Porcupines, "porkies" or "quill pigs" cannot throw their quills at you or your pets. You must actually touch the quill even very slightly for it to stick in you. If you leave porcupines alone they will continue on their way and leave you alone. However, most of our pets have not learned that lesson and they can be seriously or very painfully injured from encounters with porcupines. Cattle and horses have also been known to nuzzle a "porkie" and get "quilled." Quills left in pets or livestock may cause fatal injury if not removed promptly.