bars. We attached one end permanently to the door way of the room with the litter boxes, and the other end had a hook and eye closure for easy opening and closing. The bars removed on the bottom gave the cats enough room to crawl through but not the dogs.
lol it is quiet funny but just nasty!!!.... im like "whats wrong with you!!... your eating your sister poop!!!".....hahahaah i will try the meat tenderizer.... glad to hear im not the only one with a poop eating dog!!... hahaahahahaha thanks again!
LOL! I'm sorry, but I have to laugh. I have a dog with the same issue concerning cat poop. I really have to watch her on walks. If there's a cat mess within 20 feet and I'm not watching her body language, I end up being dragged by the leash until she gulps it down in one swift bite. GAG!
The condition is called pica, and while it's a revolting practice it's generally harmless. There isn't a clear reason why dogs (and other animals) eat feces, dirt or other non-food items. The one explanation regarding cat feces being attractive to dogs that makes some kind of sense to me is that cat food is higher in protein than dog food. Enough of that protein makes it through the cat into the feces to make it highly attractive to dogs.
Another angle to look at is nutrition. One theory is that a dog with pica may be trying to make up for nutritional deficiencies. Maybe try a multivitamin for a few weeks and wait and see if that stops the behavior.
Since your dog with pica is now eating the feces of your other dog, you might try sprinkling a little meat tenderizer in the non-pica dog's food. I've read that the meat tenderizer can make the feces less attractive.
I suspect the only thing you can do about the lure of the cat poo is to keep the litter boxes out of the dog's reach. My sister has this problem with her cat and dog, and ended up using a baby gate to block the dog's access to the litter box. The cat easily jumps over the gate to get to the box.
Pica is a common problem with no clear solution. I'm certain more people will post with ideas for you to try. That's about all you can do - keep trying different things and hope you'll hit on something to shut off the poo appetite. I think some dogs simply like the taste. :-O