So if you have owned an aussie for any amount of time, I'm sure you've heard the term "mismark" referring to an aussie. Maybe your aussie, but what does it mean? Is it bad? Does it mean it's unhealthy? How do you know if your aussie is a mismark?
What is a mismark?
A mismark is a simply a dog that has markings that are outside the desired boundaries. The sketch included with this post shows a "Max White" aussie- one that has the most possible white without being a mismark. Notice the dog still has color over the eyes, ears, and saddle area. When white is found in any of the places that this photo shows with color, then the dog is considered a mismark. The white between the eyes (called a "blaze") the noseband, the collar area, and the white legs are the result of the Irish Spotting gene and are very common in our breed. When white is outside these boundaries it is usually from the piebald spotting gene which is linked with health issues, mainly blindness and deafness.
Can color really impact health?
"White is probably the most problematic color (actually lack of pigment) in our breed. It is not the white coat itself that is unhealthy. White outside of the areas prescribed in the standard is a warning flag that there may be health problems related to lack of pigment or to homozygousity of the merle gene. White or excessively white Aussies can be produced by several mechanisms working singly or in combination. Among the defects commonly associated with excessive whiteness are deafness (full or partial in one or both ears) and vision problems and eye defects from mild to severe. There are several causes for whiteness, but the two most common are recessive pattern whites and the mating of two merles to produce a homozyous merle." http://color.ashgi.org/color/white_aussies.htm
My aussie has a white ear/eye, is he going to go deaf or blind?
Probably not. Most mismarks happen as the result of normal, responsible breeding. However, those from mismarked parents are more likely to have issues than those from correctly marked parents. The deafness and blindness is not a progressive issue. If the puppy is going to have any issues, they will be present at the time your puppy is picked up. (However, puppies are smart! Many people can't tell if a puppy is deaf because they are so sensitive to floor vibrations, their siblings, etc.) If you have any concerns, a veterinary ophthalmologist (eye specialist) or audiologist (hearing specialist) will be who you should contact. A normal vet cannot perform the CERF (eye test) and BAER (hearing) tests needed to confirm one of these issues.
My aussie is a "mismark" but I was planning to breed him/her. Can I?
You shouldn't. Responsible breeders would have pointed this out to you before you purchased your dog as breed potential. If they didn't, it is up to you to choose to better the breed and NOT breed your mismark. Mismarks are showing the piebald spotting gene which can cause deafness and blindness in them and/or their puppies. When bred, the mate could be a silent carrier of the gene multiplying it in the puppies. We are responsible for the puppies we produce, and intentionally breeding a dog that could produce deaf and blind puppies is an injustice to the puppies produced. It's inhumane. Please don't breed mismarked Aussies!
Chances are good that your mismarked baby is completely healthy! Honestly, I think they are some of the absolute cutest babies out there! They happen in all programs, responsible and not, but it is our responsibility to do our best to produce healthy babies- not ones at an increased risk for serious defects that can easily be avoided. The breed standard was created for a reason- to keep our breed healthy and functioning as it should, not for vanity. Beauty is in the eye of the beholder, but HEALTH is a responsibility.
-- Amanda Leland
Renegade Mini Aussies