|
Eastern NE KS | I believe in your assessment as well. It not one idea against the other but both tools used to improve and move your herd in the desired direction. Indeed, objective measurement of phenotype is the raw data used create the epd value.
In the early '90 I attended my county KLA meeting. Mark Gardiner of Gardiner Angus Ranch was guest speaker. He turned me onto the power of using epds. He showed a graph of herd average weaning weight staying relatively unchanged for over 25 years then start climbing in a significant way. He explained over those early years they used Angus sires from all over the US with top weaning and yearling weight ratios. Yet, the on farm average weaning wt was not changing. Only when they started using ww epd in their sire selection did their on farm AVERAGE weaning wt start moving in the direction they desired.
Weaning weight is an easily measureable phenotype of cattle. When we standardized measuring techniques and apply statical methods to the data, we can compare the WW epds of bulls and make a more predictive assessment of those bulls than from on farm ww ratios.
That meeting did not discuss the ins-and-outs of the epd accuracy. It is that aspect that we further improve the predictable outcome of a mating.
EPDs are a tool beyond visual assessment that allows us to change the phenotype of offspring WITHIN the realm of each particular epd trait. WW epd tells is nothing about animal structure or confirmation. WW epd tells us nothing about udder structure.
At GAR epds unlocked their genetic potential to make focused change. While he talked about WW epd, I'm sure this idea was being applied to the most economically relevant traits at GAR. Herein lies both the power and risks associated with using EPDs | |
|
Terminal vs maternal breeding
