REA Size

[Boot Jack Bulls]

For those of you that breed and/or use registered stock, what do you consider an acceptable size on an yearling's actual ribeye area? Do you have different ranges based on breed or if the end goal is more maternal or terminal? We just scanned our yearlings early last week, so it got me to thinking this would be a good topic for discussion. :?:

 

[frieghttrain]

We AI to reg Angus don't really look at the ribeye. Joe

 

[Son of Butch]

Accuracy on carcass traits are so low before a sire is 8-10 yrs old that when it comes to sire selection I end up looking at $ indexes more than individual carcass traits. I look at REA but it hasn't been a strong influence on final decision.
In example War Party a heavily used A.I. sire turns 9 this year. bw acc .95 but rea acc .64
7an380 Endurance just turned 4 in February and already......... bw acc .75 but rea acc .38
personally i figure .70 acc or higher to consider a sire proven

 

[Boot Jack Bulls]

Accuracy on carcass traits are so low before a sire is 7-10 yrs old that when it comes to sire selection I end up looking at $ indexes more than individual carcass traits. I look at REA but it hasn't been a strong influence on final decision.
In example War Party a heavily used A.I. sire turns 9 this year. bw acc .95 but rea acc .64
7an380 Endurance just turned 4 in February and already......... bw acc .75 but rea acc .38
personally i figure .70 acc or higher to consider a sire proven

I understand what you are saying on accuracy Butch. I'm thinking maybe there just aren't many people who utilize ultra sound scanning outside of the bigger breeders in each breed???? Is the actual REA and other carcass data of a herdsire prospect just not something most people take into consideration???? This is something we run in to with the Boer goats as well. My moms herd is one of the only ones in the country to scan goats for carcass data. The associations don't even have a way to utilize the data, so you simply can't consider it when purchasing most herd bucks. I know several beef breeders in our area, both large and small, that scan all their yearlings, so is it just not common practice?

 

[Supa Dexta]

Local bull test station will measure it, and even announce the higher end bulls for it during the auction but I doubt more than a small percentage of buyers pay attention to it. Heck half of them are doing a crash course in the stands on whats epds even are.

 

[wbvs58]

You are talking about raw data figures of the actual scan?? I don't think you can look at this actual figure and say what is good because Breedplan data is only relative to the figures of the actual group of cattle. It does not consider the actual scan figure but is interested only in an animals ranking amongst his peers so you need a group of cattle all the same age and sex kept under the same conditions to get the relevance. The data is then processed and the pedigree is considered to link between different herds.
The raw scan figure will vary widely with the age and condition of the animal. I have only had limited numbers scanned at bull sales on 2yr old bulls and like to see over 120sq cm with the occaisional one around 130sq cm but then these are very well fed 2yr olds.
Ken

 

[Son of Butch]

REA is .38 heritable and breed average REA is .42
top 25% .62 bottom 25% .22 for a total difference of .40
How economic viable is a .20 REA difference (to move from average to top 25%)
or to move from bottom 25% to breed average when heritable is .38 and accuracy of data is about 50% reliable?

I believe it's mostly large breeders that bother with the extra expense and labor to utilize ultra sound scanning and
1/2 the reason is more for marketing of breeding stock than for economic herd improvement.
Until packers demand it by paying more for larger REA, I believe it will remain a lower priority for most ranchers.

 

[Son of Butch]

Local bull test station will measure it, and even announce the higher end bulls for it during the auction but I doubt more than a small percentage of buyers pay attention to it. Heck half of them are doing a crash course in the stands on whats epds even are.

:nod:

 

[Boot Jack Bulls]

Thanks for the insight Butch. I guess I'm so used to seeing the data in sale information and using the scan data, I took for granted that people were doing the same. I understand that it may not be a highly heritable trait, but especially for a commercial cattleman who buys a registered bull and sells the calves as terminal, wouldn't it be useful information? Sorta stacking the deck in your favor????

 

[Air gator]

I found this link from the Angus Association. https://www.angus.org/Nce/Carcass.aspx
I hope it will help you. Gardiner Angus does more research on carcass traits than any other organization.
They have a lot of videos on Youtube. I think I heard that you have to have 7 calves scanned to get .47 accuracy.
Gardiner really dominates on marbling and carcass traits and rely on genetic testing and data more than any other breeder. There seems to be a great divide in the Angus breed...the Gardiners and others who believe that it's all about carcass and other breeders who say that they get paid by the pound. The latter also use the argument "If the cattle can't walk what good is marbling?" I think there has to be a balance...but nearly every beef bull catalog has a report on marbling and carcass traits and how important they are.

 

[Boot Jack Bulls]

Air Gator, I familiar with carcass traits and how to select utilizing them. The Limi breed has been big into scanning for quite a while now, so much so that it is hard to move a young Limi bull to another Limi breeder if he hasn't been scanned. As I said, we scan our yearlings as a rule, and have my own parameters for what I think is an acceptable REA in a yearling. I am curious as to what others think is acceptable in their programs, whether it is to help decide which boys get cut, or which sire to use. I was just interested in how this differs from program to program. TIA.

 

[Son of Butch]

Thanks for the insight Butch. I guess I'm so used to seeing the data in sale information and using the scan data, I took for granted that people were doing the same. I understand that it may not be a highly heritable trait, but especially for a commercial cattleman who buys a registered bull and sells the calves as terminal, wouldn't it be useful information? Sorta stacking the deck in your favor????

I agree it's useful information and I do look at it, but coming from the commercial side $ index is used more often
and $F pushes my hot button even more than $B and REA less than either. $W also sways me more than ww.
Registered breeders may view things much differently than me and probably should and do use individual traits more.

 

[jscunn]

BootJack,

In a perfect world I like bulls to have a ribeye to be 1.2 times the scan wt (divided by 100)

so
1300# scan wt
needs to have a ribeye scan of 15.6 sq in.

We have purchased bulls that are 1.1 or so but will not buy one with that ratio less than 1. I have always been arguing that ribeye area is currently improperly tied to scan wt.

 

[Boot Jack Bulls]

Thanks Butch and Jscunn! That's the kind of info I was looking for. I'm always trying to learn how people apply the information given, in an effort to understand the market better. Thanks!

 

[Ebenezer]

Carcass data is based on genetics that are more heritable than maternal traits such as fertility. In a breed, like Angus, that was once prized for functional females to the point of being labeled "the maternal breed" or something like that, the chase of carcass data has undermined the search and selection of cattle, bulls and cows, which produce fertile, sound (feet, legs, udder, temperament) females. Sure it is easy to scan REA as compared to waiting 7 years to see if the daughters are ideal. Where are the problems with Angus today? Feet, legs, fertility, udders and disposition.

As some have posted, there are breeds with excellent terminal traits, such as Limousin. Most Angus are now in a state of purgatory somewhere between true maternal and true terminal. Odd that many bull test bulls today can excel on YW but be low on REA/CWT. It is obvious in the two tests in SC especially on sons of nationally promoted AI bulls and from "progressive herds" that use most AI. To bump the REA/CWT ratio up there is generally a mammoth animal to the point of being an outlier or the frame size has to be reduced to get the numbers to play out for high and higher REA/CWT.

My #1 priority is the cow herd. I don't mind bulls that are bulls but I sure want cows that are great cows. Excess fat and extra muscle never made a cow any better but will actually work against the natural type that is most functional. If nothing else, look at the pictures that Bonsma used. The cows had balanced hormones and had a feminine type.

My bias is evident. A two breed cross is ideal as long as the females are superior in function as the base and the second breed bull has terminal traits so that all calves can excel in the feedlot. American agriculture did away with dual and triple use animals years ago: cattle for milk, meat and possibly draft, chickens for both meat and eggs, ... to be more efficient. Yet the beef industry, and especially breed organizations, still try to promote and set up data for the same thing: maternal and terminal.

 

[Jessica06]

Personally, I think the REA/live wt. ratio is more important than actual REA by itself. If a bull's yearling weight is 1500 with a 16" ribeye...well, he'd better have one that big when he weighs that much! That being said, we don't use REA as a deal breaker, but the bulls that we select to use are more muscular and a bigger RE typically just goes along with it.

 

[Post Oak]

Personally, I think the REA/live wt. ratio is more important than actual REA by itself. If a bull's yearling weight is 1500 with a 16" ribeye...well, he'd better have one that big when he weighs that much! That being said, we don't use REA as a deal breaker, but the bulls that we select to use are more muscular and a bigger RE typically just goes along with it.

How about some of the 4 to 5 frame Trask or Wye cattle that have 1.4 inches of ribeye per hundredweight? You kill them at 15 months and they weigh 1000 pounds, they will have a 14 inch ribeye.

 

[elkwc]

Personally, I think the REA/live wt. ratio is more important than actual REA by itself. If a bull's yearling weight is 1500 with a 16" ribeye...well, he'd better have one that big when he weighs that much! That being said, we don't use REA as a deal breaker, but the bulls that we select to use are more muscular and a bigger RE typically just goes along with it.

How about some of the 4 to 5 frame Trask or Wye cattle that have 1.4 inches of ribeye per hundredweight? You kill them at 15 months and they weigh 1000 pounds, they will have a 14 inch ribeye.

The problem is if a feeder won't reach 1,350-1,400 in this area when they are finished then they are docked. It is hard to get the small framed cattle to that weight with a reasonable cost of gain.

 

[Kingfisher]

Accuracy on carcass traits are so low before a sire is 8-10 yrs old that when it comes to sire selection I end up looking at $ indexes more than individual carcass traits.
Can you tell me/us how you use $ index data? I know it's useful just never been able to wrap my pea brain around it. Thanks in advance Butch

 

[Ebenezer]

Personally, I think the REA/live wt. ratio is more important than actual REA by itself. If a bull's yearling weight is 1500 with a 16" ribeye...well, he'd better have one that big when he weighs that much! That being said, we don't use REA as a deal breaker, but the bulls that we select to use are more muscular and a bigger RE typically just goes along with it.

How about some of the 4 to 5 frame Trask or Wye cattle that have 1.4 inches of ribeye per hundredweight? You kill them at 15 months and they weigh 1000 pounds, they will have a 14 inch ribeye.

And if these cattle are typical of sale bulls and fed steer data the rind fat will be about 100+ pounds of trim and waste plus excessive seam fat. Type matters in BW, CED, muscling, skeletal size and waste. There has to be a balance.

My concern/experience is that some +CED bulls will have lesser muscling and the intake of the average amount of grazing leaves the animals no option but to put on extra fat to use the energy that the extra or normal amount of muscles would have utilized.

Are the true low BW bulls low weight because they are small, thin muscled or what? Something has to be given up to make them lighter. And BW and calf shape is generally linked to MW and mature size. If a calf is tall at birth he will generally be tall at maturity. If he is squatty at birth, ... Somehow, and most of you can tell me, but frame size moderates a lot of this to allow easier birth, to a point, of the calf's shape being longer and less prone to hang at the shoulders or the hips, the muscles can be smooth and not bunched and the appropriate amount of muscling allows animals to avoid normal intake leading to obesity.