Sunday, June 14, 2015

A Tale of Two Emerging “Exceptional” Sires

From the July August 2012 Diary Newsletter

The mainstream of dairy genetics has been enthralled with Genomics since the first release of G tested “super samplers” four years ago.    40% of  Holstein/ Jersey/ Brown Swiss semen sold is now from G tested sires that do not yet have progeny evaluations.    Taurus Service and its foresighted President Richard Witter were in the vanguard of the seven major AI studs that supported research into Genomic applications for dairy, alongside six purebred breed associations and the AIPL geneticists at USDA.

In Genomics, we look at fractions of the DNA for the “marker” genes associated with the genotypes of historical high performance sires.    PTA values are “imputed” from the gene possession of current sires compared to this historical database.    Rel% of Genomic data is almost double that of Parent Averages.

In this time there have been some spectacular failures (Shampoo, Mitey P, Spearmint) but each summary at least one sire will live up spectacularly to the Genomic expectations, keeping AI sire analysts excited by the potential of this tool to save them time locating sires who will “rank” in future summaries.

One more daughter and he would be the #1 bull on Holstein USA’s TPI ranking

76HO 581   Wabash-Way  EXPLODE –ET   (VG 88)        aAa:  2 3 4 1 6 5    “Tall + Open + Strong”

“Explode” generated enough excitement on his pedigree-exceeding Genomic values that he was used as a “sire of sons” as soon as semen was available.    He has sons in AI and daughters being ET flushed for AI, all based upon Genomic imputations.   Now with his first milking progeny, he looks like this:

+2265  GTPI    +1703m  -03%  +54bf  -01%  +49pr   2.75 SCS   -0.6 DPR   +3.5 PL   $548 Net Merit
8% calving ease   (6% daughter calving ease)   +3.74 PTA Type   +3.08 Udders   +3.02 Feet & Legs

What sort of pedigree generates this level of Genomic success?

“Explode” is a son of Sandy-Valley Bolton who was #1 TPI sire at time of his birth.  His dam Wabash-Way Emilyann (VG 88) (Dam of Merit) is a daughter of previous #1 TPI sire, Picston Shottle.   Emily Ann is the eleventh (11th) generation of VG or EX cows with calculated indexes, from the cow line of Whittier Farms Lead Mae  (EX-95), an early “Leadman” from a “Blackstar”.

The “sire stack” explains how you add up high indexes:  Bolton x Shottle x O-Man x Mtoto x Rudolph x Leadman x Blackstar:  all were #1 for Net Merit, TPI, LPI (Canada), BW (UK) or Inet (Italy).   Such are the sires on which the Genomic database is based and the imputation of value is calibrated.

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