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| These images were provided to me by a reader, Susie, and are copyright to her. |
These five puppies are all from the same litter, and are from a line of working beagles. I was not given any names. For this post I have given them numbers, from left to right in the above picture. This litter is a very good example of how much variation can be seen in siblings, especially in breeds that express the piebald gene.
Puppy number one is, of the litter, the most like what most people would call a "classic beagle." The coloration is saddled tan with minimal piebald white. It is the color that seems to most often be seen in show beagles. The most likely genotype for this puppy is asas CC Dd sisp tt Uu. Puppy number two is, in contrast, quite different in appearance from what would be expected from people who have never seen a working beagle. This puppy appears to be blue sable with minimal piebald white, moderate ticking, and urajiro. The most likely genotype for this puppy is Ayas Ccch dd sisp Tt uu. Puppy number three is also quite interestingly colored. This coloration appears to be blue sable with minimal piebald white and urajiro. The most likely genotype for this coloration is Ayas Ccch dd sisp tt uu. Puppy number four is piebald sable with heavy ticking and urajiro. The most likely genotype for this pup is Ayas CC Dd spsp TT uu. Puppy number five is rather similar to puppy one in appearance, but is also quite different. This puppy's coloration is piebald saddled tan with heavy ticking and urajiro. The most likely genotype for this is asas CC DD spsp TT uu.
Now, you may be wondering how I came across some of these decisions. Saddle versus sable is fairly easy to pick out, mostly coming from the density of the black hairs across the back. Saddled dogs, especially those with shorter hair like beagles, will have a consistently dark saddle (unless the undercoat is prominent). Sables, in contrast, will look more like they've been sprinkled with pepper, even when the sable becomes rather dense. The intensity of red is also rather clearly defined, with all of the dogs being fairly to quite dark. As for the blue coloration, I almost missed it. However, when looking at the puppies next to each other, some of them do appear to have a gray cast to the black in their coat. The puppies are all piebald of some sort, but I am assuming the ones with more color have a copy of the Irish white gene since they are very close to Irish white in their amount of white. Ticking is obvious: some puppies have spots and others don't and it stands to reason that the ones with moderate ticking are heterozygotes. The urajiro is quite clear, especially when comparing puppy one to its siblings. That pattern of paleness to the face is really only seen in very old dogs and dogs with urajiro-type markings. Since they are puppies, they must have urajiro. As for the other carries, mostly it's arbitrary guessing.
As for what the parents look like, that is a very good question. From what can be seen in the puppies, a few things can be assumed with a fair likelihood of being true. One parent is most likely sable, the other saddle, and the sable parent must carry saddle (asas, Ayas). Also, one parent was probably moderate piebald and the other piebald (sisp, spsp). Both were most likely moderately ticked (Tt). One likely had urajiro, while the other does not, but is a carrier (uu, Uu). As for blue, I suspect both parents were carriers (Dd). Last but not least, one parent was probably intensely red, while the other was only moderately intense (CC, Ccch).
Pretty amazing you are able to determine so much detailed info from the photo. Had to google "piebald gene" ...does this also apply to white "tufts" of fur/hair or just the larger patches as well? Interesting stuff.
ReplyDeleteI did use some more photos, including the ones linked in the explanation.
ReplyDeleteAs for what piebald means, it can mean a variety of things. Piebald is a dog that tends to be around half white and half non-white, but can vary a good deal in either direction. It is also sometimes called pied, parti-colored, parti, and a few others. The terms tend to vary by breed. It doesn't apply to patches on the body, but in fact to the overall amount of white on the dog. Some piebalds don't look very different from Irish marked dogs, Irish markings being what is seen in most border collies. However, as a general rule of thumb, a dog crosses the line into piebald territory when the white is extensive enough to cross the topline (the area between the shoulders and base of the tail). When the dogs is nearly all white, this heads into extreme white territory, which is in fact controlled by another variation of the white spotting gene. All told, the white spotting gene has four variations: solid (S), Irish (si), piebald (sp), and extreme white (sw). Combining two of the genes into different combinations produces a variety of results.
Here's some other piebald dogs I found that cover the piebald spectrum from minimal to heavy, if it helps. It's quite possible that the minimal dogs have one copy of the Irish gene and one copy of the piebald gene, and that the heavy dogs have one copy of the piebald gene and one copy of the extreme white gene.
minimal
minimal
minimal-moderate
minimal-moderate
moderate
moderate
moderate-heavy
moderate-heavy
heavy
heavy
And then there's extreme white