Sounds like Momma Fox was out with babies teaching them how to hunt. As with any young ones, they were excited by the chase, not so much as the food. Skin closes in post mortum appearing like pin holes= pups teeth.
Its such a shame, keep your goats in at night.
We had a farm local here in Maine, when a pals sheep (pregnant) were killed by a husky that was someones favorite pet. The sheep ran and the chase was on. Unfortunately the dog was excited, played them to death, nipping and biting them. Its a shame when its your pet or food source.