What happens prior to and during calving can mean the difference between a good year and a not-so-good year, and it directly affects next year’s bottom line, too. That’s reason enough to make sure you are set up for success. Here are several key factors to consider before the first calf hits the ground.
The right BCS
No matter when or where she is calving, the dam’s condition and plane of nutrition are probably the most important indicators of a good outcome for a calf. David Genho, cattle manager at Deseret Ranch in St. Cloud, Fla., where they start calving in December, calls cow condition his top priority. “If that’s right, everything else will take care of itself,” he says. “We start measuring body condition in October and measure every two weeks. Our target is a bodycondition score (BCS) of 5.” Genho’s major goal is minimizing calving difficulty, and with 42,000 cows on the ranch, that’s a priority.
His experience aligns with the research on BCS and dystocia. “There’s a common belief that if you get cows in good condition, you’re going to increase birthweight, which you do do a little bit, but you won’t increase calving difficulty,” says Cliff Lamb, professor and assistant director of the North Florida Research and Education Center at the University of Florida. “If cows are in a 5 or 6, they are not going to have any more diffi culty calving than thinner cows.”
What the thinner cows will have, however, are less vigorous calves and less effective colostrum. “For the cows in good condition, the immunity in their colostrum is greater. There are more immune factors in it,” Lamb says.
Tom Troxel, professor and associate department head of animal science at the University of Arkansas, likes to aim for a BCS of 6 during the last third of pregnancy, when the calf does the majority of its growing. “It’s been my observation that when cows calve, they lose one BCS,” Troxel says. “I’d rather have cows, when they calve, go from a 6 to a 5 than from a 5 to a 4.”
Research has shown maintaining a good pre-calving BCS matters for rebreeding, too, he adds. “Cows that calve in poor BCS take a lot longer to rebreed. Next year that cow will calve later, and her calf will be younger and lighter at weaning.”
Clean calving pastures
Lamb’s research station runs a 300-head cow-calf operation where clean calving pastures are a priority. “Cows calve in a pasture, and every two weeks we move cows that haven’t calved to new pastures that are naive,” Lamb says. “Making sure pastures are clean is important. Not having cows in the pastures you’re going to calve in for a period of time, leaving them fallow, probably does more good than anything for the health of the calves.” This is an important principle of the Sandhills Calving System (see sidebar).
For those who calve indoors, the principle of getting immunologically vulnerable calves to uncontaminated areas remains, even in cold climates. “I used to run a research center in Minnesota,” Lamb says. “We got cows to calve in a bedded area, and once the calves were up, getting them out where they could run around, away from the closed-in area where the bacteria and the parasites might be, those animals tended to do so much better.”
That’s not to say that environmental conditions are not a concern. Especially if conditions are both cold and damp, the threats to the calves must be weighed against immunological challenges. “If people are calving in pasture, mud is an enemy,” says North Dakota State University animal sciences department head Greg Lardy. “You end up with calves that are less thrifty. It’s a recipe for bacterial growth, and the calf will spend more energy trying to stay warm.” Wind can also pose a threat, he says, so pastures should have a protected area where they escape it.
Colostrum ready to go
To be able to overcome all the health challenges it will face, a calf needs colostrum, and the sooner, the better. Ideally, that would be 1 quart within the fi rst six hours of birth and 2 to 3 quarts within the first 12 hours. “Colostrum antibodies are larger antibodies,” Lardy explains. “The gut starts to close 12 hours after birth. They’ll still have some absorption after that but not as much.” By 36 hours after birth, the calf will be able to absorb only 7 percent of colostrum’s disease-fighting antibodies.
Colostrum from the dam is best, but if that’s not possible, there are other options. “If the cow doesn’t produce enough, the second choice is to use colostrum from another cow. You can collect it from mature cows, maybe if a calf dies at birth. You can freeze it in serving sizes of 1 to 2 quarts per container,” Troxel says. Thaw it in warm water or a microwave at half power, stirring or moving every few minutes, to 104° F to 110° F. Don’t overheat or refreeze it once thawed.
Use caution with colostrum from outside herds, which could be a source of disease, Lardy says. Artificial colostrums can work as a third option. “Spend the money on a good-quality product,” he says. “You get what you pay for in the amount of antibodies.”
Parasites controlled, equipment ready
Parasites take energy reserves from cows and should be a year-round focus in some regions. Genho deworms his calves in spring and again in the fall as calving season approaches. “Parasite control is insurance against non-productive calves,” Lamb says. “If you don’t concentrate on parasites, you’ll have thin cows, more calving problems because the cows will give up easier, calves that are not as thrifty and cows that produce colostrum with less immune factors.”
Research shows that deworming cows 30 to 45 days precalving is very beneficial, Troxel says. “Cows shed a lot of fecal eggs when they calve, so deworming cows prior to calving is helpful so baby calves don’t pick up a lot of parasites when they are born.”
As the season draws closer, it’s a good idea to make sure equipment is cleaned and working, and make a list of what you might need, and do it all early. “Take an inventory of your supplies, OB chains, disinfectants, in advance so you’re prepared,” Lardy says. “You might expect your first calves on March 1, but a few calves always come a couple of weeks early. Make sure everything is working so you’re prepared for those little babies.”
Sidebar: How the Sandhills Calving System works
While working at the University of Nebraska, David Smith (now a professor in the College of Veterinary Medicine at Mississippi State University) fielded many phone calls about scours outbreaks. Complaints tended to sound similar. Calving started fine, but after several weeks, calves started getting sick. The later a calf was born, the greater its risk of scours. The question became: How could they keep creating the conditions of the first week?
Smith and his colleagues noticed most calves that develop scours do so between seven to 15 days of age. “The first calves are exposed to a few pathogens that the moms carry in low numbers. They incubate the pathogens, even if they don’t get sick, so the next calves get exposed to the pathogens shed by those calves. It goes on and on.” Soon the environmental exposure becomes overwhelming.
The researchers’ solution was the Sandhills Calving System. Every week, cows that haven’t calved move to a clean pasture. Those that have calves stay there, and those that haven’t calved get moved a week later to another clean pasture, and so on.
One of the first ranches to try it had a long history of losing about 10 percent of its calves to scours, Smith says. “The first year of this system, no calves died. Now they don’t even treat calves for scours. They don’t need to.”
The system can be modified to different settings, always around the principles of age segregation and maintaining a clean calving environment. Jason Topp, who ranches about 150 miles northwest of Fargo, N.D., starts calving in early February. His cows calve indoors. He has a large barn and about a dozen pens in insulated buildings. “It’s not quite a Sandhills system, but every 10 to 15 days we move groups of pairs. There’s a really early calf pen for the first seven to 10 days. After that, we move them out to perimeter pens. It allows us to isolate those calves and keep them together as a group of similar age.”
Back at the University of Nebraska, they’re trying the system in confinement calving situations, finding it works there, too. “Even when there’s not a lot of square footage per cow, the system works,” Smith says.