DNA vs Performance

[jscunn]

The would you buy this bull got my mind turning.. Which do you trust more your eye or the DNA test. This is a real world example, flush brothers, run in the same group of et calves, sold in the same sale for the same money ($50 difference).. I dont know that there is a correct answer.



Bull A
DNA Percentages
CED BW WW YW DMI YH SC Doc HP CEM Milk MW MH
20 24 12 11 31 13 27 5 52 44 1 1 1

CW Marb RE FAT Tend
5 3 8 2 92
Performance
Adj BW 78 Ratio 93
Adj WW 752 Ratio 100
Weaning Frame Score 5.7
Sale Day Wt 1030
ADG 3.59
Projected YW 1326
Frame Score 5.6

Bull B
DNA
CED BW WW YW DMI YH SC Doc HP CEM Milk MW MH
15 19 38 20 51 47 33 18 33 32 5 19 26

CW Marb RE FAT Tend
46 10 16 11 88

Performance
Adj BW 90 ratio 107
Adj WW 759 Ratio 101
Weaning Frame Score 5.8
Sale Day Wt 1195
ADG 4.58
Projected YW 1491
Frame 5.9

Without printing the EPDs Bulls A are better, I thought the B bull was the much better bull in person, but the A bull was the much better bull on paper.. So what would you do?

 

[WalnutCrest]

Me? Probably neither. Their daughters would be way (!) too expensive to maintain. I'm more a fan of shorter, dumpier cattle.

Between the two, Bull B is probably a faster maturing bull. Do you have SC on either / both?

How were they developed?

 

[fhug]

Depends on what you are breeding them to. If you are breeding to cows to sell pounds, I am pick B. Shows more growth potential.

 

[jscunn]

A was 38 cm
B was 36 cm

Wouldnt A be the earlier maturing bull, he was smaller framed (ie slowing down), but the B bull was showing more of a neck crest in person..

 

[Red Bull Breeder]

I think the dna is much better at predicting carcass traits than any thing else. I will take what my eyes tell me over what a piece of paper tells me

 

[jscunn]

I agree about the DNA being a good predictor of carcass traits. The A bull should have scanned better than the B bull, but I dont have that information only one was scanned. I would have guessed both bulls would have above average scan data in there contemporary group.

 

[WalnutCrest]

A was 38 cm
B was 36 cm

Wouldnt A be the earlier maturing bull, he was smaller framed (ie slowing down), but the B bull was showing more of a neck crest in person..

... slowing down = getting to the finish line of sexual maturity faster ... can't get a bred heifer until she cycles ...

A thought experiment ...

If you put both bulls into separate groups of 200 open, healthy, fertile females and left them in for 60 days, which bull do you think would give more calves?

 

[dbird33]

I'm still a DNA skeptic to some degree. I just don't think it's completely dialed in yet. There are millions if not billions of combinations of genes that may impact a specific trait in ways that haven't been identified. If dna was infallible they would give .90+ Accuracy on tested animals. I know a couple guys that sell bulls and they won't dna them because they are afraid they'll get torpedoed. Pretty sure that's why SAV America hasn't been genomically tested.

 

[jscunn]

My guess would be the one showing signs of sexual maturity.. (ie neck crest). But with bulls that young who knows..

 

[jscunn]

I am a sceptic as well. I do think the carcass DNA is pretty good. The production DNA is wrong more than it is right. Had a female couple of years ago that we DNA tested with a group of heifers. Biggest yw we ever had from a heifer, she was 80 lbs bigger than anything else. DNA said 86 on yw. She dropped from 110 to 89 on YW epd.. recalibration moved her DNA to 58 and moved her yw to 91. Best 3 yr old we have..

 

[Red Bull Breeder]

I have saw the same thing with some my cows Js. Half sisters the dna shows one to have better milk and growth than the other. She has never weaned a bigger calf than the one with lower milk and lower growth.

 

[Jeanne - Simme Valley]

I'll still go by my eyeballs and hard data (scale weights - measurements).