Coat Colours In The Lucas Terrier

I do not intend to go into the colour inheritance of the Lucas terrier in any great depth. I believe that if breeders have a grasp of whether they are likely to produce a litter of coloured puppies, a litter of white-bodied puppies or a mixture of both then that is probably sufficient. If there is a desire to learn more about canine genetics then there are many books available which study the subject in great detail. Tan, saddle and tan, white with tan, white with black or white with black and tan are all colour variations that are acceptable within the Breed Standard. The only colour variation that occasionally crops up, I have known of only two in the UK, which is deemed to be undesirable is completely, or predominantly, black.

I believe the whole colour in the Lucas comes from the Agouti gene. The alleles within this gene are as follows:-

As - Dominant black

AY - Dominant yellow

A - Agouti

asa - Saddle marking (black saddle with extensive tan on the rest of the body)

at - Bicoloured (coloured with tan points, for example, the Rottweiler)

a - Non agouti

Red/tan Lucas terriers are born with an overlay of black hair - this can also be seen on the tan patching on a white-bodied dog - which disappears in the adult coat. If Lucas terriers did not have this sabling in the puppy coat then it would be possible that some inherited their coat colour from the E gene in the form e which gives clear red or tan. I have never seen a Lucas terrier without sabling in the puppy coat so am certain that none of them are tan due to the recessive allele e.

The saddle marking allele is recessive to sable and this explains why saddle marked puppies turn up in litter from tan parents. My opinion regarding some people's dislike of saddle marked Lucas terriers is that they are not going to go away and it seems rather shortsighted to exclude them from the breeding programme purely on the basis of colour - if only there were enough top notch Lucas terriers around to make this possible! We must try to see beyond the argument that they should not be bred from because Sir Jocelyn Lucas didn't like them. Sir Jocelyn Lucas lived in another age when large kennels of dogs were not uncommon and breeders could afford to be picky about little things like colour. Few dog breeders nowadays are in such a fortunate position and certainly Lucas terrier breeders are not.

When a Norfolk and Sealyham are bred together a gene from each parent is inherited and in terms of colour this means, simply, that the dominant colour of the Norfolk will mask the recessive white of the Sealyham but there is incomplete penetrance of colour and the fact that the dog carries white is evident. Thus, there will be some white areas on the dog's coat. The genetic term for these white markings found on the hybrid is Irish spotting, and this refers to white areas on the extremities of a coloured dog - the extremities basically are nose, toes, tummy, bib, on or around the neck and the tip of the tail (if the tail is docked this will most likely be removed).

When Norfolk/Sealyham hybrids are bred together the probability of finding white bodied puppies in the litter is high - Lucas litters are small, so all the possible outcomes may not be seen in the one litter. There can be three genetic outcomes when two hybrids are bred together - coloured puppies with no white markings which indicates they do not carry the white gene, coloured puppies showing evidence that they do carry the white gene as they are Irish spotted, and white-bodied puppies with coloured areas. The white-bodied puppies are, as the name implies, white with coloured markings as opposed to Irish spotted, which are coloured with white markings. These white-bodied puppies are described as piebald spotted, they have a white base coat and large coloured patches on the head and body. When white-bodied Lucas terriers are bred together all their progeny will be white-bodied and very often have less coloured markings than their parents. These are what is known as extreme white piebalds - this means that they are predominantly white and the coloured patches may be confined to eye patches, coloured ears and, on occasion, some small body spots and/or a tail spot. It is recommended that extreme white piebalds are mated to dogs not carrying white, are Irish spotted or piebald spotted. Continued matings between extreme white piebald terriers are not recommended. It is believed that there may be a correlation between deafness and an absence of head patching (research done primarily with Dalmatians), therefore, it is important that Lucas terriers should retain some colour on their bodies, and, particularly, on the head.

There is a proposed gene (Little, 1957) called the paling gene, and, if it exists, in it's recessive form, p, it reduces black and brown pigment. Willis, 1989, discusses a paling series in which two alleles, INT and intm causes dilution or paling of colour and the recessive, int, does not. If this paling gene exists then the Lucas terrier has it!! Saddle and tan Lucas terriers are born coal black and rich red tan but in the adult coat the black pales to blueish gray and the red tan becomes fawn. Tan Lucas terriers lighten up a few shades from the dark tan of the puppy coat to become a pale wheaten colour and the same comments regarding paling can be applied to the black and/or tan markings on predominantly white terriers.

Click arrow to return to index page