The "when to breed" conundrum

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The Heifer Breeding Conundrum: When to Breed – 12, 15, 18, or 24 Months?

As a stud or commercial breeder, the question of when to breed heifers is a common challenge. In South Africa, as in much of the world, most farmers run a single breeding season. However, there are those who manage two seasons, and some who opt to leave bulls with the herd year-round. For stud breeders, having defined breeding seasons is almost a necessity unless working within a highly intensive system.

Each breeding season presents its own set of challenges, one of the most critical being when to breed heifers. If you operate a single breeding season, you generally have two options: breeding at 12-15 months or waiting until 24-27 months. For those with two breeding seasons, the window opens from 12 to 24 months.

In South Africa, the conundrum often revolves around the genetics of early versus late maturation. When breeding consistently at 12-15 months, you're naturally selecting for early-maturing genetics. However, if breeding occurs at 24-27 months, it becomes harder to distinguish between early and late-maturing traits. While this may not pose a significant issue within your own herd or in herds that follow the same breeding season, it can become a problem when genetics are traded between herds with different breeding schedules.

Bulls, for example, should theoretically perform similarly regardless of the season they're bred in. However, they might end up at a ranch with a different breeding season, leading to mismatched performance expectations their heifer progeny when it comes time to mate them.

In the USA, where much of the country follows a single breeding season and heifers are often bred at 12 months, this may not be as big of a concern. But in regions further south with harsher climates, early breeding may not be feasible.

I'd be interested to hear your thoughts on the pros and cons of different breeding ages, and how, perhaps unintentionally, we might be influencing genetics through our breeding choices.

Regards
D
 
We want March calves, so that says June breeding and puts heifers at 14-15 months. June is typically 30-45 days after grass has come on and we are nearing summer solstice. We raise registered Angus and March is usually after the worst cold snaps, but we are prone to blizzards from mid-March through mid-April. Many of the seedstock guys around here calves in January-February, but they run cows through calving barns and we try to calve on pasture as much as possible. I don't want to have to feed lactating cows for another 30-45 days, March is where we settled to have yearling bulls mature enough to sell in March-April and go to work by May-June.
 
The Heifer Breeding Conundrum: When to Breed – 12, 15, 18, or 24 Months?

As a stud or commercial breeder, the question of when to breed heifers is a common challenge. In South Africa, as in much of the world, most farmers run a single breeding season. However, there are those who manage two seasons, and some who opt to leave bulls with the herd year-round. For stud breeders, having defined breeding seasons is almost a necessity unless working within a highly intensive system.

Each breeding season presents its own set of challenges, one of the most critical being when to breed heifers. If you operate a single breeding season, you generally have two options: breeding at 12-15 months or waiting until 24-27 months. For those with two breeding seasons, the window opens from 12 to 24 months.

In South Africa, the conundrum often revolves around the genetics of early versus late maturation. When breeding consistently at 12-15 months, you're naturally selecting for early-maturing genetics. However, if breeding occurs at 24-27 months, it becomes harder to distinguish between early and late-maturing traits. While this may not pose a significant issue within your own herd or in herds that follow the same breeding season, it can become a problem when genetics are traded between herds with different breeding schedules.

Bulls, for example, should theoretically perform similarly regardless of the season they're bred in. However, they might end up at a ranch with a different breeding season, leading to mismatched performance expectations their heifer progeny when it comes time to mate them.

In the USA, where much of the country follows a single breeding season and heifers are often bred at 12 months, this may not be as big of a concern. But in regions further south with harsher climates, early breeding may not be feasible.

I'd be interested to hear your thoughts on the pros and cons of different breeding ages, and how, perhaps unintentionally, we might be influencing genetics through our breeding choices.

Regards
D

Selling replacement heifers we were selling breeders. So that means we were doing AI at 15 months and then a cleanup bull. We expected better prices in private sales for our early breeders and the late breeders went to the sale barn.
 
We want March calves, so that says June breeding and puts heifers at 14-15 months. June is typically 30-45 days after grass has come on and we are nearing summer solstice. We raise registered Angus and March is usually after the worst cold snaps, but we are prone to blizzards from mid-March through mid-April. Many of the seedstock guys around here calves in January-February, but they run cows through calving barns and we try to calve on pasture as much as possible. I don't want to have to feed lactating cows for another 30-45 days, March is where we settled to have yearling bulls mature enough to sell in March-April and go to work by May-June.
"I appreciate the feedback about calving on grass—it's a great way to save on feed, and it certainly spares you the hassle of barn calving. I still have nightmares about those cold, muddy nights in the calving pens in Kansas. However, you've highlighted another key difference between the US and South Africa: here in SA, it's rare to find a bull at auction that's younger than two years old, and they're often closer to three."
 
I have been moving my calving season earlier from January - February to November - January. Now that I am where I want to be, I will start breeding heifers 13 - 15 months with the goal of calving heifers 3 -4 weeks before cows start to give them a longer recovery period to start cycling for next gestation.
 
"I appreciate the feedback about calving on grass—it's a great way to save on feed, and it certainly spares you the hassle of barn calving. I still have nightmares about those cold, muddy nights in the calving pens in Kansas. However, you've highlighted another key difference between the US and South Africa: here in SA, it's rare to find a bull at auction that's younger than two years old, and they're often closer to three."
We don't calve on green grass. It's still mostly dormant in March, but we try to stockpile our calving pastures so there is some cover. Wind and 20*F can be tough if there is no cover. March can be 70* or 0* so some years are easy and some not at all. With decent cover, 95% of calves can get up and nurse right away. We watch them very close and do haul a calf in to warm up when needed.
 
We don't calve on green grass. It's still mostly dormant in March, but we try to stockpile our calving pastures so there is some cover. Wind and 20*F can be tough if there is no cover. March can be 70* or 0* so some years are easy and some not at all. With decent cover, 95% of calves can get up and nurse right away. We watch them very close and do haul a calf in to warm up when needed.
Thanks for the clarification; I understand better now. Every region has its challenges, whether it's the cold of the northern US or the arid deserts of South Africa. As farmers, we adapt to the circumstances we're given and make the most of the resources available to us.
 
Cows go out to range here in April. The calves need to be branded before that happens so everyone breeds for February March calves. Some of the individual cows wont be seen again until November or December. If a slick calf gets separated from the cow who does it belong to? It may come back to you but it might not. Just last week I had a calf show up by its self 15 miles from here. If that calf hadn't been branded I wouldn't have got it back.
 
My window is June 1- Aug 31 : Nov 1. - Jan 31 . We like to have the main herd to calve Mar April, early May and a lesser number calving Aug, September. This is how we use to do it . Now we leave the bulls in year round which is not ideal but we have no place to keep the bulls . The way we use to do it you have a uniform calf crop . Not so much now . We breed our heifers to calve at 24 months now . We use to calve at 28 months. . First heifers we kept were a little smaller made . After improving our genetics our girls are a lot bigger .
 
We have 2 calving seasons here. Spring calving usually starts in late Feb/early March... 60-90 days. So bulls go in end of May... through mid-late August... Usually all are out by 1st of Sept. We start moving cow/calf pairs out to grass in late April... depends on the year and growth. Because we rent quite a few smaller pastures we can take a group to one place and the calves will all be more uniform, and the bulls might go in there 2-3 weeks earlier than the latest calving group.

Fall calving begins by the first of Sept and we try to be done by the first of Dec now. So bulls go in mid-Nov and out by first of Feb. The big thing for us is we buy some cows and they do not always fit the pattern... If they do a good job of raising their calf, then they will get put in with the group we want more to calve in... some of that is dependent on culling reasons...

Also at a couple places, we do not have facilities to catch them up, so sometimes the bulls go there and stay until we bring them home from pasture for winter feeding... and one place we rotational graze but the person that set it up didn't know what they were doing, so there is no way to go from the back pasture to the front where we can get them in, without going through all the other pastures, so we have to graze accordingly. It is a pain in the neck and the bull stays there the whole season.

I prefer to calve heifers in the spring, so some are older when they get bred. Preference is for them to be 27 + months when they calve, so a little older than many like. We find that ours are more mature, and do a better job of mothering their calves with a little more age on them... and they seem to last longer in the herd. We also do not push growth when younger and once past the weaning stage of 450-550 lbs, when we feed some grain on top of some silage for a couple of months, they do not get fed much grain. We have alot of 10-14 year old cows in the herd calving.. and if they do a good job and milk well enough that they wean a calf that is in the average size range, and they breed back; then they get to stay. We do not cull strictly for age... in fact some of our heifers over the years have been from "old cows" that we have bought bred; then raised up. Used to be we could buy some of these old bred cows for little over pound price... if they are that old, then usually they have done a pretty decent job over the years for someone or they wouldn't have stayed in their herd that long. Lately these cows have gotten higher and higher priced because younger bred cows and cow/calf pairs are just getting extremely high priced.
I will calve out some heifers in the fall if they are getting up in age when bred. But I like to calve them early in the fall, Aug/Sept so the calves have some size when winter hits. Our winters here have gotten so hard to figure out. We seem to get more of this cold rain and sleet weather, rather good clean cold snow like we used to have; and it is hard on all of them so don't want small baby calves then. Try to not have calves born from Mid Dec to Mid Feb .... and not in June/July Aug for the most part. We are too busy with making hay and such to want to take the time to calve out cows.
 
I used to calve april - june but got tired of dealing with calves in 3 feet of snow and 3 feet of mud.

3 years ago I switched over to calving the 2nd week of August thru September. Started breaking down into smaller groups and synchronizing cows for the bulls to shorten the calving window. This year I was done calving in 32 days. Tight calving window has yielded very uniform groups that have been selling really well.
 
How do you market your calves in South Africa? And do you have a market for cow bred to calve out of season?
Most of our calves are sold to feedlots at around 7 months of age, typically weighing between 400 and 500 lbs. There's a niche market for bred animals that calve out of season, catering to producers who run two breeding seasons and simply roll those cows into the next cycle. However, in regions with tougher conditions, it can be challenging to sell these animals quickly. Currently, our cattle industry is under pressure, with slow movement of livestock and prices well below what they should be.
 
A lesson that I learnt from Johann Zietsman is that you can't judge a heifer until she has weaned her first calf. One of my pet peeves of heifer selection is saving the biggest heifers that results in big inefficient cows. What I do is save all the registered heifers that are sound and then feeding them with a goal of getting two thirds of them bred as yearlings. I just leave the bull with the cows for most of the year figuring a late calf is better than no calf. One thing I had good luck with a couple of years ago was doing a putting in CIDRs for seven days before turning the bull out.
 
My heifers are pelvic measured at 11 months when they get their BANGS, turned out with the bull at 15 months, so should calve at 24+ months. I start calving end of February and while I leave the bulls in for 90 days, the majority calve within 45. Yup, Kansas climate can still be brutal then, but it makes more sense (in my situation) to calve while I'm still feeding bales, and they have more than adequate protection from the elements. Then they can start grazing on fresh, green grass.

You mentioned muddy nights in calving pens in Kansas. I calve out my heifers at the barn (and I'll bring down a cow if I suspect twins or anticipate any problems) but they have a ton of bedding in the barn that is regularly scraped/replaced. And I kick 'em out with the main herd, generally after a couple days.
 
My heifers are pelvic measured at 11 months when they get their BANGS, turned out with the bull at 15 months, so should calve at 24+ months. I start calving end of February and while I leave the bulls in for 90 days, the majority calve within 45. Yup, Kansas climate can still be brutal then, but it makes more sense (in my situation) to calve while I'm still feeding bales, and they have more than adequate protection from the elements. Then they can start grazing on fresh, green grass.

You mentioned muddy nights in calving pens in Kansas. I calve out my heifers at the barn (and I'll bring down a cow if I suspect twins or anticipate any problems) but they have a ton of bedding in the barn that is regularly scraped/replaced. And I kick 'em out with the main herd, generally after a couple days.
I had always thought that Wyoming had the corner when it came to wind until I was down in Iola for my sons graduation in 2018. It never stopped blowing while I was there. I have had some early calves that decided January was a good time of year to come into the world, but at least there was no wind. Although here Riverton we do need some wind to blow out the cold.
 
I had always thought that Wyoming had the corner when it came to wind until... I have had some early calves that decided January was a good time of year to come into the world, but at least there was no wind. Although here Riverton we do need some wind to blow out the cold.
I drove across Wyoming, Evanston, Rawlins, Casper, Newcastle, a little over a week ago and I've never seen it so devoid of wind. None of the many windmills were turning. Never seen it so quiet.
 
I drove across Wyoming, Evanston, Rawlins, Casper, Newcastle, a little over a week ago and I've never seen it so devoid of wind. None of the many windmills were turning. Never seen it so quiet.
Lately when it does blow something catches fire and boom -- 30,000 acres go up in smoke. We could use 6" of wet heavy snow.
 
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