A summer of excessive moisture and good grass growth followed by record-high temperatures and record-low precipitation this winter provided many Northern Plains cattle producers with the opportunity to extend their grazing season well beyond normal.

Although producers currently grazing cows are most likely saving money by not dipping into harvested or purchased hay reserves, cow stage of gestation and coincident nutrient requirements must be considered to determine whether cows are getting the nutrients they need from midwinter grasses. These cows’ nutrient requirements are changing as they progress into the third trimester of pregnancy.

Depending on their calving season, many of the cattle on pastures are experiencing this requirement increase. However, the protein of forages standing at this point is very low (probably no more than 4-5%). Cows during the third trimester should be eating feed with around 8% protein.

In addition to protein percentage, producers need to keep in mind the physical form of the standing forages. As we progress into winter, the pasture grasses are more susceptible to being knocked over by cattle or weighted down by snow and wind. Add this to the fact that winter grasses are less palatable compared with earlier in the year, and it becomes difficult for cattle to consume the amount of forage they need.

The mineral and vitamin content of standing forages likely is below requirements as well. Minerals at this stage largely are needed to develop a calf’s immune system both through nutrients circulating through the cow and from nutrients that will be available for colostrum and milk production once the calf is born. Not having proper minerals now could be a big issue for calf health in a few months. Not meeting cattle’s nutrient requirements also can affect fetal programming, although the impact isn’t necessarily seen immediately.

Rick Funston, University of Nebraska-Lincoln Extension beef reproductive physiologist, has conducted considerable research on the impact of protein supplementation during late gestation on the health and performance of the offspring. Funston found that calves born from cows fed supplements during late gestation had better growth rates, a greater percentage of heifers became pregnant during their first breeding season, and calves put into feedlots had greater feedlot performance. We’re talking lifetime productivity, and it’s not something that can be seen in the cows today but can have big impacts on herds into the future.

Producers who have cattle in late gestation should provide their cattle with some type of protein and energy supplementation, such as lick tubs, range cubes or distillers grains. Free-choice alfalfa hay delivered to cows in addition to grazing also will provide additional protein. Monitor body condition very closely and ensure the proper delivery of vitamin/mineral supplements to cows. Pre-calving losses in body condition set cows up for issues after calving. Metabolic conditions, retained placenta and delayed rebreeding are things that I would be concerned with if cows came through the summer on great grass but then lost a lot of condition just prior to calving.