Using body condition scoring for beef cows
Beef cattle producers know that a cow's body condition at the time of calving will affect the health of her calf and her ability to breed back in a timely manner. A Kansas State University animal scientist encourages producers to use a body condition score system to determine their cows' condition.
"A body condition score on a beef cow is the closest thing we have to determining her nutritional status at a glance," said Chris Reinhardt, livestock specialist with K-State Research and Extension. "But scoring cows properly and really benefitting from this tool requires more effort and observation than simply looking and thinking, 'they look a little thin.'"
The reason for talking about BCS now is that there is still time to adjust the nutrient supply to get the cows into the target BCS by calving time, Reinhardt said.
To evaluate an individual cow, he said, look at her topline, brisket, ribs, flank, round, and tail head. A borderline thin cow (BCS = 4) will clearly show three to four ribs first thing in the morning, will have no obvious fat depots in the brisket or tailhead, and the individual vertebrae along the topline will be visible. The cow still shows some muscle through the round, and she may appear "healthy but thin."
In a borderline fleshy cow (BCS = 6) the ribs and vertebrae will not be obvious, as they are covered by fat. The muscling through the round will be plump and full, but muscle definition is still apparent, and there will be small but noticeable fat deposits behind the shoulder, in the flank, brisket, and around the tail head.
The "ideal" or "target" BCS for cows at the time of calving is the BCS = 5, Reinhardt said. This cow will show the last one to two ribs first thing in the morning before feeding and have good fullness of muscle in the round with definite muscle definition. In addition, the spine will be apparent, but individual vertebrae will not be discernable, and with no obvious fat deposits behind the shoulder or around the tail head.
"We would say this cow has a good bloom," he added.
A change in BCS (from BCS 4 to 5, for example) requires the addition of 75 to 100 pounds of live body weight, depending on the mature size or frame size of the cows, the livestock specialist said.
"If you're two months from the start of calving and would like to add 0.5 to 1.0 BCS, you'll need to feed the cows for maintenance, the last one-third of gestation, and an additional 1.0 to 1.5 pounds per day of gain. This means increasing the amount of good quality hay as well as the amount of supplement."
Reinhardt said that thin cows (BCS 4 or below) can be separated off and fed at a higher plane of nutrition.
"The argument can be made that this creates 'welfare cows.' However, good record-keeping will indicate whether these cows are perennial 'hard-keepers' or if they are simply too young or too old to compete with the mature cows," he said. "If they're too young, another year of maturity should cure this; if they're too old, you may consider culling them after weaning time. The key here is that good record keeping allows you to cull intentionally based on productivity, not based on lack of observation and management."
Cows at a BCS 5 at the time of calving should provide adequate colostrum and nutrition for their calf and breed back in a timely fashion, Reinhardt said. Cows that calve below a BCS 5 will delay their return to estrus and breed back late. If these cows do not maintain a 365-day calving cycle, they could, after one to two late breedings, effectively cull themselves due to being open at pregnancy checking time.
"Young cows are especially susceptible to this because they are gestating a calf, nursing a calf and still growing frame and muscle themselves," he said. "Unfortunately, young cows are the future of your herd and possibly your most progressive genetics. Hopefully these cows aren't culled simply for lack of nutrients."
Reinhardt encourages producers to take time to critically evaluate the nutrient status of their cow herds this winter, and to use the body scoring system to manage the fertility and health of their herds going into next spring. "That way, you give yourself full control over the genetics of your herd for years to come," he said.
Keeping track of an individual cow's condition using the body condition scoring system may be simple enough, but what about a whole herd?
"Body condition scoring the herd is a simple process, and can be done on a large paper tablet," said Reinhardt.
"Make columns for BCS 3, 4, 5, and 6 and as you pass through the herd first thing in the morning, make a tick mark for each cow in each of the columns. Multiply the number of 3s by 3, the 4s by 4, etc., add up the total score and divide by the total number of tick marks. This gives you an average BCS for the herd."
More important than the average is how many cows you've got in the critical scores of 3 and 4, he said. Fours can be easily fed into the 5 range, but 3s could potentially not cycle in time to stay in the herd. If 3s can be fed into the 4 range, they'll have a chance to breed, albeit late during the normal breeding season.