Holiday Ranch
Breeder of South Poll Grass Cattle

Linear Measurements to Evaluate Heifers

PVC pipe measuring tools

With the help of my friend, JB, we recorded linear measurements on our Holiday Ranch cattle back on November 8th when all animals were worked through the chute.  We used homemade PVC pipe measuring tools adapted from those used by Gerald Fry.  Gerald is probably our country’s number one advocate for linear measuring.

The information shown here is taken directly from Gerald’s website, www.bovineengineering.com.  Please visit his website to learn more detail.

In this image, taken from JHL Beef, you can see all the places to take a measurement.  Mr. Fry’s website also shows where to properly take the measurements.

Once the measurements are recorded, then what?  How do we interpret those measurements?  Gerald Fry to the rescue!  Here is what he says about the female measurements:

TOP LINE

The top line is the total length of the animal from front of pool to back of rump.  The top line is taken from three measurements, Neck length, Body length and Rump length. These three measurements make up the total top line length.

HEART GIRTH

Heart girth is the total distance around the animal’s heart girth. The heart girth should be equal to the total top line or larger at 12 months of age. The large girth is needed for proper size of the vital organs (heart, lungs, and glands).   The closer the heart girth is to the top line, the more efficient, adaptable and vigorous the animal will be. Larger heart girth to top line is better.   Insufficient heart girth is a high indicator of structural defects, allows front feet to toe out, hooked toe, more susceptible to stress and is a high maintenance animal. They do not perform well on grass. Small heart girth is a structural defect and should not be tolerated. Reproduction suffers.

NECK LENGTH

Actual neck length minus ½ the body length. Neck should be equal to half the body or half of 2/3 top line. The neck should be 1/3 the total length. A well-balanced cow will have a neck half the length of her body. The ideal range is +.5 or -.5 inches.  If the neck is too long the cow will be very dairy and high maintenance. Easy to stress. Her daughters will have long necks. Long necks tend to over produce milk, making the maintenance high and she will be a slower breeder.  If the neck is too short the cow will be wider in the shoulders (coarse) and milk production suffers.  This is a loss of femininity and masculine features: Long necks in the female are not symbolic of femininity.

BODY LENGTH OR 2/3 TOP LINE

The 2/3 top line is composed of the rump length and back length. Distance from the middle dip in vertebrate between the shoulder blades to back of rump.   If the back is to long it affect the neck length and the animal is out of balance.  Long backs tend to be weak and will sway. Most long backs have too small a loin muscle. Long backs can cause an irregular shaped loin muscle. The animal will break behind the top of shoulder to loin muscle. There will be a dip from rib cage to shoulder blade. These breaks or dips are a structural defect and should not be tolerated.

SHOULDER WIDTH

Shoulder width should be same as rump length. Shoulder width minus rump length. Ideal range is 0 or +.5 or -.5 inches.  Too wide of shoulders in a female will cause a lack in milk production.  Too narrow a shoulder in the female requires more maintenance and results in reproductive problems and is high maintenance. In the cow, the shoulders should balance the rump length

RUMP LENGTH PERCENT

The rump length percent is the percentage the rump makes up of the body length or the 2/3 body length. Divide the 2/3 body length into the rump length for the rump length percent.  In females the rump length should not exceed 40% of the 2/3 top line.   38% to 40% is the ideal range. Either side of this is in the extreme.  The rump length sets the standard for femininity.

FLANK CIRCUMFERENCE

This is a fertility and maternal trait indicator.
The greater the flank circumference is than the heart girth the higher the fertility.

  • High flanked cows have a tendency to be a little more flighty.
  • High flanked cows have less meat on the rump.
  • High flanked cows have a tendency to be higher maintenance.
  • High flanked animals will take longer to finish on grass.
  • The flank area should be 2 too 10 inches larger than girth at 12 months.
  • Larger is better.
  • A small difference of less suggests that other fertility indicators should be checked.
  • Fill can affect as much as 3 inches.

RUMP WIDTH PERCENT

Rump width divided by the rump height.   This percentage indicates ability of self-fleshing, ease of keeping, reproductive efficiency, and indicator of volume of meat on rump. The minimum rump width % is 40% of rump height. The wider and deeper the rump and flank the higher the maternal characteristics. The wide deep rump represents femininity and reproductive efficiency. Wide rumped cows have sons and daughters with wide rumps.

ADJUSTED RUMP WIDTH

Rump width minus rump length. The rump width should be 2.5 inches wider than its length. The wider the rump is than long is a high fertility indicator.

  • The wide rumped cow has sons with short necks.
  • The wide rumped cow has daughters with wide rumps.
  • The wide rumped cow has more meat in the rump area and produce sons and daughters with more meat.
  • The progeny will mature earlier and finish by 16 to 18 months of age on grass

RUMP HEIGHT

Rump height correlates highly with gain-ability.
Tall animals tend to be out of balance, slow to come into puberty, thus lower in fertility and reproductive efficiency. They have smaller loins. For overall performance and finishing on grass a frame score of 3.5 to 4.5 works best.

THURL

The thurl should be 13% of the rump height or greater. Greater is better if the slopes of the rump are at the proper angle.  Thurl should be 13% of hip height or greater.   This indicates pelvic depth and structural soundness of hind legs.   If the thurl is properly in place the animal will track correctly (back foot in front track).  The measurement is taken from ground to stifle joint to top of back.  Proper structured thurl makes for ease of calving.

UDDER
The udder should be small and tucked neatly between the back legs with
four equally placed nipples 3-4 inches long. The udder should attach high
up behind the back legs for longevity and soundness.
The udder should blend into the lower part of the belly very smoothly
with no V or crevice between the udder and stomach. The udder should not be tilted up in front. Tilted udders are a structural defect resulting from the sire and his scrotal makeup. Tilted udders have less milk. The udder has a direct influence on the scrotal make up and navel area of her sons.

This information can be overwhelming!  We now have all of our measurements and know what the different measurements and percentages mean, but how do we compile it in an understandable fashion and relate it to the individual animal?  That will be my next post.

While you are studying how to measure your replacement heifers, take a minute and visit with our Missouri partner, Bruce Shanks of Sassafras Valley Ranch.

Follow Holiday Ranch on Facebook http://www.facebook.com/pages/Holiday-Ranch/306824716001982?sk=wall

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One Response to “Linear Measurements to Evaluate Heifers”

  1. […] Linear measurements or physically measuring certain areas of the live animal to determine their frame score and comparing their phenotype to that of an “ideal” set of measurements. We use blood samples to check for pregnancy […]


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