Introduction to Breeding Livestock Judging and Evaluation.

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Introduction to Breeding Introduction to Breeding Livestock Judging and Livestock Judging and EvaluationEvaluation

Introduction to Beef SelectionIntroduction to Beef Selection

Criteria for Beef SelectionCriteria for Beef Selection

Soundness Structural Reproductive

Volume and Capacity Muscle Skeletal Extension Femininity/ Masculinity

Ideal Beef HeiferIdeal Beef Heifer

Structural CorrectnessStructural Correctness

Correct joint angles Shoulder, knee, hock and pastern

Strong top Level rump structure

Hooks to pins Large, square foot Adequate bone

Structurally Correct HeiferStructurally Correct Heifer

Structurally Correct HeiferStructurally Correct HeiferLevel rump Strong top

HockAngle

ShoulderAngle

Knee &PasternSet

Structurally Correct HeiferStructurally Correct Heifer

Correct Structure: Rear viewCorrect Structure: Rear view

Straight StructuredStraight Structured

Incorrect Hip and Hind Leg Incorrect Hip and Hind Leg StructureStructure

LowPinSet

TooMuchSet to Hock

Volume and CapacityVolume 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 HeiferHigh Volume Heifer

Deep Fore &Rear Flank

Lacking Volume!Lacking Volume!

MuscleMuscle

Heavy muscled cattle are preferred if muscle pattern is long and smooth

Tight, round muscle can inhibit movement

Skeletal ExtensionSkeletal 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

FemininityFemininity

Females need to be refined through their shoulder, neck, and head

Vulvas need to be developed with correct udder structure

Correct FemininityCorrect Femininity

MasculinityMasculinity

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 MasculinityCorrect Masculinity

Importance of Testicle SizeImportance 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 Introduction to Live Animal EvaluationEvaluation

Introduction to Market Introduction to Market Beef EvaluationBeef Evaluation

Market Beef Evaluation:Market Beef Evaluation:Fat IndicatorsFat Indicators

Tailhead & Pins

LastRibs

Brisket

Foreflank

Rear flank& Cod

Steer ASteer A

Steer BSteer B

Steer A

Steer B

Market Beef Evaluation:Market Beef Evaluation:Muscle IndicatorsMuscle Indicators

Loin

Quarter/Rump

Forearm

Stifle

Live Cattle EvaluationLive Cattle Evaluation

Weight Dressing Percent 12th rib fat Ribeye area Quality Grade Yield Grade

WeightWeight

Live or Carcass Live Weight range

900 lb to 1500 lb Avg: 1200 lb

Carcass Weight range 550 lb to 950 lb 750 lb

Dressing PercentDressing 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 Thickness12th 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 AreaRibeye 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 MarblingFactors Affecting Marbling

Genetics

Age of cattle

Time on feed

Energy content of diet

Fat cover

Continental/ Brahman influence

Yield GradeYield 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 GradeYield Grade

Range: 1 through 5 1 = Lean and/or Muscular; High cutability 5 = Fat and/or Light Muscled; Low cutability

Avg: 2.5