Good stockmen have always had an “eye” for body condition, but scoring methods like BCS provide a way to attach a numerical value to what you see and to record it for reference.
A BCS recorded at the proper time is a valuable item to have in your record book. It also allows you to make a conscious evaluation of each cow while there’s still time to make adjustments if needed.
Trial data is pretty dramatic in showing how BCS affects conception and pregnancy rates (Table 1).
Most data follow a curve similar to the example shown in Figure 1, so cows with body condition scores from 5.5 to 6.5 are better for conception and calving rates.
What is her score?
There are several scoring helps and teaching aids available online and in extension and breed association literature (Table 2).
While bodyweight is affected by condition, it’s not a guideline for scoring. Muscle and fat should be the indicators rather than weight, since weight is associated with frame size as well as condition. Hormones that affect reproduction are influenced by the condition and health of the cow.
Some herd managers utilize an outside person to evaluate cows. Someone who has practice in scoring cows of different body types and has scored cows in a variety of herds may provide an impartial and more accurate observation.
If you’re going to score your own cows, make sure to fight the temptation to be more forgiving to your favorite or best cows. The important thing is to understand the scoring guidelines and make it a point to do it at the right time. Then it becomes a valuable tool in management.
When is the right time to evaluate?
Body condition at calving probably has the greatest influence on the next breeding, but it’s very hard to change at that point. Cows that have just calved use extra energy to make more milk rather than to add body condition.
If you were to pick one time in the cow’s year to record a score, it should be 60 to 90 days prior to calving or at the beginning of the third trimester. Doing it then gives you time to group cows or change feed levels so the condition score is right at calving.
How to adjust BCS
What can be done if the herd is too thin? If you still have two or three months before calving, you have a good amount of time to make adjustments. There are some routine management practices that need to be considered first:
Parasites – Are internal or external parasites competing for the energy the cows are consuming? If so, now is the time to get rid of them. Several options are available to worm cows without running them through the chute.
Flies – Depending on the time of year, flies may be hurting the cows’ ability to add condition. Fly tags, sprays or feed-through products may be necessary to reduce irritation.
Forage quality – Forage may be in short supply or of low quality. Either situation will limit cows’ ability to eat enough to add condition. A check of quality can be easily done with a lab analysis and will aid in knowing how to supplement. In some cases, cattle should be moved to better grazing or put into a drylot for feeding.
- Herd health – Now would also be the time to treat any health problems before getting closer to calving. Foot rot is a common problem that can cause severe weight loss. Fescue with high levels of endophyte can inhibit weight gain or cows’ ability to add body condition.
The next task is to decide how to add enough energy and other nutrients to allow for the gain needed.
It takes an addition of approximately 75 pounds to change a full BCS point. So if you have scored your cattle an average of 5.0 and want to move to 6.0 in 90 days, you need to add about 0.8 to 1 pound per day before calving.
The weight of the developing calf and accompanying fluids will add another pound per day, which means the cow needs to gain 1.8 to 2 pounds per day.
A pregnant 1,200-pound cow gaining 2 pounds per day requires approximately 16 megacalories (Mcals) of net energy maintenance per day (NEm per day) compared to 13 Mcals required for the same cow to maintain its condition score.
If forage contains 0.5 Mcal per pound of NEm, it would take 32 pounds of dry matter forage to provide 16 Mcals NEm. Often, a cow wouldn’t be able to consume that much dry matter every day, so Table 3 shows different ways to meet that requirement.
Poor-quality forages may be 0.4 MCal per pound or less NEm and would require more supplemental energy.
Scoring 90 days prior to calving would mean late fall for spring calvers and mid-summer for fall calvers. Weather might include heat stress and drought or cold, windy and wet conditions, depending on time of year and location.
Forage conditions can range from excellent to poor or lacking. Increasing a full condition score will normally require supplemental feeding and possibly a change in pasture or additional hay or silage.
What if my cows are too fat?
Sometimes it’s unavoidable – cows are over-conditioned. Lots of rain and fertilizer on planted forages can produce amounts of forages that are more than cows require. Since cows that have just calved are beginning to milk and are expected to breed back in the next 90 days, that’s not the time to have the cow losing body condition. Conception rates are adversely affected when cows are in a weight-loss condition at breeding.
Therefore, it’s good to use caution reducing nutrient amounts on cows close to calving. If scoring cows 90 days prior to calving, it would be possible to make some adjustments prior to calving, but caution should be used to not make large nutrient reductions until cows are safely bred.
Keeping a cow herd profitable from year to year depends on getting cows bred. A good tool in the management toolbox is body condition scoring. Planning a time to evaluate the cows and write down a score will establish a time to make management decisions.
Bringing cows to calving in the proper condition will increase your chances for a higher conception rate and more calves born next year. Body condition at the beginning of the third trimester affects breeding six months later and, consequently, the number of calves to sell a year later. Proper condition today equals profit next year.
PHOTO: Braunvieh cows graze at Wonderland Cattle in Brighton, Illinois. Their body condition scores at breeding will have a large impact on conception rates. Photo by Lynn Jaynes.
- Beef Technical Specialist
- Cargill Animal Nutrition
- Email John Marks