Rule of thumb

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Jogeephus

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Does anyone know of a rule a thumb that could be applied to the weaning weight of a heifer's first calf compared to its later calves? Ie, the first calf will be X% lighter than the others it may have in its lifetime. Just wondering.
 
i always figure that a hfr will wean a calf close to a 50-100lb smaller than she will as a cow but thjis s not always true

I had a hfr last yr wean a calf at 502lbs around 200 days old and she weaned one this yr at 510lbs at around the same age
her herd mates calves were about 50 lbs lighter than hers last yr but right with her calf this yr
 
assuming that you are making genetic improvements with each generation of females retained, her first calf doesn't necessarily have to be any lighter at weaning than the rest of the cowherd. and if you are breeding heifers a few weeks earlier than the cowherd (making her first calf older at weaning) they probably shouldn't be lighter.

in my opinion, the thing that is most antagonistic to heifers weaning calves of equal or greater weights than the cowherd (or equal or greater weights than her future calves) is the use of the infamous "low birthweight heifer bull" that many producers use on first calf heifers. but i would also agree with those who realize that a light first calf weaned alive is much more profitable than a big first calf pulled dead.

so i guess my answer would be: too much depends on the bull for there to be a credible rule of thumb.
 
Thanks for the information. I was just wondering about this in very general terms based on the physiological maturity of the cow and not genetically. Frankie, I think the chart is pretty good cause I've witnessed the bloom with age myself.

All things being equal, do you think a calf that exceeds all its contemporaries on weaning weight shows it has something that might be worth watching for future or just a fluke.
 
Jogeephus":4qv0p9r2 said:
All things being equal, do you think a calf that exceeds all its contemporaries on weaning weight shows it has something that might be worth watching for future or just a fluke.

It depends. Those really high weaning weights usually lead to larger mature size.
 
Hey Jo,

I started a discussion on CT in Jan '08 about this:
http: //cattletoday.com/forum/viewtopic.php?f=8&t=43609&st=0&sk=t&sd=a&hilit=heifer+wean+weight

The results are still true today for me. Heifers wean calves that are 50-100 pounds lighter than the herd average, and that heifers second calf almost always jumps up to the average. I have had a few heifers that raised unusually large calves, but they are few and far between. Oh, and one of the heifers that raised a huge calf wasn't able to breed back - so she's useless as a study.
 
irked":23qjlahk said:
in my opinion, the thing that is most antagonistic to heifers weaning calves of equal or greater weights than the cowherd (or equal or greater weights than her future calves) is the use of the infamous "low birthweight heifer bull" that many producers use on first calf heifers.

The main reason for lighter birthweights is the lack of production of milk in younger cows that are still gorwing.
The infamous "low birthweight heifer bull" is used a lot but that is just poor bull selection criteria, i.e. single trait selection. There are lots of bulls that will throw low BW but will still have the desired weaning and butchering weights. We've used low BW bulls on cows and heifers in the same year and the heifers calves weaned lighter then the cows, that's a cow production angle not the bulls.
 
Jogeephus":345gupgz said:
Thanks for the information. I was just wondering about this in very general terms based on the physiological maturity of the cow and not genetically. Frankie, I think the chart is pretty good cause I've witnessed the bloom with age myself.

All things being equal, do you think a calf that exceeds all its contemporaries on weaning weight shows it has something that might be worth watching for future or just a fluke.

I think it bears watching. It may be just a fluke, but some of those flukes carry over to the next generation.
 
Jogeephus":3aglk6qw said:
Thanks for the information. I was just wondering about this in very general terms based on the physiological maturity of the cow and not genetically. Frankie, I think the chart is pretty good cause I've witnessed the bloom with age myself.

All things being equal, do you think a calf that exceeds all its contemporaries on weaning weight shows it has something that might be worth watching for future or just a fluke.
Also let me clarify my earlier response with all things being equal as for feed conditions hfrs will usually wean a smaller calf for one reason that hfr herself is taking alot of the nutrients she is taking in because she is still growing herself instead of putting it all in milk where as a cow is just maintaing herself and therefore more of her intake goes into milk production
now if you feed that hfr most of the time her calf will equal that of a cow but the ? is can you justify the input $ of feed for the weight gain on the calf
in my experience I can't because if you have a 550lb calf out of a cow and a 475 lb calf out of a hfr the 550 weight calf brings a $1.00 per lb and the 475 lb calf will bring a $1.10 so you are only talking about a income of $27.50 more for the cows calf over the hfrs and $27.50 will not buy enough feed to get the other calf to 550lbs
 
Along the same lines of heifers' milk production...

Have anyone ever noticed certain sires' daughters being really average or below average milkers for their first lactation and then really milk very well from the second lactation onwards? I have quite a few daughters of what was at the time a national trait leader bull for milk with an accuracy of .96 His first 5 daughters raised just average or slightly below average calves the first year and now although the calves are still young its pretty evident that they really milk this time around. Of his next 6 daughters that just calved now for the first time only one that was out of a very milky cow looks like she'll milk according to her sire's EBVs, 1 is about average for a heifer in my herd and the others are slightly below average with one really below average.
 
KNERSIE":30jeaa2i said:
Along the same lines of heifers' milk production...

Have anyone ever noticed certain sires' daughters being really average or below average milkers for their first lactation and then really milk very well from the second lactation onwards? I have quite a few daughters of what was at the time a national trait leader bull for milk with an accuracy of .96 His first 5 daughters raised just average or slightly below average calves the first year and now although the calves are still young its pretty evident that they really milk this time around. Of his next 6 daughters that just calved now for the first time only one that was out of a very milky cow looks like she'll milk according to her sire's EBVs, 1 is about average for a heifer in my herd and the others are slightly below average with one really below average.
I wonder about ther heretability of milk. We had one angus cow that raised a boomer of a calf every year. We bred her 2 an above average for milk angus bull and her daughter raised a dink, gave her daughter a second chance and the calf was even smaller weaning then the first. Same old cow bred to an above average for milk Polled Hereford bull. The daughter raised 2 substandard calves before she hit the road.
 
I wonder about ther heretability of milk.

Its pretty low, can't remember the exact figure without looking it up.

I have tried for long enough to breed milk into low milking cows to know that its a fool's game, but these heifers in question are all out of average or above average cows for my herd otherwise they wouldn't have been retained for replacemnets.
 
KNERSIE":1l8peu00 said:
I wonder about ther heretability of milk.

Its pretty low, can't remember the exact figure without looking it up.

I have tried for long enough to breed milk into low milking cows to know that its a fool's game, but these heifers in question are all out of average or above average cows for my herd otherwise they wouldn't have been retained for replacemnets.

I saw almost the same thing happen with a Holstein bull. His daughters milked like a house a fire and their daughters would make a sheep look like a heavy milker. But none of his sons sired a cow that was worth milking.
 
good discussion! the noble foundation has an interesting article done several years ago to dispel some of the myths related to replacement heifers - - including the myth that they have to wean lighter calves.

http://www.noble.org/Ag/Livestock/Heife ... index.html

of course there are too many things that we don't know about this study for it to have value for everyone. we don't know about things like creep feeding or other differences in their management of first calf heifers. many larger operations run them separately so that they are able to provide the first calf pairs with superior nutrition. with the investment required to make a productive cow out of a heifer, that's a good idea if one can do it. but many smaller producers have to throw them in with the cowherd much sooner. many believe that it's best to throw them in with the cowherd after weaning - - "let them learn how to be a cow." i don't think either school of thought is necessarily wrong.

as to the argument that the first calf heifer is still growing, therefore putting more of the resources consumed into growth and less into lactation, that is very true. but it also has some room for variability. was she bred at 65% of mature weight or was she pushed harder to gain an extra 100+ pounds as a yearling? so much of this discussion on growth in the young cow relates to differences in heifer development pre-breeding and early in gestation. some producers push heifer calves harder after weaning or push them harder as yearlings in an attempt to negate some of the growth that would otherwise be required during their first lactation.

it would seem to me that pushing a heifer harder to achieve more of her mature weight at breeding or in the first few months following breeding could be offset with the money derived from expecting her to wean a heavier calf. having more of the growth done pre-breeding or shortly after breeding would also almost certainly have some impact on rebreeding as well. if a young cow with her first calf is still growing to the extent that she weans a lighter calf, wouldn't she also still be growing to the extent that she would have a harder time with rebreeding? for people who breed heifers at lighter weights, how many of them will skip a calf at some point early in their lives and what is the cost of that? some producers are perfectly willing to accept as fact that a young cow that calves early in life with minimal inputs into her development will skip a calf, while others are more demanding. once again, if something is working for you, it's not necessarily 'wrong' to be doing it. i'm a firm believer in people continuing to do what works for them - - just as long as they keep in an open mind to improvements.

but no matter whether it's fertility (breeding at the front end of bull turnout) or production (weaning a calf equal to her more mature herdmates), if we demand more from our replacement heifers instead of making excuses for them, we'll get where we want to be much faster.
 
dun":pjfmgkou said:
The infamous "low birthweight heifer bull" is used a lot but that is just poor bull selection criteria, i.e. single trait selection. There are lots of bulls that will throw low BW but will still have the desired weaning and butchering weights.

that is so true. i still see ads in some of the livestock publications advertising "longhorn x angus heifer bulls" or "jersey x angus heifer bulls" and one time even saw an advertisement for "longhorn x jersey" bulls. as you say dun, there are many good choices for low birthweight and calving ease that will also give acceptable or even superior growth to weaning or yearling. i realize that some people just don't want to take any chances and want a trouble free calving season. but if i thought i had to use a jersey or longhorn bull on heifers i would feel like i needed to change the way i develop or select those heifers.
 
My bottom line for our heifers is that she needs to raise a calf that gained 1.8 lbs per day (works out to 450 lbs or so on 205 days). I have discovered using my records in the past that if she can't do this in her first year, she won't improve enough in the next year to make it worth feeding her to find that out. I might cull the odd one that would have surprise me, but I think that the cost of feeding all the others negates that possibility.
 
but if i thought i had to use a jersey or longhorn bull on heifers i would feel like i needed to change the way i develop or select those heifers.

Absolutely, in the seedstock business its even more true. A heifer that can't have a calf of breed average size or slightly above on her own isn't worthy of being registered.

My bottom line for our heifers is that she needs to raise a calf that gained 1.8 lbs per day (works out to 450 lbs or so on 205 days). I have discovered using my records in the past that if she can't do this in her first year, she won't improve enough in the next year to make it worth feeding her to find that out. I might cull the odd one that would have surprise me, but I think that the cost of feeding all the others negates that possibility.

The important part is you have records and a strategy, most commercial cattlemen I know seldom even know which calf belongs to which dam and since they have no idea on birthdates they really don't know who is doing the work and who is loafing at his cost.
 
I expect the first calvers to wean a calf similar in weight to any of the other cows in the herd. The reason being I always use the latest purchased bull to breed the heifers and expect these calves will have the best genetics in the herd. On any given year I will usually pick 15-20% of my replacements from the group of heifers out of first-calvers. It is impossible to tell the difference in size. As far as milk heritability goes, 40% seems to be stuck in my head.
 

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