By Dr. Rachel Endecott, Extension Beef Cattle Specialist, Montana State University
It’s finally starting to feel a bit like fall, and with that come chores like weaning, shipping, and pregnancy checking. While those cows are in the pen for fall work, it might be worth your while to evaluate their body condition.
Body condition scores describe relative fatness of a cowherd using a 9-point system, where 1 is “emaciated” and 9 is “obese”. The main components of body condition scoring are visible bone structure, muscling, and fat cover. A body condition score 1 cow has shoulders, ribs, backbone, hooks, and pins that are sharp to the touch and easily visible. She would exhibit no evidence of fat or muscling. In contrast, the bone structure of a body condition score 9 cow is not seen or easily felt and her tailhead is buried in fat. My theory is that most body condition score 9 cows have names, not numbers! Happily, neither body condition score 1 or 9 cows are common sights in Montana beef cattle herds.
Most industry recommendations suggest that mature cows be in condition score 5 at calving and that first-calf heifers be in condition score 6 for optimal reproductive performance and colostrum production. Characteristics of a body condition score 5 cow include that her 12th and 13th ribs are only visible if she is shrunk, and she has visible muscling and some fat on each side of her tailhead. On the other hand, the ribs of a body condition score 6 cow are fully covered and not visible, and she has noticeable springiness over her foreribs and tailhead.
Post-weaning is a great time to improve condition of thin cows because it coincides with their lowest nutrient requirements of their production cycle. This phenomenon can often be observed when cows graze dormant forage pastures post-weaning and gain body condition going into the winter, and shows that even in late lactation, the production of milk requires a large proportion of nutrients. Energy requirements decrease nearly 25% when a cow transitions from late lactation to a dry cow in mid-gestation, and protein requirements decrease by nearly a third from pre-weaning to post-weaning.
Three important times of the year to take a critical look at body condition would be at weaning/preg check, the start of the third trimester, and calving. Keep in mind that as time passes between weaning and calving, the opportunity to take advantage of lower nutrient requirements of the cow slips away. Post-weaning is usually the best time to put weight on thin cows in an economical and efficient manner.