With the recent proof release, breeders now have the opportunity to start seeing the effect of genomics has on the top new proven sire proofs. Thanks to the Canadian System and CDN (Canadian Dairy Network) we can even take one-step further and get a better appreciation of how genomics actually is affecting sire proofs.
In an effort to better understand these effects The Bullvine took a look a closer look at the top 5 new release sires. We looked at their official proofs, DGVs (Direct Genomic Values) and PAs (Parent Average). We also calculated what the sire’s current YS (Young Sire) index would have been (based on the CDN formula of 65% DGV and 35% PA) to see what their current index would have been without daughter information. We then took each of these parts and compared them to each other. The results are as follows.
What stands out in BRAWLER’s official proof is that he actually outperforms his DGV and parent average indexes. While the general expectation has always been that high genomic sires will drop, with the addition of daughter information, BRAWLER is a high genomic sire that actually increased his values. Note that his official values for protein, conformation and LPI significantly exceed his PA values. One of the interesting points on BRAWLER is that his official conformation score is higher than both his DGV and PA values. It appears that so far his daughters are performing much better than his parent average or DGVs predicted, especially in mammary traits.
While BRAWLER’s PA and DGV actually held him back, we see the exact opposite effect for DORCY. NOTE: Due to the need for DGV’s we have had to look at US proven bulls on the CDN system. DORCY posts outstanding DGV values, but so far his daughters are falling short of those values, especially for fat, udders and legs. In fact, his DGV’s actually elevate his proof, by our estimate, by almost 30%. While these early daughters (65) may not be a complete indication of where his proof will end up, current daughter values would predict that we should see declines in these traits.
While BRAWLER’S official proof is higher and DORCY’S is lower than their DGVs, JAY’S official proof is bang on. The biggest difference between his young sire proof and his official proof is that his parent averages are actually much lower than his DGVs and daughter information.
EXPLODE joins his fellow US proven DORCY in finding it hard to live up to his high DGV values. Similar to DORCY, EXPLODE’s daughters are lower than his DGV’s for feet and legs, as well as rump and protein. However, so far his daughters are proving to be much more durable than his DGV did predict over his parent average.
Much like the other Canadian proven sires, BORIS’s DGV values are bang on, with only a slight variation where his daughters are currently outperforming predictions for feet and legs.
When we applied the same analysis to Co-Op Bosside Massey, we see that his daughter information was much higher than both his parent average and DGVs, hence explaining with the addition of more daughters Massey’s proof increasing.
The Bullvine Bottom Line
While most of the early top genomics sires are still awaiting proofs, this analysis of a small group shows some interesting trends. First it shows that there may be differences from country to country in the accuracy of predictions (Editors note: As we have now crunched over 200 US sires we see that this is no longer the case, these two are more an anomaly than the standard. Watch for the results of this number crunching in a future Bullvine post). It also shows that, at least in the Canadian case, the DGV values are a much better indicator of potential than the old PA system predictions. This could be because genomics so far has been able to limit the effects of hot house herds (read Has Genomics Knocked Out Hot House Herds). In looking at the differentials for these five sires, we see that DG Values vary by 6% from official LPI Proofs, while their PA’s vary by 15%. This is in line with CDN’s prediction of a 5% accuracy gain, as a result of using genomics for calculating first crop proven sire proofs. Furthermore, it shows that with daughter information added top genomics sires, can actually outperform their high parent average and DGV predictions.
For more information check out our Genetic Evaluation Resource Center.