It’s time to get ready for spring calving, according to Dr. Tom Troxel, University of Arkansas professor of animal science. “This is a time for getting your cows a good, clean pasture,” Troxel told Ozarks Farm & Neighbor, adding it’s also a good idea to deworm your cows 30-45 days before calving. “It’s been shown that when cows calve, they shed a lot of internal parasites,” Troxel said. “If you deworm your cows prior to calving, that helps reduce the internal parasite load of your calves.”
Troxel recommended producers use the opportunity to prepare all the tools they’ll need, like calving chains, lubricant, OB sleeves, and colostrum in the refrigerator. Also, make sure you’ve got the phone number of your veterinarian handy so that when you have an emergency, you’re ready to call.
Some pregnant heifers may actually calve in early winter, and it’s important to watch pregnant heifers carefully to be able to assist them when necessary. “Sometimes you have light birth weight calves, so you have to be careful to make sure those calves will get up and nurse,” Troxel said. “Those calves may not have the energy to get up so make sure that those cows and calves pair up, and those calves get a good nursing of colostrum.” Colostrum contains the proteins and antibiotics the calf will need to fight diseases early in life; if it’s a cold, wet winter, it will be the calf’s first line of defense against a potentially fatal bout of scours.
Eldon Cole, University of Missouri Extension area livestock specialist based in Lawrence County, said grass tetany can also be an issue. “I always tell people to start thinking around the first of the year to buy a grass tetany-type mineral that has 10 percent or more actual Mg in it,” Cole told OFN. “Those problems usually occur on these spring calving cows that are heavy milkers, and may be eating a pretty good amount of lower quality feed that may be low in magnesium.”
Cole acknowledged calving season has become a moving target. He explained historically all calves were usually born before the first of June, “but as time has gone on in Southwest Missouri we discovered that sometimes these cows that were running on fescue didn’t seem to want to breed back very readily, and wouldn’t breed back until the cooler weather in the fall after the ‘hot’ fescue had done a number on them.”
Cole, a 50-year veteran of Missouri Extension, said the trend of fall calving became more noticeable the late ‘60s and early ‘70s, as many ranchers were leaving their bulls out with the cows all year long. He said, “We can get more bull power usage by having both calves in the spring and the fall, and we can lessen our bull expense per calf and spread out our marketing season.” But, he added, there are still a lot of cows that calve from mid-January up through the first of May.
Cole noted that while Extension talks about splitting up the cow herd so spring calvers and fall calvers are not running together, it doesn’t always happen that way in practice. However, it’s more economical to divide the herd so the fall calver is not getting the same feed as the spring calver that needs more feed and of higher quality. There is also the recent research that shows cows fed later in the day tend to calve more often in the daylight hours; while some people have reasons for feeding first thing in the morning – for instance, they may want to provide hay before they head to an off-farm job – Cole noted an earlier spring calving has the benefit of taking place when it’s not as cold and easier to see; also, if you have to call the veterinarian, he’d prefer to come out during the day than late at night.
