In this second part of my article I will share some basic knowledge I have gleamed through the years and I hope I can explain them simply and accurately. What follows is based on my own experience and knowledge, both are somewhat limited and both are subject to change every time I breed.
HEREDITY (Genetics)
You hear lots of talk about heredity, which is the study of genetics. Regardless of what you may read on the subject, the fact remains that in 99% of the breeding you will do, 75% remains luck and 25% will be acquired skill. You can through selective breeding eliminate faults and introduce superior qualities with a combination of careful selection and a basic understanding of heredity. Keep these things in mind: Even with new developments in DNA and RNA research in cracking certain codes in the language of heredity, this science has not yet been perfected to the point of creating superior mice, men or dogs. Research has made giant leaps in areas of birth defects and some inherited diseases. Your best results still come from application combined with the continued discoveries of the dedicated geneticists who have aided us through years of breeding to help establish some of the more dominant genes as well as recessive genes. To understand heredity one should recognize the following:
- A dog's true qualities are not always seen in his physical appearance. This physical type (referred to as the Phenotype in genetics) is often concealed in his genetic makeup (Genotype). Quite simply, "Don't judge a book by its cover." IF YOU CAN REMEMBER THOSE TWO TYPES, YOU WILL BEGIN TO HAVE A RAW BUT BASIC KNOWLEDGE OF HEREDITY. How many of us have seen a bitch who was not much to brag about in appearance produce outstanding puppies? Although she may not please our eye physically (phenotype) her inherited genes (Genotype) were obviously pure. Often our pedigrees are valuable tools and offer an outline of our dog's genetic makeup. It is important to know your dog's ancestors!
- Everything about your dog is inherited from the way he looks to the way he shows.
- Dominant genotypes and recessive genotypes can seem complicated, but let's just cover a few of the basics. Some breeders believe all good traits are dominant and all bad traits are recessive. This belief is no doubt based on the fact that most faults that are serious or sometimes fatal like a clef palate do not often occur as your desirable qualities. However, traits like lay-back of shoulders, good angulations, good turn of stifle, smooth gait, etc. can also be considered recessive. Genetic traits are established at the moment of conception and once the breeding is done there is no turning back. Hopefully you've done your homework before you bred. With the 75% luck, maybe you have a chance. Through my own experience and shared experiences with other breeders I have begun to build myself a list of what appear to be dominant and recessive faults. They are as follows:
Dominant
poor layback of shoulders
poor angulation
high tail set
heavy bone
deep brisket
straight topline
good rib spring
short stifle
normal hearing
good mouth
normal palate
normal lip
black masks (fawn/brindle)
low ear sets
course skull
a dark eye
a normal eye
brown eyes
short coats |
|
Recessive
good layback of shoulders
good angulation
low tail set
light bone
shallow brisket
sway back
poor rib spring
long stifle
deafness
over or undershot mouths
clef palate
hare lip
white
high ear sets
fine skull
light eyes
bulging eyes
blue eyes
long coats |
Breed with caution and always remember that just because a particular trait is recessive, does not mean it will automatically yield to the more dominant gene. Equally important to remember is that any dog or bitch who exhibits a desired trait or characteristic recognized as coming from recessive genes indicates the dog must have inherited this gene from both parents, in other words, the dog got a double dose. The dog is considered "pure" for this characteristic and can only pass on the recessive gene to the next generation. The dog simply does not have the dominant gene and is considered homozygous (the double dose) for this trait. If the dog is bred to another dog who also displays the same trait, they will always breed true. A recessive gene is not an inferior gene but one that is simply restrained. Done right a recessive gene can develop into a strong ally in your breeding program. Let me give you an example of this application. Years ago what I refer to as my particular type was set quite by accident. I will explain later in this article the circumstances. Most of my dogs exhibit good fronts (layback of shoulders, etc.) along with a few other desirable traits. In an inbreeding situation (mother to a son) I discovered that both possessed the recessive gene for a good lay back of shoulders and the other traits. Both dogs displayed the traits physically as well. The third dog involved, the son's sire, also possessed the physical (phenotype) attributes as did his sire.
Because I never saw his mother, I can only assume that at least one of them genetically possessed the traits as well. In any event the inbreeding of a mother to a son "locked in the recessive genes." This recessive gene in my breeding program has enabled me to maintain these same traits (shoulders, etc.) generations away from the original pair of dogs. Their offspring bred true for the traits as have the subsequent generations that followed. In all cases this "locking in" can be accomplished with attributes like a lay back of shoulders, angulation, turn of stifle, etc.
PEDIGREES
Consider your pedigree as a receipt of the dogs genetic past. Don't just look for names. Just because Betty Crocker's name is on the recipe does not mean, the dish will turn out well. How you interpret and mix the ingredients is equally as important. The pedigree should be our list of ingredients.
A pedigree should tell us something about the breeding system being used. It can reveal how a particular dog was produced and what qualities may be passed on to future generations. A simple understanding of the mechanics of heredity can turn your pedigree into a very reliable record.
Most pedigrees provided by breeders consist of 4 to 5 generations including 30 to 62 dogs. Each of these dogs possesses genes neatly arranged in 39 pairs of chromosomes. Any of them are capable of expressing a desirable or undesirable trait in your dog. Generally we assume that a dog receives ½ of his genes and chromosomes from his sire and ½ from his dam. You must also take into account that 1/4 of this combination can come from one of his 4 grandparents and 1/8 can come from his great-grandparents and so forth. It would assume correct, therefore, to believe that a dog's immediate ancestors (parents and grand parents) should influence the pups to a greater degree than those further back in the pedigree. However, it is not impossible for a dog to inherit one or more desirable or undesirable traits from an ancestor back in his 6th or 7th generation. With the advantage of breeding and seeing several generations of your own particular stock, you can begin to detect the influence of past generations. You should also be able to see any new influences as well.
When you come across a dog with what is considered and Open Pedigree (a dog's name will appear only once), in say a five-generation pedigree, you get can inherit both physical and genetic qualities from 62 different dogs. To attempt a breeding program from this type of pedigree is really doing it the hard way. I'm not saying it is impossible to achieve success but most of us don't have the time it will take to accomplish such an endeavor.
Therefore, for breeding stock your best bet is to turn to an experienced breeder, who has through their breeding program reduced the number of dogs in a five-generation pedigree. They should have built a gene pool by discarding poor quality dogs and replacing them with good quality dogs giving a new breeder the advantage of their experience and hard work.
I have reached the end of my notes (this article has been spinning in my head, with notes scribbled and left in a drawer for a long time. I hope it is received in the spirit I intended, to help all of us get a better understanding of effective breeding. I also hope in someway it will help someone in their pursuit of breeding, showing or simply loving that "special" Boxer. At the beginning of this article (Part I) I stressed, "I am not an expert. I'm just an old war horse with some practical experience." Good luck and I sincerely wish you well. I leave the Boxer, my heart's passion, in your hands.
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