My Westie has had feces that looks like it is covered with a white sac. He is healthy but I am concerned that his poop looks so weird. Do you know what causes this??
Thanks

The truth is, I don't even try to remember things like that. I have a vet that knows and knows what to do about physical problems. I try to sort what is worth running to the vet, and what isn't. In this case, I think you should see the vet.

Could be a sign of worms... get him to the vet, fecal samples are fairly inexpensive to test, and, depending on your vet, you may know in a matter of 20 min what the problem is. Our dog had very loose stool, and I thought there might be something wrong... brought him to the vet, and lo and behold, he has hookworm. A $14 fecal sample test and a $9 tube of dewormer and he's good as new.
It's definitely worth checking out, esp. as some types of canine worms can be contagious to humans. And if you have kids, they're much more at risk than you.
Hope that helps!