COLBY – The old tractor still runs, but because the fuel gauge is busted, you have to keep checking to make sure it has enough fuel to continue working. And whether you realize it or not, your cows function similarly to that old tractor.
“Body condition scoring is looking into a cow’s gas tank to see how much energy reserve she has,” said Sandy Johnson, beef cattle specialist for K-State Research and Extension. “We need an idea of where she’s at as we manage her condition in relation to the quality of our forages.”
A body condition score, or BCS, in cattle is a reflection of how well a cow is, or has been, meeting her nutritional requirements. Producers must provide that adequate nutrition to their cow herd. If a cow is not getting her required nutrients, the producer can’t expect her to do her job well, Johnson said.
Producers should score individual cows from 1 to 9, with 1 being thin and 9 being over-conditioned. A score of 5 or 6 at the time of calving is recommended to achieve timely rebreeding.
Johnson said beef producers should regularly determine the average BCS of their herd. Now is a good time in the production season, when cows are either bred for spring calving or have fall calves by side, to score the herd and prepare for management through the remainder of fall and into the winter.
“Intentionally writing down and tracking (body condition) will help you know what’s going on in your herd and help you plan for known changes in your cows’ nutritional requirements,” she said.
Sometimes it’s difficult for producers to see body condition changes occurring in the herd, especially if they see the cows every day, she added. Producers should simply take a few moments to score the cows while they’re checking them. An easy way is to write down the numbers 1 through 9 and place a tally mark by the corresponding score for each cow. Writing down the scores is important, along with the date, as it helps keep track of any changes over time.
“It doesn’t matter if you have a large group of cows and don’t score them all,” Johnson said. “If you score 20 to 30 percent, you’re probably going to have a sense of the herd average body condition score.”
How often should you score?
Johnson recommends body condition scoring at several key times in the production year: weaning, 90 days prior to calving, calving and the start of the breeding season. These key times are when the cows’ nutritional changes occur. Scoring every month or two during the grazing season also is useful.
As an example, 90 days prior to calving is usually when a cow needs more energy to meet the increased demands for her unborn calf, she said. At calving, lactation will require an additional increase in energy. Producers should score their herd at weaning so there is ample time to change cow condition prior to calving, if needed.
Scoring at these various points throughout the year can help producers evaluate the effectiveness of their pre-breeding and pre-calving nutrition programs.
“As our summers have gone here, with lots of rain to no rain to somewhere in between, monitoring (body condition) would certainly give you a good sense of what’s going on with your grass, what the quality and quantity is as we go later into the grazing season,” she said. “This could be helpful so we don’t take too much condition off of that cow.”
“So that cows can rebreed in a timely fashion, don’t take more condition off the cow than you have the time and feed resources to put back on by calving time,” she continued. “A cow needs to gain more than 100 pounds during the last trimester to account for fetal growth. If she doesn’t, she in effect loses body condition.”
What does an optimum condition cow look like?
This time of year a cow will still have a slick hair coat, Johnson said, which makes it an easy time to score her.
“As we look at her topline, it would appear smooth,” she described. “We wouldn’t see any of her spinous processes. When she’s not loaded up on water or feed, seeing her last two ribs is still acceptable in a BCS 5 cow. She will not have any build up of fat around her hooks and pins, or no fat around tail head. Essentially, her brisket is going to be tight with no evidence of excess fat. She would have no muscle atrophy, which we would see on a BCS 3 or lower cow that’s beginning to use muscle for energy. So, whatever muscle she has, a BCS 5 cow is showing her full amount.”
If cows are lower than a target score of 5 at calving, they will generally have a longer than normal post-partum interval, meaning they will take more time to rebreed, and the next calf will be younger and lighter when it is weaned, Johnson said. Managing body condition is one of the things producers can use to maintain or even shorten that post-partum interval.
“As we look at a 2-year-old, we might want to have her in a little better body condition,” she said. “She’s lactating, she’s growing and still trying to maintain her body, and so our typical feed resources might come a little shy of what she needs. She’s typically going to lose a little condition as she’s lactating. That BCS 6 gives us cushion to get her rebred in a timely fashion.”
Where can I learn more?
Johnson said there are numerous reliable resources online with images and charts to help producers properly BCS their cows. An example of how to figure BCS herd averages is available in the latest K-State Beef Tips newsletter (http://www.asi.k-state.edu/about/newsletters/Sept2014BT.pdf).
Contact your local extension agent for a variety of resources for body condition scoring and for help in properly scoring your herd. Johnson said you also can practice scoring cows at your local sale barn, where more variety and differences in cows is likely available.