Ideal Birth Weight

[Chuckie]

I am trying to figure out the birth weight on the EPD chart for each bull. I am reading where the first number is for the bull listed. Then the second number, is for a comparing bull. I am not sure about this. Seems they would have one set number for the second bull as a total average. The second number is different in each chart. How do they come up with the numbers for the second bull? What is the ideal weight comparison on the charts. I see some that list the birth weight of the first bull as 4.1 then the second bull as 1.0. Then it says that the first bull should sire calves averaging 3.1 pounds heavier at birth. What numbers are you looking for in the birth weight column? Chuckie

 

[Frankie]

I am trying to figure out the birth weight on the EPD chart for each bull. I am reading where the first number is for the bull listed. Then the second number, is for a comparing bull. I am not sure about this. Seems they would have one set number for the second bull as a total average. The second number is different in each chart. How do they come up with the numbers for the second bull? What is the ideal weight comparison on the charts. I see some that list the birth weight of the first bull as 4.1 then the second bull as 1.0. Then it says that the first bull should sire calves averaging 3.1 pounds heavier at birth. What numbers are you looking for in the birth weight column? Chuckie

Where are you reading this information? Is it online somewhere?

First, EPDs are generally breed specific. You shouldn't compare Angus BW EPDs with any other breed BW EPDs.

Second, every bull should have his own set of EPDs. EPDs are produced by weighing relatives of an individual bull and calves sired by his relatives. If you only have one bull to consider, compare his EPDs to the breed average.

Whatever you're reading is accurate. You would Expect calves sired by a bull with a BW EPD of 4.1 to weigh 3 lbs more at birth than calves sired by a bull with a BW EPD of 1. Again, assuming they are bulls of the same breed.

The American Angus Association recommends using a bull with a BW EPD of less than 3 on heifers. Personally, I stay around 2 on heifers. As Angus are generally an easy calving breed so I don't worry much about the BW EPDs of bulls that I'm using on mature cows.

 

[Chuckie]

Frankie, I found this site: http://ag.arizona.edu/pubs/animal/az9611.pdf It explains the two sets of numbers under the birth weight column.
When I pull up the charts on the bulls for Angus, I see different numbers under each bull of the same breed. I went to Bovine Elite and pulled up the first two bulls that they list. The first bull, his birth wt is 1+ 2.3 and the second number is .05. The second bull that is listed, his birth wt number is 4.2 and the second number is .92. I am comparing Angus bulls only. But I am not sure how they come up with these numbers in the first column and the second column. People tell me not to question things like this, but how else will you explain what you are talking about?? I try not to be a total idiot that thinks they know it all. I'll settle with just being the idiot. Chuckie

 

[txag]

Frankie, I found this site: http://ag.arizona.edu/pubs/animal/az9611.pdf It explains the two sets of numbers under the birth weight column.
When I pull up the charts on the bulls for Angus, I see different numbers under each bull of the same breed. I went to Bovine Elite and pulled up the first two bulls that they list. The first bull, his birth wt is 1+ 2.3 and the second number is .05. The second bull that is listed, his birth wt number is 4.2 and the second number is .92. I am comparing Angus bulls only. But I am not sure how they come up with these numbers in the first column and the second column. People tell me not to question things like this, but how else will you explain what you are talking about?? I try not to be a total idiot that thinks they know it all. I'll settle with just being the idiot. Chuckie

my guess is the second numbers (.05 & .92) are accuracies.

 

[Chuckie]

Accuracies of what? I am totally green to these charts. Accuricies of what the bull sires on the average by weight?

 

[txag]

Accuracies of what? I am totally green to these charts. Accuricies of what the bull sires on the average by weight?

the accuracy of the epd. a .92 accuracy means that you can be 92% confident that the bull's epd is what it says it is. conversely, a .05 accuracy means that the confidence is only 5%. the more calves the bull sires and the more data going into the system, the higher the accuracy. animals that have no offspring will not have accuracies but will have PE which stands for "pedigree estimate".

 

[Chuckie]

Thanks Frankie and txag. Now I can say that I learned something today.

 

[Chuckie]

There are some of the birth weights that show a first number that is like this: 1+1.3 Then the next number is .05. Please explain the first number with the plus. I can't figure it out.

 

[Jake]

it means it's a positive 1 a minus would mean a negative one. so in theory a plus one bull would have throw a calf 2 pounds heavier than a minus one bull.

 

[txag]

There are some of the birth weights that show a first number that is like this: 1+1.3 Then the next number is .05. Please explain the first number with the plus. I can't figure it out.

ok, you made me look it up :lol:

it looks like an "I", not a "1". off-hand, i can't think what an "I" would stand for. "Interim"? maybe Frankie can help.

the epd would be 1.3 with an accuracy of 5%

 

[txag]

not trying to change the subject but does everyone else have the same ad at the top of this thread: "MEAT....it's what's rotting in your colon"?

 

[Jake]

I've always thought it meant interim. cuzz you never see it on a proven animal

 

[txag]

I've always thought it meant interim. cuzz you never see it on a proven animal

that's what i would think but one of the bulls in question is a '99 model. surely some calves have been registered?

 

[txag]

not trying to change the subject but does everyone else have the same ad at the top of this thread: "MEAT....it's what's rotting in your colon"?

never mind. it's not there anymore.

 

[Frankie]

There are some of the birth weights that show a first number that is like this: 1+1.3 Then the next number is .05. Please explain the first number with the plus. I can't figure it out.

ok, you made me look it up :lol:

it looks like an "I", not a "1". off-hand, i can't think what an "I" would stand for. "Interim"? maybe Frankie can help.

the epd would be 1.3 with an accuracy of 5%

If you're looking at Angus EPDs, yes, an "I" stands for interim. Some breeds use the PE for pedigree estimate (I think). For an Angus calf to get Angus EPDs, a calf's sire and dam must have real (not interim) EPDs. If either parent has interim EPDs, the calf won't have EPDs until his performance information (BW, WW, etc.) is reported to the Association in a proper contemporary group. The calf will then have Interim EPDs and the "I" on his sire or dam's EPDs will disappear. The accuracy figure reflects how much information has been reported on tp the Angus Association on an animal's relatives.

 

[Frankie]

I've always thought it meant interim. cuzz you never see it on a proven animal

that's what i would think but one of the bulls in question is a '99 model. surely some calves have been registered?

You can register calves with the Angus Assn and not report performance information into the AHIR program. And it's that informtion that makes up EPDs.

 

[Chuckie]

Yep, you're right. It is an "I." I guess I was expecting it to be a number in the number column. The bull I was looking at was a 2003 model on the Bovine Elite page. His name is "Big Elban." Thanks for clearing that up. Next time, I will wear my glasses.

 

[PASS]

What I don't understand about EPD's is, do they take lets say, 100 bull calves, raise them under controled conditions and then use thier numbers only? Do they take all the birthweights from this group and get the mean or the average and use that as ZERO. The rest are a + or - from that number. Or, is this a cumlative number from all bulls of this breed for the last nubmer of years?

I don't understand where the average numbers come from. :?:

Thanks

 

[Frankie]

What I don't understand about EPD's is, do they take lets say, 100 bull calves, raise them under controled conditions and then use thier numbers only? Do they take all the birthweights from this group and get the mean or the average and use that as ZERO. The rest are a + or - from that number. Or, is this a cumlative number from all bulls of this breed for the last nubmer of years?

I don't understand where the average numbers come from. :?:

Thanks

First understand that EPD AVERAGES change every year. The Angus Assn averaged all the BW, WW and YWs reported to the Association in 1979 (I think that's the year; someone correct me if I'm wrong, please) and called that 0. Other breeds selected a year and set that year as 0 for their breed. But every year there are changes to the average BW of calves born, weaned and yearling weights, etc. so the average for the breed changes from year to year. Am I making sense? Today, the average BW EPD for Angus is 2.5, WW is 36 and average EPD for YW is 68. So the Angus breed has added 36 lbs of weaning weight and 68 lbs of yearling weight for an increase in BW of only 2.5 lbs. Not too shabby in my mind.

The Angus Assn has a program called Angus Herd Improvement (AHIR). Breeders all across the US weigh calves at birth, weaning, and yearling within a contemporary group of at least two, more is better, and report those weights to the Assn. Those weights reported are the basis for Angus EPDs. I assume all other breeds do much the same to get their EPDs.

If I'm not being clear, please let me know and I'll try to do better....

 

[PASS]

That does make sense and your post was very helpful.

Thanks!

Pat