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Weighing A Change Of Calving Season

There are many factors involved when making decisions about when to calve. Whether you calve in January-February (early calving), March-April (spring), May- June or June-July (summer) or September- October (fall) often hinges on region and climate, marketing goals, feed costs and availability, breeding season considerations, constraints of management, and other factors that enter into this decision. There is no perfect time to calve, and each producer must weigh the pros and cons of each season to find what works best for his/her own situation and goals.

Dr. Jason Ahola, associate professor of beef production systems at Colorado State University says the majority of beef calves are born in early spring, such as February through April. “This calving season, to me, seems historically rooted in the need to wean calves in the fall, to put them in a feedlot to feed through winter. As corn prices and feed prices change, however, two things will probably affect this tradition. First, feedlots are starting to differentiate more between lighter and heavier calves, in terms of whether they can go straight to the feedyard or can go to grass first,” he says.

“Secondly, with increased hay prices, cow-calf operations are looking at wintering costs and many are realizing they can’t survive on what they’ve done historically,” he says, taking a harder look at negative aspects of feeding hay during the early part of lactation when cows’ nutritional needs are highest. Thus climate — and how much hay you must feed during winter — can be a major factor in when you calve.

“I teach a beef systems class here with undergraduates, and talk about matching resources to the cow herd requirements. Students typically ask questions about calving season, such as if early lactation is the highest requirement, why is this always occurring in February-April when there is no grass available? Why don’t we mirror wildlife, and calve later in the season? This is a legitimate question, but the problem has to do with logistics. In the West there are many ranchers who calve in January just because they have to get cows bred before they go to summer range,” says Ahola.

Calving on the range may be a poor management option if cows are widely scattered and can’t be checked frequently. Even if you calve at home and breed on the range, the vast areas involved require more bulls — and still not all the cows get serviced at the proper time. Calving is strung out. For many ranchers, this is not a viable plan. On allotments shared with other ranchers, it’s impossible to breed your cows to only your own bulls (for specifi goals in genetic improvement), or to selectively breed heifers to a certain bull for easy calving.

“Most grazing associations have rules on what breed or type of bulls can be turned out, and this is another constraint. This doesn’t always match what you want in your own operation,” he says.

“Beyond saving feed costs and matching cows to the environment and availability of grass, you may want to market at a time of year when few other stockmen in your area are selling cattle. Consumers eat beef every day of the year, yet two-thirds of the calves are born in a three-to four-month window. If you can take advantage of seasonality of calf price changes, this can be beneficial,” he says.

“Another thing that may be valuable is flexibility to have two calving seasons, such as fall and spring. On the negative side it strings out labour, since you may have someone checking cows twice as long (a period in spring and another in fall). But if you select for low-birth weight bulls, labour can be minimized,” says Ahola.

One advantage of two calving seasons is that you can retain more of the investment you’ve put into heifers. “For a first calver to come up open during the next year is a major loss. But if you can move her into your fall-calving herd (giving her a little more time to breed back, so she doesn’t come up open), you can keep her,” he says.

“Some people argue that you’re not selecting hard enough for fertility in this type of program,” he says. But in many instances a first calver comes up open because of management (inadequate nutrition) rather than genetics.

“Studies have shown that sustained fertility is of low heritability. Fertility is mostly driven by environment (and nutrition), unless cows have increased fertility due to heterosis. But producers need to consider this when moving a heifer or cow into a later calving season.” If she’s not as fertile as she ought to be, she may just keep moving from one season to the next one, if she can’t breed back quickly enough to stay in the calving season she started in.

One downside for later calving is that summer or fall might not work in some climates. Summer heat may be hard on baby calves because they can dehydrate so readily, and breeding during the hottest part of the year may result in lower conception rates. Fall calving in a cold climate may be as inefficient as January-February calving; you’ll have higher winter feed costs to carry lactating cows through winter.

“Some people move to the May- June calving and still wean in November, so they aren’t feeding hay to lactating cows,” he says. Summer-born calves on irrigated pasture grow more quickly than calves on dry rangelands, and will be nearly as big by November as earlier-born calves. Every producer’s situation is different, and you must figure out what might work best for your own operation.

“Colorado State University’s ranch went from February-March calving to May-June calving this year. Those summer-born calves weighed 100 pounds less than they usually would, but brought nearly $1.50 per pound because they were lightweight and because corn is so expensive right now. Buyers wanted lightweight calves to go on grass. The university ranch was able to early wean those calves. Even though they were lighter, the dollar value wasn’t much less, and hay sav- ings were tremendous. The ranch fed less than a quarter the amount of hay they fed to cows the previous year,” says Ahola.

“There are some risks in summer calving, and it’s a big decision, but the chance for calf-killer storms (late-winter storms when spring calving) almost disappears. It’s been proven that calf death loss decreases, and per cent calf crop tends to increase. Feed costs generally go down so you are less at the mercy of the volatile hay market,” he says.

Breeding season is determined by when you calve. If you calve in late spring or early summer you may be experiencing the hottest weather (August or early September) when cows are breeding. Hot temperatures can reduce fertility in bulls and cows, or result in early embryo loss in cows. This may reduce pregnancy rates.

If hot weather isn’t a factor, breeding later in the season may be a cost saver if you can share bulls with stockmen who calve and breed earlier. “As long as the bulls are trich tested and healthy, this is a way to cut costs. Most bulls work for only about 60 days of the year,” says Ahola. If you and your neighbour share bulls, they could be rested for a few weeks after their early breeding season and then be used again.

“Even if you have to increase bull-to- cow ratio a little, this could save money. With A.I., if you’re having trouble finding someone to do your A.I. when everyone else is doing it, this is a chance to utilize these technicians when they are not busy,” he says.

Sometimes it’s more difficult for a seed stock producer to change calving season than for a commercial producer. Calving for the purebred breeder may hinge on when the bulls are sold. “If someone has been coming to your place to buy yearling bulls in a spring bull sale for the past 10 years, and then you move your calving season and those bulls are only nine months old at that time, you can’t sell them that young,” he says. Just like the range user, you are locked into a certain time of year you need to calve. To calve later, you may have to sell bulls that are 18 months old or close to being two-year-olds.

“My own situation is a seed stock operation and we calve much earlier than we should (starting the end of January) in order to produce a bull that’s old enough to market in our sale. There’s no other way to do it unless you sell two-year-olds. Many two-yearolds sell for about the same price as a yearling, yet you have an additional year of feed cost. It’s hard for seed stock operations to change unless they go to a fall-and spring-calving (dual-calving season),” he says. This gives customers the option of buying bulls that are a little older than yearlings, but not yet two-year-olds. They may prefer the 18-month-old bull that can handle a few more cows and more rugged conditions than a yearling.

“The downside of calving late in the year in some regions is that quality of forage is declining. Protein level is lower as grasses dry out,” says Ahola.

“One advantage to fall calving is you then have a 400-to 500-pound calf in April, that will really bloom on grass. Some people sell calves then, but if you can keep them through part of the summer and sell them as yearlings, you can run fewer cows and make as much money,” says Ahola. This is when those calves will gain the most, on grass.

“The summer-grazing segment of our industry, versus cow-calf/feedlot/ packer is the most consistently profitable segment. It’s low cost, if you have the grass. You can kick weaned calves out as soon as the grass is ready, and gather them up at the end of summer when grass begins to decline, with maximum gain. You have some income from the gain on the yearlings, and may not have to own as many cows,” explains Ahola.

“If you live in a region with harsh winters, however, you’d have to feed fall-calving cows a lot, and have a place to bed calves and protect them from storms,” he says. Those calves are more vulnerable to pneumonia than the adult cows.

“Holding calves until yearlings has some advantages, however. If you calve in May and wean in November, you can still do that, but you’d have to carry the weaned calves through winter, dealing with them separately and feeding them separately. The benefit in calving in October-November is that calves will be on the cows through winter and the herd can be together and you don’t need a different facility or feeding system. You could wean calves the next spring right on to grass,” he says. “Successful fall calving hinges on your facilities, the winter, and your willingness to make it work.”

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