Developing Replacement Heifers

[Oldtimer]

An article that was in the last Montana Angus News- so I assume she is talking angus numbers:

Beth M Blevins,DVM was born and raised in Cut Bank, Montana. She attended Carrol College in Helena MT, where she found that snow actually piles up on fence posts and power lines. After graduating from Colorado State University in Fort Collins, Colorado, she completed a large animal internship at Washington State University in Pullman Washington. She has practiced in the Ronan, Montana area since 1987.



One chore for fall
involves selection of replacement heifers and development of those heifers. The tendency to choose the large well doing heifers results from eye appeal. The biggest heifers just attract the most attention. Consistently choosing the largest heifers tends to increase frame score
on the herd. A hip height of 47 to 50" for a 10 month old heifer
would be a frame score of 5 or 6 which is a moderate frame score.
At 20 months that same heifer should have a hip height of 50 to 52"
as measured when the heifer is standing square, sighted at the hook
bones. Having an idea of the
desired frame score on the cow herd or even knowing the average height in the cow herd now and whether an
increase, decrease or maintenance of that frame is desired helps
determine a target weight for replacement heifers. Having a target
weight for the heifers gives a producer a tangible goal. Angus heifers,
as well as other breeds that are not Brahma or Brahma-cross, reach
puberty at 60-65% of their mature weight. Using the frame score to predict mature weight then allows computation of a target weight for puberty. For example a frame score of 5 in a 10-month old heifer
should have a hip height of about 48" and a mature weight of
1173#. Sixty percent of 1173# is 704# as the target weight for
puberty. Hitting the target weight at the start of the breeding season
gives that heifer the best chance of breeding. Ideally heifers
should have an average daily gain from weaning to the start of
1 to 1.5# per day. Adequate, but not excessive, gains ensure proper udder development and milking ability. Protein and energy requirements
met in a balanced ration to achieve a body conditon score of
6 is ideal. Heifers gaining on average from weaning to breeding, more
than 2# per day had decreased fertility as did thin heifers. In addition,
the fatter
heifers have a decrease in lifetime weaning weights because of decreased milk production. If heifers are thin for part of the period from weaning
to breeding, then fed more to hit the target weight, the fertility and
milking ability are preserved. Looking at the entire weaning to
breeding period for the average of 1 to 1.5# daily gain and reaching
the target weight with a body condition of 6 is vital.

PELVIC AREA AND FRAME SCORE
Measuring pelvic area as a selection criteria for heifers facilitates the process if properly interpreted. Simply choosing the heifers with the
largest pelvic area will result in selecting for larger frame score. Unfortunately the larger frame score heifer has a larger frame
score calf and calving problems still encountered. Pelvic measurements taken with a caliper inserted rectally, finds the narrowest height
and width in centimeters. The product of those measurements yields
the pelvic area in centimeters. Instead of choosing bigger is better,
the best use of pelvic area measurement is to set a minimum of
150 sq centimeters at one year of age. Any heifer measuring less
is culled, but no preference is given to heifers measuring larger.

REPRODUCTIVE TRACT SCORE
If pelvic area is
being measured a reproductive tract
score can be determinded at the same time.
If the uterine horn is less than 20 mm diameter and the ovaries are the size of peanuts at 6 to 8 weeks prior to the start of breeding season,
the heifer is either too young, too thin or was implanted as a calf.
Prospective replacement heifers should never be implanted with
growth promotants as implantation is associated with fewer heifers
cycling and conceiving, especially younger heifers and heifers
implanted more than once. A reproductive tract score of 1 would
be assigned to that heifer. A 5 reproductive tract score has a
uterine horn diameter greater than 30mm with good tone and ovaries
the size of a large lima bean with follicles and a CL (corpus luteum formed from the follicle after a heat cycle). A score of 4 would have
uterine diameter of 30mm and and lima bean sized ovaries with follicles.
Heifers should have a 4 or 5 reproductive tract score 6-8 weeks
prior to breeding season.

Choose well when selecting replacement heifers. Pay attention
to thier development with feed and vaccinations. The heifers are
the future of the cowherd.

 

[mlazyj]

Well the way things went this year a person should have been picking the biggest the end of October when we shipped .After post weaning stall and a couple of months zero weather a guy is going to have break out the grain bucket to make 700# by May.

 

[HomePlaceAngus]

What you are saying oldtimer makes a lot of sense. However attending sales all year long at the largest Angus breeders, I find that the top selling group of females are also the largest females. On one hand we say that we should be breeding for a moderate female and then the market is demanding a larger female. Makes no sense.

 

[xxbrand]

HomePlaceAngus I agree with you 100%. At the angus sales I have attended this year the top selling heifers were always the largest. Some think breeding for moderate size female would be better, but many producers today seem to think that bigger is better. They must know if you retain heifers with heavy weaning weights they will be the easiest and cheapest to feed out for a target weight for breeding and calving. Although heifers don't have to be big to be profitable.

 

[Oldtimer]

What you are saying oldtimer makes a lot of sense. However attending sales all year long at the largest Angus breeders, I find that the top selling group of females are also the largest females. On one hand we say that we should be breeding for a moderate female and then the market is demanding a larger female. Makes no sense.

Yep-- some of those same folks that talk about wanting the proverbial 1200 lb mature cows-- wonder why (after they bought those really nice feedlot wintered yearling heifers that had YW of 900-1000 lbs in the spring) have a bunch of heifers go downhill when they hit grass- and all those that do breed up make mature cows that end up weighing 1400-1500+....

My heifers are roughed thru the winter on forage only - (replacements I kept this year averaged 581 lbs WW Nov. 2nd) and most will weigh somewhere around 700-750 (about 3/4 lb a day gain) when they go out on grass in the spring...I like to have them gaining on grass when the bulls go out as I think they breed up faster...

900-1000 is closer to the weight my coming 2's are when they calve...

 

[HomePlaceAngus]

Our heifers weigh around 1200 when they calf at 2 yo and some of our mature cows weigh 1700 - 1900 lbs. Like I said, we can talk about the 1100-1200 lb cows but it seems that the customers want the larger ones. Our herd winters on fiscue hay.

 

[angus9259]

HomePlaceAngus I agree with you 100%. At the angus sales I have attended this year the top selling heifers were always the largest. Some think breeding for moderate size female would be better, but many producers today seem to think that bigger is better. They must know if you retain heifers with heavy weaning weights they will be the easiest and cheapest to feed out for a target weight for breeding and calving. Although heifers don't have to be big to be profitable.

Yup. I find it's "worse" for bulls. I can sell frame 6-7 bulls all day long, but trying to sell a 5 frame bull is like pulling teeth.

 

[Stocker Steve]

What you are saying oldtimer makes a lot of sense. However attending sales all year long at the largest Angus breeders, I find that the top selling group of females are also the largest females. On one hand we say that we should be breeding for a moderate female and then the market is demanding a larger female. Makes no sense.

My approach is to make money off of irrational buyers by retaining the large good doing calves - - then selling the biggest ones as bred heifers for the top price and keeping the rest. :banana: The effect of this is I usually sell anything with some continental in the woodpile, and retain the wf crosses.

Seems like most folks pay by the pound for black bred heifers. Used to be about $1/pound. So I would sell $1100 heifers and retain $900 heifers. :cboy:

 

[TSR]

HomePlaceAngus I agree with you 100%. At the angus sales I have attended this year the top selling heifers were always the largest. Some think breeding for moderate size female would be better, but many producers today seem to think that bigger is better. They must know if you retain heifers with heavy weaning weights they will be the easiest and cheapest to feed out for a target weight for breeding and calving. Although heifers don't have to be big to be profitable.

Yup. I find it's "worse" for bulls. I can sell frame 6-7 bulls all day long, but trying to sell a 5 frame bull is like pulling teeth.

Amen!

 

[Chris H]

I was hoping this post was about developing replacement heifers, not selecting them. It's still a good message, but I'd like to study more about developing heifers.
Last year, we cut back drastically on the amount of grain fed to the replacement heifers. The hay was poor quality, so they needed some grain. As the grass came on, they came off the grain. And now, we've got the best set of coming 2 year olds we've ever had.
This year, the weaned heifers are getting 1/2 % of their body weight in grain, and a really nice fescue field. We've got really good hay this year, and as the fescue gets low, they'll be switched over to hay.
My goal is to have them gain 1.5 lbs/day to hit a goal weight of 800 lbs at breeding time, and I think they can do it on this ration.

How do others here feed their replacements?

 

[dun]

We turn them out with the bred cow herd. If the hay really sucks we'll use protein tubs late in the winter. Otherwise they just all get stockpiled fescue and hay when the stockpile is gone. We breed in May-June and they're all well grown out by then, mostly because of the grass from late March early April on. They only get grain for 45 days or so right at weaning and that's it.

 

[Stocker Steve]

Grass in the summer, hay in the winter, salt all the time. I sell unweaned but bunk broke calves so they do get some screenings in the fall.
I weighed some up some weaned heifers a couple years ago. They only did 1/2 pound per day on very good bale grazing during a MN winter but looked good... Thus I think leaving them on the cow the first winter is my best feeding system to provide a little more energy.
Most of them do really do well when they go back to grass, and since I do not bred until August they have 3 months to pack on about 150#. At this point they have grown apart some, so I think a minium August pelvis area measurment would be a wise thing for me to improve uniformity. (Opps - - selection stuff again.)
Lots of factors on compensatory gain. Seems like they need to keep gaining at a low level and then you can get back 50 to 70% of what you missed during the winter. Any tips here on compensatory gain?

 

[ABrauny]

Grass in the summer, hay in the winter, salt all the time. I sell unweaned but bunk broke calves so they do get some screenings in the fall.
I weighed some up some weaned heifers a couple years ago. They only did 1/2 pound per day on very good bale grazing during a MN winter but looked good... Thus I think leaving them on the cow the first winter is my best feeding system to provide a little more energy.
Most of them do really do well when they go back to grass, and since I do not bred until August they have 3 months to pack on about 150#. At this point they have grown apart some, so I think a minium August pelvis area measurment would be a wise thing for me to improve uniformity. (Opps - - selection stuff again.)
Lots of factors on compensatory gain. Seems like they need to keep gaining at a low level and then you can get back 50 to 70% of what you missed during the winter. Any tips here on compensatory gain?

I know you can increase your feed efficiency by implementing compensatory gain. I forget by how much though read an article on developing replacement heifers from either OK St. or Missouri or Iowa St. they should say something about it.

 

[Galloways1]

all they can eat grass / slough hay. If we have a week of -20 degree weather, some alfalfa. Heifers are right around that 60% of mature weight at grass time, 600-700 lbs.