AT July-Aug 2005

In Other Words
The Bobtail Trait
in Australian Shepherds
Gemi Sasson-Brickson, M.S. Biology • Enon, Ohio
Part III:
Objectives of the Ongoing Study
(This is the last of a three-part series on the
bobtail trait in Australian Shepherds, written
in relation to my study on the inheritance of
the natural bobtail trait [NBT)[ in Australian
Shepherds. This article addresses the
ongoing study of the inheritance of the NBT
in Australian Shepherds, its objectives and
information relating to study participation, as
well as some preliminaryfindings ofthe study.
Previous articles covered international laws
and regulations and information on genetics
Why
and health.)
is it important to
understand how the natural
bobtail trait is inherited in
our breed and what effect it
might have on neonatal health, if any? In
the initial article of this series, I discussed
the docking bans in various countries. This
movement was initiated by the enactment of
the European Convention for the Protection
ofPetAnimals, which went into effect in the
early 1990s. Inarguably, the main premise
behind these laws is a tenet that docking
violates the moral obligation, and thus the
role as guardian that humans have toward
their animals. Paragraph lib of the German
Animal Protection Act basically states that
it is forbidden to breed animals or change
them through either biological or genetic
measures so that their body parts (organs,
skeletal structure, etc.) will be altered to a
degree that such alteration may inflict pain,
suffering, or damage. Depending on the
evidence available, this could be interpreted
in varying ways. To date, the German law
has mostly been applied to the breeding of
excessively aggressive animals. Already,
there have been a few cases of registries
placing restrictions on the breeding of
two naturally bobtailed parents together,
perhaps due to some of the myths that
were addressed in the second article ofthis
seriesregardinghealth and genetics.Before
we allow such restrictions to creep further
106 AUSSIE TIMES I July-August 2005
into various registries, it is imperative to
study whether or not these precautionary
measures are warranted. That is one of the
things this study attempts to do.
• In the United States, where docking
is routinely performed on Aussie litters,
whether or not a dog is NBT is normally
not a factor when deciding which dogs to
continue with. Although a few decades
ago more emphasis was probably placed
upon retaining the NBT, today American
breeders are looking at many other things
like structure, perceived breed type,
situation-specific working traits, and
performance potential, and health issues
such as juvenile cataracts, epilepsy, and
hip dysplasia.
A
natural bobtail is
actuaiiy a beneficiai
feature for a dog
gathering iivestock
out of the brush.
In Europe now, some breeders are
selecting away from the NBT, whether
through individual preference or demands
from buyers for a full tail, or due to
restraints in breeding options. Conversely,
other European breeders have opted to try
to preserve the NBT whenever possible as
the identifying characteristic within the
breed that it is. After all, a natural bobtail
is actually a beneficial feature for a dog
gathering livestock out of the brush in that
there is no extra hair there to mat or collect
burs. With a considerable percentage of
the breed possessing the NBT trait, either
breeding toward or away from NBTs has
the possibility of having a definite impact
on which individuals are retained within
the gene pool and, consequently, the
other traits that they will pass on to their
offspring. This selective pressure poses
the potential for what's called "genetic
drift'". Maintaining genetic diversity
does provide for more variability in any
species—and this can be both a good or bad
thing. Selectiveness gives us uniformity.
Variety gives us options. Both have their
price. The more selective a breeder is about
pulling in or weeding out a certain trait, the
more alike the products of their breeding
will be. But doing so will also further
concentrate other traits, good and bad, as
it is not within anyone's power to sort out
genes from each other as if one were mixing
ingredients in a recipe. As someone who
purchased their first Aussie nearly 20 years
ago, I have seen the predominant concerns
about the breed shift and alter through the
years. While certain concerns such as poor
temperament or debilitating health defects
certainly merit the utmost regard, breeders
must always keep in mind the complexity
of genetics and just how many possible
gene combinations we are dealing with
when we cross two individuals and get ten
puppies. I mention this because of those
European breeders who have reported that
many of their requests are for full-tailed
puppies. I find this a sad situation because
there are and have been so many bobtailed
Aussies who have contributed positively
to our breed. Do I think, therefore, that we
should start concentrating on getting more
NBTs so we don't lose that trait? Certainly
not. WhatI am saying is that we should look
at the complete picture, full-tail, half-tail,
or no tail, when choosing future breeding
prospects.
So what does it matter if NBT x
NBT breedings are not allowed in certain
countries? Or even if breeders just choose
not to do them? What happens is that a
breeder's optionsare reduced.If the bobtail
trait in Aussies is indeed a dominant one,
as it is in Pembroke Welsh Corgis, that
means that a fairly large number of our
dogs are genetically NBTs. If one can't
or chooses not to cross two NBTs, what
might have been the best overall choice