For cows to calve efficiently, farmers need to make sure they maintain the proper weight.
Watching weight has a whole new meaning when it comes to efficient cattle production. According to beef specialist Ron Lemenager at the Purdue University Cooperative Extension, thin cows can be economically devastating as farmers head into spring calving season.
“Spring-calving cows need to be in moderate body condition at the time of calving because it has a pretty significant effect on how quickly these cows will return to estrus after calving and, subsequently, when or if they conceive,” Lemenager says. “If cows are thin at calving, producers can expect long postpartum intervals, which means they will calve later the following season.”
Instead of having a 12-month calving interval, farmers may face 13- to 14-month intervals and ultimately lose cattle-breeding productivity.
Thin cows also tend to have lower colostrum quality, which means calves aren’t don’t receive the passive immunity they need to guard against disease, cold stress and other stress factors.
“These thin cows are going to have lower milk production, resulting in lighter weaning weights of their offspring,” Lemenager says.
Ideally, cows should have a moderate body condition score of 5 to 6 out of 9 on the body condition scoring (BCS) system for beef cows. In order to evaluate whether cows are at a healthy BCS, Lemenager recommends producers look past the winter hair coat the animals are carrying right now.
Three places on the cow are good indicators of body condition: along the top line, in the rib section and along the loin edge.
“If you can see bone structure along the top line right under the hide, the cow is probably pretty thin,” he says. “If the cow shows the 12th and 13th rib, she’s borderline. If you can see more ribs—the 10th, 11th, 12th and 13th, the cow is too thin.”
The loin edge between the 13th rib and the hooks is least affected by muscle, fill and hair.
“If a producer can see bone structure at the edge of the loin, the cow is too thin,” Lemenager says.
At this time of year, spring-calving cows are well into the last trimester of pregnancy. Because of fetal nutrient requirements, correcting low BCS can be a challenge, but it’s not impossible if farmers can strategically supplement the animals with high-quality feed.
“Producers should be looking at cows monthly and using BCS as a wake-up call,” he says. “They are a good indicator of nutrition and reproduction. If cows look to be gaining or losing BCS, producers need to evaluate and adjust rations to optimize performance and minimize expenses.”