Rough Collies and Smooth Collies have identical standards with the exception of the coat, but interestingly, both varieties can be born in the same litter. As we’re about to wade into the tall grass again, this can only mean one thing: We’re about to talk about the “G” word (genetics), so we’re counting on genetic wonks to help us out if we get in over our heads.
In Collies, the smooth coat is the dominant gene. For a dog to be Smooth, it has to carry the dominant smooth gene.
If a Collie is a rough, however, it doesn’t carry the gene for the smooth coat; Since there’s no such thing as a recessive smooth gene, the only way for to get a Smooth Collie from a Rough Collie is to breed it to a Smooth, and that’s how Rough and Smooth Collie puppies can be born in the same litter.
Roughs cannot produce a Smooth, but the Smooths can produce Roughs since Rough is carried as a recessive gene.
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We have a smooth produced by a rough dam.
Easy. All they need is one smooth parent
I do too. Am trying to understand how this can happen. Both parents are rough. Mother collie; father Australian Shepherd.
How can this happen?
could be a false smooth. there are actually several different types of longhair genes, and aussies in particular can be longhair but look relatively smooth. look for any feathering (long wispy looking hairs on the legs, butt, tail, around the ears or cheeks). if your dog has any feathering at all, it’s longhair by genetics. there are also cases where genetics are “incomplete” such as with white patterns.
genetically any dog who is SS for white, should be solid colored. However there are plenty of cases in rough collies where they are genetically SS solid colored, but have physical white patterns like an irish white (sisi). genetics can be tricky and don’t always play by the rules lol
Rough is recessive; ANY rough parent can only give a rough gene to the offspring. But smooth is dominant. Since each pup gets 1 gene from each parent, if a pup has a rough gene & a smooth gene, it will have a smooth coat. If it has 2 smooth genes, it will be smooth, and it will be rough ONLY if it has two rough genes. You can tell by looking that a rough that a rough dog has 2 rough genes. But without breeding it or doing a genetic test you can ‘t know what the smooth dog has, since it only takes one smooth gene to get the smooth coat. The dominant gene suppresses the recessive gene, so a smooth collie can have 2 smooth genes or one smooth & one rough gene. The only breeding guaranteed to produce ONLY rough coats is rough to rough. Any other combination can produce both coats, depending on the genetic makeup of both parents.
Each pup gets one gene from each paremt.
Since rough is recessive, and smooth is dominant, in order to get a Rough coat, your smooth has to have one dominant Smooth gene, (to even be smooth) and one recessive rough gene to pass on to the rough pups that are produced. They got one gene from the rough coat parent, and will be rough or smooth depending on which gene they get from the smooth. If the smooth has two Dominant smooth genes, no matter who they are bred with, they will always have smooth coats, they have no other gene to offer. Of note- every litter is a roll of the dice. There is no way to predict the percentage. And sometimes they all end up “Sr”, so one would think the smooth was SS, but actually all the puppies are Sr too.