Introduction to Live Animal Evaluation Kenneth Geuns Michigan State University Dept. of Animal Science

Introduction to Market Beef Evaluation

Market Beef Evaluation: Fat Indicators Tailhead & Pins Last Ribs Brisket Fore flank Rear flank & Cod

Steer A

Steer B

Steer A Steer B

Market Beef Evaluation: Muscle Indicators Loin Quarter/ Rump Forearm Stifle

Live Cattle Evaluation u Weight u Dressing Percent u 12th rib fat u Ribeye area u KPH u Quality Grade u Yield Grade

Weight u Live or Carcass u Live Weight range u 900 lb to 1500 lb u Avg: 1200 lb u Carcass Weight range u 550 lb to 950 lb u 750 lb

Dressing Percent u Proportion of live weight that ends up as carcass u Example: 1250 lb steer with a 775 lb carcass has a dressing percent of 62% u Range: % u Avg: 62%

Factors Affecting Dressing % u Gut Fill u Gut fill = Body Weight = Dressing % u Hide weight and/or mud u Hide wt = Dressing % u Muscle u Muscle = Dressing % u Fat u Fat = Dressing % u Dairy influence

12th Rib Fat Thickness u Highly correlated to retail yield u Predictor of total carcass fatness u Range:.15 in. to.80 in. u Avg:.40 u.25 in. considered minimum

Ribeye Area u Highly correlated with lean yield u Predictor of total carcass muscle u Dependant of carcass weight u Range: sq. in. u Avg: 12.5 sq. in. for 1150 lb steer u Rule of thumb: 1.1 sq. in. for 100 lb live wt

Kidney, Pelvic and Heart Fat u Internal fat as a percentage of carcass weight u Continental cattle will tend to have less than British cattle u Range: % u Avg: 2.5%

Quality Grade u Assigned according to amount of marbling and bone maturity u Most influential component of pricing u Range: Standard to Prime u Avg: Low Choice

Factors Affecting Marbling u Genetics u Age of cattle u Time on feed u Energy content of diet u Fat cover u Continental/ Brahman influence

Yield Grade u Calculated to predict yield of boneless, closely trimmed, retail cuts from the round, loin, rib and chuck u Based on 4 estimations u 12th rib fat u Hot carcass weight (HCW) u Rib eye area (REA) u Kidney, pelvic, heart fat (KPH)

Yield Grade u Range: 1 through 5 u 1 = Lean and/or Muscular; High cutability u 5 = Fat and/or Light Muscled; Low cutability u Avg: 3.0

Introduction to Market Lamb Evaluation

Lamb Evaluation: Fat Indicators Shoulder Breast Forerib Flank

Lamb Evaluation: Fat Indicators Base of leg/ Twist Dock Spine Loin Edge

Lamb Evaluation: Muscle Indicators Forearm Leg Stifle

Lamb Evaluation: Muscle Indicators Rack Loin Leg

Reading Top Shape

Live Lamb Evaluation u Weight u Dressing percent u 12th rib fat u Ribeye area u Yield grade u Quality grade

Weight u Live weight u Range: lb u Avg: 125 lb u Carcass weight u Weight of dressed carcass with kidney and pelvic fat removed

Dressing Percent u Percentage of live weight that ends up as carcass u Range: % u Avg: u 53% for shorn lambs u 50% for unshorn lambs

Factors Affecting Dressing Percent of Lamb u Pelt weight u Unshorn lambs will dress 1-5% lower than shorn u Fill u Muscling u Fat cover

Fat Thickness u Taken at the 12th rib u Normally adjusted up to a.1 inch due to body wall fat u Used in YG equation u Range: in. u Avg:.25 in. u Minimum requirement:.15 in.

Ribeye Area u Measured at 12th rib u Indicator of total muscle in carcass but not used in YG equation u Range: sq. in. u Avg: 2.5 sq. in.

Yield Grade u Predicts the yield of boneless, closely trimmed retail cuts from the leg, loin, rib, and shoulder u Only includes adjusted 12th rib fat thickness u YG = (10 * Adj. fat thickness)

Quality Grade u Predictor of eating quality based on three factors: u Maturity u Lean Quality u Texture u Firmness u Marbling u Conformation

Lamb Quality Grades u Range: Good to Prime u Avg: Choice u Majority of market lambs will grade Choice

Lamb Quality Grade u Superior conformation can compensate for inferior lean quality and vice versa u Good lean quality with Choice conformation = Choice u Prime lean quality with Choice conformation = Prime u To qualify for Ch or Pr, lamb carcass must have at least.10 in. fat covering

Primal Identification

Introduction to Market Swine Evaluation

Swine Evaluation: Fat Indicators Shoulder Loin Edge Ham/ Loin Junction Junction Flank ElbowPocket Jowl Seam of Ham Ham

Swine Evaluation: Muscle Indicators ForearmHam Loin Stifle

Weight u Live Weight u Range: 210 lb lb u Average: 250 to 260 lb u Carcass Weight u Weight of dressed carcass (hot or chilled) u Chilled 1.5% less than hot u Range: lb u Avg: 180 lb

Dressing Percent u Proportion of body weight that ends up as carcass u Example: 255 lb live weight hog with 186 lb carcass = 73% dress u Some variation in dressing % across plants due to slaughter procedures and time of carcass weight measurement (hot or chilled) u Range: % u Avg: 72%

Factors Affecting Dressing Percent u Gut Fill u Gut fill = Body Weight = Dressing % u Muscle u Muscle = Dressing % u Fat u Fat = Dressing %

Carcass Length u Measurment taken from the First Rib to the Aitch Bone u Not in calculations u Range: in. u Avg: 31 in.

10th Rib Fat u Used in % Muscle Formula u Range: in. u Avg.:.90 in

Last Rib Fat u Used in USDA Grade calculation u Range: in. u Avg:.80 in.

Loineye Area u Estimated at the 10th rib u Range: sq. in. u Avg: 5.5

Reading Top Shape

BF =.90 inches

Reading Top Shape BF = 1.5 inches

Reading Top Shape BF =.20

The End!