marbling epds versus IMF ultrasounds

[dph]

Kind of related to Mike's original post about marbling, pre Angus debate.

I am hearing more about our breeder and their thoughts on IMF ultrasounding vs marbling epds. Seems that they ultrasounded some of their steers and once killed they found a very poor correlation between their IMF ultrasounds and what ended up on the rail. They used two differnet technicians, both very well versed in ultrasounding. One, used by many breeders, and one out of Iowa State University. The first accurately predicted end marbling 35-40% of the time, the last got it right just under 50%. They have long been skeptical about the IMF ultrasound truly measuring what is later viewed as marbling.

What's anyone else's thoughts about this? Do you use marbling epds or ultrasound info? Have other breeders had similar complaints in other breeds? etc.

They are well known for getting info back on their own steers. And have suggested for awhile that more faith be given to marbling epds, which they feel are more accurate. To my knowledge they have never debated the validity of ribeye and fat ultrasounds. I often wonder about the wide descrepancy between ultrasound IMF and marbling EPDs for many bulls.

Perhaps, with advances in gene testing, this discussion will become academic as we may soon have the introduction of gene based EPDs.

 

[ollie']

I have seen study after study which supported ultrasound. I have sold steers Y and G that were sorted with ultrasound machines and havn't took discounts. I know ultrasound works. Trouble is you also have a feed lot manager , the weather, a trucker, a subjective grading system, etc. I certainly don't beleive that anything I have seen about carcass epd's prove their reliability. If your buddies think ultrasound is bad have them next year sort their steers into a sort to hit y and g premiums and discounts using epd's. :lol:

 

[dph]

I am not positive, and I don't mean to take offense, but I believe these guys were one of just a few ranches whose info the AAA used to create their EPDs. And have possibly contributed more data to the AAA than any other breeder (I know that to be true as of three years ago.) They have been among the leaders in carcass traits in the breed. And again, they do not doubt at all Ribeye and fat ultrasounds. It very well could be some other variable and you are absolutely right, I have no knowledge of how the calves sorted by marbling EPDs would have done. I was only curious whether this complaint had come up before as this topic hasn't been discussed while I have been on the board.

 

[MikeC]

I use Craig Hays from Criticalinsights/Ultrainsights as a technician and discussed this at length when I did ultrasound the Friday before Thanksgiving.

Ribeye Area/Marbling is a fairly "cut and dry" science using ultrasound if all the equipment is calibrated properly and the lab is on the same page as the technician. The software available today for measuring is much more accurate than just a few years ago.

One of the problems Craig sees is that many seedstock producers are ultrasounding bulls only which leaves the cows out of the equation, thereby lengthening the time for accuracies needed in predicting EPD's..

As in any EPD models, the more information put in the system, the higher the accuracy.

Ultrasound those heifers too guys........it'll pay off in the long run!

Animal Science Professor Lisa Kriese-Anderson at Auburn told me a few months ago that DNA markers for carcass merit is only 6% accurate at this time and can only be used in conjunction with ultrasound data for EPD's because of all the unknowns in the biology/DNA process.

 

[dph]

Thanks to both of you for the great info. I appreciate it. I believe that is why this ranch gets info back on every steer they raise, so they have more info for carcass epds. On their own stud bulls on on their cows. I should clarify the orginal post. I think what they found to be inaccurate was how the steers ranked against each other using the IMF ultrasound to predict marbling. Which is quite a bit different as to whether or not they marbled well. And thought their marbling epds better predicted their "rank" Another breeder, who shared their opinion, thought IMF ultrasounding sometimes picked up too many "globs of fat," rather than marbling. ???

This last breeder, Jim O'Neil, echoed the sentiment of your original post, Mike. He thought that most Angus cattle will marble just fine, he was more concerned about the muscling of them, where he felt the breed had some work to do.

As far as DNA markers, the changes are happening rapidly. Bovigen has released a new marbling marker and if calves are homozygous for both genes it is guaranteed that the calves will grade choice. The big problem is the gene they identified doesn't seem to be showing up much in many cattle. They (Bovigen) sound like they are about to release some more DNA markers soon. Sounds like some more for marbling, and feed conversion, and tenderness. It will certainly be interesting to see what happens over the next couple of years. Bovigen is already trying to push the "Verified Tender" program and seems to be getting interest from quite a few breeders. As I understand it, I think Express Angus Ranch owns a good chunk of Bovigen. But I think you hit the nail on the head, Mike. The real promise of the DNA markers is using them to form DNA guided EPDs.

 

[Brandonm2]

I hate to suggest this, but the USDA grader eyeballs the carcass at one cut and makes an educated guess that is the grade. The whole process takes about 5 seconds. Most of those guys are pretty accurate but I think a good ultrasound SHOULD be more accurate than a human grader; but his word is FINAL. I would suspect sloppy grading as much or more than inaccurate ultrasounds.

 

[la4angus]

I hate to suggest this, but the USDA grader eyeballs the carcass at one cut and makes an educated guess that is the grade. The whole process takes about 5 seconds. Most of those guys are pretty accurate but I think a good ultrasound SHOULD be more accurate than a human grader; but his word is FINAL. I would suspect sloppy grading as much or more than inaccurate ultrasounds.

I agree with you Brandonm2. Also you don't know what kind of a night the human USDA grader had the night before either. I knew some of em.

 

[Brandonm2]

I hate to suggest this, but the USDA grader eyeballs the carcass at one cut and makes an educated guess that is the grade. The whole process takes about 5 seconds. Most of those guys are pretty accurate but I think a good ultrasound SHOULD be more accurate than a human grader; but his word is FINAL. I would suspect sloppy grading as much or more than inaccurate ultrasounds.

I agree with you Brandonm2. Also you don't know what kind of a night the human USDA grader had the night before either. I knew some of em.

Yes, back when the old John Morrell plant in Montgomery, AL was still processing fat calves they actually hired their own grader. He graded the carcasses AFTER the USDA grader did and when they disagreed those carcasses were sent to a side rail and the plant grader would plead the case FOR the higher quality grade or lower yield grade.

 

[la4angus]

Does anyone know what the typical ultrasound say for back fat etc. costs? i saw it on rfd tv once?

Hey TCM. What part of Tenn. are you located. I have some partners South of Nashville.