Mating Strategies
Great genetic influences result from a balance of inbreeding
and outcrossing.
by Jay Leimbach
Republished
with permission from Canadian Thoroughbred
Mankind has been
writing on the art of horse breeding for over three thousand
years, dating back to ancient Greek tablets circa 1500 BC. Even
earlier the Egyptians and Chinese selectively bred for bigger,
stronger horses to pull chariots and wage war.
In modern times agricultural breeders of plant and animal livestock
have carefully chronicled methods of producing better individuals,
from corn and potatoes, to chickens and cattle. The Thoroughbred
industry has kept meticulous pedigree records since the dawn
of the breed some 300 years ago. Unfortunately, many old wives
tales and superstitions crept into the breeding lore, and racing
has never developed a clear strategy for producing top runners.
Other livestock breeders have, and one of the tried and true
strategies has been to find "nicks" between bloodlines
showing strong affinities for one another. In the words of author
M.E. Emsinger: "If the offspring of certain matings are
especially outstanding and in general better than their parents,
breeders are prone to say that the animals nicked well. For example,
a cow may produce outstanding calves to the service of a certain
bull; but when mated to another bull of apparent equal merit
as a sire, the offspring may be disappointing. Also at times
the mating of a rather average bull to an equally average cow
will result in the production of a most outstanding individual...
"So-called successful nicking is due, genetically speaking,
to the fact that the right combination of genes for good characteristics
are contributed by each parent, although each of the parents
itself may be lacking in certain genes necessary for excellence.
In other words, the animals nicked well because their respective
combinations of good genes were such as to complement each other."
Two great students of breeding from the early 20th Century were
Frederico Tesio and J.J. Vuillier. Tesio bred undefeated European
champions Nearco and Ribot, while Vuillier created the original
Dosage Theory. Tesio listed inbreeding, nicks, and selection
for quality as the three factors which produce speed in the racehorse.
Similarly, Vuillier considered 1) Dosages 2) Inbreeding 3) Nicks
4) Racing Aptitude and 5) Conformation, in order of importance.
A good mating might be compared to a recipe for a good meal.
Sometimes the very finest foods may not combine well, like steak
and caviar, while modest ingredients like peanut butter and jelly
can combine sensationally.
The goal of livestock breeding is basically to ingrain the most
desirable traits of a breed, while improving less desirable ones.
This has usually been accomplished by a combination of inbreeding
and outcrossing - returning the best blood present in a stallion
or mare's pedigree, while adding the best bloodlines missing.
Too much inbreeding will often fix some negative traits, while
too much outcrossing tends to un-fix the very traits we are selecting
for. A balance between the two is usually ideal.
The Thoroughbred has reached a point in its evolution where crosses
of 4x4 and 4x5 are generally ideal. Seattle is inbred 4x4 to
Nasrullah, Mr. Prospector is 4x5 to Teddy, and Northern Dancer
is 4x5 to Gainsborough, for example. (Note that Nasrullah, Teddy,
and Gainsborough were all great influences genetically.) Triple
Crown winners Affirmed (5x5x6x7x6-Teddy), and Citation (5x6x5x4-St.
Simon) were more distantly linebred to great genetic influences.
Outcrossing introduces many variables but can create great hybrid
specimens under the right circumstances. Secretariat and Mill
Reef were both outcrossed 5x6. Both were products of the golden
cross between the Nasrullah and Princequillo lines. Outcrossing
between less compatible bloodlines is unreliable and tends to
create too much variation in the offspring.
Mr.Prospector, Northern Dancer, and Nasrullah are now the three
dominant bloodlines in the sport. In general we should look to
add their blood to a mare who lacks them, and inbreed or linebred
to them when feasible.
Suggestions for Canadian sires this season
I have examined a handful of stallions standing in various regions
of Canada in 2001 to find bloodlines that figure to cross best.
This will only be an educated guess until these stallions prove
over time what bloodlines they prefer. Bear in mind that each
mare is an individual and may not typify her bloodlines in terms
of size, conformation, or running aptitude.
Talkin Man is a son of With Approval and was two-year-old champion
in Canada in 1994. From the Nasrullah male line, he is also inbred
3x4 to Buckpasser. His sire has done well with Northern Dancer/Vice
Regent/Deputy Minister blood, which figures to help Talkin Man
as well. Mares with strong Princequillo blood should enjoy his
Nasrullah blood, while mares with Mr.Prospector blood should
appreciate his 3x4 dose of Buckpasser.
Bold n' Flashy is a son of leading sire Bold Ruckus, also from
the Nasrullah line. Already successful at stud in Ontario, Bold
n' Flashy is linebred 4x5 to Nasrullah and 4x5x4 to Polynesianùthe
sire of Native Dancer. His sire has crossed very well with Ribot/Graustark
blood, as well as Round Table/Princequillo blood.
Whiskey Wisdom is a son of Wild Again, from the Icecapade line.
Mares with Nasrullah blood through Bold Ruckus and Seattle Slew
appear ideal, as does Northern Dancer/Vice Regent blood. Mares
with the bloodlines of Buckpasser, Ribot, and Turn-to are also
promising matches.
Highland Ruckus is another son of Bold Ruckus off to a good start
at stud. His sire crossed well with Ribot and Princequillo blood.
The blood of Vice Regent/Deputy Minister is a natural, as are
mares with Mr.Prospector/Raise A Native blood.
Devonwood is by Mr.Prospector's fine son Woodman. This bloodline
particularly loves crosses with Nijinsky II (by Northern Dancer),
as well as the blood of Riverman and Seattle Slew from the Nasrullah
line. Inbreeding to Native Dancer and Buckpasser are strong possibilities.
Regal Remark, like Deputy Minister, is a son of champion sire
Vice Regent. His dam is by Speak John, from the Princequillo
line, and inbreeding or linebreeding to Princequillo should reinforce
this very compatible bloodline. Nasrullah blood, perhaps through
Bold Ruckus mares, also looks promising. The blood of In Reality
and Turn-to has crossed very well with this line as well.
Castle Arms is by Mr.Prospector's rising son Carson City. Mares
with In Reality and Buckpasser blood have flourished with the
Prospector line in general. Because Carson City is inbred 4x4
to Nasrullah, it seems likely that Princequillo blood, through
the likes of Round Table, Prince John, Speak John, and Stage
Door Johnny should thrive. Inbreeding and linebreeding to Northern
Dancer, Nasrullah, and Native Dancer appears promising.
Cossack Fighter is a son of Siberian Express from the Caro branch
of the Nasrullah line. Not surprisingly, the blood of Northern
Dancer and Mr. Prospector has crossed very well with this line,
as has deep linebreeding to Nasrullah. The blood of Apalachee
from the Princequillo line reinforces a great nick.
Crown Attorney is by Deputy Minister's son Silver Deputy. Silver
Deputy has crossed particularly well with Ribot blood, (through
Tom Rolfe and Graustark), and Bold Ruler blood. Crown Attorney's
dam is a granddaughter of Bold Ruler, thus inbreeding to Bold
Ruler, (perhaps through Bold Ruckus mares), should have potential.
His sire, Silver Deputy, has already shown an affinity for Bold
Ruckus mares.
Regal Discovery by Regal Classic, won the '95 Queen's Plate and
is a grandson of champion sire Vice Regent. Regal Classic has
shown a strong affinity for mares with Raise A Native blood,
such as Mr.Prospector and Alydar. Linebreeding to Nasrullah or
Ribot offer other strong possiblities.
Deputy Bodman is a son of the great champion Deputy Minister,
who led the North American general sires list in both 1997 and
1998. Deputy Minister has excelled with the blood of Turn-to,
Princequillo, Buckpasser, Alydar, and Nasrullah (through Secretariat
and Blushing Groom), and mares with these bloodlines should complement
Deputy Bodman particularly well.
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Other livestock breeders have
found, one of the tried and true strategies, has been to find
"nicks" between bloodlines showing strong affinities
for one another.
The goal of livestock breeding is basically to ingrain the most
desirable traits of a breed, while improving less desirable ones.
This has usually been accomplished by a combination of inbreeding
and outcrossing - returning the best blood present in a stallion
or mare's pedigree, while adding the best bloodlines missing.
Tesio listed inbreeding, nicks, and selection for quality as
the three factors which produce speed in the racehorse.
The Thoroughbred has reached a point in its evolution where crosses
of 4x4 and 4x5 are generally ideal.
Mr.Prospector, Northern Dancer, and Nasrullah are now the three
dominant bloodlines in the sport.In general we should look to
add their blood to a mare who lacks them, and inbreed or linebred
to them when feasible. |
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