Labs- numerous times, I volunteer at a humane society and they are the worst.
Skye Terrier- the little runt that runs around our neighborhood all day and never is in its own yard.
Yorkshire Terrier- many a nip to the hand.
German Shepherd- required stitches, he jumped his fence.
Doxie- they have strong teeth
Feral cats- I've had my share of these. Make up the most animals bites reported, also the worst because of bacterial infection.