Lethal White in Shelties?
I am a professional horseman and I've been painfully aware of the negative effect extreme amounts of white can have on the health of our paint horses. Lethal White Syndrome is a well documented problem that occurs in horses who get a heavy dose of the Frame Overo gene. A broodmare of mine once had one of these 'lethal white' babies, it never pooped and it only had one ear (literally). Heavy doses of 'white factor' are deadly in horses, could the same be true in dogs, shelties even?
Nearly all breeders and most lovers of breeds that have the merle gene, know not to breed to merles together. A double merle puppy/dog (with 2 copies of the merle gene) often has serious issues with blindness and deafness. Could they also have internal issues as well? I have been told by owners of cool looking dachshunds that when there merle gene is doubled it produces some awful effects on the inside of the body. Not considering merles, could white factor itself become too highly expressed to be safe?
I raise beautiful tiny shelties intended to be long-lived companions for their families. Healthy genetics are my top priority. I have noticed an unusual trend that I believe has been swept under the rug. I believe if it were studied and understood, it could save not only breeders but also families much heartache and expense.
My clients are wonderful! They desire tiny shelties with which they can spend their lives. They love a beautiful exterior but their first priority is a healthy, long-lived, family member too. I understand basic genetics and when my clients were desiring sable puppies with blazes and full white collars, I intended to better my odds of producing what they desired. I observed that the majority of shelties fitting this description were 'white factored'. I made a concious decision to aquire white factored dogs for my breeding program. 'Unfortunately' (or even though I didn't realize it, fortunately) many of the dogs I found who fulfilled my other requirements (size, temperament, personality, health, age, etc) were not white factored. Even my best foundation breeding female, Cassie, had very little white. I ended up with a lovely group who was about half white factored and half non-white factored. How could I ever comprehend that this was a wonderful accident?
I did a good bit of study on sheltie color genetics in an effort to produce puppies who would always be desirable. As a responsible breeder, my intention is never to flood the world with more unwanted dogs that will be abandoned and abused. My intention is to produce superior quality dogs that will always be desired. In the midst of all the spay/nueter push, someone needs to make a concious decision to build a better pet so that when the indiscriminant breeding is stopped, there are great dogs from which to choose. I understand color and markings are a big part of what draws a person to a dog.
I found the 'Irish' markings to be solidly established within the breed; white chest, white socks and white tail tip. Few shelties do not possess at least these white markings. These markings appear to hold nothing negative at all. These are completely 'healthy' markings.
The facial markings appear to have their own gene separate from white-factor/non-white factor and the Irish markings. Face markings like blazes, stars, snips and stripes seem to have no impact on the health of the dog.
White factor seems to have a greater impact than ever documented. A white factored dog is fairly easy to spot, high white legs and large white collar. The classic sign is white extending up the stifle or even over the hock on hind legs. Lots of tail white (more than a tiny tip) and body spots are indicative of a heavily white factored dog. These are the classic signs, look at the whole dog, you could be fooled.
There are white factored dogs with thin or broken collars, just like there are non-white factored dogs with full, thick white collars (like my Bullet). Short socks on the hind feet are a great indicator of no white factor. These thick collared dogs with short socks are very valuable in a breeding program because they bring 'good' markings without risk.
The traditional square tells us; If one breeds 2 white factored dogs (one white factor gene, one non-white factor gene) if you get 4 puppies, you will get 2 white factor puppies, one non-white factor, one color-headed-white puppy. This was discouraged because the traditional Sheltie Standard only allowed up to 50% white and this cross was likely to produce 3 puppies that would not stay under 50%. I used to be curious about why the show breeders didn't attempt to get those classic 'Lassie' markings (blaze, full collar, high white legs)? Now I understand why I believe the standard was created! I also 'get' why that same reason was not disclosed or talked about. How very interesting.......
Although I have found NO DOCUMENTATION to prove my experience, I am putting these ideas out to hopefully help other breeders and more so to help buyers become aware of the possible 'fading' of that beautiful puppy they picked out at birth.
I have produced many healthy white-factored puppies. All our color-headed-white puppies have been healthy. I have noticed in several litters where I've crossed 2 heavily white factored dogs (with high white legs, huge collars and slight body spotting) hoping to get 'loud', unique markings, I have had many more health problems and death prior to 3 weeks of age. These deaths involved digestive tract problems and were nearly impossible to stop even with 24 hour intensive care.
What have I noticed? I have noticed the most heavily white factored puppies in a litter tend to be the smallest. Not always, this is no scientific study, just 1 breeder paying attention. When I have had actual 'runts' (who displayed 'runt characteristics'
) they have been nearly always heavily white factored. No matter how hard I tried, those have all passed within 5 days of birth, some never pooping. Which is classic 'lethal white syndrome' in horses....
I have a horse who is the product of 2 'heavily white factored' (not identified like that in horses but I can see the similarities) parents. She nearly died many times from extreme colic symptoms especially when she was young (under 3 yrs). She appeared to not absorb the nutrients and calories in the feed like other babies/horses. She appeared at least 1 year behind her peers in growth and development. Her face was/is oddly slightly longer and thinner than either parent. We have given her the best and most aggressive care and she is currently 12 years old, but still 'colics' more easily and more often than our other horses.
Her mother had 'heavy white factor' and had nearly as much trouble with frequent colics. Sadly her mother died from a nighttime colic that was not caught in time.
I had another unrelated gelding with this same type of color pattern. He also had odd colics. We have no other good word to describe a digestive tract issue that causes pain and compromise (sometimes including death).
Although these three horses were obviously not lethal whites (they were alive as adults), they certainly had something not right. I have coined it 'Incomplete Lethal White' and I feel the intestines either developed more slowly or are just not as big, strong, resilient as the 'normal' horse.
Do you also see the similarity between the color pattern on these horses and these puppies? I find it facinating.....
We did raise a gorgeous, beautiful, swirly girl out of Julie a couple years ago. Not sure the difference, but the white on her head/face, and legs were not as extreme as these puppies that passed. Seems like a certain percentage of dark color is needed to insure good health on the inside of the body.
I loved this little female and wanted one like her but I have not been able to reproduce the excessive swirling on the back with the short sock and normal blaze. I think those 2 things were what helped her do so well.
I notice the huge blazes and/or the huge white collars are the puppies I struggle with the most (after wild 'mismarks'). These are also the highest in popularity. I also notice other breeding programs have had similiar experiences. I have a friend from whom I bought several beautiful dogs I hoped to use for breeding. She had had a terrible previous year losing nearly all of her puppies. Now I notice she (as I had tried to do) had collected a group of nearly all beautiful white factored dogs. She had bred them and the ones who had delivered puppies had lost the majority of those puppies for no apparent reason. She had gotten really frustrated. I think heavy white factor was to blame.
I had a beautiful CHW female that would not carry a litter to term. Three litters were delivered 3 weeks early and dead. One litter was born premature but had one tiny female that was alive. She had a large blaze, large collar, high stockings and died at 3 days despite our best efforts to save her. Mom was healthy but would not produce.
I have 2 full sisters/littermates. One is substantially larger (heavy white factor) and one is TINY (non white factor). They were in a litter of 5, they were the only survivors at 8 weeks. The middle puppies (I don't know the colors) all 'faded' and passed. Odd.... I bred one of the girls (heavily white factored). I meant to breed her to my white factored sable male but a mistake by a helper bred her to Bullet (no white factor). Thank goodness bc all but one of her puppies were freakishly tiny at birth. The big one is of course thriving and is well marked but not white factored. At about 1 week the puppy with the most white stopped nursing and Ive really struggled to keep him going. Now the next most white factored puppy is also providing a challenge. I find the coincidence interesting.
I also recently delivered a litter prematurely out of our extreme white factor female, Jamaica, and out of my white factor male, Hansel. All were heavily white factored, all passed before a week old despite 24 hour care.
Last year I struggled with a heavily white factored male in a litter of 5 puppies, the others were not nearly as white, he barely survived with many experienced hands helping in his care.
Julie's last litter had some heavy white factor puppies and had a couple with little white. We lost 2 of the litter, the 2 with the most white, the second at 2 weeks old when he spontaneously started loosing water in his poop. I rushed immediately to the vet and nursed for 3 days tube feeding and sub-cutaneous fluids every 2 hours but still lost him. Vet had no explanation, the remaining 3 puppies were unaffected. The next most white male had a slight, 'incidental' heart murmur. The least white puppy (no collar) is about twice the size of the other 2. Facinating.....
Lastly I notice my tiniest shelties, Coco and Lyric, are freakishly small, totally healthy and not white factored!
At this point I have decided to make some changes to my breeding program. I will not breed two white factored dogs together. We will produce more puppies without big blazes and big collars, but I feel it will be an excellent choice to insure the healthiest litters possible. Healthy puppies with chrome are a bonus, but puppies must be healthy first!
Here are a couple good links to color genetics articles. They do not imply that white factor is a problem, but they do have lots of great information: