A porcupine quill has tiny barbs that work the quill deeper into the flesh. Fast removal is essential so that the quills won’t become more deeply imbedded. If there are only a few quills, extract them with needle-nose pliers.
First muzzle a dog by closing its mouth and tying the jaws. With the pliers, grasp the quill near the skin and pull straight; don’t bend or twist the quill. Treat the wounded areas with an antibiotic recommended by your veterinarian. Observe the wounds for a week to see that they heal well.
If a quill breaks, move on to the next one quickly: take the animal to a veterinarian as soon as possible to have any broken quills surgically removed. If there are many quills or they are embedded under the surface, a veterinarian should extract them under anesthesia. If you keep pets in porcupine country, keep them in at night.