The Australian Labradoodle has one known genetic issue cropping up commonly around the globe. Many breeders have yet to be able to stop it because it involves eight genes. Any two of the eight genes randomly matching can cause it. Approximate 75% of Australian Labradoodles, and on occasion Labradoodles and Poodles, seem to be carriers of one of the eight, so which random breeding partners express it in a few of their offspring is always a surprise.

What is this issue, the slight typically juvenile under-bite? The under-bite is far from a serious concern compared to Hip Dysplasia, Addison's, eye issues such as PRA, cardiac issues, and all those at a life-altering level. However, it does happen, and although commonly outgrown by adulthood, it is visible.

It is homozygous recessive, therefore both the dam and the sire are just as "guilty" of passing on the defect in the offspring. What is the chance of it showing up in future breedings, if both dogs are carriers? Well it is more complicated than that because it represents eight genes and the dam and sire would have to have the random match of some of these eight but if we assume neither express the gene but are carriers of one of the eight or a perfect match, then, if you breed the two, your mathematical probabilities would be 25% of the pups would have under-bites, 25% would be normal/non-carriers and the other 50% would be carriers but without under-bites. If you bred a carrier to a to a sire or dam with an under-bite the math works out to be 50% with under-bites and 50% as normal but carriers. Now, again this is assuming the trait is homozygous recessive as science indicates and the above percentages are just the probabilities.

ALAA member breeders are aware of this issue and pedigrees commonly expressing the trait. We are trying to breed away from it. This may be a long road since the under-bite is as stated a genetic issue of eight genes requiring just one to be passed by both the mother and the father and because it is nested in so many pedigrees.

A slight under-bite in a puppy is one of the traits making an Australian Labradoodle a pet quality puppy.  It is commonly not possible to actually see the under-bite until teeth come in around 6 to 7 weeks of age. These are slight under-bites, and are typically gone by the time the adult teeth arrive, especially if the breeder takes extra measures. If you are concerned about under-bites or your puppy is arriving with a slight under-bite, and you are concerned, please have your vet discuss the issue with you  to ease your mind. There are a few purebreds in which the under-bite is the breed standard and these breeds have no known issues throughout life due to this bite, these include boxers, bulldogs and Shih-Tzus, and Lhasa Apsos.

What is being done?

Typically breeders have their vets look at the jaw and teeth. At this point they are looking at the puppy teeth that have grown in from age six weeks to four months. At approximately four months the puppy teeth fall out and the adult teeth arrive. If the vet determines a positive approach is to remove some of the puppy teeth between the canines, most commonly while under anesthesia for spay/neuter to allow the jaw to grow correctly on its own, typically a vet will do so.

Under-bite and level bite defined

An under-bite (under shot, reverse scissors bite, prognathism, class 3) occurs when the lower teeth protrude in front of the upper jaw teeth. Some short-muzzled breeds (Boxers, English Bull Dogs, Shih-Tzus, and Lhasa Apsos) normally have an under-bite, many times more than a slight under-bite. When it occurs in medium-muzzled breeds, a slight under-bite or level bite is abnormal.

When the upper and lower incisor teeth meet each other edge to edge, the occlusion is considered an even or level bite. Constant contact between upper and lower incisors can cause uneven wear, periodontal disease, and early tooth loss. Level bite is also considered normal in some breeds, although it is actually an expression of under-bite.

The correct Australian Labradoodle or Labradoodle bite is the scissor bite