I am going to do a simple comparison
of two bulls. One we recommend; the other tends to be what we still see
competitors recommend. Allow this
to challenge your thinking about bulls.
Example # 1: Lutz Brookview Bevan 6HO1046 aAa 2-4-6-1-3-5 (Tall, Strong, Style)
(1)
Pedigree: five of his six
maternal dams are scored “Excellent”—indicative of cows that are not just
surviving, but thriving in production at mature ages. Cow line depth is supportive of
longevity.
(2)
Conception rate: This
bull is +4.6 SCR. In other
words, if 100 cows are bred, he will get =five more than the average bull
pregnant on that service. (Savings:
$ 6.00 per 10 straws used.)
(3)
Milk check value: This
bull is +.15% on butterfat, +.03% on protein, and 2.75 on
Somatic Cell.
Let us assume you have an “average”
Holstein herd of 100 cows, and sold 20,576 pounds of milk per cow in 2009—at an
average of 3.58% bf and 3.12% protein, with 200,000 SCC.
Current fall milk checks would value
this production at (737 lbs bf at $2.03/lb = $1495.34) plus (642 lbs pr at
$2.38/lb = $1527.89) plus (205 cwt at $1.58 PPD = $323.90) plus (no add or
deduct for SCC).
This totals $3347.13 per cow per year. [and figures out $16.27/ cwt]
If you raise your bf test by .15%,
your pr test by .03%, and lower SCC by .25 on that production level:
(768 lbs bf @ $2.03= $1559.04) plus
(648 lbs pr @ $2.38= $1542.57) plus (205 cwt @ $1.58= $323.90) plus (205 cwt
@.25 SCC @ $0.20= $41.00) This
totals $ 3466.51 [and figures out at $16.85/cwt] which is a gain of $ 119.38 per daughter—even if he has
no impact on lactation pounds of milk!—and is per year of life-- so likely three lactations on average, as we
will calculate below.
(4)
Calving ease: this bull
falls in the average range. His
daughters have 8% difficult births, which is slightly better than average. They have 7.5% stillbirths, which is 1%
better than average. Thus from 100
calvings, he would gain you one extra live calf. Let’s say that is worth on average $2.00
per year.
(5)
Daughter pregnancy rate:
this bull is +0.9 DPR. On
average, his daughters will require one less straw of semen per pregnancy than
average cows, and will calve back one cycle faster than average.
Savings on semen: $12.00 per year. Savings on stale and dry days: (21 x $5.00) = $105.00 per year.
(6)
Productive Life: this bull
is +3.3 PL. On average, his daughters
will produce 3.3 months more milk than the average cow in their lifetime. At 61 pounds per day (20576 lbs / 335 days)
that is 6100 pounds more actual lifetime milk -- at
$16.85/ cwt, that is $1027.85 more
lifetime income.
(7)
Reproductive Life:
implicit in shorter calving intervals (+0.9 DPR) and longer Productive
Life (+3.3 PL) when in combination, means one more calf per daughter lifetime. Add another $200.00.
Add it up: [$ 6 + $119.38 + $2 +$12 +$105] x 3 +
$1027.85 + $200… $1960.99 per
daughter lifetime... all from a $13
straw of semen [net of “buy 10 get 10 free”]…
on a sire who is “only” +84 PTA Milk!
On that basis, his USDA “Net Merit”
of +$376 is, if anything, understating his full use potential.
When (and by whom) were you taught
to select bulls? [perspectives
do change over time]
It is typical in Michigan for dairymen to ask for “plus
milk” bulls—at least +500 PTAM, but some
ask for +1000 or even +2000 PTAM. This
might have made sense years before protein testing, but it is no longer
meaningful as a selection criteria under “multiple component pricing”— which is
why USDA is assigning a “zero” $ value to PTA Milk in calculation of “Net
Merit”. ( Most type conscious breeders
also tend to ignore it, assuming milk volume increases more profitably from
physical ability to mature.)
Example # 2: typical Michigan bull choice: (bred randomly or on linear traits)
0.0 SCR +1500 m -.15% bf
-.10% pr 3.25 SCC 10% dce 9.5% dsb -1.5 DPR +0.0 PL
You are probably asking “What is his type?”
because when you saw +1500m, all the other (negative) trait data went
right out of mind— a +1500m with “plus type” still gets lots of people excited.
But in use, this is what happens:
(1) Pedigree-- the trend in bull books has been to replace
cow line info with sire stacks. But
most of
the dams of generic production sires only show first lactations,
thus no indication of lifetime ability.
(2) Sire conception rate— we are content in expecting three or more
services per conception.
(3) Milk
check value—we expect to see 1500 pounds gain, but due to the ME factors
adding 30 percent to a heifer lactation, we only get 1000 actual pounds. But it is still a gain in yield:
20576 + 1000 = 21576 pounds, at
(-.15%) 3.43% bf and (-.10%) 3.02% pr, with(+.25) 240,000 SCC.
On our milk
check payment formula, this results in 740#bf, 652#pr, 216 cwt, and a loss in
quality.
(704 x $2.03) + (652 x $2.38) + (216 x
$1.58) – (216 x $0.20) = 1429.12 + 1551.76 + 341.28 – 43.20 =
$3278.96 per cow gross income: a loss of ($ 68.17) compared
to what we had achieved before.
(4)
Calving ease: bull was OK, but his daughters are more
difficult than average, which leads to the observation that we lose 1% more
calves than average—a loss of $200 per 100 calves, ($2.00) per dtr.
(4) Daughter
pregnancy rate: this bull is –1.5
DPR which means they have calving intervals extended by 30 days—thus requiring two
additional straws per conception, or a loss of ($24) on
repro and (30 x $5)= ($150) from unprofitable late lactation stale days
or extended dry days.
(5) Productive
Life: this bull is just an
“average” bull—no longevity in his pedigree, no will to live in maturity in his
offspring. They just milk their 2.5
lactations and leave.
(6) Reproductive
life: no gain in calves either—just
one heifer to replace her when she leaves, no gain in accumulated genetic value
from the maternal side.
Add this all up: [ $0 – ($68.17) – ($2) – ($24) – ($150) + 0
+ 0 ] x 2.5 lactations = ($610.43)
generational loss-- as a
result of keeping a too narrow focus on obsolete genetic traits, not taking the
opportunity to gain from other traits of economic importance.
The irony is that a bull like
“Example #2” can be around $250 LNM—again, a problem of indexes being too
simplistic in their estimation of all genetic selection consequences, in this
case overstating the estimated genetic value of a sire who really had
little to offer beyond a faster maturing physique.
Am I pushing “Net Merit?” No— beyond its ability to get us to see
that our income is coming mostly from milk components—where the growth in
dairy consumption and export opportunities lie. As for “Type” I think we all prefer to
avoid the sort of physique that fails earlier in life— but type gives us no further information on
fertility or will to live.
I am suggesting that we need to
take time to see each bull for the total package he offers us.
Give me bulls that will do more good than they do harm
Give me bulls that will do more good than they do harm
The perennial argument among theoretical geneticists
is whether “index” selection is better than “matrix” selection, in translating
genetic change into economic progress.
While current Genomic application indicates “index”
thinking is prevailing, there still remains a question you can ask: is more
economic gain possible than I am harvesting?.
In spite of what you may have learned in a genetics
class five or twenty five years ago, herds do not improve in profitability
unless the individual replacements raised are more physically able to produce
more and cost less to maintain than their individual dams.
“Matrix” selection is a way to tailor genetic
selection to the stage of your herd, allowing a focus on what your herd needs
now—not what your breed thought it needed historically.
Breeding for “lifetime productivity” by considering
all genetic effects can reap gains on milk check price, cost of production, and
culling rate—an optimal use of sire selection.
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