Increasingly,
I hear from dairymen that the AI industry no longer provides all the
information they are seeking in order to select the sires they intend to use. We are being asked to “trust the Genomic
ranking” without any supporting pedigree or performance data (most active AI sires too young to have
milking daughters).
How “reliable” is Genomic trait data as used in the ranking indexes?
For Holstein
sires assume 70% Rel on Production traits, 60% Rel on Type traits, 50% Rel
on the various “fitness” (health and fertility) traits. This is a composite of each
category; in the case of individual linear trait measures, the Reliability
could in fact be much lower.
Can
Genomic values be compared “face value” with Progeny Evaluated Sire values?
All the sire
values presented on various “ranking” lists do so – but it may not be truly
accurate to be presenting them as the AI industry currently does, for the
simple fact that until any bull has milking daughters evaluated, all
“values” published are simply estimates. A
Genomic “value” as published is based 40% on “parent average” (pedigree) and
60% on “gene marker possession” (values imputed to their DNA from association
with genes seen in the “reference population” of historical 99% Rel. progeny
evaluated sires). This has a tendency
to inflate the values above the attained range of “proven” (progeny evaluated)
sires, for those youngsters who possess
the most desired gene markers.
How
often do “Genomic giants” live up to their expectations?
Just as we saw
with the “Elite Sampler” and “Genetic Venture” sires of the pre-Genomic era,
the most variation between “G Value” and “Progeny Verified” occurs
at the extremes. It is the Genomic
sires in the 80th percentile (often a generation older than the
elite 99th percentile, due to having dams who have actually calved
and can be evaluated on actual performance) who are the most stable sires,
comparing their G-DNA to the progeny data that follows.
How we perceive the sire programs we offer
You will note that (a) every AI stud we represent continues to print sire directories with photos of the bull, his dam(s) and his offspring. The maternal pedigree detail is provided—not just a “sire stack”. In contrast to the mainstream of AI sire selection, all these programs focus on, or at least pay equal attention to, the cow lines behind their bulls—we all milk cows, NOT bulls so knowing about the quality of cows behind these bulls adds significantly to Genomic estimates.
More “aAa” variety across our total program also offers you hybrid vigor “outcross” potential!
Reading the typical
Sire Data Block as we present you
today
Refer to the enclosed flyer featuring 566HO1281 Melarry DARK
HORSE -ET
International Protein Sires selects
new sires on a combination of Genomic estimates, a sound conformation, and well-developed maternal pedigree lines. {see area #1 marked}.
The photos of his first milking daughters tell their own story. To the right of that photo you see a
graph of linear type traits according to Holstein USA
official classification. {area
#4} Bars to the right suggest above
average trait expression; bars to the
left below average.
looking at {area #2} below the daughter group photo:
HFA: registration number 100% RHA-NA means his entire ancestry can be
verified by HFA
*TC *TY *TV *TL *TD he has been tested and found “free” of five major lethal recessive genes
Born: birth date aAa: his mating physique DMS: an alternative mating guide
[A1A2] Verified by DNA tests, his gene possession that affect production of
“Beta Casein”s.
Looking at {area #3} begins with CDCB (Council on Dairy Cattle Breeding) = calculates the genetic evaluations as PTAs (= Predicted Transmitting Ability) as of 4/21 (date of summary)
GTPI 2499 “Genomic Total Performance Index”
as formulated by Holstein USA
+1032M (lactation deviation for
Milk yield) +.00% +41F (deviations for butterfat % and yield)
+.01% +34P (deviations for protein
% and yield) 94%
Rel. (statistical
“Reliability” of data)
Type +1.98 (total type score deviation) 87%
Rel. (statistical “Reliability”
of type data)
UDC +2.50 (“udder trait composite”)
FLC +0.67 (“foot and leg trait composite”) These are calculations combining the linear
traits from {area #4 above} to create “ranking” indexes.
NM $341 (USDA “Lifetime Net Merit”
ranking) for conventional dairy
systems
CM $347 (USDA “Cheese Yield Merit”
ranking) for markets that pay on
cheese yields
GM $303 (USDA “Grazing Merit” ranking) estimating adaptability to grazing systems
FE 128 (relative “feed efficiency”) FSAV
111 (relative “feed savings” ) latest research
EFI 9.3% (level of “expected future inbreeding” compares pedigree to bulls in
greatest use)
135 Dtrs/ 47 herds (number of progeny in number of herds
affecting the rankings given)
Wellness Traits: As
calculated by “Zoetis” Genetics division of Pfizer Pharmaceuticals: for--
MAST (mastitis) LAME (lameness) MET (metritis) RP (retained placenta) KET (ketosis) DA (displaced abomasum)
where “100” is average, higher number is better. DWP$ 310 is an adjusted “Net Merit” value once WT -$12 (weighted Wellness
Traits) is factored in.
Milking Speed: 100 (=average) Milking Temperament: 103 (=better than average)
Calving Ease / OBS / Dtr CE: 2.5% (direct calving ease) 410 (# observed) 2.9% (his daughters)
Actual Daughter Average score: 80.3 (average 77.0) AASC 83.6 (Age adjusted score)
Actual Daughter Avg. Production: expressed on a “mature Equivalent” basis, yields and %s
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