I am on the genetics list also and found this post very interesting. The
gentics list is a relatively high traffic list but very informative.Carie
TaylorMoonsong
Chinookschinookrun@...@aocb.commoonsongchinook@...


To: chinookbreeders@yahoogroups.com; ChinookSledDogs@yahoogroups.com;
Chinook_healthnet@...: susan@...: Sat, 29
Dec 2007 21:58:02 -0500Subject: [chinookbreeders] Fw: 21st Century Dog Breeding




The following is FORWARDED (from the Canine-Genetics@yahoogroups.com list) IN
ENTIRETY WITH PERMISSION from the original author.Belated Tullibardine Holiday
Greetings to All Chinookdom from snowy Rossburn, Manitoba, CANADA! Where (34) of
(36) Tullibardine owned beloved Chinooks were legally and successfully imported
finally this past Nov. 1st, 2007! (The two elder females, Perry Greene Natanis &
Bates Argenta, remain in Maine with Mum! :-)Best Regards,Susan E (Murray) Bragg
(aka Mrs. J Jeffrey Bragg)Chinook Trading PostTullibardine Farm
ChinooksCustodian of RecordsInternational Seppala
Associationhttp://www.seppalas.org"Blanket permission to cross-post and/or
forward my 28Dec. 2007 CanGen submission "21st Century DogBreeding" is hereby
granted to list members providedcredit to the author is given and the post
isreproduced in its entirety.J. Jeffrey BraggThe Seppala Siberian Sleddog
Projecthttp://www.seppalasleddogs.comhttp://www.seppalakennels.com--- In
Canine-Genetics@yahoogroups.com, Jeffrey Bragg<ditkoofseppala@...> wrote:Two and
a half years ago I asked on this list whetherwe could not somehow manage to come
up with what Ithen called a "synthesis of praxis" drawn from thetheoretical
principles of population genetics -- a setof guidelines for dog breeders that
would show the wayto a more innocuous mode of dog-breeding than thatwhich is now
practised by the vast majority, a set ofrules, guidelines or principles that
would allow us tobreed in accordance with the principle "primum nonnocere" --
"first, do no harm!" Although a few peopleacknowledged the desirability of such
a document,nobody came up with a draught text and we never reallymanaged to get
a thorough discussion going of whichprinciples ought to be included. That
thread, headed"Dynamic balance + heterozygote superiority vs.screening and
selection"(http://tech.groups.yahoo.com/group/Canine-Genetics/message/17526)term\
inated with a brilliant and thought-provoking postfrom Jim Seltzer (one of the
brilliant minds on thislist whom I hold in great awe and respect), sayingthat I
ought to consider the concept of the "adaptivetopography" sometimes used by
population geneticiststo provide a three-dimensional model of the
dynamicinterrelationship of fitness, gene frequencies andevolutionary
adaptation. I thought about that forquite awhile but never could discover how it
could bemade into a tool for practical dog-breeding. In theend, though, I went
ahead and draughted my own list ofprinciples for 21st-century dog breeding,
which Inever published because I never was able to put itinto a final form that
I thought adequate.Recent discussions on this list have given me an eeriefeeling
of "this is where I came in," notably thoseabout "removing genes," the
impossibility of usingscreening and selection to solve the "genetic
defects"dilemma, the disconnect between geneticists andbreeders -- and the "new
direction" thread generatedby the publication of Koharik Arman's paper. I
foundKoharik's discussion very familiar-sounding. Interminology and concept it
strongly recalled to mindthe dialogue that I attempted without success
toinitiate within the Canadian Kennel Club in themid-1990s with the
self-publication of a briefentitled "Purebred Dog Breeds into the
Twenty-FirstCentury -- Achieving Genetic Health for Our
Dogs,"(http://documents.seppalasleddogs.com/html-documents/pbdb21c.htm),cited as
reference number 3 in Koharik's paper. Atthis point in this list's discussion it
might beuseful for those following it to review the latterbrief published almost
twelve years ago, and then toread Koharik's paper immediately afterward.
Perhapsthe reader may then feel, as I cannot help feeling,that although we may
have raised a certain level ofawareness relative to the purposes of this
list,perhaps we have not really gone anywhere since thedays of Dr. Armstrong's
efforts to raise these matterson the web.Meanwhile the urgent demands of the
Seppala SiberianSleddog Project have required that I "wing it" as bestI could,
creating for purposes of the Project acoherent body of breeding practices. I
have tried tokeep a couple of other developing breeds (such as theShiloh
Shepherd Dog and the Chinook) underobservation, feeling that they shared
similarchallenges to those faced by the SSSD Project; I havenot had the time,
though, to read every post to thislist or seriously to investigate what those in
otherbreeds may have been doing. So, at best, I have had towork mostly from my
own personal knowledge of theprinciples of population genetics, within
theparameters of our own evolving SSSD breed, withrelatively little light shed
on our problems by thepractices of other breeders.Not every breed may be in a
position for its breedersto do some of the things we have done in the
SSSDProject -- breeders of Chinooks, for example, cannotavail themselves of
landrace stock from the "countryof origin" of their breed, both because the
breed issynthetic in origin and because its original componentcanine strains are
not completely known. With thestrong caution, then, that not everything
recommendedhere may be possible or appropriate for all otherbreeds, for every
situation, or for any particularbreed other than the Seppala sleddog, I offer
for thelist's consideration the following guidelines drawnfrom my own imperfect
knowledge and limitedexperience. Please realise that I am not saying thatyou (as
an individual dog breeder) must necessarily doany or all of these things. Still
less would I wish tosee any such guidelines imposed by government as lawsor
regulations upon the dog breeding community. But Isuggest that if you are
concerned about inbreeding,genetic diversity, and inherited illnesses, you
mightwish to consider implementing some of the followingprinciples whose
observance we have found useful inthe Seppala Siberian Sleddog Project.BALANCE
OF SIRES AND DAMS - Make a great effort tomaintain a reasonably equal numerical
balance of siresand dams; don't consistently use fewer individualsires than
dams. The so-called "popular sires"syndrome has received much discussion and
attention.What may not be as well realised is that this selfsamesyndrome is
repeated in miniature in most kennels,where one or two of the "best" males cover
all thebitches, sire all the litters. (How often has oneheard it said that "the
best males should sire all thelitters!") In order to avoid needless reduction of
theeffective breeding population, just as many individualmales as bitches should
contribute to the population;this holds true whether we speak of the
breedpopulation as a whole, or of the population within asingle
kennel.INCESTUOUS MATINGS - Do no incest breeding whatsoever(even if you would
rather call it "linebreeding" orinbreeding). Matings of related individuals
closerthan cousins ought not to be contemplated unless itshould become
absolutely necessary to prevent loss ofa bloodline. This means: (a) no
brother/sistermatings, (b) no father/daughter or mother/son matings,(c) no
half-brother/half-sister matings (i.e., sireand dam share one parent in common),
(d) nograndsire/granddaughter or grandson/granddam matings.This does not mean
that first-cousin matings (sire anddam have different parents but the same
grandparents)are okay or recommended; it is simply a case of havingto draw a
line somewhere, at a given degree ofconsanguinity, in order to say "anything
closer thanthis is quite beyond the pale and cannot even beconsidered."
(Otherwise an excuse will be found evenfor full-sib matings.) If the available
populationdiversity within your own breed allows you to draw theline further
out, so much the better.COEFFICIENT OF INBREEDING - To avoid frank incestmatings
within the first three generations of pedigreeis not enough in and of itself.
The Coefficient OfInbreeding (COI) must also be monitored, preferablyover at
least eight to ten generations of the knownpedigree, keeping it as low as
possible. To do thisover more than two or three generations requires theuse of
computer software such as CompuPed, Breeder'sAssistant, FSpeed, etc. (To
calculate a four to sixgeneration COI only gives a false sense of
security;usually such a COI fails to tell the whole story, andthe ten-generation
COI will be found to bedramatically higher.) In a purebred dog breed COI
canhardly be too low; almost always it is far too high!It is impossible to
recommend an arbitrary figure forpercentage COI, because the situation of each
breed islikely to be different. Probably anything greater than5% constitutes a
distinct threat to genetic health,yet setting the bar at 5% may be virtually
impossiblein many breeds. There are breeds in which breeders mayhave to make
great efforts to get it as low as 20%; inat least a few breeds 20% would be
alarmingly andneedlessly high. But breeders should KNOW what theaverage
10-generation COI level is for their breed, atleast, and seek to keep their own
breeding wellbeneath that average level! Otherwise the COI justgoes on
indefinitely, increasing steadily year byyear. It is easy to point to specific
individuals innumerous breeds with COIs of 70% or more, but it wouldbe a real
challenge to produces examples of less than5% COI in many breeds.One ought to
take care that the COI trend in one's ownbreeding is never upward, but always
either downwardor at worst neutral. This is done by averaging theindividual COIs
of sire and dam (add the sire's COIand the dam's COI and divide by two) and
thencomparing this average with the COI for the trialmating or litter that would
result from mating thosetwo individuals. If the litter COI is higher than
theaverage of the parents, then you are obviouslyincreasing the overall level of
inbreeding byperforming that mating, and the greater the disparitybetween the
two figures, the more the mating should bedeprecated. You may also wish to look
at the same datafrom a different perspective by calculating (with thesame
pedigree software) the Coefficient ofRelationship (RC) when examining trial
matings, themore easily to ascertain which of two or morealternative matings has
the least-related parents.NUMBER OF UNIQUE ANCESTORS - You must use a
breeddatabase in conjunction with a pedigree and COIapplication such as
Breeder's Assistant or FSpeed toexplore COI and trial matings. When you do so,
youshould also use it to study the number of uniqueancestors in the known
pedigree, the number ofancestors in common between sire and dam, and thenumber
of ancestors unique to each parent. Thesefigures are useful in assessing the
potentialdiversity of a projected mating and will tell you morethan the simple
COI (which, after all, is only apercentile probability figure predicting
thelikelihood that alleles at the same gene locuscontributed by the sire and dam
will be identical bydescent).PEDIGREE ANALYSIS - Also try to carry out
in-depthpedigree analysis for every mating, listing the majorancestors on which
inbreeding occurs in that mating,noting the number of occurrences and the
generationnumber of each occurrence. This analysis should becarried back for at
least six ancestral generations,ideally for eight. This practice will alert
thebreeder to undesirable "pile-ups" on key animals andtherefore to potential
genetic problems (if such areknown to be associated with such individuals) in
theplanned mating. An alternative or supplementaryapproach is to use the
"percentage of blood" functionof pedigree software such as Breeder's
Assistant.ASSORTATIVE MATING - Instead of inbreeding, useassortative mating
(mating unrelated parents who arephenotypically similar for the desired traits)
toemphasise or fix greatly desired traits. Assortativemating is much less
dangerous than inbreeding and willaccomplish much the same ends. It should be
obviousthat to breed "like to like" for given desired traitswill tend to yield
more of what is desired, but if theparents are not closely related, there is a
greatlyreduced chance that other unconsidered traits will beunknowingly
reinforced by such matings.GENERATION TIME - Genetic losses occur
almostinfallibly with each generation in purebred dogs,whether those losses
happen through random drift, fromtoo few progeny contributing to the next
generation,from the inbreeding/selection cycle, or whatever. Forthat reason, the
fewer the intervening generationsthat occur between foundation stock and current
stock,the less genetic diversity is lost. Breeders shouldtherefore maintain a
high average generation time (ageof the sire at mating plus the age of the dam
atmating, divided by two) for each litter produced: fouryears should be
considered an appropriate minimumfloor level, five or six is better. It is
helpful tocalculate a running average generation time for yourkennel throughout
its history, by keeping a grandaverage of the average generation times of all
littersproduced.REPEAT BREEDINGS - Do not always use the same sirefor a
particular bitch (or vice-versa). Many kennelsmake a routine practice of
repeating favouritebreedings over and over again. Take care to maintaindiversity
in your matings. Endless repetitions of thesame matings greatly reduce the
available breedingcombinations both within the individual kennel and forthe
breed at large.SIBLING CONTRIBUTION - Try to ensure that at least twoof every
litter (unless it should happen to be one ofthose litters that had best be
forgotten) contributeto the next generation; half the litter should be theideal,
though perhaps a difficult one to maintain. Inevery instance in which only one
progeny from a givenmating contributes to the next generation,automatically and
infallibly 50% of the availablegenetic diversity in that line is permanently
lost! Iftwo progeny contribute the theoretical average loss isreduced to 25%,
still less if more littermatescontribute. This single point is a major source
oflosses of genetic diversity, yet it often goes totallyunconsidered by the
breeder.FITNESS INDICATORS - Monitor key indicators ofsurvival fitness in your
canine stock. These arefertility (percentage of successful matings),fecundity
(average litter size compared to the normfor your breed), birth weights,
nestling viability,survival to adulthood, and longevity; be sure thatyour
breeding programme does not trend toward thereduction of any of these.FOUNDER
BALANCING - It may be valuable to try tobalance the relative contributions of
founders (wherepossible and appropriate), particularly subsequent tofounder
events or genetic bottlenecks. "Founder" is arelative term. If a breed has a
long pedigree historywith original breed foundation stock at thirty or
moregenerations remove from current stock, it may well beimpossible to balance
the contributions of theoriginal breed founders; their relative contributionsmay
already be set in stone for all practicalpurposes. But founder events tend to
occur repeatedlywithin the history of a breed. Bottlenecks occur withdismal
regularity. At least the breeder can payattention to the most recent founder set
that isclearly identifiable, attempt to prevent the loss ofindividual founder
lineages that are seriouslyunder-represented, and seek to balance the
relativecontributions. Clearly this is no simple matter and tosuggest that it be
applied consistently may be acounsel of perfection. At least it is one
morepossible tool in the breeder's armoury againstdiversity losses.OUTCROSS
MATINGS - The great majority of dog breedshave been bred within a completely
closed studbook forsixty to a hundred years, with little or no freshgenetic
input throughout the entire period from breedfoundation to the present.
Similarly, many individualbloodlines have been treated in exactly the same
way,bred in relative genetic isolation from otherbloodlines. Each breeder ought
perhaps to consider thedesirability of locating and using a true outcrosswithin
his or her own breed (unrelated to one's ownstock for at least ten to fifteen
generations) atleast once and to integrate the resulting progeny intoone's
bloodline.If there is any possibility to import unrelated stockfrom a breed's
country of origin, one ought seriouslyto consider doing just that. This is
mainly possiblein the case of landrace breeds, in which anautochthonous regional
population remains in thecountry of origin, independent of exported stock
thatmay have become a registered breed in other countries.Examples of such
situations would be the population ofdesert-bred coursing sighthounds in the
Near East,relative to the Saluki breed in Europe and NorthAmerica, or the relict
populations of autochthonousarctic spitz-type sled dogs relative to the
modernSiberian Husky, Alaskan Malamute, Samoyed, et al.It would be difficult to
overestimate the geneticvalue of a single import animal, unrelated to
the"registered" breed population for scores ofgenerations but stemming from
exactly the samefountainhead. This I would term the "Holy Grail" ofthe diversity
breeder -- the ideal controlled-outcrosssituation in which an immediate
significant increasein healthy genetic diversity may be obtained at littleto no
cost in terms of breed type and purpose. (Thatthe Canadian Kennel Club rejected
this option for theSiberian Husky in 1994 demonstrates, I believe, thetrue
extent to which the umbrella all-breed registriesrepresent an obstacle to
genetic health and true breedimprovement.)In cases of small, highly-inbred
populations for whichthere is no landrace resource, it may become necessaryto
consider an outcross or outcrosses to similarbreeds. If so, this ought to be
faced squarely andproactively by the breed club concerned and breedingsubsequent
to the breed outcross ought to be acollective endeavour, shared for purposes of
morethorough integration and to reduce the work-load onany one breeder --
because, no question about it, theintegration of a breed outcross is a major
task thatcan hardly be undertaken alone by the average breeder.(The Backcross
Project in the Dalmatian breed was anexcellent example of a breed outcross
well-purposedand superbly integrated; but the reaction of the breedclub was
deplorable.)POPULATION GROWTH - In the case of small, developingbreed
populations, it should be regarded as importantto monitor and control the growth
of the population(in number) such that there is steady expansion of
thepopulation within the limits of breeders' kennelcapacity and the demand for
progeny. Growth by fitsand starts, with overexpansion followed by suddencutbacks
or population collapse, is very bad forgenetic health. It is difficult, at best,
wholly toavoid population bottlenecking. But its existence andever-present
possibility should be recognised and towhatever extent may be possible, breed
clubs and theindividual breeders should do whatever they can toensure smooth,
steady population expansion and tominimise cutbacks and consequent
geneticbottlenecking.BALANCED TRAITS - One ought always to evaluatebreeding
stock for balanced characteristics: health,vitality, temperament, working
ability, intelligence,structure, type. Breeders should aim to maintain
thebalanced characteristics of a total dog, not just toproduce winners at dog
shows, field trials, races,etc. An all-round, balanced dog will be a much
betterhope for the future than a highly-selected, over-breddog that is thought
to be "best" due to possessingexaggerated traits in one or two areas, whether it
bea "perfect head," a showy gait, a faster racing speed,or whatever. First, each
individual needs to be a gooddog, and that should come ahead of
breedconsiderations.UNFIT BREEDING STOCK - It ought not even to needsaying --
but in these days in which extensive, heroicand expensive veterinary measures
are routinely usedto save otherwise doomed animals, it does need saying:the
breeder ought never to breed from dogs that wouldnot be alive but for such
interventions (excepting, ofcourse, survivors of physical injuries). It should
beobvious that if we prevent the operation of naturalselection, many of the
animals that we use forbreeding purposes are likely to pass on
varioustransmissible genetic weaknesses.REPRODUCTIVE TECHNOLOGY - Breeders
should alsoconsider whether it is in their breed's interestroutinely to use
elaborate reproductive technology toproduce litters. These days various and
sundrytechnical means are available which circumvent naturalmating and whelping.
Some breeds, indeed, cannoteither mate or whelp a litter without
veterinaryintervention -- already! If we use artificialinsemination and hormone
assay to effect matingcombinations that cannot be brought about by
naturalmating, along with routine C-section to deliverlitters, we may rapidly
find ourselves in the positionof having created strains which cannot
reproducenaturally without technological support. We shouldalso consider whether
it is really a good thing tofreeze the semen of outstanding males and thus
extendtheir breeding life decades into the future; thispractice seems to be
universally approved, while noone appears to have examined what effect
suchextension of the influence of individual stud dogsmight have on breed
genomes.ARTIFICIAL SELECTION - This may really be the mostimportant principle of
all, and the most difficult forthe vast majority to accept. Breeders should
avoid allextremes of artificial selection! When one comes toconsider the problem
of lost genetic diversity,inbreeding by itself is only half the story. The
hardtruth is that selection itself is just as great aculprit, if not worse.
Inbreeding and selectioncombine together in a cyclical fashion in the dogworld
to cause the systematic depletion("depauperisation" to the geneticist) of
purebredgenomes. The desire for a cookie-cutter "consistencyof type" causes
healthy genetic diversity to bediscarded intentionally at an alarming rate.
(Anexample of this desire is the person who declared at aChinook specialty show
that he saw at least fivedifferent types represented there, and that "they
hadbetter get themselves a geneticist or they will neverhave a standard type."
The Chinook is a working breedwith a dangerously low population and a
perilouslynarrow genetic base; the kind of diversity thatengendered that comment
is hardly to be deprecated insuch circumstances.)We hear endless discussion
about inbreeding and itsevils, and rightly so; but we hear very little aboutthe
dangers of sustained extremes of artificialselection, which are if anything yet
more dangerousthan inbreeding. Together these two factors become anengine of
destruction for genetic diversity. Theconstant obsession with having the "best"
dog and with"breeding only the best to the best," whether indog-show terms, in
dogsled racing, or whatever,creates a situation in which the best is
definitelythe enemy of the good. The endless repetition of
theinbreeding/selection cycle in the quest for a dog thatis better than last
year's best, has systematicallystripped away most of the healthy genetic
diversityfrom today's purebred dogs. Stringent, sustainedselection for cosmetic
ideals (shape, number andintensity of the Dalmatian's spots; shape andchiselling
of the poodle's muzzle; subtleties ofcolour and markings in an endless series of
breeds) ornarrow ideals of performance or athleticism (topsprinting speed in
racing greyhounds or racingsleddogs) have for many decades taken
absoluteprecedence over breeding to provide the kind of"genetic outfit" that
will allow the dog to be healthyand hardy.Now that canine diversity has been
stripped to thepoint that homozygous recessive "defect" genes areeverywhere
apparent, the dog fancy proposes to remedythe situation by embarking upon a new
level ofelevated selection, armed with DNA marker testing toenable the wholesale
"elimination" of "defective"genes. This new wave of super-selection on top of
thealready extant depauperisation may well become thekiller wave that will sink
the entire ship of purebreddogdom, AKC, CKC, and The Kennel Club with it.
DNAtesting has become a growth industry. This all may bemore about corporate
profits and grant money, thanabout genetic health. It is up to breeders to have
thecommon sense to realise that what is being proposed isa losing game, that
already depauperate purebred breedgenomes will not support further massive
artificialselection and the consequent wholesale elimination ofyet more genetic
diversity. The "defect" genes cannotbe excised with a scalpel; many other genes
thathappen to reside on the same chromosomes will go rightalong with the
defects, with totally unforeseeableconsequences.In conclusion, let me say that,
although this set ofguidelines cannot be made into hard and fast rules or(worse
yet) regulations -- because the situations ofeach individual dog breed and even
each breeder aredifferent -- yet I believe we all need faithfully toattempt to
apply the principles discussed above, inorder that our dogs may have long,
healthy lives uponthe earth. We should strive to be faithful stewards ofthe
genetic heritage of our canine friends. In thatway we may hope that our
bloodlines will endure longerin the dog world, and in the end we may even
beremembered as pioneer 21st Century dog breeders whostrove heroically to
correct the errors of the past inthe light of better knowledge of population
genetics.J. Jeffrey BraggSeppala Kennels http://www.seppalakennels.comThe
Seppala Siberian Sleddog Projecthttp://www.seppalasleddogs.com--- End forwarded
message ---






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