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Breeding 101 (Continued)

As noted above, genes occur in pairs � one coming from each parent. When different genes (dominant+recessive) pair together they are known as heterozygous genes. When two genes of the same type (dominant+dominant and recessive+recessive) pair together they are known as homozygous genes. Two parents with identical sets of homozygous genes will produce pups with genes identical to themselves.

Inbreeding (mating two directly related dogs), or close line breeding (mating two dogs related within two generations), decreases genetic variation and increases homozygosity � which increases consistency among a litter. The more pups are genetically like their parents, the more likely they are also to be like them in appearance, temperament, ability, etc. This is an attractive quality for big breeders turning out lots of pups � they can be sure of the qualities and characteristics of their pups.

However, increased homozygosity also increases the likelihood for expressed genetic maladies in a litter and line. Most genetic abnormalities and diseases occur on recessive genes. They are not normally expressed in a heterozygous gene pair because the dominant gene cancels them out. All dogs have a great

number of these pairs of bad recessive genes masked by good dominant genes. When you increase homozygosity, you increase the likelihood that these recessive genes will pair up � and the pups will wind up with undescended testicles, hip dysplacia, incorrect bites, hypoglycemia, epilepsy, etc. This is why inbreeding and close line breeding is best left to the experts that are so inclined.

There is a complicated mathematical formula to measure homozygosity called the coefficient of inbreeding (COI). This formula is available on some veterinary websites. Many breeders use the COI to help them keep that balance of desirable homozygosity and genetic variety.

TAKING STOCK

Assessing the strengths and weaknesses of breeding stock is much of what makes breeding an art rather than a science. It requires a keen eye, and an ability to detach oneself from any emotional baggage about an animal and to make an impartial assessment of a dog. It's what makes the great breeders great.

I always advise a novice breeder to use a Zen approach to this aspect of breeding. Close your eyes and envision the perfect hunting dog for the type of hunting you do. How does she move and range? What type of temperament does she have? How does she handle? What type of build and coat does she have? Does she have good conformation within the breed standards? Assemble a mental checklist of those qualities typically affected by heredity that this ideal dog possesses. . The qualities I tend to focus on are (not in any specific order) as follows:

- Natural Pointing&Retrieving Ability
- Nose
- Range
- Conformation
- Temperament
- Biddability
- Intelligence
- Drive
Now open your eyes and look at your bitch and make a comparison to that ideal dog. How does your bitch measure up? Assign a number from one to ten to each of the qualities you identified, and be brutally honest.Once you�ve rated your bitch this way, you�ll have a good idea of her strengths and weaknesses, and where you need to go in your breeding. If she scored well on the checklist then

You can see the similarity in conformation between Annchen (with the red collar), and her pups. There's no mistaking these dogs are related!!

you are set to take the next step.

The next step is getting a medical assessment of her health. Waiting until your bitch is two gives you the opportunity to have her hips x-rayed for OFA or Penn Hip certification. Hip dysplacia is a relatively common genetic disorder that can be identified through a special review of hip x-rays. For breeds with known problems with HD, all breeding stock should be certified HD free before breeding. Depending upon the breed, screening for a variety of other genetic disorders might be recommended. She should also be tested for brucellosis. It is best to discuss with your vet what tests might be appropriate for your breed.

Now that you have determined that you have a bitch that performs well in the field, has good conformation within breed standards, is medically sound, and has the personality characteristics you would want in your pups - the next step is to find a stud. (continued)

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