© Marco de Kloet

A gentle greeting or play behavior with one dog doing a muzzle grab to another dog.

In her book “Inside of a Dog”, Alexandra Horowitz discusses how dogs respond to raincoats, muzzles, and other items they are asked to wear by humans.  She says “There are occasions when wolves get pressed upon the back or head: it is when they are being dominated by another wolf, or scolded by an older wolf or relative.  Dominants often pin subordinates down by the snout.  This is called muzzle biting, and accounts, perhaps for why muzzled dogs sometimes seem preternatually subdued.”

Notice in all the photos of canids muzzle grabbing or muzzle biting each other, how little apparent struggling appears to be offered by the dog whose muzzle is held.  They do indeed seem subdued by the muzzle bite.