On any given day all across the country, feeder calves are sold at auction, on farms, and between individuals. Many times the price received is what producers’ believe is the “worth” of calves. Worth is defined as the quality of any thing that makes it have value in money or other goods. In many cases the price received is determined by real or artificial factors. Artificial factors can be things such as hide color, perceived health, or breed beliefs that may or may not have true effects on the value or worth of a calf. Real factors can be defined as those that can be measured such as frame size or muscling. These two factors are not the only measurable traits, but are the most important when health is determined to be similar between calves.

In a study from KansasStateUniversity, the discounts applied to calves based on muscling can be dramatic. This study, conducted in 1986, 1987, and 1993, used calves with average to heavy muscling as benchmarks for price received. Steers with medium muscling characteristics were docked at $5.16/cwt. and steers deemed light muscled were docked at $19.40/cwt. These discounts when applied to 550 lb. steers amounted to losses of $28.38 and $106.70 per head. When applied across an entire calf crop, these losses could be significant. The same study also evaluated prices received as compared to frame size. Large framed animals were used as the baseline and discounts for upper medium frame, lower medium frame, and small framed calves were $0.79/cwt., $1.66/cwt., and $11.30/cwt. respectively.

A study on improving the value of feeder calves conducted by the University of Arkansas indicated similar findings as those in Kansas. Based on USDA muscle scores of 1-3, with 1’s used as a baseline, the discounts were $4.72/cwt. and $13.40/cwt. for 2’s and 3’s respectively.

Why are muscling and frame size so important? The answer lies in the final product that cattle producers are responsible for; BEEF. This is true because the main parameters used to determine price received is based on yield grade and quality grade of the carcass. Scientific study after study has reinforced the need for cow-calf producers to base genetic selections and management protocols on this fact. In order to understand the importance of these factors, one must understand that feeder calves are grouped into pens at the feedyard and slaughter date is determined by evaluating the calves and marketing when most are at acceptable quality carcass points.

Muscle has become a buzzword in the beef industry over the past few years. Packers, show judges, purebred breeders, and some consultants are promoting the virtues of muscular cattle as if muscle had just been discovered in an animal. In truth, the industry has for too long produced too many light muscled calves.

Many breed associations are now reporting EPD’s for ribeye area as if it is the only selection trait to be considered. This trait is important as another selection tool, but selecting for one trait such as muscling will lead to losses in other equally important production traits. Even though ribeye area is a good indicator of overall ribeye muscle size, it is not an absolute measure of overall muscling which is the major factor affecting lean meat yield for an animal. Packers and consumers do not want too large or too small cuts of meat. The desired ribeye area is 1.7 – 1.8 square inches per hundred weight of carcass. The target ribeye area is a range from 12 – 14 square inches. This translates to acceptable carcass weights from 675 – 825 pounds.

Light muscled calves have low cutability, produce small primal cuts, and due to these points are “worth” less than calves that have medium or heavy muscling. It is very important to remember that calves that do not have the genetic potential to produce muscle tissue cannot be developed through any nutritional or management program. Research has examined the performance and cutout differences in cattle varying in muscularity. Feeder calves representing the three USDA calf muscle scores (1-3, 1 is most muscular) and frame sizes (large, medium, and small) were fed to slaughter. Heavy muscled calves grew faster and more efficiently and had higher carcass yields than light muscled calves. In addition, a muscle/bone ratio is sometimes used by packers to determine carcass value or worth. Muscle score affects this ratio, but frame score does not. Muscle thickness has also been determined to have an effect carcass fabrication. This can have large effects on the amount of trimmed boneless beef product produced by an animal as a percentage of live weight. On a 1250 pound steer, a 1% change in trimmed boneless product can and does have a tremendous effect on the “worth” of an animal.

Table 1. Feeder Calf Grades - % Muscle

Muscle Score

Frame Size123Average

Large66.763.862.564.4

Medium 63.059.960.261.0

Small60.058.258.258.8

Average63.460.860.5

J.A.S. 62:121

Table 2. Feeder Calf Grades – Muscle/Bone Ratio

Muscle Score

Frame Size123Average

Large3.993.763.323.68

Medium 3.943.703.573.73

Small3.863.743.573.72

Average3.933.733.48

J.A.S. 62:121

Table 3. Effects of Muscle Thickness on Carcass Fabrication

Muscle Score

Item12

------% of live weight ------

Trimmed, boneless product44.741.9

------% of carcass weight ------

Trimmed, boneless product71.570.2

Adapted from J.A.S. 67:2669

So what does all this mean, and how does it affect worth?

The best way to answer the question is to evaluate some “real world” examples.

In most cases, the quality grade and the yield grade of an animal are the primary factors considered in determining price the feedlot operator receives for his product. Yield grade is a numerical figure derived by the actual meat yield of an animal. The yield grade can be from 1-5. The quality grade refers to the actual quality of the carcass from an eating standpoint. Quality grades are familiar descriptors such as select, choice, and prime.

The payments for cattle after slaughter are calculated bases on “normal” parameters with discounts for being outside the normal range. For example, on January 16, 2006 the reported prices received for carcasses was $154/cwt. ($1.54 per pound) for choice carcasses with select carcasses receiving $141/cwt., a discount of $13/cwt. Yield grades using 3.0 as a baseline showed an increase of $2/cwt. for a carcass with a 2 and a discount of $14/cwt. for a yield grade 4. Obviously, cattle that will finish with a yield grade of 2 – 2.5 and that will grade choice are the targets. How close an animal can come to these endpoints will have an effect on the price it receives as a feeder calf.

For example, a calf that is medium framed will weigh approximately 1250 lbs. at slaughter. If that calf has a dressing percentage of 63%, it would yield a carcass weight of 788 pounds. If it grades choice, and is a yield grade 2, the price received would be $154/cwt. plus a premium of $2/cwt. or $1.56 X 788 pounds for $1229.28.

On the other hand, if the animal was small framed, finished at 1000 pounds, had a dressing percentage of 60%, it would yield 600 pounds of meat. If the yield grade was 4 due to excess fat and the quality grade was select due to light muscling, the price received would be $141/cwt for select minus a discount of $14/cwt for a yield grade 4 or $1.27 X 600 pounds for a total received of $762. This is a difference of $467.28. Unfortunately this is all too common an occurrence in feedyards. Remember, a particular pen of cattle is sold when most are considered ready. This lack of uniformity has a tremendous affect on the price a feedyard owner is willing to pay for a calf.

In order to make the most from your calves, remember to think about how your calves will finish out. If they need muscling, bull selection can help. If they need size (frame score), once again genetics are the answer. Remember, every calf is born with all the genetic potential it will ever have, we can’t feed or manage it to have more than what is there the day it is born.

Assessing muscle score

When determining muscle score one must first estimate the level of fatness covering the body.

A pre-requisite of accurate muscle evaluation is the accurate appraisal of fatness. Once an animal’s fatness is known, allowance can be made visually and mentally to ensure that fatness does not hinder the evaluation of the animal’s shape.

Closely examining those areas of the body where fat is most visible or actually feeling those areas of the animals body, it is possible, with training and practice, to become extremely accurate in subjectively determining the level of subcutaneous fat.

The best places to assess muscling are those areas least influenced by fat, i.e. the hindquarter, the round and the top line.

Indicators of muscling in order of importance are:

  • thickness and roundness of the hindquarter,
  • stifle thickness and width in the twist,
  • width across the back and loin.

Forearm thickness and leg stance are useful only when differences in muscularity are large. When forearm circumference can be measured then it is the best measurement indicator of muscle score.

Figure 1. Areas of reference for assessing muscling

Figure 2. Observing cattle from behind

Observe cattle from behind to assess thickness through the lower hindquarter (stifle area). Heavily muscled stock are thickest here. They also stand with their hind legs further apart than lightly muscled stock.

There are three broad categories of shape - average, poor and good. Picking the differences when they are as simple and clear as this is not difficult (see Fig 3).

Figure 3. The three simple shape categories

Good
Wide, well-rounded topline; maximum width through stifle; has a wide stance and the stomach cannot be seen. /
Average
Not as wide or well-rounded over the topline; hip bones can be seen; has a narrow stance and the stomach is clearly visible. /
Poor
Narrower over topline, tapering through stifle; narrower stance; more prominent hip bones; stomach is more clearly visible. /

Most British-type steers would be classified as average shape. If an animal appears better than average then the assessor needs to distinguish whether this change is due to an increase in subcutaneous fat cover, or to an increase in muscle. Fatter animals generally do not exhibit the roundness or convexity which is present in more heavily muscled animals. Well-muscled, leaner cattle display clearly evident seams between the muscles of the hindquarter. Poorly-muscled cattle are thin through the stifle and are clearly widest across the hip area.

When shape differences are as clear as in figure 3, assessment is easy. However, within the normal cattle population differences in shape are far less distinctive. It is these situations which can cause confusion. To help separate animals with smaller differences a more expansive descriptive scoring system (5 scores) was developed based on the three levels as in figure 3, but expanded to include quite good muscle development (e.g. heavily muscledEuropean breed bull) and quite low muscle development (e.g. poorly muscled dairy breed cow).

Muscle Score Categories

A score from A (very heavily muscled) to E (lightly muscled) can be given based on the roundness (convexity) and thickness of the body due to muscle (see the illustrations below).

To help distinguish smaller differences between animals, and add continuity to the scoring system, the five scores can be further extended to 15 by adding plus and minus to each score (A+ to E-).



/ A. Very heavy (double) muscling
  • Extremely thick through stifle area
  • Muscle seams or grooves between muscles are evident
  • ‘Apple bummed’ – when viewed from the side, hindquarters bulge like an apple
  • Butterfly top line – loin muscles along the top of the animal are actually higher than the backbone



/ B. Heavy muscling
  • Thick stifle
  • Rounded thigh viewed from behind
  • Some convexity in hindquarter from side view
  • Flat and wide over top line – muscle is at the same height as backbone



/ C. Medium muscling
  • Flat down thigh when viewed from behind
  • Flat, tending to angular over top line



/ D. Moderate muscling
  • Narrow stance
  • Flat to convex down the thigh
  • Thin through stifle
  • Sharp, angular over the top line (except when very fat)



/ E. Light muscling
  • Dairy type – very angular
  • Sharp ‘tent topped’ over top line
  • Virtually no thickness through stifle at all
  • Stands with feet together; concave thigh

So, What is your calf worth?