Dewclaws are actually rudimentary thumbs and rear dewclaws are residual fixtures from the past. They have no function and are situated high on the inside of the leg above the foot. The do not make contact with the ground but are said to brush the dew from the grass and it is thought that this is where they get their name. They are called “Wolf-claws” in Europe but since the Wolf normally has no more or less toes than the dog it seems strange and unjustifiable to attribute the name back to the wolf.
Dewclaws may be Bilateral or Unilateral although most breeds seem to have bilateral front dewclaws. Rear dewclaws are not as common and are often removed from infant pups when they are present.
Sometimes there is only a vestige of the extra toe and it may be just in the skin or under it. Some Geneticists say dewclaws are Dominant and some say they are Recessive. This conflict does not alter the fact that the dewclaw represents a fifth toe, which is, through some evolutionary process no longer needed. There are some very good arguments for removing them from the rear legs as they can interfere with movement. Whether front or rear they can catch on things and even on each other and lock in a “handcuff” situation, causing a bad fall, fractures, and tearing of the skin surrounding the toe. Chihuahuas often injure their eyes with the front dewclaw when they use their front paws to clean their faces and eyes.
Because the mode of inheritance is still unclear and seems to behave differently in certain breeds it is accepted that dewclaws are Dominant Recessive with Incomplete Penetrance. They are definitely autosomal which means they can be passed on to either sex.
More confusing yet interesting facts are that, double dewclaws are recessive to single ones, dogs can carry both genes and that those genes can act independently of each other. This means that we can see parents without dewclaws produce pups with 1 or 2 or 1 double and 1 single or none at all.
Although they are usually removed within a few days of birth if the breeding records show that two pups were born with rear dewclaws, when mated together the pair may never produce them or may produce any of the combinations demonstrated above.
DOCKING TAILS AND REMOVAL OF DEWCLAWS
You have to gather the equipment you will need to perform the procedures. This consists of, among other things, a tool called a Ferguson Angiotribe. I know there are other ways to do tails, but this is the coolest. It is sort of like a pair of forceps, but the Ferguson Angiotribe has a tongue and groove arrangement on the business end. I think it is really a vascular clamp, but it does a really good job on tails.
You’ll also need a small pair of scissors, manicure size, but not with those dopey round things on the ends of the blades, like the scissors you had in kindergarten. You need some that look just like regular scissors, but small. Alcohol to clean the tools, some dental floss, styptic powder, an antibiotic powder and some small adhesive bandages and you’re good to go.
It’s a good idea to have an assistant to help hold the puppies still while the tails and dewclaws are getting done. The puppies are a little wiggly and it makes it easier if someone helps.
First clamp the Ferguson Angiotribe on the tail, twist the part of the tail that was protruding from the clamp and pull it off, and then move to the dewclaws while the clamp was still attached to the tail.
The trick to holding the puppy when it came time for the dewclaws to be removed was to put a finger behind the elbow of the leg that was being worked on so the puppy couldn’t pull its leg back. Then, once the dewclaws were snipped off, the Ferguson Angiotribe was loosened. The clamp usually had supplied enough pressure to the tail while the dewclaws were being done that the tail didn’t even bleed so it was a fairly neat procedure.