Selection and Judging of Beef

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Selection and Judging of Beef
Animal Science I
Beef
Unit 14
Objectives
• Describe the different types of beef
production systems
• Name the parts of the beef animal (quiz)
• Select superior animals
TYPES OF BEEF
PRODUCTION
Cow-Calf Producers
• Involves keeping a herd of beef cows
• Cows are bred each year to produce calves
that are then sold to cattle feeders
• Difficult to expand (reduce) size quickly
• Prices received are closely related to
supply and demand
– Therefore producers may not always recover
production costs
Cow-Calf Producers: Location
• Western range states and upper Great
Plains on land that is not suitable crop
production
Cow-Calf Producers: Requirements
• Little or no grain
• Less labor
• Lower investment in equipment and
facilities
• Large investment in land
Cow-Calf Producers: Production
Practices
• Cows are typically bred to calve in the Spring
• Calves are weaned in the fall and sold as
feeders
• Sometimes calves are fed through the winter
and sold the next year as yearlings.
• Feeder calves are weaned calves that are
under 1 year of age and are sold to be fed for
growth
• Yearling Feeders are 1-2 years of age and are
sold to be fed to finish for slaughter
Purebred Breeders
• Keep herds of purebred breeding stock
• Provide replacement animals for cow-calf
operations
• Mainly responsible for genetic improvements
• Requires knowledge and skill
• Cost are usually higher
• Takes years to develop a high quality herd
and achieve success
Cattle Feeders
• Feed animals for the slaughter market
• Objective is to produce finished cattle in the shortest
time possible
• Operator buys feeders or yearlings and finished them
in a feedlot
• Requires more grain
• Easy to adjust to changes
• Can expect a return in on investment in 4-6 months
• Facilities are more expensive for confinement feeding
• Higher costs in labor, feed, transportation
• Risky due to fairly large fluctuations in the price of
finished cattle
SELECTION OF BEEF
ANIMALS
Frame Score
• Valuable tool for selecting replacement
heifers and herd bulls
• Measurement based on observation and
height measurement when calves are 205
days of age
• Expected mature size can be made from
frame score
Frame Score Scale
• 1-7 see p. 269 fig 14-1
• English breeds are covered by body types
1-5
• Charolais, Simmental and similarly sized
cattle are usually body types 3-7
Muscle Conformation Scores
•
•
•
•
•
•
•
•
1-7
1. Exceptionally thin calf
2.Very light muscled
3. Light muscled
4. Average muscling
5. Heavy muscled
6. Very heavy muscled
7. Double muscled
Muscle score 1
Muscle Score 7
Conformation Score
• 1-17
• Low scores indicate inferior animals
• 9-11 are animals that are below average for
desirable characteristics
• 12-14 are animals that are average or slightly
below average for some desirable
characteristics
• 15-17 are superior animals that are growthy,
well balanced, well muscled and have
adequate frame
Conformation Score and
Replacement Animals
• Herd sires should have conformation
scores of 14-17
• Replacement heifers should have
conformation scores of 13-17
• Small framed cattle should not be kept for
replacement animals even if their
conformation score is acceptable
Conformation
• The appearance of the live animal
• Includes skeletal structure, muscling, fat
balance, straightness of the animals lines
and structural soundness
• Animals with proper confirmation will
produce the maximum of high value cuts
and will have the minimum of less
valuable bones and internal organs
– See fig. 14-3 p. 271
Desirable Conformation Traits
• Long, trim, deep sided body
• No excess fat on the brisket, foreflank or
hindflank
• No extra hide around the throat, dewlap or
sheath
• Heavily muscled forearms
• Proper height to the point of the shoulders
• Correct muscling throughout the body
• Maximum development of the round, rump,
loin and rib
Ultrasonic's
• The use of high frequency sound waves to
measure fat thickness and loin-eye area
• Useful for selecting meaty animals for
breeding purposes
• Accuracy and value depends on the skill of
the operator
• Widely used
PERFORMANCE RECORDS
Performance Records
• Production Testing
– Measuring a brood cow’s production by the
performance of her offspring
• Progeny Testing
– The evaluation of a bull by the performance of a
number of his offspring
• Performance Testing
– A method of collecting records on beef cattle
herds for selecting the most productive animals
– Used by both purebred and commercial
producers
Performance Testing Are Used To:
Cull low producing cows
Check on percent calf crop
Select replacement heifers and bulls
Measure the productivity of each bull
Improve herd management
Improve the grade of calves produced
Increase the weaning weight of calves
produced
• Give buyers more information
• Provide permananent records
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•
•
•
•
•
•
Steps To Setting Up A Testing
Program
• 1. Identify each cow and calf
• 2. Record birth dates of calves
• 3. Weigh and grade the calves and weaning
time
Adjusting Weaning Weight
• Adjusted to 205 day basis so all calves are
compared equally
• Formula
Actual Weight-Birthweight x 205+BW
Age in Days
• If the calf is not weighed at birth 70 lbs
may be used as an average weight
Pedigree
• Record of the ancestors of an animal
• Only the records of the most recent
ancestors are important in selection
• Ancestors before the 4th generation
contribute very little to the current
generation
• It is important to not keep poor animals
just because they belong to a given blood
line
Other Selection Factors
• Health
– Females should test negative for Bang’s
disease, vibriosis and tuberculosis
– Check for mange, ring-worm and lumpy jaw
– Buying females that have been vaccinated in
calfhood is best
SELECTION OF THE HERD
BULL
Selection of Herd Bull
• Important
• Each calf recieves ½ its genetic make-up
from its sire
• When replacement females are selected
87.5% of their genetic make-up comes
from their last 3 sires in her pedigree.
Sire Summaries
• Provide information on traits that are
economically important
• These include
– Expected birth, weaning and yearling weights
– Carcass information
• REA, Fat Thickness, Marbling, Carcass Weight
– Maternal Breeding Value
• Includes Calving ease
• Recommended for overall heard
improvement
Expected Progeny Difference
• EPD
• Measure of the degree of difference
between progeny of the bull and the
progeny of the average bull of the breed in
the trait being measured
• Calculated from data collected on the
progeny of the bulls
• Given as a +/- value
EPD Example
• An EPD for yearling weight of +65 would
show that the progeny of this bull should
average 65 pounds more at 365 days than
the average bull of the breed.
EPD
Other Traits To Determine A Sound
Herd Bull
• Scrotal circumference
• No apparent physical or genetic defects
– Sickle hocked, pigeon toed, splay footed,
crooked ankles should not be selected
• Disposition
• No record of dwarfism
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