6 tips for a tighter calving window

As black cows and their calves graze the lush, green, rolling Pennsylvania pastures at Lisnageer Farm in Coatesville, Cheryl Fairbairn closely observes the mothers and calves. Over the years, Fairbairn has developed a no-nonsense approach to managing the breeding of her 120-head purebred Angus herd. 

"The sole reason behind a tighter calving window is a uniform calf crop to sell. Having a group of calves ready for market in a similar weight range is more desirable for a feedlot or backgrounder," says Fairbairn, a cattle specialist with Pennsylvania State University Extension.

Eric Bailey, a University of Missouri Extension cattle specialist, says the increased weight of early-born calves is a benefit. He says that calves can gain two pounds a day from birth to weaning.

"You will be rewarded with heavier calves born earlier in the calving season so close together," Bailey says.

A short calving season can also improve a cow herd's reproduction productivity — giving farmers like Fairbairn a peek into each female's fertility. Females with high fertility usually will get bred first, while others — especially with lower fertility — will be bred later, which can risk the productivity of a calving season.

"When you see a female falling outside your season window, it means you must look at her genetics, environment, and fertility critically," says Fairbairn.

Fairbairn and Bailey share some tips on tightening your calving season and boosting your herd's reproductive performance.

Know Your Calving Window

In short, the average beef producer has no ideal calving window, says Bailey. Picking the right time for calves to drop on the ground depends on your farm's location and forage system.

In Missouri, Bailey is seeing many beef farmers switching their herds from spring calving to fall calving so the cows and calves can benefit from the re-growth of their pasture's cool-season grasses.

"The best thing you can do for your cows is to have them calving out on green grass," he adds.

In choosing a calving window, you should also know your calf market. For example, in Pennsylvania, producers will set their calving window from January to May, depending on that producer's goals for the calf crop. Fairbairn says that most Keystone beef producers plan to sell those spring-born calves as feeder cattle in the fall season.

At the farm that Fairbairn operates with her husband, Bill, most of the Lisnageer Angus herd is programmed for a 60-day calving window. "We strive to be done calving by the middle of April, so we can focus on other farming activities like getting into the fields to make hay," she says. "The babies are also on the ground before the summer files come."

Keep Cows, Bulls in Good Flesh

As the months in the calendar get closer to your breeding date, farmers should ensure their cow herd is fit and healthy.

"Body condition management at calving is key. We can't change a cow's body condition score between calving and weaning to maintain her," says Bailey.

Cattle should range between a body condition score (BCS) of five and six at calving. Visually, your cows should have shape to her hips and muscle tone and no fat in a tailhead — a telltale sign that the animal is over-conditioned.

"She should look fit and have shape; you barely want to see her ribs," Bailey says.

Fairbairn adds that breeding season is a bull's busiest season, so producers should invest in a breeding soundness exam to ensure he is ready to breed cows. "You don't want your bull sloppy fat, or too thin or being bad on his feet and legs, or he won't do his job," she says.  

Use Estrus Synchronization

Once you have determined your calving window, the real challenge of getting your cows and heifers can begin. For the best results with cow conception, Fairbairn and Bailey both suggest using estrus synchronization.

"You don't have to sync, but to close the window it's the easiest way," Fairbairn says.

Producers can give a shot of prostaglandin, a hormone that stimulates the cow's biology to come into heat/estrus before putting the cows out with the herd bull. Fairbairn notes that to use prostaglandin, producers must have a Veterinary Client Patient relationship (VCPR) and work with a veterinarian. Producers can give females a single shot or use a shot of prostaglandin with a tool — a vaginal CIDR (Controlled Internal Drug Release) implant.

If you are going to sync, the practice can be paired with using a bull or timed artificial insemination. If going the artificial insemination route, Bailey advises farmers to work with a technician over doing it themselves.

 "It's hard to get them bred, so use a skilled technician to avoid further human error when trying to do it yourself," he adds.

Pregnancy Checks

At 30 days or longer after breeding, producers can check to confirm pregnancy. Bailey says to expect 60-65% bred via timed artificial insemination and 88-92% pregnancy rate overall. 

Fairbairn says if females are found open, producers must make a choice. A small herd may decide to hold her over to calve in the fall or early next spring. However, the economics state that open females should be culled. 

"The only way a cow pays for her keep is if she has a calf every year," she adds.

Add a Third Bull

If you have 20 to 30 head of cows, increasing your bull power from two bulls to three could be a game changer. A bull will breed one cow for every month of age he is, and with a group of cows all coming into heat within 21 days, having an additional bull keeps you and your cows on track to meet the calving window, says Bailey. Do not expect too much from your 12 to 18 month old bull, he adds. 

Be Disciplined

Be rigid in your decisions, says Fairbairn. That means if you're breeding with a bull, make sure you pull him off the cowherd to keep your calving window in line. Don't leave him with the cows all year-round, or he will breed females with low fertility that will calve outside your calving window.

Producers should cull cows and heifers that have low fertility. Fairbairn says she knows that farmers tend to develop a favorite female in their herd over time, which isn't a total crime except when that cow's performance drops, and her calves are born outside your window.

"My best advice: don't have a favorite cow," adds Fairbairn.