1. SELECTING
BEEF CATTLE
Agriscience 332
Animal Science
#8399
TEKS: (c)(7)(B)

2. Introduction
Knowledge of selection practices
and how to properly apply them
can help improve a producer’s
herd genetics and economics.
Photo by Bill Tarpenning courtesy of USDA Photography Center.

3. Methods of Selection
The methods of beef cattle selection
that are used must support the goals
of the production system type.
The objectives of commercial
cow/calf producers and purebred
breeders are similar; however, the
management practices may be quite
different.

4. The goal of most cow/calf producers
is to produce the maximum pounds
of calf at the most economical cost.
Photo by Gary Kramer courtesy of USDA Natural Resources Conservation Service.

5. The goal of the purebred breeder is
to produce breeding cattle for
purchase by other breeders and
commercial cow/calf producers.
Photo by Bill Tarpenning courtesy of USDA Photography Center.

6. The three principle considerations for
selection of breeding animals are:
• Visual appraisal,
• Pedigree, and
• Performance.

7. Depending upon the producer’s
objectives, varying degrees of
emphasis are placed on the
selection factors.
For example, the purebred breeder
often places more emphasis on
pedigree than does the cow/calf
producer.

8. Visual Appraisal as a
Basis of Selection
Selection by visual appraisal has
been responsible for much of the
genetic improvement of beef
cattle.

9. Visual appraisal can be a good
indicator of an individual’s offspring
characteristics, such as:
• Frame size,
• Muscle and body structure,
• Predisposition to waste,
• Feet and leg structure, and
• Breed character.

10. A close relationship exists between
the appearance of a breeding beef
animal and its reproductive
efficiency, a critical factor in the
success of purebred and
commercial operations.
Breeding cattle must be able to
reproduce regularly over a long
period of time to be economically
productive.

11. An understanding of beef animal
parts and their description is
necessary for effective
communication in any segment of
the beef industry involving live
cattle or carcass evaluation.

13. The following characteristics
should be visually appraised:
• Body structure,
• Soundness of feet and legs,
• Muscling and muscle structure,
• Frame or skeletal size,
• Reproductive soundness,

14. • Predisposition to waste,
• Breed character,
• Temperament, and
• Conformation score.
These characteristics are then
combined with production records and
pedigree analysis for effectiveness in
selecting beef breeding animals.

15. Body Structure
Body structure is a major factor
in the visual evaluation of beef
cattle.
The general body structure of an
animal is a good indicator of
production characteristics.

16. Cattle with the correct body
structure will be more efficient
producers, thus having more
potential for economic returns.
To evaluate body structure, look
for the following factors in the
animal.

17. • The neck of a beef animal should
be moderately long, which is an
indicator of growth;
• The animal should be clean in the
throat area;
• The loin and rump should be long,
wide, and level causing the
animal to be long and strong in its
back;

18. • Extremely short-bodied and short-
legged cattle are associated
with excessive fat deposition
and inefficient growth rates;
• Long-legged and long-bodied
cattle are associated with late
maturity and low-quality grades;

19. • The round of beef cattle should be
deep and wide when viewed
from the rear, with the widest
portion being about midway
between the tail head and hock;

20. • The shoulder should be well-
muscled, but free of
coarseness;
• Offspring with extremely heavy,
open shoulders can cause
calving difficulties;

21. • A beef animal should be
moderately trim in its rear flank,
underline, and brisket, and carry
minimal excessive waste;
• At the same time, the animal
should show good depth of body,
indicating body capacity and
overall productiveness.

22. • An animal that has a wide, full
heart girth, adequate spring of the
fore-ribs, and a wide chest floor
and chest indicates proper growth
and function of vital organs; and
• Adequate width between front and
hind legs also indicates good
body capacity and muscling.

23. Soundness of Feet and
Legs
Visual appraisal of structural
soundness is useful in evaluating
longevity and productivity.
For cattle to travel and remain
sound during long productive
lives, they must have correct
conformation of feet and legs.

24. Factors to look for when evaluating
soundness:
• The legs should be squarely set
under the four corners of a
beef animal and be reasonably
straight;
• The shoulders should not be too
straight, as this may be an
indicator of leg problems; and

25. • Animals that exhibit signs of
structural abnormalities should not
be selected as potential breeding
animals.

26. Examples of common structural
abnormalities of the feet and legs
include:
Post-legged – hind legs are set too
far back, thus making
them too straight;
Sickle-hocked – hind legs are set too
far under the body.

28. Knock-kneed – front legs are close
at the knees and
feet are “toed-out”.
Pigeon-toed – front feet are “toed-in”.

29. Bow-legged – hind legs are wide at
the hocks and feet
are toed-in”.
Cow-hocked – hind legs are close at
the hocks and feet
are “toed-out”.

31. An animal’s productive longevity is
largely dependent on its structural
soundness.
Longevity is important in all phases
of beef production because it
affects the number of replacement
animals needed to maintain a herd.

32. An animal’s movement should be
free and easy as opposed to being
uncoordinated, slow, stiff, and
restricted.
Animals with uneven, small, curled,
or twisted toes and crooked feet
usually become lame and should
not be selected.

33. Unsound feet, legs, and joints
affect the ability of bulls to follow
and breed cows, which reduces
herd productivity.
Breeding animals with feet or leg
problems are not physically
capable of being productive over
an extended period of time.

34. Muscling and Muscle Structure
Evaluating muscling is another
important factor to consider when
visually appraising beef cattle.
Muscling is the source of meat for
consumers and, therefore, is
essential to evaluate.

35. Muscling is indicated by:
• Conformation,
• Overall thickness and fullness,
and
• Muscular development in relation
to skeletal size.

36. Bulls
Thick, heavy, long muscling is
desired by bulls and is indicated by:
• Length and size of muscling in the
forearm and gaskin areas;
• Width and bulge of muscling in the
stifle area as viewed from the rear
and side;

37. • Width between the hind legs
(both standing and walking);
• Thickness, length, and bulge of
muscling in the back and loin;
and
• Expression of muscling in the
shoulder and round as the animal
moves.

38. Length of muscling is largely
determined by length of bone.
If muscling is thick and bulging in
one area of an animal’s body, the
animal is usually heavily muscled
throughout the body.

39. Animals with extreme
muscling, to the point
of being impaired in
movement or
appearing “double-
muscled,” should not
be selected.
“This Piedmontese-Hereford
crossbred calf displays classic double
muscling because it inherited a
defective myostatin gene from both
of its parents.” (USDA-ARS)
Photo by Keith Weller courtesy of USDA Agricultural Research Service.

40. Cows and Heifers
Muscling in females should be
long, smooth, and of moderate
thickness.
In females, short, coarse, bully
muscling is usually a sign of poor
reproductive efficiency and low
milking ability.

41. A female’s overall body shape
should have a slightly angular
appearance, with a slight skin fold
shown by the dewlap down the
throat and in the brisket area.

42. The shoulders should be
moderately muscled and “clean.”
The shoulder blades should
extend to the top of the vertebrae,
giving a lean appearance to the
top of the shoulders.

43. Frame or Skeletal Size
Frame size is a numerical
description that refers to an
animal’s skeletal size; that is, its
height and body length in relation
to its age.

44. Cattle reach mature size and weight
and different rates.
Age Percent of
Mature Height
Percent of
Mature Weight
7 months 80% 35% - 40%
12 months 90% 50% - 60%
Comparison of Rates of Maturity
for Height and Weight

45. Frame size indicates growth, but
also is an indirect measure of the
composition, or fat-to-lean ratio, of
beef animals.
Frame size can be used to
approximate projected mature size
and to characterize performance
potential and nutritional
requirements of an animal.

46. A producer should select a frame
size that best fits their feed
resources, breeding systems, and
markets.

47. Larger-framed cattle, such as most
exotic breeds of cattle, tend to grow
faster, mature later, be leaner, and
produce more pounds of edible beef
per day of age than smaller-framed
cattle.
Image from IMS.
Image from IMS.

48. Small-framed animals, such as most
British breeds of cattle, tend to be
shorter in stature, earlier maturing
for their age, and tend to finish and
mature at lighter body weights.
Image from IMS.

49. The Beef Improvement Federation
(BIF) has correlated hip height with
frame types.
When taking this measurement,
care must be take to ensure that
animals are standing on level
ground and that all animals are
measured at the same point.

50. Hip height measurement should be
taken at the hip directly above the
hook bone.

51. Most commercial producers use
medium-framed cows, as they
are more economical.
Usually, the cows are bred to
large-framed bulls.

52. Typically, small-framed cows
produce calves with less growth
potential and have little salvage
value.

53. Large-framed cows are not as
economical because they have
higher body maintenance
requirements.
However, some large-framed cows
are required in purebred herds to
produce large-framed bulls.

54. Animal scientists at Texas A&M
University recommend that bulls be
a minimum of frame size 6 (51
inches at the hip) at 12 months of
age and weigh 22 or more pounds
for each inch of height (minimum of
1,120 pounds).

55. Mature bulls should weigh a
minimum of 1,700 pounds and have
a minimum hip height of 57 inches.
These researchers also recommend
that bulls weigh at least 600 pounds
at weaning and exhibit rapid, efficient
growth rates, thus maximizing
muscle production and minimizing fat
deposition.

57. Age
(months)
Frame Score
1 2 3 4 5 6 7 8 9 10 11
24
30
36
48
46.4 48.3 50.3 52.3 53.9 56.0 58.0 60.0 62.0 64.0 66.0
47.3 49.3 51.3 53.2 54.9 57.0 59.0 61.0 63.0 65.0 67.0
48.0 50.0 51.9 53.8 55.5 57.5 59.5 61.5 63.5 65.5 67.4.
48.5 50.4 52.3 54.1 55.9 58.0 60.0 62.0 63.9 65.8 67.7
Hip Heights (inches) and Frame
Scores for Mature Bulls
Source: Beef Improvement Federation Guidelines

59. Age
(months)
Frame Score
1 2 3 4 5 6 7 8 9 10 11
24
30
36
48
43.1 45.0 46.9 48.8 50.7 52.5 54.5 56.4 58.2 60.1 62.0
43.8 45.8 47.5 49.4 51.3 53.1 55.1 57.0 58.9 60.8 62.5
44.2 46.1 48.0 49.8 51.8 53.6 55.5 57.2 59.2 61.0 62.8.
44.6 46.5 48.2 50.0 52.0 53.9 55.8 57.5 59.4 61.2 63.0
Hip Heights (inches) and Frame
Scores for Mature Cows
Source: Beef Improvement Federation Guidelines.

60. The USDA standards for feeder cattle
grading uses three separate frame
sizes: small, medium, and large.
Frame Size1
Steers weight Heifers weight
Small <1100 lbs. <1000 lbs.
Medium 1100 – 1250 lbs. 1000 – 1150 lbs.
Large >1250 lbs. >1150 lbs.
Relationship Between Sex, Weight, and Frame
Size Grades Used for Feeder Cattle Grading.

61. Small-framed
Medium-framed
Large-framed
Image from IMS.
Image from IMS.
Image from IMS.

62. Reproductive Soundness
Male and female breeding
stock need to be evaluated
for reproductive soundness.
Image from IMS.

63. Bulls
The following factors affect
reproductive soundness in bulls:
• Bulls should be free of eye
problems (e.g., cancer, pinkeye,
and cloudy eyes) because good
vision is required to find cows
that are in heat;

64. • Soundness of feet and legs is
critical because bulls will have to
travel in order to mount and mate
with females;
Image from IMS.

65. • Testicles should be well-
developed, uniform in size, and
properly balanced in relation to the
age and size of the bull;
Image from IMS.

66. • The scrotum and testicles should
be a minimum of 30 centimeters
(approximately 12 inches) in
circumference on a twelve-month
old bull to indicate adequate
reproductive ability;

67. • The sheath region should be “tight”
or free from excess skin folds
and obstructions; though bulls
with Brahman breeding will exhibit
a more pendulous sheath; and
Image from IMS.

68. • Bulls should exhibit adequate
libido, or sex drive.
Image from IMS.

69. Cows and Heifers
The following factors affect
reproductive soundness in female
cattle:
• A productive cow will have a
large spring of ribs, indicating
adequate body capacity to carry a
large, healthy calf;

70. • Females should be wide and long
from hip to pin bones and deep
from pins to stifle joint,
indicating calving ease;
Image from IMS.

71. • The widest portion of the fertile
cow should be the midrib; and
Image from IMS.

72. • The udder should be strongly
attached with a level floor and the
teats should be proportional to
body size.
Image from IMS.

73. Predisposition to Waste
The location and degree of fat
deposition is very important in the
beef industry.
Finish affects carcass yield.

74. Consumers prefer an optimum
combination of intramuscular fat
(marbling) and total fat (finish).
Finish and marbling
contribute to the
juiciness, flavor, and
palatability of meat.
Photos by M.A.R.C. courtesy of USDA Agricultural Research Service.

75. A correct degree of finish is
necessary to ensure proper quality
and high cutability in the carcass.
Photos by M.A.R.C. courtesy of USDA Agricultural Research Service.
Carcass with high marbling and
low lean-to-fat ratio.
Carcass with low marbling and
high lean-to-fat ratio.

76. The degree of finish on a breeding
animal will vary depending on the
energy level and amount of feed
the animal is being fed.
The season of the year is also a
factor in fat deposition.

77. Bulls
Bulls should naturally show an
even, thin distribution of fat, even
when they are being fed heavily or
during the non-breeding season.
Excessively fat bulls will lack libido.

78. Indicators of predisposition to
excessive waste are:
• Large amounts of loose hide in
the dewlap or brisket,
• Excessive depth in the flank,
and
• Loose hide in the twist.

79. Cows and Heifers
Females should never be fed to
excessively fat conditions.
Fatty tissue is deposited in their
udders and around their
reproductive organs, resulting in
reduced milk production and lower
reproductive rates.

80. Females will normally deposit more
fat in the brisket, along the
underline, and over the ribs and
back than will bulls, especially
during their dry season.

81. The fat deposits can be
advantageous if not excessive,
because these cattle will require
less feed during the winter, in
comparison to “poor-doing” or
“hard-fleshing” cattle.

82. Breed Character
Each particular breed of animal is
composed of a unique combination
of genetics that allows the animal to
be recognized as a member of that
breed (i.e., its phenotype).

83. Breed character is the “trademark”
or specific identity for the breed that
the animal represents.
Image from IMS.

84. In purebreds, the traits that
distinguish one breed from another
include:
• Hair color or hair color patterns,
• Head size and shape,
• Ear size, shape, and carriage,
• Dewlap characteristics,

85. • Sheath characteristics,
• Overall body shape, and
• Horned or polled.

86. If an animal is being purchased as
a purebred, it should exhibit the
significant characteristics of that
breed, thus making it eligible for
registration.
Image from IMS.

87. Breeders should purchase the
breed or breeds of cattle that will
produce the type of offspring most
desirable for their production system
and end market.

88. Temperament
The temperament, or disposition,
of the breeding animal one selects
can be important to their overall
productivity.

89. Genetic makeup and environmental
conditions are two factors that
affect the disposition of cattle.
A producer’s handling methods also
have a significant impact on an
animal’s temperament, but some
breeds have a tendency to be more
nervous than others.

90. Frequently, indicators of bad
temperament are high-headedness,
nervousness, frequent urination,
charging, and kicking.

91. Temperament in cows is critical
because gentle, easy-handling
mothers usually raise better calves.
A bad-tempered bull can be
dangerous regardless of his genetic
superiority.

92. Cattle with very poor dispositions
should be culled to prevent human
injury, decrease excitability of other
animals, and minimize repair costs
of facilities from damages caused
by destructive behaviors.

93. However, culling is not an effective
solution if bad handling is causing
the problem.
In this case, the handling methods
and facilities should be examined.

94. Sales are often not a good time to
make decisions about an animal’s
temperament.
Frequently, sale animals will express
abnormal behaviors because of pre-
sale handling and processing.
These behaviors may not be a true
indicator of the animal’s temperament
under normal pasture conditions.

95. When possible, selection of animals
in the pasture is a more desirable
option for determining temperament.
Image from IMS.

96. Conformation Scores
A conformation score is often
provided with sale cattle by a breed
association, an individual breeder,
or some other authority.
Conformation scores are usually
based on form, shape, and visual
appearance.

97. Example of conformation scoring system:

98. This evaluation form could be used
in the selection of females, as well
as, bulls for a breeding cattle herd.

99. Pedigree as a
Basis of Selection
Pedigree data is information on
the genotype or performance of
ancestors and collateral relatives
of an individual.
With pedigree selection, animals
are selected based on the merit
of their ancestors.

100. If a pedigree is used, greatest
value should be placed on the
most recent ancestors because
of their close genetic relationship
to the animal being evaluated.

101. The genetics in a superior animal
is halved in each successive
generation; therefore, parents and
grandparents are the only animals
that will contribute significantly to
an offspring’s genotype.

102. The best uses of
pedigree information
are in the selection
of young animals,
before production
and performance
records are available, and in the
selection of highly heritable
characteristics such as longevity,
yearling weight, and mothering
ability.
Image from IMS.

103. Pedigree information is also useful
in identifying genetic abnormalities,
as well as, selecting for traits
expressed only in one sex.
However, more emphasis should
be placed on individual
performance and progeny testing
than on pedigree.

104. Performance as a
Basis of Selection
Performance testing is the
measuring of traits that can be
observed and may include either
individual performance or progeny
testing.

105. Performance testing usually
focuses on the traits that have the
greatest economic importance.
Image from IMS.

106. Potentially, the most improvement
is offered by those traits that are
highly heritable, as indicated in the
table on the following page.
The heritability percentage
identifies that portion of variation
that is passed on from parent to
offspring.

108. There are considerable differences
in cattle regarding the transmission
of economically important traits,
such as birth weight, mothering or
milking ability, weaning weight,
yearling weight, efficiency of gain,
carcass merit, and conformation
score.

109. Genetic improvements can be
made by evaluating individual
performance criteria and using
the results of progeny testing.
One must understand that these
traits are affected by the
environment, as well as, by
genetics.

110. Measurements of Reproductive
Performance
Reproductive performance has the
highest economic value of all the
traits.
Image from IMS.

111. One of the most important measures
of reproductive performance is the
weaned calf crop percentage.
For each 10% drop in calf crop
weaned, an increase of about 20%
occurs in production costs (as
determined under Texas conditions).

112. Reproductive performance can be
improved through selection, based
on carefully kept records of
reproduction.
Reproductive records that are
helpful include conception rate, calf
crop percentages (born and
weaned), calving interval, and birth
weight relative to calving ease.

113. Conception Rate
The conception rate of a herd is
determine by comparing the number
of breeding age females that
conceive or become pregnant to the
total number of breeding age
females that were exposed to a bull
during breeding season.

114. A conception rate percentage can
be calculated by using the
following formula.
The number of cows that conceived at the end of
a breeding season is divided by the number of
cows exposed to a bull during the breeding
season and then multiplied by 100% to get the
conception rate percentage.
# Cows Conceived
# Cows Exposed
X 100% = Conception Rate

115. If a cattle producer has 100 cows
that are exposed to bulls during the
breeding season and finds that 95 of
the cows are pregnant at the end of
the breeding season, the conception
rate would be calculated as follows.
95 Cows Conceived
100 Cows
Exposed
X 100% = 95% Conception Rate

116. Calf Crop Percentage (Born)
Calf crop percentage born is
determined by dividing the number
of calves born by the number of
cows exposed to a bull during the
breeding season.
# Calves Born
# Cows
Exposed
X 100% = Calf Crop % (Born)

117. If the cattle producer had 93 calves
born out of the 100 cows exposed
to bulls during the breeding
season, his calf crop % born would
be as follows.
93 Calves Born
100 Cows
Exposed
X 100% = 93% Calf Crop Born

118. Calf Crop Percentage (Weaned)
Percentage weaned is computed by
dividing the number of calves
weaned by the number of cows that
were exposed to bulls during the
breeding season.
# Calves Weaned
# Cows
Exposed
X 100% = Calf Crop % (Weaned)

119. If the cattle producer was able to
wean 90 calves from the 100 cows
exposed to bulls during the breeding
season, the percentage of calf crop
weaned would be as follows.
90 Calves Weaned
100 Cows
Exposed
X 100% = 90 % Calf Crop Weaned

120. Calving Interval
Calving interval is a measurement
of the average length of time in days
between successive parturitions or
calvings for all of the breeding age
females in a herd.

121. Calving interval would be calculated
for each cow and then an average
would be computed for the herd,
which would be a measure of the
fertility of the herd.

122. Cow A
Calving Dates: 3/1/05 and 3/1/06 = 365 days
Cow B
Calving Dates: 4/1/05 and 8/1/06 = 485 days
Cow B should be culled for poor reproductive
efficiency.

123. Birth Weight Related to Calving
Difficulty
Average birth weights of offspring
should be considered when
selecting breeding beef cattle
because they are directly related to
ease of calving.

124. Calving difficulty, or dystocia, can
increase calf losses, cow mortality,
and veterinary and labor costs, as
well as, delay return to estrus and
decrease conception rates.

125. Calves that are heavy at birth
require a larger birth canal or
pelvic area for normal delivery
than do lighter calves.
Birth weights in
excess of 90 pounds
usually create
calving difficulty.
Photo by Scott Bauer courtesy of USDA Agricultural Research
Service.

126. Heifers are more likely to
experience calving difficulty; so
more care must be taken when
selecting bulls for heifers than for
cows.

127. Many producers of breeding stock,
especially bulls, will provide buyers
with calving ease information, such
as calving difficulty scores.

128. The primary goal of every cow/calf
producer should be to produce one
live healthy calf from each cow
every twelve months.
Cows that are incapable of meeting
these standards should be culled.

129. Palpation can assist producers in
early detection and elimination of
poor producers.
Heifer replacements should be
selected only from cow with
excellent reproductive records.

130. Fertility Testing of Bulls
Fertility testing is an important
consideration when selecting a bull.
Both young bulls and old bulls,
should be fertility tested before
being used.
Fertility testing involves physical
and visual evaluation of the bull’s
reproductive soundness.

131. A breeding soundness exam
(BSE), a common method for
fertility testing bulls, includes:
• A physical examination of the
bull’s reproductive system,
• A measurement of the bull’s
scrotal circumference, and
• An evaluation of the bull’s
semen.

132. The bull’s external genitalia can be
examined visually and should not
exhibit any structural abnormalities.
Internal organs of the bull’s
reproductive system can be
examined for size, shape, and
consistency through rectal
palpation.

133. Scrotal circumference should be
evaluated because of its
relationship to sperm production
and semen volume.
The bull’s semen should be
evaluated for volume, morphology,
and motility.

134. If conception rates are a problem,
fertility testing of bulls should not be
overlooked.
An entire breeding season could be
lost by using an infertile sire.

135. Previously tested, fertile bulls may
later experience infertility because
of disease, injury, or other
reasons.
It is a good practice to fertility test
before each breeding season.

136. Measurements of Growth and Gain
Performance
The following measurements are used to
evaluate growth and gain performance:
• 205 Days Adjusted Weaning Weight,
• Yearling (365-day) and Long Yearling
(452 or 550 days),
• Post-weaning Rate of Gain, and
• Weight Per Day of Age.

137. Weaning Weights (Adjusted to 205
Days)
Weaning weights are used to
evaluate differences in mothering
ability of cows and the growth
potential of calves.
For best estimates of genetic worth
of weaning weight, it is necessary to
adjust individual calf records to a
standard basis.

138. Most organizations that record
weaning weights use weights
taken between 160 to 205 days
and adjust these weights to a
uniform age of 205 days.

139. This procedure is summarized by
the following formula.
205-Day Weight (lbs.) =
Actual Weight – Birth Weight
Age in Days
X 205 Days + Birth Weight
If the actual birth weight is unknown,
70 can be used for this figure.

140. The 205-day weight should then be
adjusted for the age of the dam and
for the sex of the calf.
This is necessary for uniformity in
evaluating 205-day weights.

141. The following table can be used to
adjust the 205-day weights to a mature
dam equivalent for bulls and heifers.

142. Weaning weight ratios within sex
groups are calculated by dividing
each individual animal’s 205-day
weaning weight, adjusted for age
of dam, by the average of its sex
group.
Weaning weight ratios provide a
record of each animal’s deviation
from the average of its
contemporaries.

143. Weaning weight ratio is calculated
by using the following formula.
Weaning Weight Ratio =
Individual 205-Day Weight__________
Average 205-Day Weight of Animals in the
Group
X 100%

144. Yearling (365-day) and Long
Yearling Weights (452 or 550 days)
Yearling weights at 365 days are
particularly important because of
their high heritability and high
genetic association with efficiency
of gain.

145. Yearling weight is the best performance
measure for selecting bulls.
It is closely related to the eventual
market weight of the steers to be
produced.
Usually, the weights are adjusted to a
365-day basis, yearling weight, or to a
550-day basis, long yearling weight.

146. The following formula is used to
calculate yearling weight.
Adjusted 365-Day Weight =
Actual Final Wt. – Actual Weaning Wt.
Number of Days Between Weights
X 160 Days + Adjusted Weaning Wt.
(205-days)

147. Adjusted 452-Day Weight =
Actual Final Wt. – Actual Weaning Wt.
Number of Days Between Weights
X 247 Days + Adjusted Weaning Wt.
(205-days)
Adjusted 550-Day Weight =
X 345 Days + Adjusted Weaning Wt.
(205-days)
Actual Final Wt. – Actual Weaning Wt.
Number of Days Between Weights

148. A yearling weight ratio can be
calculated by comparing the
individual’s yearling weight to the
average of a specific sex group.
All animals in a sex group must
have been given similar
environmental treatment for the
weights and ratios to be
meaningful and comparable.

149. The following formula is used for this
calculation.
Yearling Weight Ratio =
___Adjusted 365-Day Weight of Bull_____
Adjusted 365-Day Weight of All Bulls Tested
X 100%

150. Post Weaning Rate of Gain
(Minimum 140 Days on Test)
Individual rate of gain testing is
usually conducted on bull calves or
short yearlings to determine their
ability to grow.

151. Testing the rate and efficiency of
gain is very important in bull
selection as the timing and length of
this test period coincides with the
finishing period of the feedlot phase
for the calves that the bulls will sire.

152. Most of the tests are conducted for
a period of 140 days.
An initial weight is taken at the
beginning of the test and a final
weight at its conclusion.

153. The formula for determining rate of
gain is shown below.
Rate of Gain =
Final “Off Test” Weight – Initial “On Test” Weight
Total Days on Test

154. When making comparisons of
animals on gain tests, particularly
from central gain test stations,
weaning weights and weight per
day of age should be considered
along with the gain test results.

155. According to researchers at Texas
A&M University, bulls on gain tests
should have an average daily gain
of 3.5 pounds, requiring less than
seven pounds of feed for each
pound of gain.

156. An animal’s performance on a test
is influenced by the handling and
management received prior to the
test.
Therefore, it is necessary to include
pre-test adjustment periods.

157. A low weight per day of age and a
high gain per day of age while on
test indicate an extremely low
weaning weight or a long period of
little or no gain before the cattle
were placed on test.
This could mean that much of the
superiority in rate of gain while on
test is compensatory gain instead of
genetic ability to grow rapidly.

158. The compensatory gain may be a
result of low weaning weights
because of poor mothering ability
or other environmental factors.

159. The rate of gain ratio is a
comparison of one animal with the
other animals on the 140-day test.
A ratio of 100 is the group average.
An average daily gain ratio of 110
indicates that a bull is 10% above
the group average for rate of gain.

160. The formula to calculate rate of gain
ratio is as follows.
Rate of Gain Ratio =
_______Individual Rate of Gain________
Average Rate of Gain of Animals in
Group
X 100%

161. Weight Per Day of Age
The weight per day of age of an
individual can be a good indictor of
genetic growth potential.
However, this measure contains a
potentially unreliable variable
because it only uses the actual weight
of the individual and divides by the
actual age in days of the animal.

162. There are not any adjustments for
the age or mothering ability of the
individual’s dam or other
environmental factors, such as
nutritional level after weaning.
Any of these variables could
influence, either negatively or
positively, the animal’s genetic
ability for growth.

163. The formula for calculating weight
per day of age is shown below.
Weight Per Day of Age =
Actual Weight
Age in Days

164. Example of Performance
Data for a Bull
Many breeders provide a
considerable amount of information
on sale animals.
This information is beneficial to
prospective buyers in evaluating the
efficiency and productivity of a bull,
which aids in selection.

165. Below is an example of the information
provided in an advertisement for bulls
completing a test and offered through a
sale.

166. Progeny Testing
Progeny testing is a method of
evaluating an animal’s breeding
value by observing its transmitting
ability through a study of the
characteristics of its offspring.
It is the most accurate method of
selection when adequate tests are
conducted.

167. Progeny testing is particularly
useful in selecting for carcass
traits (when good indicators are
not available on live animals), for
sex-limited traits (milk production
and mothering ability), and for
traits with low heritability.

168. Through the use of progeny testing,
breeders can determine differences
in the genetic ability of their cattle.

169. The primary disadvantage of
progeny testing is that it is not
possible to include cows in the
testing program.
An individual cow will not produce
enough calves in a lifetime for an
accurate evaluation, because the
generation interval for cattle is too
long.

170. Although not completely accurate,
cows can be selected on their
production by evaluating their
calves at weaning.
This factor is
based primarily
on the cow’s
mothering ability.
Photo by Bruce Fritz courtesy of USDA Agricultural Research Service.

171. Carcass Merit
Carcass merit is a production trait
of a bull that can only be measured
through progeny testing.
Carcass merit is measured
primarily by carcass weight,
tenderness, quality grade, and
yield grade.

172. Many cattle breed associations
have devised a system for
recognizing superior meat sires.

173. Usually, the evaluation of 8 to 12
carcasses of a bull’s progeny will
indicate his probable transmitting
ability of carcass traits.
However, when evaluating a sire’s
progeny for carcass merit, the progeny
selected for evaluation should be the
result of random matings, be the same
sex, and be reared under similar
environmental conditions.

174. Quality Traits
When evaluating a sire’s progeny
for carcass merit, the carcasses
are graded for quality traits based
on the overall palatability
(tenderness, juiciness, and flavor)
of the edible portion of the carcass.

175. USDA quality grades include prime,
choice, select, standard, commercial,
and utility.
These grades are based on the
degree of marbling and the degree
of maturity.

176. Degree of Marbling – intramuscular
fat or fat within the muscle is referred
to as marbling.
The amount and distribution of
marbling is evaluated in the cut
surface of the ribeye muscle
between the 12th
and 13th
rib.
The degree of marbling is the most
important factor in determining
quality grade.

177. Degree of Maturity – carcass maturity
is based on the physiological age of
the animal as indicated by the bone
and cartilage characteristics, and the
color, texture, and firmness of the
ribeye muscle.
When evaluating carcasses, emphasis
is placed on cartilage and bone
maturity.

178. As an animal ages, cartilage
becomes ossified into bone, lean
meat darkens in color, and the
texture of meat becomes coarser.

179. Quantity Traits
The carcass is also graded for
quantity traits based on the amount
of marketable meat (boneless,
closely-trimmed retail cuts) the
carcass will yield.
USDA yield grades range from
1 to 5, with YG1 being the highest
yielding carcass and YG5 the

180. Yield grades are based on the following
factors:
• Amount of KPH fat (kidney, pelvic,
and heart);
• External fat thickness over the 12th
rib,
• Area of the ribeye muscle at the 12th
rib, and
• Hot carcass weight.

181. Cattle producers should select sires
capable of producing superior beef
carcasses.

182. Beef cattle specialists at Texas
A&M University recommend that
sires selected produce progeny that
will yield carcasses grading at least
low choice with a minimum “small”
degree of marbling and a maximum
of 0.04 inches of outside carcass fat
per 100 pounds of live weight.

183. The carcasses should contain
ribeyes with areas of 1.1 to 1.4
square inches per 100 pounds of
live weight, have a minimum
dressing percentage of 60%, and
consist of 50% or higher boneless
retail trimmed loin, rib, round, and
chuck.

184. Using EBV and EPD in
Selecting Beef Cattle
Estimated Breeding Value (EBV) is
an estimate of an individual’s true
breeding value for a trait.
EBV is based on the heritability of
the trait and the performance of the
individual and close relatives.

185. EBVs for growth traits are generally
expressed as ratios.
EBVs include the individual’s
performance records, as well as
records of collateral relatives, such
as the sire, dam, sire of dam, and
half brothers and sisters.

186. EBVs are valuable in the selection
of young bulls and females for birth
weight, weaning weight, yearling
weight, and mothering ability (milk).

187. Example: A bull with an EBV for
yearling weight has a genetic potential
or estimated breeding value of 8%
above the average of those bulls to
which he was compared.
The value to be placed on this figure
is dependent on whether he was
compared to other bulls from his herd,
to bulls from several different herds,
or to many other bulls of his breed.

188. Expected Progeny Difference (EPD)
provides a prediction of future
progeny performance of one
individual compared to another
individual within a breed for a
specific trait.
The most common EPDs reported
are birth weight, milk, weaning
weight, maternal influence, and
yearling weight.

189. EPDs are based
on a herd or
breed average.
Different breeds have different
bases, which makes it difficult to
compare EPDs across breeds.
Photo by David Riley courtesy of USDA Agricultural Research Service.

190. The Expected Progeny Difference
(EPD) is equal to one-half of the
Estimated Breeding Value (EBV).
Using the same bull from the previous
example, the amount of change that
could be expected in yearling weights
of his offspring would only be a 4%
increase because the bull transmits
half of the trait while the dam transmits
the other half.

191. The accuracy (ACC) of the EPD is
given for each trait and reflects the
degree of relevance of the
information used to calculate an
individual EPD.
The accuracy is a measure of
confidence that the EPD reflects the
true genetic merit of an animal.

192. Accuracy can be classified into
three basic categories:
• Low (.00 – 0.50),
• Moderate (0.51 – 0.70), and
• High (0.71 – 1.00).

193. The use of EPDs allows producers
to make comparative selection
decisions for beef cattle traits of
economic importance.
The most economical way that a
commercial breeder can obtain the
use of proven superior sires is with
artificial insemination (AI).

194. Summary
The systematic use of sire
summaries, in conjunction with
other performance and pedigree
data, as well as visual appraisal,
can be beneficial tools for beef
cattle producers.

195. Knowledge of selection methods
can help producers reduce the risks
associated with beef cattle
selection and improve the genetics
and productivity of their herds.

196. ALL RIGHTS RESERVED
Reproduction or redistribution of all, or
part, of this presentation without
written permission is prohibited.
Instructional Materials Service
Texas A&M University
2588 TAMUS
College Station, Texas 77843-2588
http://www-ims.tamu.edu
2007