Man that is nasty. hope everything heals up well!
BTW: did the emerg insist on a physical exam and blood tests so the dog would not get sick?
From the net:
Species 8472's own somatic cells can become extremely virulent when in a foreign blood-stream, duplicating themselves rapidly. When Species 8472 wounds a victim, some of the former's cells are left in the wound. These stray cells multiply, spreading through the victim's entire body, consuming it from the inside out while the victim remains conscious.
Looks like you play with dogs like I do! rough and tumble with a lot of laughing and growling (me not the dog)
If the dog starts ordering crossbows and target shooting Call the vet!