“A breeding tool I have found useful is aAa. I would encourage all of you to consider how this could help you to breed better cattle for your operation.”
John Mark Weaver, Fredericksburg Ohio
Panel discussion 2020 Ohio Winter Grazing Conf.
Thank you,
John Mark, for this endorsement. If you
do not know him already, he is breeding purebred registered Holsteins, and is
an accomplished grass dairyman.
His success grazing pedigree Holsteins has astounded many, but so has Amos Nolt
(the first “no grain” grass dairyman with whom I have worked, also a supporter
of using “aAa”) with his polled Red Holstein breeding focus.
The general thought among graziers, influenced by advice from New Zealand and University experts, has been “if you are going to graze, get rid of your Holsteins.” Various advisors (and commercial AI marketers) have promoted crossbreeding or smaller cow breeds or New Zealand and Australian genetic sources, all with the idea their choice is essential to grazing success. And—initially (two or three cow generations) – the advice of all these “experts” has worked for most who tried it.
The problem with all advice (including mine??!!) is that it has been influenced in some way, either by a short-term PhD. research designed to support a foregone conclusion, or by an opinion that what you are already doing has anything wrong with it. The grazing industry is recognizing that mainstream genetic evaluation is focused on the economic results for high-input, TMR, confinement dairy (and draws the majority of its data from those environments). Thus it is seeking its own way, making the grass-dairy industry subject to confusion over breeding.
Everything can be made to look logical and useful when we are collectively unsure of the basis of mating and genetic selection in cattle to begin with…
What is the Truth? “facts” tend to be limited by time. They are “true” at the time they appeared evident. (example: “hybrid vigor from crossbreeding gives 7% more milk, better fertility, more health, than straight breeding.”) They work for one, maybe two, possibly three generations—then no longer work. In some cases, the solution promoted to fix one issue just starts to create a new problem than becomes evident (again, in that third generation, when every “one size fits all” solution starts to cause “inbreeding depression”).
The biggest problem even with “research-driven” conclusions is that we do not see a need for “research” until we have already bred a herd (or a breed) into that problem. We saw this fifteen years ago in the Jersey world, where comparative breed statistics showed Jerseys as #1 for health, fertility, and Productive Life -- but by pedigree, were the most “inbred” of all major dairy breeds and thus feared “inbreeding depression” {more puzzling, the breed with the lowest inbreeding coefficient at that same time was the breed with the worst health, fertility and Productive Life statistics!}. However, the Universities paid to do this research (all of whom had Jersey herds) could document “inbreeding depression” at high levels in their herds, in spite of their use of the “best” bulls in the recommended way. Their conclusion? We must create some new outcross bloodlines, after years of recommending no Jersey breeder should use Danish, Canadian, any show type or local private-owner (eg, Ohio Northcoast polled) bulls, or “aAa” mating.
Once the research concluded that the Jersey breed was actually less “inbred” than in a period of time before index ranking of sires, but had better health, fertility and longevity data in that era of linebreeding and on-farm herdsires, the entire discussion was dropped. But do problems go away if we no longer choose to pay attention to them? This is the mental state of dairy genetics and breeding, and the context in which breeding theories and fads arise and thrive.
As a student of breeding history, I adhere to the mantra of all historians, “Those who deny or ignore history are doomed to repeat it.” Thus my goal is to offer you a useful tool, that has helped dairymen all through the history of AI, and is applicable to every style of cow management, with a simple premise: Breed a cow to be adaptable to any environment, and she will succeed in spite of change to that environment. Then make it continue to work in multiple generations.
No comments:
Post a Comment