A friend of mine had a dog that started eating a thread and COULDN'T stop until the thread came to an end. The dog had to be operated on before it entered his intestines
and the dog almost died!

My Cattle Dog did this a few times when he was unable to evacuate because his anal glands were full & making him constipated. They mistake the string/threads for grass.

If that's not the problem, try some Sour Apple spray on the rugs. I believe it's fabric safe & doesn't smell to humans, just tastes horrible to dogs.

that but he will chew on socks, t-shirts, anything soft he can get his mouth on! I'm concerned about intestinal blockage
and have taken him to the vet but the vet just gave him kaopectate (for dogs) and an antibiotic. His stool is always very soft to runny and the vet says "change his food"! I have tried about 5 different kinds of food (even the expensive ones you can only buy from the vet!) and he'll only eat one brand. I guess I'll have to change vets! Maybe I'll ask them to see if his anal glands are full!
Thanks for all the suggestions - I knew there were animal lovers on this blog.

... And he's eating things that could be construed as "fiber", you may want to give him Activia or some other plain yogurt with his food (a couple tablespoons per meal) as a pro-biotic. His internal balance seems off, one way or another. I had a foster dog who pooped seemingly half his weight's worth every day & the vet recommended the yogurt. It dd help.

Let us know how it goes!

problem continues. He goes back to the vet in about a week if things don't get better! He is my baby (wish I new how to post pics, I would). Otherwise, he seems full of vim and vigor. He has been on a chicken and rice diet for 5 days now (yes, I cook for my dog but not so much for my husband!), he plays and runs/jumps and is very lively. His appetite is good and he is urinating frequently throughout the day. I appreciate all the comments (well, most of them) and help from this forum. Thanks again.