Transcript Introduction to Live Animal Evaluation

Introduction to Breeding
Livestock Judging and
Evaluation
Introduction to Beef Selection
Criteria for Beef Selection
 Soundness
 Structural
 Reproductive
 Volume
and Capacity
 Muscle
 Skeletal
Extension
 Femininity/ Masculinity
Ideal Beef Heifer
Structural Correctness
 Correct
joint angles
 Shoulder,
knee, hock and pastern
 Strong
top
 Level rump structure
 Hooks
 Large,
to pins
square foot
 Adequate bone
Structurally Correct Heifer
Structurally Correct Heifer
Level rump
Strong top
Shoulder
Angle
Hock
Angle
Knee &
Pastern
Set
Structurally Correct Heifer
Correct Structure: Rear view
Straight Structured
Incorrect Hip and Hind Leg
Structure
Low
Pin
Set
Too
Much
Set
to
Hock
Volume and Capacity
 Most
critical in beef production
 “Fleshing Ability”
 The
ability for a mature female to maintain
body condition while in lactation
 Deep,
bold-sprung ribs for feeding and
breeding capacity
 Wide-chested and wide-based
High Volume Heifer
Deep Fore &
Rear Flank
Lacking Volume!
Muscle
 Heavy
muscled cattle are preferred if
muscle pattern is long and smooth
 Tight, round muscle can inhibit movement
Skeletal Extension
 Long
bodied, long fronted cattle are
preferred
 Cattle being too large in their frame can be
detrimental
 Problems with cattle that are “too big”
 Females
too large as mature cows
 Feedlot cattle do not deposit marbling until
excessive weights are reached
Femininity
 Females
need to be refined through their
shoulder, neck, and head
 Vulvas need to be developed with correct
udder structure
Correct Femininity
Masculinity
 Bulls
need to be masculine about their
shoulder, neck and head, but not coarse
 Bulls should have well developed testicles
that are even in size
 Minimum scrotal circumference
requirements
 Maternal
sire: 34 cm
 Terminal sire: 32 cm
Correct Masculinity
Importance of Testicle Size
 Directly
related to fertility
 Bulls with more developed testicles have
improved semen production
 A larger scrotal size relates to a bull’s
daughters reaching puberty at an earlier age
Introduction to Live Animal
Evaluation
Introduction to Market
Beef Evaluation
Market Beef Evaluation:
Fat Indicators
Tailhead
& Pins
Last
Ribs
Fore
flank
Rear
flank
& Cod
Brisket
Steer A
Steer B
Steer B
Steer A
Market Beef Evaluation:
Muscle Indicators Loin
Quarter/
Rump
Forearm
Stifle
Live Cattle Evaluation
 Weight
 Dressing
Percent
 12th rib fat
 Ribeye area
 Quality Grade
 Yield Grade
Weight
 Live
or Carcass
 Live Weight range
 900
lb to 1500 lb
 Avg: 1200 lb
 Carcass
 550
Weight range
lb to 950 lb
 750 lb
Dressing Percent
 Proportion
of live weight that ends up as
carcass
 Example: 1250 lb steer with a 775 lb
carcass has a dressing percent of 62%
 Range: 55 - 67%
 Avg: 62%
12th Rib Fat Thickness
 Highly
correlated to retail yield
 Predictor of total carcass fatness
 Range: .15 in. to .80 in.
 Avg: .40
 .25 in. considered minimum
Ribeye Area
 Highly
correlated with lean yield
 Predictor of total carcass muscle
 Dependant of carcass weight
 Range: 9.0 - 18.0 sq. in.
 Avg: 12.5 sq. in. for 1150 lb steer
 Rule of thumb: 1.1 sq. in. for 100 lb live wt
Factors Affecting Marbling
 Genetics
 Energy
content of
diet
 Age
of cattle
 Fat
 Time
cover
on feed
 Continental/
Brahman influence
Yield Grade
 Calculated
to predict yield of boneless,
closely trimmed, retail cuts from the round,
loin, rib and chuck
 Based on 4 estimations
 12th
rib fat
 Hot carcass weight (HCW)
 Rib eye area (REA)
 Kidney, pelvic, heart fat (KPH)
Yield Grade
 Range:
1 through 5
1
= Lean and/or Muscular; High cutability
 5 = Fat and/or Light Muscled; Low cutability
 Avg:
2.5