Fortunately, scars shouldn't affect a lamb's placing in the ring. The biggest concern with dog bites is infection. Work closely with your vet to keep the lambs on an aggressive antibiotic regime until the wounds begin healing. Beyond that, I like Corona ointment a lot. Seems to hasten skin healing and speed hair regrowth. I wouldn't use it one large, gaping wounds, but once they start closing up and healing, it may be useful.