meta The Hot House Effect on Sire Sampling | The Bullvine

The Hot House Effect on Sire Sampling

Since the Bullvine started in February (and even before), I have had many dedicated breeders ask me ‘Why do the Artificial Insemination companies keep going back to the same herds for young bulls when few if any bulls from those herds ever make it to active proven status?”’ That prompted me to ask – is that true?

Answering the tough questions

For many breeders it can be hard to determine which herds they should use young sires from and which ones they shouldn’t. For many AI companies, and sire analysts they have had their thoughts about which herds are hot and which ones are not, but never had the numbers to prove it. This has us asking has genomics truly eliminated the hothouse effect in sire sampling (read more – Has Genomics Knocked Out Hot House Herds). In true Bullvine style we decided to tackle this tough question to help breeders have confidence in which genomic tested young sires to use. We first took a look at all the herds that had more than one sire receive their first official proof in the August 2012 proof run.

Here is what we found:

HerdCountOfficial GLPIDGV LPIPA LPIGPA LPI
Alta4102210859691043
Claynook39699821018995
Comestar31436136815071418
Gen-I-Beq51658170118001737
Gillette37716921045819
Lorka31239119011811187
Stanton67817371383970
Velthuis31369128017561452

In comparing the columns here is what we found:

HerdCountDGV vs. OfficialPA vs. OfficialGPA Vs. Official
Alta463-5321
Claynook3134926
Comestar3-6871-18
Gen-I-Beq54314279
Gillette3-7927348
Lorka3-49-58-52
Stanton6-43603189
Velthuis3-8838783

(For a complete listing of sires and calculations click here)

In wanting to see if the Aug ’12 results were just a point in time for these herds or if it was truly reflective, we decided to look at all the bulls proven since the introduction of genomics (Aug 2009) from these same eight herds. Here is what we found:

HerdCountOfficial GLPIDGV LPIPA LPIGPA LPI
Alta11929936873913
Claynook14-60-42535166
Comestar357497461030848
Gen-I-Beq221057109211711120
Gillette171337132614421368
Lorka7419396749523
Stanton276646481319889
Velthuis41466142116511504

Again comparing the columns here is what we found:

HerdCountDGV vs. OfficialPA vs. OfficialGPA Vs. Official
Alta117-55-15
Claynook1418595226
Comestar35-328199
Gen-I-Beq223511464
Gillette17-1110530
Lorka7-24330104
Stanton27-16656226
Velthuis4-4518437

(For a complete listing of sires and calculations click here)
 

Let the numbers do the talking

In studying proven bulls we found that most of them fall within the range for difference between the individual bull’s parent averages and official proof of 150-200 LPI points. And for most of the herds hear falling within that same range.

To go deeper and identify which sires are the best sires to sample, and for breeders to use and which sires should not be sampled or used we took a closer look at how DGV’s, Parent Averages and GPA LPI’s compared to their Estimated Daughter Performance*. Here is what we found:

HerdCountEDP*EDP vs. OfficialDGV vs. EDPPA vs. EDPGPA vs. EDP
Alta11926-29-53-13
Claynook14-148-88106683314
Comestar35720-2926309128
Gen-I-Beq221003-5489168117
Gillette1713381-1210429
Lorka7409-10-13340113
Stanton27607-5640712282
Velthuis4149832-771536

*Please note to calculate Estimated Daughter Performance we took each sire’s official proof and back solved considering his DGV and PA using the published CDN formulas and weightings.

These results are consistent with our previous findings that DGV’s are by far the most accurate indicator of which sires you should use/sample. As well, why you should not use sires that have DGV’s below their parent averages (read more – 7 Reasons Why You Shouldn’t Use Genomic Sires With DGV’s Lower Than Their Parent Averages)

The Bullvine Bottom Line

For both breeders and A.I. companies it can be very challenging trying to figure out which genomic tested sires to use and which breeding programs they should consider investing in. As we have found out the numbers tell the whole truth. Genomic results do give us very reliable information. While it may be true that for some of herds it can be said that they breed better female than male bloodlines. Nevertheless, that does not fully explain why A.I. companies have continued to sample bulls from some herds. It also does not justify why sire sampling herds should be asked to take on the risk in their herd improvement programs. As one of my breeder friends often tells me – use the best, cull or ignore the rest.


The Dairy Breeders No BS Guide to Genomics

 

Not sure what all this hype about genomics is all about?

Want to learn what it is and what it means to your breeding program?

Download this free guide.

 

 

 

(T1, D1)

Comments

  1. Thanks for a very interesting article. What I find interesting is the difference between PA and EDP compared to DGV and EDP. If we just had PA for young sires and no genomic data then Stanton looks good 3rd in the list and 300 points behind the top herd, Velthuis. However, with a 700 point drop to the expected daughter performance, they’re now 900 points behind Velthuis. Whereas if we have DGV we see an 800 point difference, which is much closer to the expected 900 point difference.

    The use of genomics should mean that the AI companies look at different herds than they have been used to with only Parent Average data. So, the hot house herd effect should be less effective in getting sires sampled.

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