Sheep Evaluation Flashcards
Lighter muscled
Maternal breeds
Income primarily on wool
Looser hided
White Face
Bred for muscle
Tighter hided
Black Face
Bred for meat
Lighter weight
Smaller
Heavy muscle for weight
Hair Sheep
Live sheep are sold primarily on a
weight basis
Factors impacting dressing percentage in sheep:
Fill
Weight of pelt
Degree of muscling
Fat
What is used to calculate YG in sheep
Back Fat
More accurate estimation of fat on the carcass
Body Wall
Used to determine the percentage of boneless, trimmed, retail cuts
Body Wall
Driven by fat and maturity
body wall
Immature rib of BW is
0.6 in
Mature rib of BW is
0.8 in
More accurate estimation of fat on the carcass
Body Wall
Used to determine the percentage of boneless, trimmed, retail cuts
Body Wall
Body wall is what plus what
rib + fat
How to get REA of black face sheep
0.024 x Live Weight
How to REA of White Face sheep
0.021 x Live Weight
Accounts for 1.5 - 6.0% of carcass weight in sheep
KPH
Not a factor in lamb carcass evaluation
KPH
is removed in commercial practice
Kidney and Pelvic
Based on the amount of external fat present (back fat) in sheep
Yield Grade
What is BCTRC
Boneless, Closely Trimmed Retail Cuts
Do you want to have a high BCTRC or Low BCTRC
High because BCTRC represents percentage yield of usable prodcuts
What are the 4 factors that goes through BCTRC
Carcass weight
Fat thickness
Body wall thickness
Ribeye area
What is the BCTRC for Fat/light muscled sheep
43%
What is the BCTRC for Trim/heavy muscled sheep:
50% +
Fill in the blanks of the BCTRC equation: 50 – (0.085______) – (4.4_____) – (3.5_____) + (2.4_____)
HCW, BF, BW, REA
BCTRC is needed to calculate live market lamb value.
False
If lamb A has a BCTRC of 48% and lamb B has a BCTRC of 44%, which lamb is lower cutability?
Lamb B because it has a lower BCTRC
3 Factors affecting quality grade in sheep
Flank streaking
Conformation
Maturity
Approximately of 90% of lambs harvested will grade
Choice or Prime
Why is streaking used
Lambs are typically not ribbed
Higher amount of fat deposit when looking at flank streaking means
Higher marbling
Shape of the carcass, both fat and muscle
Conformation
What are the two regions you look at for conformation
Leg and Loin
Break joints
Young Lamb
Ribs are red and rounded
Young Lamb
Lean is pinkish-red in color
Young Lamb
One break and one spool joint
Yearling Mutton
Rib bones are moderately wide, flat, and white
Yearling Mutton
Flank muscles are slightly dark red
Yearling Mutton
Two spool joints
Mutton
Rib bones are wide, flat, and white
Mutton
Flank muscles are dark red
Mutton
Is the primary driver in determining sheep yield grades
Backfat
