Projecting Birth Weights

[slick4591]

Any formulas to project birth weight from a first timer bull?

 

[slick4591]

I guess the deafening silence means no.

 

[SRBeef]

Isn't that what EPD's are for?

Jim

 

[dun]

Isn't that what EPD's are for?

Jim

EPDs will not give you a projected BW, all it will do is statisticly tell you what difference in weight you can expect when comparing 2 bulls/cows.

 

[slick4591]

Guess I was hoping for a way to get a decent guesstimate as to what I could expect. Thanks tho.

 

[dun]

Guess I was hoping for a way to get a decent guesstimate as to what I could expect. Thanks tho.

Put up a dart board with numbers on it and throw darts at it. That's about as accurate as it's gonna get.

 

[vclavin]

Any formulas to project birth weight from a first timer bull?

Cow/heifer is responsible for the majority of the BW. Heifer's first calf will be approx 90% of what she will produce at maturity. You then need to add/subtract due to environment, then the big boy gets his share...usually shortens/lengthens gestation. High WW & YW EPD bulls tend tend increase rate of growth in calf...as does using a cross on the female.
EPD's are much easier than darts... a little more accurate too! LOL
Valerie

 

[dun]

Any formulas to project birth weight from a first timer bull?

Cow/heifer is responsible for the majority of the BW. Heifer's first calf will be approx 90% of what she will produce at maturity. You then need to add/subtract due to environment, then the big boy gets his share...usually shortens/lengthens gestation. High WW & YW EPD bulls tend tend increase rate of growth in calf...as does using a cross on the female.
EPD's are much easier than darts... a little more accurate too! LOL
Valerie

But they aren;t going to give you weights!

 

[MO_cows]

Look at the birth weights in the pedigree if the animal is registered. Plus the bull's own birth weight, the CED EPD and the BW EPD gives you an educated guess.

 

[slick4591]

Cow/heifer is responsible for the majority of the BW. Heifer's first calf will be approx 90% of what she will produce at maturity. You then need to add/subtract due to environment, then the big boy gets his share...usually shortens/lengthens gestation. High WW & YW EPD bulls tend tend increase rate of growth in calf...as does using a cross on the female.
EPD's are much easier than darts... a little more accurate too! LOL
Valerie

Look at the birth weights in the pedigree if the animal is registered. Plus the bull's own birth weight, the CED EPD and the BW EPD gives you an educated guess.

Thanks for the info!

 

[vclavin]

Any formulas to project birth weight from a first timer bull?

Cow/heifer is responsible for the majority of the BW. Heifer's first calf will be approx 90% of what she will produce at maturity. You then need to add/subtract due to environment, then the big boy gets his share...usually shortens/lengthens gestation. High WW & YW EPD bulls tend tend increase rate of growth in calf...as does using a cross on the female.
EPD's are much easier than darts... a little more accurate too! LOL
Valerie

But they aren;t going to give you weights!

Exactly! Bulls don't throw certain "weights" cows do, this just gives you a guess as to what each individual female may produce. That's it.
Valerie

 

[slick4591]

I guess I've heard to many farmers say they gotten rid of bulls because they were throwing large calves. I don't have birth weights on my heifers, but I do on my bull.

 

[dun]

Exactly! Bulls don't throw certain "weights" cows do, this just gives you a guess as to what each individual female may produce. That's it.
Valerie

A cows EPDs aren;t going to tell you the weights either. We have a cow that for her first 6 calves averaged 78 lbs. Last year she had a 115 lb bull from a bull that has usually thrown 70-75 lb calves, this year she had a 65 lb heifer and he isn;t noted for small calves.

 

[cow pollinater]

EPD's are designed to average out our management decisions by taking a large sample of cattle so that we see real trends over years instead of false trends caused by poor conditions on one farm or good conditions on another. Unless you have a HIGH reliability bull, it's a crapshoot... Good management will help your odds.
I've helped people pull calves out of proven four star calving ease bulls that were monsters while the people stood there and blamed me since I was the one that dumped the straw and I've seen one star bulls that are suposed to be cow killers deliver calves that weren't out of line with any good calving ease bull but the recieving animals were managed better for calving ease.
You can hedge your bets quite a bit by managing your heifers wisely. Lots of people just pump their heifers full of great feed all the time and then complain when the calves are big. :bang: You CAN manage for smaller calves if you're concerned about it.

 

[slick4591]

My question was about the bull I just bought, but not using this season on my heifers, and since I only have heifers I am concerned. The bull I am using is of Italian genetics and having to go by their EPD's. They use a scoring system of 100 as average. The bull I'm using has a calving ease score of 98, which I interpret that he throws less than average sized calves. I guess I'm worried because many have told me not to breed heifers full blood because of the size calves. Since my animals are not under foot I can't watch them as closely as I would like.

 

[cow pollinater]

I think??? that by their system higher is always more favorable no matter what the trait. I don't deal with out of country genetics very often so I'm not sure but I believe that's the case.
A 98 score would be somewhere in the vicinity of a 9-10% percent calving ease dairy bull here or a three star calving ease beef bull.... Not the end of the world but procceed with caution. Look at both cow families and make sure it's not an average of a calving ease animal being mated to a killer. If that's the case you don't know whch side of the family he takes after until you see the results. :shock:

 

[slick4591]

These are the EPDs. Now I'm really confused.

Breeding 115
Meat 122
Muscularity 114
Daily Growth 102
Birth Ease 120
Calving Ease 98
Size 100

Adding:

The goal when breeding the Piemontese is to produce easily born calves with ahigh growth potential and well developed muscular masses, and to breed femaleswith good calving ability. Selected traits can be divided into two types: productivetraits (related to meat production) and reproductive traits (related to calving).
All indices are expressed on the same scale. This scale is based on 100, whichis the average genetic value of all A.I. sires, and has a standard deviation of10. The best 15% of all sires have values exceeding 110, whereas only the best2% of sires have an index above 120.
On-station performance testing increases the accuracy of comparisons between thebulls, because the environmental factors affecting the results (feeding, housing,health treatments, etc.) are the same for each animal. As a result, the differencesobserved between the animals are mostly due to their genetic potential.
The functional suitability of bulls is also assessed through morphological evaluation;the legs are evaluated to calculate a genetic index that is included with theselection indices.
The result of a calving is influenced by calf size and by the dam’s abilityto calve (which is mainly determined by her pelvic area). The simultaneous presenceof these two biological factors results in two traits; namely, Birth ease andcalving ease.
Each year, over 80,000 calving records are collected and registered in the PiemonteseHerd Book.
Two selection indices are used for the Piemontese breed: the breeding index andthe meat index.
The breeding index aims to identify the best sires for producing breeding females;the meat index seeks to select the best sires for producing animals to be fattened.
Breeding Index = 0.4 * calving ease +0.2 * Birth ease +0.2 * muscularity +0.14* growth +0.06 * legs
Meat Index = 0.2 * calving ease +0.4 * Birth ease +0.2 * muscularity +0.14 * growth+0.06 * legs
The difference between the two indices lies in the different weights assignedto calving ease and Birth ease, which are inverted. Reproductive traits accountfor 60% of both selection indices, productive traits for 34%, and legs for 6%,respectively.

http://lg.anaborapi.it/testi/bbf.dll?1000

Maybe it's my brain, but could someone translate this for me? It's from the Italian genetics company's web site.

 

[dun]

What I don;t undertsand is the the differnce between calving ease and birthing ease. Unless calving ease is what we refer to as calving ease maternal, i.e. his daughters ability to calve unassisted. Sur doesn;t make sense to me

 

[vclavin]

My question was about the bull I just bought, but not using this season on my heifers, and since I only have heifers I am concerned. The bull I am using is of Italian genetics and having to go by their EPD's. They use a scoring system of 100 as average. The bull I'm using has a calving ease score of 98, which I interpret that he throws less than average sized calves. I guess I'm worried because many have told me not to breed heifers full blood because of the size calves. Since my animals are not under foot I can't watch them as closely as I would like.

Have you had the vet examine the heifers for a pelvic size? If the size is too small, it won;t matter how "calving ease" the bull is... the heifer will have trouble. Selecting for good pelvic scores over time will help stop calving problems.. not all problems.. but those due to pelvic area too small.
Season of the year can affect BW by 5 lbs. I have forgotten which season was better for lower BW.
Valerie

 

[Jeanne - Simme Valley]

By their description, I'm going to "guess" calving ease is the size/shape of the calf and birthing ease is the ability of the cow to calve (which would be closer to our MCE for us???)
They also said all indices were based on the same scale - so 98 would be LESS than desirable.

Now, I'm going to make a VERY BROAD statement - All these EPD's are based on Italian cattle. "Most" European native breeds are bigger than ours and could handle much larger calves than our cattle. I would NOT recommend using a fullblood bull on American born raised heifers unless they are fullbloods and/or are equal in size as European fullbloods.
That's how Simmental got such a bad rep right in the beginning. Breeders took the imported fullblood semen and "tried" it on their cows to see what the new breed would do. Well, you don't put a 2500# (and bigger) bull on 900-1100# cattle and not expect calving difficulties :bang: