Usenet 1993 July/InfoMagic USENET CD-ROM July 1993.ISO/answers/dogs-faq/breeding

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From: [e-mail] (Cindy Tittle Moore)
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Subject: rec.pets.dogs:  Breeding Your Dog FAQ
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Summary: This introduces the reader to the difficulties of breeding dogs.
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Archive-name: dogs-faq/breeding
Last-modified: 15 April 1993


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BREEDING YOUR DOG

A.  Reasons NOT to Breed.  Reasons to Breed.
B.  But My Dog is Registered!
C.  Medical Checks for Breeding Stock.
D.  Temperament.
E.  Pedigrees.
F.  Frequency of Breeding.
G.  Care of Pregnant or Nursing Bitch.
H.  Caring for the Puppies.
I.  Considerations for Stud Dogs.
J.  Genetics.
K.  References.


You may be wondering whether or not you will breed the dog you get.
Here is some information.  The summary is that if you want to do it
right, and get healthy and happy puppies, it is very expensive and a
lot of work.

Remember that you are going to need a vet that is familiar with
whelping dogs.  This will be your best resource, as well as any
long-time breeders that you know.  Not all vets are knowlegeable
about whelping so be sure to ask around and especially look for
recommendations from local breeders that you may know.


A.  Reasons NOT to Breed.  Reasons to Breed.

Please do NOT breed your dog "for the money" or "to see the wonders of
birth and life" or some similar nonsense.  Breeding is expensive, and
good breeders rarely make money on their dogs.  The "wonders of birth
and life" can turn tragically if any die; if the bitch has her puppies
at the vet, the kids certainly won't see it.  Dogs and bitches are NOT
improved or fulfilled by having puppies.  They are not frustrated in
life by the lack of puppies either.

If you want to breed your dog so as to get another dog like yours,
think about this for a moment.  No matter how special your dog is to
you, a puppy out of it is not guaranteed to be just like or even
similar to your dog -- half it's genes are from another dog!  You will
have to find another dog that has the characteristics you want in your
puppy; that dog will have to be unneutered; and the owner of that dog
will have to be willing to breed her/his dog to yours.  It is much
easier, often less expensive, and certainly less time consuming to
pick out an existing dog that you like from the shelter or another
breeder.

Don't breed for the money.  If you do things right by the parents,
puppies, and people who buy your puppies, you are very likely to
*lose* money.  Good breeding is expensive.  There are health tests to
ensure that the parents are healthy and fit.  There are expenses
related to feeding and care of the dam and her puppies.  There are
possible expenses if there is trouble with the litter.  The process is
time consuming: days off from work, time spent caring for the puppies,
time spent socializing the puppies, time spent training the puppies,
time spent talking to puppy buyers on the phone, time spent showing
puppy buyers the puppies, etc.  There are even potential problems
later on with dissatified customers!  You are better off consulting
with a financial wizard about investing the money you would otherwise
spend and lose on breeding!

The ONLY reason you should be breeding is that you honestly feel that
you are improving your breed by doing so.  There are far too many dogs
in the country to breed without good reason.


B.  But My Dog is Registered!

Well, yes, but that doesn't mean a whole lot.  A registered dog, be it
AKC, UKC, CKC, etc., simply means that it's parents (and their
parents) are also registered with the same registry.  This confers no
merit in of itself, it simply means that the dog's parentage is known.

Registries do not make any assertions of quality in the dogs they
register (except for some limited breed-only registrations, but these
are uncommon).  They do not restrict the breeding of their dogs and
hence there is no guarantee that a registered dog is a good specimen
of its breed.

The AKC has just started a "limited registration" program whereby
puppies out of such dogs are ineligible for registration.  It remains
to be seen what the overall impact on AKC dog breeds will be.


C.  Medical Checks for Breeding Stock

1.  Eye checks

Eye problems include PRA (Progressive Retinal Atrophy -- causes total
blindness), which doesn't usually show up until the dog is 4 years
old, cataracts, and retinal dysplasia.  These are hereditary
conditions and in some cases cause blindness.  In the case of PRA, the
pedigree needs to be studied, and if there are any carriers of the
disease on her pedigree, you must choose a stud dog whose pedigree is
free of any problems.  PRA is a recessive gene, so in order to be
affected the puppy needs to get a gene from each parent.

CERF (Canine Eye Registry Foundation) registers dogs that are found
clear of eye problems.  Dogs need to be cleared yearly as there
are some types of eye problems that show up later in life.

2.  Hip and joint checks.

Hip problems are more likely.  There is a hip certification process
that breeders adhere to, and have their dogs certified free of the
disease by OFA.  OFA will not certify a dog until that dog is 2 years
old so it's best to wait until that age to certify and then breed if
all is well.  They grade the hips as a passing grade of Excellent,
Good, or Fair, or a non-passing grade (meaning DO NOT BREED this dog)
of Borderline, Mild, Moderate, or Severe hip dysplasia.  Even if your
dog's parents are OFA certified you need to certify its hips as well.
In a breeding of OFA certified parents, you will get a range in the
quality of the dogs' hips.  Even the worst aren't likely to show any
symptoms of hip dysplasia, at least not as young dogs, but if you
breed two borderline dogs together you may get a litter of crippled
dogs.  The hip problems aren't limited to the puppies either.  In
addition, borderline bitches that are bred wind up with hips that
deteriorate faster than they would have otherwise.  So you could also
damage the health of the dam by breeding her when her hips are
borderline.

There are increasing problems with elbow dysplasia in many of the
breeds that have hip displasia.  In addition, there are other joint
problems that affect other dogs.  For example Pallelar Subluxation
(where the knee cap will slip to one side and lock the leg into
position) is a common problem in smaller breeds.

Arthritis, calcium buildup and other problems should also be checked
for.

3.  Breed specific problems

Other breeds have a tendency toward other specific medical problems
(hip and eye are simply the most common): you need to know what is
prone in your breed and take steps to minimize and eliminate it.

Some examples are deafness in Dalmatians, cardiac problems with
Newfoundlands.

4.  Other things to check for

You must make sure the bitch and the stud both are free from
brucellosis before breeding them.  Brucellosis causes eventual
sterility in both sexes (sometimes non-obviously) and can cause a
litter of puppies to be aborted or die shortly after birth.  In
addition, brucellosis is on occasion transmissible to humans via the
urine or feces of an affected dog.  Between dogs, it is most commonly
passed in sexual intercourse, although an entire kennel can be
infected through contact with secretions.

Epilepsy, siezures and similar problems should be ruled out.

Vaccinations must, of course, be kept up to date.


D. Temperament

Never breed any animal that has temperament problems.  In particular,
this has been the cause of the degeneration of many breed's general
temperament: Doberman Pinschers, Rottweilers, and so on.  If your
animal is untrustworthy around people, overly aggressive to people,
excitable, or is a fear-biter, do not breed it.  If it is shy or
submissive, don't breed it.  Look for happy, confident and obedient
animals, and consider carefully the particular temperament
requirements for your dog's breed.

There are a variety of tests to indicate a dog's temperaments.  Many
of the working breeds have a temperament test (for example, the
Doberman's WAC test) for their breed.  AKC has a Canine Good Citizen
test (open to all dogs) that gives some indication of the dog's
temperament (and, yes, training).  Therapy Dogs International and
other Therapy Dog clubs have temperament testing that does try to
separate out actual temperament from training.  Obedience titles can
be (but are not necessarily) an indication of good temperament.


E.  Pedigrees

You must carefully consider each dog's pedigree for compatibility.
Try to select strengths to offset weaknesses.  Do not allow your bitch
to be bred to an unsuitable dog, and conversely, be picky about the
bitches you allow your dog to breed.  This phase alone requires
considerable research to find a suitable candidate, and you should
definitely work closely with a knowledgeable person, ideally the
breeder of your dog.  Simply because two dogs "look good" or even
*are* good does not mean that they necessarily complement each other:
suppose they are both carriers for the same disease?  Suppose they
both have a tendency to overbites or other disqualifying faults?

Be honest with yourself.  If your dog is not a good representation of
its breed, do not let it reproduce.  It is much easier to improve a
few faults than to try and get excellent pups with a mediocre dog.
Check the breed standard for your dog and ask a knowledgeable person
for their evaluation of your dog.

We'll return the the importance of scrutinzing a pedigree in the
genetics section later.


F.  Frequency of Breeding

Ideally, a bitch should only be bred every other year and she should
not be bred much before two years of age.  The season closest to the
second birthday is a good one to start with.  By this time, she is
better prepared mentally for having puppies than she would have been
with her first few seasons.  Her physical growth is complete and
pregnancy at this point won't endanger her health, provided that
she is healthy to begin with.

In breeds with Hip Dysplasia, many people wait until after two years
of age so that the bitch is certified; however if you have sent in
xrays to OFA for preliminary certification and they came back as fine,
many breeders consider it safe enough to then breed on the season
closest to the second year, which can wind up being before the bitch
is actually old enough to be certified.  But the preliminary xrays
*must* be examined by OFA, not by a local veterinarian.  There are
many, many dysplastic dogs out there that had vets look at their xrays
and pronounce them "wonderful."a

However, even at maximum, you want to allow at least one unbred season
between breedings.  This allows your bitch to rest and regain her
strength.  A bitch that whelps too often will produce weaker puppies
more likely to die, and the repeated pregnancies are pretty rough on
her, too.

For dogs, they should definitely have all their certifications
necessary.  For many breeds this means that they should be over two
years old.  Since a dog can be bred at any time, unlike bitches,
waiting for two years is not a problem, whereas a bitch often has a
season just before two years of age and then has to wait until 2.5 or
three which sometimes presents problems in trying to time her litters.
But this does not apply to a stud dog, so he should definitely have
all of his checks and certifications before being bred.  Frequency is
not generally a problem although some dogs have problems with sperm
production if they breed once a day for several days.  They need
top-quality feeding and care if they are going to be bred often.


G.  Care of the Pregnant or Nursing Bitch

You should make sure the bitch is up-to-date on all her vaccinations,
medications, and shots before she is bred.  She will require
supplementary food during the last three weeks or so of pregnancy.
In general, puppy food is formulated both for puppies and pregnant
or nursing bitches.

She should be under the care of a vet for any related problems.  Dogs
can have miscarriages.  Illnesses, diseases, or infestations that the
bitch picks up during her pregnancy can affect the puppies.
Difficulties during whelping are entirely possible, and the rule for
some breeds.  You must be prepared to get her to the vet quickly in an
emergency.

There are instances of "mummy puppies" where you have a puppy whose
development went awry, but it was not aborted.  Instead, it dries and
shrivels up, and when born, looks like a mummified puppy, blackened
and ready to rot.  Overbreeding and inadequate care are usually the
causes.  It is quite likely that the dam will come down with an
infected uterus after such a puppy.

Other congenital (but not genetic) defects can include: no anus, cleft
palates and hare lips.  These conditions require corrective surgery or
the puppy will die.

While the bitch is nursing the puppies, she will require about three
times the amount of food she normally requires!  It is common for
nursing mothers to go out of coat at this time.


H.  Caring for the Puppies.

1. Postnatal care

You do have a whelping box, right?  You should have a sturdy, clean,
proper sized whelping box for the litter.  It MUST include a
"pig-rail" around the edge to prevent the bitch from laying on or
smashing her pups.  It should be big enought to allow the bitch to
turn around but small enough to prevent the pups from being "lost" in
the unused portions.

Newborn puppies MUST be kept warm.  The temperature in the welping box
at birth should be 90 F.  The temperature can then be decreased 2
degrees every other day.  NEVER FEED A CHILLED PUPPY!!!  If a puppy
becomes chilled it will cry continually and it will tuck its tail
between its little legs.  A healthy, happy, litter with "purr" like a
swarm of bees and when feeding their tails will be straight out from
their bodies.  Warm any chilled puppy by putting the puppy under your
shirt and under your armpit.  The best method of warming a puppy is to
use a special whelping box heating pad with a towel over it to prevent
soiling the pad.  Make sure the temerature does not go too high.
Heating lamps are ok but puppies can become dehydrated.

Large litters will require supplemental feedings if you want all the
puppies to survive.  Your bitch may not be able to care for a very
large litter.  You will need to get the pups rotating on shifts.  For
the first two weeks you may have to supplement as much as every four
hours.  Use a good prepared milk-supplement especially formulated for
puppies.  If you get in a bind you can use a goat-milk reciepe
avilable in most books about breeding and whelping pups.  You may have
to tube feed those pups that will not suckle from a bottle!

Are you going to remove the dewclaws or dock a tail?  This must be done
by 3 days old MAX!  Any later will not heal as nicely or quickly!

If you have a purebred litter, you must record the date of birth and
all of the pups (including the dead ones) in your record book.  Then
you will need to fill out and send in your litter registration form.
You want to do this as soon as possible, since many registries can
take up to 6 weeks to return the forms for individual registration to
you.

You will have to keep the whelping box clean.  For the first two weeks
the bitch will keep the pups pretty clean, but the bedding should be
changed twice a day at minimum.  Starting week three, the pups start
to eliminate some on their own.. then you will need to clean much more
often!!!

At four weeks, the pups usually become very active and it this time
may require a larger area then the welping box...you will need a large
ex-pen or some way of confining them safely.  You do have a place to
keep them that they are safe in and can't destroy?  Puppies at this
stage can devastate a room or garage in hours.

At week five you will probably want to introduce the pups to weaning
food.  Usually you will have to mush up the dry puppy food for the
pups to be able to eat it.  Use warm water and let the food stand in a
bowl for about 2 hours.

At week six you should vaccination and worm the pups, and have them
checked for heartmurmers, hernias, males for testicles (yes you should
be able to feel them at 6 weeks!), deafness, and eye problems.

You should be socializing now too... And are you going to do any puppy
testing for temperaments?  At seven weeks you should be calling up
those poeple with deposits on your pups and getting your paper work
all sorted out.  Are your spay/neuter contracts ready?  How about
pictures of the pups for your clients?

And this is just if everything goes perfectly!  What happens if one of
the pups has a heart murmer, or a hernia?  What about a deaf puppy?
What if your whole litter gets parvo or distemper?  What happens if
one of the pups is affected with "Swimmer-puppy" syndrom?  What about
fading-puppy syndrome?  What happens if your bitch gets an infection
or mastitis?  What if she dies?

2.  Placing the puppies

After the puppies are born, if not before, you must consider placing
your puppies.  Time and time again, people breed a litter because
friends and family want one of their dog's puppies -- and then none of
them will take one.

Eight weeks, you may begin placing those pups that are ready to go to
their new homes.  Insecure pups may need more time, how are those
puppy tests coming?  You can't place puppies earlier than 7.5 weeks or
so (no matter how much you may want to).

Are you prepared to do some legwork to find GOOD homes for them, not
just hand them off to the first person who comes by?  You are aware
that you won't always be able to sell all of your puppies locally,
aren't you?  What assurances do you have that the puppies will not
wind up filling animal shelters, facing death because their parents
were thoughtlessly bred?  Suppose you wind up keeping more of the
litter than you intended to?  Suppose some of your puppies are
returned?  Can you keep the extra puppies?


I.  Considerations for Stud Dogs

Your male should be in top condition.  He should be certified clear of
hip dysplasia (which means that he must be at least two years old).
His eyes should be checked annually.  He should be clear of any
abnormalities common to his breed.  No heart problems, no seizures, no
thyroid problems, etc.  He should be clear of brucellosis.  His
temperament should be good, and appropriate for his breed.  If you
have such a dog, you will need to get your dog well known.  This
generally involves showing your dog (in show, field, or obedience) and
doing other work with him.  An unproven dog (that has no previous
puppies or only puppies too young to evaluate) will command a much
lower stud dog fee than a proven dog (with a record of puppies to
examine).

You must be prepared to board the bitch.  The common procedure is for
the bitch to be shipped out to stud, so you will need facilities to
board bitches in heat.  These facilities should be adequate for up to
a week of boarding and to prevent any mismating.  You might wind up
with more than one bitch at a time -- can you board them all safely?

You must monitor the mating and be ready to intervene if necessary.
Not all dogs or bitches understand what to do, especially if it is the
first time for one or the other.  It can be disastrous if two dogs are
left alone to mate.  Additionally, if the mating doesn't take, are you
prepared to go through the whole thing again the next time the bitch
comes into season?  Typical contracts call for free repeat breeding in
the case two or less puppies occur or the breeding doesn't take.

You need to be able to evalate the bitch's pedigree for compatibility
with your dog's.  Any good points or bad points of the litter are
(rightly or not) attributed to the sire, so your dog's reputation is
at stake with each litter he sires.  You should be reasonably
confident that the proposed breeding will result in good puppies.

If the owner of the bitch is a novice, are you prepared to assist with
advice on whelping and puppy care?  These people will expect you to
have the answers.  Sometimes entire litters of puppies are dumped on
the stud dog owner when the bitch's owners can no longer cope with
them because they didn't realize what a responsibility caring for a
litter involved.  Are you ready to take care of and place your dog's
offspring if this should happen to you?

Are you prepared to deal with cases where you are certain your dog is
not the sire of the puppies but the bitch's owner insists that he is?
Or if the owner of the bitch insists that you must have allowed a
mismating to occur when she was boarded with you.  Disputes of this
sort can become very ugly very quickly.


J.  Genetics.

1.  If a purebred dog of breed X mated with a purebred dog of breed Y,
both meeting health standards for their breed, is there a better
chance the offspring would be healthier than a same breed mating
because the gene pool is larger?

In terms of health alone the first answer would be that in breeding
two healthy dogs it shouldn't matter if they're the same of different
breeds, you're apt to get healthy pups.  But this doesn't take into
account the question of recessives.

Suppose you breed two dogs of different breeds that both have the same
incidence of a recessive health problem.  The pups would have the same
odds of having that health problem as purebred pups of either breed.

On the other hand, suppose the two dogs were of breeds that have no
recessive health problems in common.  This would reduce or eliminate
the odds of the puppies of having the health problems of either breed.
This is the classic explanation for the theory of first generation
hybrid vigor.  The resulting pups should not be bred though, since
they'd have a good chance of having the recessives from BOTH breeds,
so their offspring would be inclined to be worse off than the purebred
offspring of their grandparents.

Another *very* important point to keep in mind is that when a purebred
carrying a genetic defect is crossed with another breed or mixed breed,
the "bad" genes do NOT "go away" even though they may not be expressed
in the offspring.  If crossed with another dog carrying the same defect,
the offspring of that breeding *will* demonstrate the defect.

Responsible breeders try to identify genetic diseases their dogs might be
carrying and to eliminate them by careful breeding.  It is ironic, though
not surprising, that their efforts to identify and weed out genetic
problems have lead some to cry "look at all the genetic diseases purebred
dogs have!"  A moment's careful thought will lead you to the conclusion
that mixed breeds carry the *same* harmful genes (their parents, or their
parents' parents, *were* purebreds, after all).  The differences are
    * with some recessive disorders (though not *all* genetic defects)
the disease is less likely to be *expressed* (though it can still be
inherited by  offspring)
    * you have lesser likelihood of ever identifying or eliminating any
harmful genes your mixed breed may be carrying.

2.  When you breed two different breeds together, what kind of
variation can you expect?

Pfaffenberger's book has some interesting data on this.  He did some
experiments with four different breeds.  They were dogs of
approximately the same size, but very different physical appearance
AND behavior.  The results he saw in the first and in subsequent mixed
generations are pretty interesting.

3.  What is outcrossing?

Outcrossing is where the sire and dam are totally unrelated,
preferably for three or four generations.  The true form of an
outcross is between two entirely different breeds because in reality
the members of most registered breeds come from a common ancestor
(althought it may be many, many generations back).  It is very rare
for outcrossed puppies to be very uniform in appearance.  Usually
there are a very large ranges of sizes, coats, colors, markings, and
other distinctive characteristics.  This does usually result in a
heterozygous litter (the pups have a wide range of genetic material
spread among them).  This does tend to produce healthier puppies, but
it is not always so.  Also, many of the desired characteristics of the
breed are quickly lost (meaning the pups are not usually show quality
-- although there are exceptions!).  Also, these pups do not tend to
reliably reproduce themselves (which makes breeders even more broke).
If you are dedicated enough, you can eventually continue breeding by
outcrossing alone (but don't expect instant or quick results).  You
should pick dogs that complement eachother well and are similar in
general appearance.  This is a long hard road to eventually developing
a line.  Through outcrossing, many health problems can quickly be
eliminated (or just as quickly added into your breeding), but usually
you do sacrifice some show quality and producibility.

You have to remember that dogs that appear totally healthy may be
carriers of genetic problems.  To find this out, test mating is done
to a dog that is affected with the genetic problem (resulting usually
in puppies that are both affected and non-affected carriers) or by
inbreeding to a related dog that also doesn't show the signs of being
affected (usually littermates are used) this will usually result in
some puppies free of the problem, some puppies as carriers, and some
puppies affected if both dogs carry the problem gene (this is not as
accurate as breeding to an affected dog, but you are less likely to
have to put all the puppies down).

There are variations on outcrossing.  A "true" outcross could be a dog
that has totally unrelated dogs bred together throughout the pedigree.
This is very rare.  "Linecrossing" is a form of outcrossing where dogs
from unrelated lines are bred to produce a new line.  The sire and dam
are usually very linebred from their prospective lines and the
resulting puppies are varied in appreance, some looking like the
sire's line and some looking like the dam's line and some looking like
mixtures of both lines.

4.  How about line breeding?

Line breeding is when the sire and the dam are distantly related:
e.g., grandsire to granddaughter, granddam to grandson, second
cousins, half cousins, uncle to niece, aunt to nephew.....  This is
the most common form of breeding in purebred dogs.  Though this
breeding strategy, new genes are slowly introduced and unwanted genes
are slowly replaced.  This method sacrifices little overally quality
in terms of show quailty.  Usually the puppies are rather close in
general conformation.  The only problem with this method is that it
often takes several generations to get poor genes out, (or adding
desired genes in) resulting in many puppies that have the same genetic
problems (or virtues) that their parents have.  Because some breeders
are more interested in winning, they do not place the affected puppies
on spay/neuter contracts.  This is both a blessing and a curse for the
breed.  If the breeder is very careful, affected pups can be used
wisely to prevent loss of quality, but still remove the affected genes
by only breeding the affected pups to known non-carrier relatives.
This way the breeder can again try to "edit out" the bad genes.  It
takes longer this way but less show quality is lost in the process.
This process results in dogs that will often reproduce their same
level of quality.  This is refered to as reaching homozygous litters
(more genes of the same kind apparent in the puppies).

Inbreeding and linebreeding differ only in degree.  Linebreeding is
less likely to cause harm than inbreeding.  Inbreeding is not for
novices.  Knowledge of genetics and the breed is required for success.
For good results it must be well-planned and breeders must be ready
for whatever problems it presents.

5.  And inbreeding?

Inbreeding is where the sire and the dam are closely related: mother
to son, father to daughter, sister to brother, half sister to half
brother, cousin to cousin.  It is the quickest way to find out what
poor genes are in the line and what dominant characteristics are in
the line.

Although many people are disgusted with the idea of this family
incest, it is an extremely useful tool for diagnosing what genes are
present.  If the genes for bad eyes are present, but hidden or
resessive, this will bring them out to their full extent.  If there
isn't any bad genes, then the puppies will be of very close uniformity
and very able to reproduce themselves (theroretically).  This is a
homozygous breeding.  The resulting puppies will have a lot of genetic
material that is the same as their parents and grandparents and will
be close genetically to each other.

Inbreeding doesn't introduce new genes and does not eliminate bad
genes that the line already has.  It only shifts them around like a
rubix cube.  This often results in litters with high show potential.
But there are drawbacks.  Inbreeding exclusively will eventually lead
to infertility.  It's like a xerox machine.  After so many copies, you
have to renew the ink.  The same with dogs, you have to introduce new
genes.

Inbreeding increases the chance that a gene obtained from the sire
will match one obtained from the dam, both stemming from the common
ancestor(s) on which the individual was inbred.  Thus, inbreeding
tends to make animals homozygous rather than heterozygous.  The
inbreeding coefficient measures the resulting increase in
homozygousity.  All breeds have a given degree of homozygosity the
mating of two dogs from the same breed would not produce a
recognizable specimen of the breed!

Inbreeding can increase homozygosity and decrease heterozygosity.  So
it can duplicate both desirable and harmful alleles, both of which can
be unsuspected in the line, and may appear.  Inbreeding does NOT
create anomalies, it brings present anomalies to the surface.  Even
when the anomalies are present, inbreeding might not reveal them.

An increase in harmful recessives is undesirable but it is not a major
drawback if they are identified early.  The effect of inbreeding on
major polygenic traits is greater.  Generally, traits that are highly
inherited (ie largely additively controlled) are not adversely
affected by inbreeding but, traits under non-additive control,
especially those tied to dominance and thus not of high heritability,
are often markedly harmed by inbreeding.

An inbred bitch produces outbred offspring when bred to an unrelated
sire and an outbred bitch whelps inbred progeny if bred to a related
sire.

5.  OK, how do pedigrees figure into this?

Remember that it is difficult to spot unaffected carriers.  When an
affected dog shows up, its pedigree is often examined for likely
carriers.  For example, PRA is a common problem in many breeds.  There
are dogs that come down with PRA that have a certain ancestor in
common.  That ancestor may then be considered a possible carrier and
line breeding on him is avoided.  This is a simplistic picture,
obviously, since it's possible for an unaffected non-carrier of
PRA to come from an unaffected carrier that came from an affected
dog (therefore the affected dog is in the unaffected dog's pedigree).
If a blood test is ever developed that shows the presence of
the recessive in an unaffected dog, then much more accurate
breedings may be done.

There is rarely only a single problem a breeder is trying to screen
for.  Suppose a suspected carrier of PRA is known for producing
excellent hips.  A breeder might therefore introduce that bloodline
into theirs for the hips, and be willing to have the possibility of
PRA show up in the line.  In screening out one problem you might
have to accept the possibility of another appearing.

Examining the pedigrees also lets you know what percent of ancestry
the dogs share (since the relationships are often much more complex
than simply cousins or aunt/uncle, the degree of common ancestry
is often given as a percentage instead) and decide whether or not
it's acceptable given your current goals.

6.  What are like-to-like matings and compensatory matings?

Like to Like: Like to like mating implies the best to the best and the
worst to the worst where the worst is not used at all.  For most
breeders, like to like matings are between dogs which resemble each
other greatly and so similar type dogs are bred.  These dogs may or
may not be closely related.

The pups resemble their parents because of the genes in common with
them.  If those parents resembled each other their progeny would be
even more like their parents.  This tends to make the population look
more uniform, however there is little increase in prepotency from this
technique.

Compensatory Mating: This unlike to unlike mating is used by breeders
to correct for a defect in an animal by mating it to another animal
that might correct for the defect.  The system is basically simple but
the breeder must identify faults and virtues and it requires breed
knowledge.  The pedigrees of both dogs should be examined carfully to
try to identify the ways in which the dogs differ and what the
expected outcomes could be.  A correct dog and not one who errs in the
opposite direction is required. That is, if you want to improve
structure, look for a dog with correct structure and not an overbuilt
dog.  This technique often results in only one or two pups with the
combination desired.

7.  But this is all very vague and complicated!

Yes, it is.  There are no easy answers, and there are different things
to consider in every breed.  This uncertainty with respect to genetic
inheritance is exactly the reason that breeding is so difficult to do
right.  It helps immensely to have a "mentor", someone who is familiar
not only with the breeds, but the lines your dog belongs to -- advice
from such a knowledgeable person is often extremely valuable.

If we knew everything about genetics, we wouldn't *have* problems with
our dogs any more.  We'd eliminate Hip Dysplasia, PRA, heart problems,
thyroid problems, seizures, etc. within a few generations if we knew
everything.  Unfortunately it's an art that few people are actually
very good at.


K.  References.

"So you want to use your Dog At Stud?"  From the Literary Spot, the
newsletter of the Central MD Dalmation Club 12/89 via Retriever
Believer, the newsletter of the Labrador Retriever Club of Southern
California 8/91.

Tucker, Kathy.  "Why are you Breeding?", printed in various newsletters.

Whitney, Leon E (DVM).  _How to Breed Dogs_ 384 pg. Many case studies
on breeds, breed crosses for dominance studies, Myths and fallacies
about breeding dogs, inheritance of traits (such as temperament,
health, intelligence, and abilities).

Wilcox, Bonnie (DVM).  "Things to Think about Before Breeding Your Dog."
DVM, printed in various newsletters.

Willis, Malcolm B.  _Practical Genetics for Dog Breeders_.  Howell,
1992.  228 pgs with appendix for calculations -- several graphs,
charts, and pictures.

Willis, Malcolm B.  _Genetics of the Dog_.  417 pgs with breed specific
information on many breeds -- plus several charts and graphs.

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This article is Copyright (c) 1992, 1993 by Cindy Tittle Moore.  It may be
freely distributed in its entirety provided that this copyright notice
is not removed.  It may not be sold for profit nor incorporated in
commercial documents without the author's written permission.  This
article is provided "as is" without express or implied warranty.

Cindy Tittle Moore
Internet: [e-mail]           USmail: PO BOX 4188, Irvine CA 92716
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