WHITE BORDER COLLIES
Even more unusual than the red Border Collie is the white or mostly white individual. I don't know the AKC's attitude toward them; the British Kennel Club standard states: "A variety of colours is permissible, but white should never predominate." Breeders dislike them because the white puppy will often be the last to sell; I recently heard from a breeder who still has a white pup several months old, just because buyers don't want the white ones. In older days, it might be put to sleep right away.
The rationale against white dogs in sheep herding is that the sheep will not have sufficient respect for a dog that is the same color they are. (Marjorie Quarton, in All About the Working Border Collie
: "There is a popular idea that sheep . . . won't move for a white dog, having no fear of a dog of their own colour." This strange idea, like most prejudices, falls apart when you examine it. Most importantly, it assumes that sheep are always white. The flock I work most often is composed of black, brown, white, and parti-colored sheep. If we needed a dog that is a different color than the sheep, it would have to be pink! The sheep have no problem recognizing each other in all those colors; why should they have trouble recognizing a different-colored dog?
I have also heard it said that the white dog is OK for herding as long as it has a colored head; the sheep apparently look mostly at the head to determine the dog's color. But many great herding dogs have been black with an entirely white head! What are the sheep looking at in that case?
I once helped start an all-white Border Collie in herding; she had some problems based on early obedience training, but the sheep had no trouble knowing that she was a dog. I imagine that in the next few years, when more and more new handlers come into the sport of herding, that we will see more of these white dogs on trial fields. The new handlers don't know that white dogs aren't any good at herding; the dogs certainly don't know it, and the sheep apparently don't either.
What makes a white dog? There are a couple of possibilities. Almost all Border Collies have some white markings (I know of exceptions to this, too), arising as in all dog breeds from three or more different genetic combinations. As far as I can find out, the basic three are all alternate forms (alleles) of the same "white-spotting" gene, and they produce progressively more white on the dog.
The first results in either none, or very little spotting on the toes and chest. These Border Collies often descend from W. Hardisty's Jim, a black and tan dog with very little white; his dam was Merrie, a black and brown dog with little white, and his parental grandsire, Dickson's Ben, was mostly black.
The second produces a white blaze up the face, white on the feet, legs, belly and tail tip, and in a broad collar area around the neck. The pattern is variable, but the important element is that white doesn't occur outside these areas. This is the most commonly seen pattern among Border Collies. It is also seen in many other breeds of dog (collie, sheltie, Aussie, Boston terrier, St. Bernards, corgis, boxers, etc.) and even in other animals (rabbits and cats, especially). The pattern is often referred to as "Dutch," since it occurs in a breed of rabbits known as "Dutch."
There is then at least one allele (maybe two) which causes extreme white spotting, ranging from just a little more than the previous to an all-white body. Greyhounds and pointers also often carry this extreme white gene. This latter, often referred to as "white factor," is a recessive gene, requiring both members of a gene pair to produce the white dog. But it is not entirely recessive; a single white factor will cause variable amounts of white spotting on the dog's body. Usually small spots on the hip or back indicate white factor; some breeders believe that any white extended up the hind leg into the stifle suggests that white factor is present.
Many of the great herding dogs have been white-factored. Notable among them was Gilchrist's Spot; he had white travelling up the front of his hind leg clear to the hip. His grandmother was a white dog named Ann, who was also, through a different line, the great-great-grandmother of Wiston Cap.
The white head appears to be a separate genetic trait, although I don't see any studies of this. It is the typical pattern of the Old English Sheepdog. Many Border Collies have either a half-white or whole white face, usually blending into the broad white collar. Since white hair often grows longer than black, these white-headed dogs, especially if male, may look like they have a great white lion's mane. As far as I have seen, they make perfectly good working dogs. The rarest combination is the white-bodied dog with a white head as well.
There is one genetic form of white Border Collie, however, that is truly defective and should be avoided by both buyers and breeders. It is the result of breeding two merles together; it occurs in any breed (collie, sheltie, Aussie) in which merles are present. If a pup inherits the merle gene from both parents, he will be mostly white, with small merle spots. Especially if the white overlaps his eyes and ears, he may be both deaf and have defective eyesight. In a litter born to two merle parents, a quarter of the pups will be negatively affected. Since merle is an easily recognized color, this sort of breeding combination can be avoided; don't breed two merles together!
You should be very cautious about any mostly white dog on which the colored spots are merled, whether red or blue. Of course, the normal merle dog can also have the same white body markings as any other. Be sure you know the color of both parents (are they both merle? do they show signs of white factor?) and have the dog checked carefully for both sight and hearing.