[Altariel]

Had you read the material at the link, you would see that they do—and that dog owners may miss an animal’s signs of pain.

A few more resources for you:

http://www.southplattesentinel.com/2012/12/dogs-hide-pain/

“Dogs and cats, like human beings, are great actors. Act One usually involves masking the outward signs of pain – but they do it for vastly different reasons. Veterinary clinics and animal hospital teams know from experience that cats, as solitary creatures hide any sign of weakness could make them prey to other stronger animals. Therefore cats will always be masters at concealing any pain. Dogs hide pain too, but they are different.”

http://unionvet.ca/2013/09/30/how-to-tell-if-your-dog-is-in-pain-act-one/

http://www.mypetsdentist.com/pain-related-concerns.pml

[miss marmelstein]

Don't bother. I've owned dogs for 40 years, I'm an ASPCA volunteer and I refuse to treat Labrador Retrievers like Dresden shepherdesses. That's ridiculous. I used to use my Black Lab as a foot stool. I would rest my feet on him while reading.