Porcupines are peculiar animals. Along with beavers they are the largest rodents in the US. Beavers are busy and social. Porcupines move slowly and are shy. They don’t even interact with each other very much. They do get together in the fall for a short breeding season, and otherwise they travel alone. There is a riddle that asks, “How do porcupines make love?” The answer is “very carefully.” The truth is that during mating the quills flatten out so no one gets hurt.
The porcupines preferred habitat is high up in the top of mature hemlock trees, eating the tree buds and bark. They do climb down to vary their strictly vegetarian diet. They prefer to mind their own business, and interaction with other animals usually leaves the other party in pain. Whether a domestic or wild animal gets a nose full of those sharp quills depends more on the nature of the animal receiving the quills than on any aggression on the part of the porcupine.
My first 2 years out of vet school I worked in a general practice, treating both small and large animals. It would be a rare week that we weren’t pulling quills from somebody’s dog. Dogs see porcupines as intruders and try to bite them, sometimes repeatedly. I have always been amazed by dogs that don’t learn their lesson and bite more than once, or go on to attack other porcupines later. I owned a dog like that myself. She would tangle with both skunks and porcupines, and when she saw one would seem to say: “I’ll get him back for that last time!” In our vet hospital, unless the dog had just 3 or 4 quills we generally gave a short acting general anesthetic so that we could pull the quills with no distress to the dog. We used to count quills as we pulled them, and it wasn’t unusual to have well over 100, most in the tender nose and mouth. I don’t remember ever seeing a cat with quills. It’s just not in a cat’s nature to be investigating wild life as big as a mature 30 to 40 pound porcupine.
Horses also tend to shy away from porcupines who might wander into their pasture. However, in New England and Canada rural equine vets will get an occasional call. It’s not horse aggression toward the porcupine that causes the interaction; it’s the horse’s curiosity. If a horse’s nose comes too close the porcupine tail connects and the horse will jump back with some deeply imbedded quills. Usually there are less than a dozen, because horses, unlike dogs, would never consider a second helping. I have never had to pull quills from a horse more than once. Because there are so few quills, you may be able to pull them yourself without calling your vet.
You can pull quills with your fingers, but you have to grab them firmly and then pull straight out. They go in easy but come out surprisingly hard. I have found that needle nose pliers work best. The long thin jaws enable you to grab a few quills at a time. Back the horse into a corner and grab the quills firmly as close to the skin as possible. People always ask, “how hard should I pull?” You don’t have to worry about that. As soon as you close on the quills, just squeeze hard and hang on. The horse will do the pulling. Take your time, try to settle the horse and then grab a few more. Since horses don’t bite porcupines, it is rare to see any in a horse’s mouth. We will occasionally see quills in a lower leg, and I always assumed that perhaps that horse may have tried to kick the porcupine. When you have pulled all you can see, gently rub your hand over the nose as some may have penetrated deep and all you feel may just be the stub end. Fine forceps may be necessary for these.
Most of the length of the quill is yellow and feels soft because they are hollow. There is a belief that by snipping them short they will collapse and be easier to pull out. They do deflate, but what actually holds them tight in the skin are hundreds of microscopic barbs at the black tip. Each little barb acts like a fish hook. The black tip is very sharp and slides into the skin easily. It comes out hard because of the backward facing barbs. After the quills are pulled, there is often a drop or two of blood. When you find them, don’t delay trying to pull them out. As time goes on the quills tend to work in deeper. If a horse has many deep quills and is very swollen a dose of Banamine or Butazolidin may make him more comfortable after the quills have been pulled. Some horses will absolutely not let you near their face when they have quills. Then it’s time to call your vet who will heavily sedate your horse for the procedure.
We don’t see porcupines much in the winter in New England. Some authorities claim that they hibernate, and others say no, but in any event, they aren’t out and about much. You can spot them 40 or 50 feet up in the branches of tall pines and hemlocks, close to the trunk. In the spring and summer they venture out a bit and we start to see the evidence of their travels sticking out of our animals’ noses.
Dr. Jefferson is the founding veterinarian of Maine Equine Associates. He can be reached at www.MaineEquineAssociates.com His previous articles that have appeared in the The Horse’s Maine are archived on that site.