Saturday, May 6, 2017

Are we really making “genetic progress” ?

From the Jan Feb 2015 Dairy Route Letter

Of course we are—that is what the data says, and figures never lie.

We have to remind ourselves constantly in the business of breeding that “genetic” means “population” NOT  biological function or relative transmitting ability or even realized performance.    Genetics only measures the “current” measured generation, it does not compare the “new” against the “old” on either an individual animal basis or a philosophy of selection basis.

What do I mean?     Geneticists cannot tell you if “Mogul” today is superior to “Elevation” in his day.     You actually need a supply of Elevation semen to use at the same time on the same mates as Mogul to answer that question.     They prefer to assume that, because today’s herd averages are higher than in the 1970s, at least for yield traits, Mogul must be superior to Elevation.    

And as much as “breeders” will generally object to the idea that these newer, genomically identified “supersires” are “genetically” better (Genomic definition: possess a higher percentage of the desired “marker”genes associated with measured traits) –  geneticists, not breeders, control the agenda of selection for future AI sires, and are not concerned with prior industry definitions of “greatness”.

Thus, a sire like Rosafe Citation R *RC whose entire list of classified daughters averages an actual 84.0 points, but virtually all scored between 1962 and 1990, can be imputed as “minus” for type against the current type “headliners” whose actual score average may be less than 80.0 points.     The physical type considered superior in that era, while having transmitting influence behind today’s cattle, is different in many traits and can produce a different resulting score under current linear assumptions.

Likewise, while a higher percentage of tested “Citation R” daughters exceeded 100,000# and 200,000# lifetime production (before rBST or TMR) than any leading sire of the modern era, their annual lactation averages followed the classical pattern to maturity, doing their best efforts at ages cows no longer reach.
The relevant question is not being asked       

What is the goal of your breeding program?     If it is simply to have the highest indexing herd (without necessarily producing competitive animals in the high pressure Genomic market) just use the newest of the new, and buy them off the top of the list—the same way most AI salesmen tell you.     If you have a constantly updated physical and nutritional environment for your dairy, you will gain production.

My only question for you then, is “can you afford to constantly update your facilities, equipment and feeding to harvest all this accelerated genetic potential” if the only payback is a 382 pound gain over a five year period??      [How much equipment can you buy on the marginal profit from 76 pounds of milk per cow per year?]    

This is the ultimate fact of the numbers—55% of all semen sold is selected on the above premise, with data promising up to 2500 pound gains on individual sires—yet we are not harvesting a fraction of that.
Even if you argue but we were focusing Net Merit on health traits and longevity, not milk yield, why did Holsteins only gain one month (on an already short 29 month herdlife) over the same five years?

Genetic potential is only half of what it takes.   The other half is matings to produce sound physiques.

Most dairymen are going to use facilities already built for the remainder of their dairy career.    Each facility design was in part based on a given target production and requires a certain margin over feed and all other costs to generate the profitability needed to maintain desired household incomes.   If we try to push production above the level expected from the design, cows will die at earlier ages.    Margins fall on the incremental milk produced.   Profitability declines over time no matter how high the production.

Cows differ in their cost of production.    One of the long held assumptions of geneticists is that the cow who milks more has lower feed costs—as if every cow eats the same feed volume.    However, this idea never made sense even when we did stick cows in stanchions and give them all one coffee can of grain.  
As soon as we started “challenge feeding” cows, some of them went up in yield.    Because we did not measure anything else, we based evaluation on the assumption this was the core of “genetic value”.

Dairy profitability is based on controlling costs of production, not total yield.    This is because profit per unit in commodity production goes to the “least cost” producer, not the “biggest volume” producer.   
There are few economies in scale in animal housing, care and milking—only on the equipment side.   As a result, the best breeding program combines multi trait gene selection with physique-based mating to produce cows capable of competitive, high value per unit production at a minimal involuntary cost to sustain production.      This is the goal of our sire selection and mating guide.

Mich Livestock Service, Inc ** for the Best in Bulls ** independent in breeding ideas since 1952
Greg Palen and Associates                       ph (800) 359-1693      

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