The bobtail trait is inherited as a dominant gene. Only one bobtail parent is required in order for bobtail pups to be whelped. On average, when breeding 1 bobtail parent and 1 longtail parent, 50% of the pups in the litter will have a bobtail.
The bobtail gene can not be inherited as “homozygous”. Meaning that a bobtail dog can not carry two bobtail genes (one inherited from each parent).
The bobtail gene is inherited as “heterozygous”. Meaning that a bobtail dog has 1 bobtail gene and 1 longtail gene.
Therefore when breeding two bobtail dogs together, there will still be both longtail and bobtail pups in the resulting litter. On average there should be 50% bobtail pups with this breeding.
The bobtail gene in Catahoulas (as with most other Cur breeds) has a “variable expression”, meaning that the length of the bobtail can range from a very short stub to a ¾ length tail, although on the average the bobtail is from 1 – 3” in length.
A longtail dog from a bobtail parent will not produce any bobtail pups when bred to another longtail dog. If a pup does not inherit a bobtail gene from a parent then the trait is forever lost in that pup...it can not be passed on as a “recessive” trait.
Out of eight associations, only the NALC faults the natural bobtail.
The Animal Research Foundation was the first to register the Catahoula in 1951. The bobtail dogs have always been included in their standard.
Note: Mr. Vernon Traxler was the first to registered a bobtail Catahoula with the ARF.
Mr. Traxler - “Traxler Catahoulas” had been breeding bobtail Catahoulas since 1944. His first bobtail Catahoula was acquired in a trade with the Indians at Three Rivers, south of Jonesville, LA - a yellow, glass eyed female.
When the NALC started up in 1975, the bobtail trait was not faulted. This fault did not come into effect until 1985. In 1995 the standard was revised to make the bobtail a serious fault.
Most Cur breeds have the natural bobtail trait. This trait is accepted by the various Cur breed clubs and organizations.