Course: Principles of AFNR

Unit Title: Sheep Selection TEKS: 130.2 (C)(12)(D)

Instructor: Ms. Hutchinson

Objectives:

After completing this unit of instruction, students will be able to:

A. List important areas to think about when selecting sheep;

B. Describe what to look for in structural correctness;

C. Explain why we need a structurally correct mouth;

D. Explain what type of performance data we look at when selecting for ewes;

E. Select the top 5 ewes when looking at the performance data for 8;

F. List the fleece characteristics to look for when selecting sheep;

G. Explain 5 ideal characteristics when judging market lambs;

H. Describe what the hindsaddle is;

I. Explain how to handle a lamb;

J. Describe a lamb that is too thin;

K. Describe a lamb that is correctly finished;

L. Describe a lamb that is over finished;

M. Explain how much an ideal market lamb should weigh; and

N. Label the wholesale cuts of lamb.

Interest Approach:

By being able to select quality sheep by visual inspection, the producer, breeder, and

consumer all benefit. Discuss ways in which the student and their families will

benefit.

Selection principles apply to agricultural student SAE projects. Encourage students

in the class who are maintaining sheep enterprises to discuss these projects with the

class.

Curriculum & Instruction:

Curriculum Select for…

Lamb or mutton production Wool production Feedlot Market (including show lambs)

Meat Production

Heavy weaning lambs of acceptable grade and type

Wool Production Clean weight and quality fleece are more

important Feeder Lambs

Desirable type and quality, health and vigor, and performance in the feedlot

Market Lambs Conformation, finish, and quality and yield of

carcass

A. List important areas to think about when selecting sheep;

Basic Factors for Selection:

Body conformation and wool Production Records Pedigree Health and Vigor

Other Important Areas:

Structural Correctness Frame Capacity Body composition Head Neck Shoulders

Instruction

PPT Slide 4-6 What are the decisions we need to decide before we start selecting our sheep? PPT Slide 7-17 What are the basic factors for selection?

Mouth Soundness The profitable breeding sheep is structurally and reproductively sound, highly productive, and can gain rapidly and efficiently. Many of the characteristics to consider when evaluating breeding cattle and swine are applicable to breeding sheep. This is also true of the market lamb areas of emphasis on muscling and leanness.

B. Describe what to look for in structural correctness; Structural Correctness:

Legs should be straight, strong, and set wide apart on the corners of the body

Walk with a long, free stride Allows them to adapt to range conditions

Long, sloping shoulder, level rump, and correct positioning of the feet and legs

Allows for freedom of movement Frame:

Important genetic factor Economical to maintain moderate-sized ewes

Breed these ewes with larger frames rams to get market lambs of a desirable size and weight

Capacity:

Sprung in upper rib region and deeply ribbed Stand wide and have ample width through the chest

floor Excess fat and condition creates an illusion of increased

body capacity

Describe a structurally correct lamb.

Describe correct body capacity in a lamb.

Body Composition: Heavily muscled with minimum amount of fat cover

Good body composition and strong eye appeal Desirable body composition for breeding lambs is the

same for market lambs

Head, Neck, and Shoulders:

Late maturing sheep have relatively long neck and head Broad forehead and ample width between eyes Ewe’s head should be more refined than a ram’s

Ewe Ram

Muscled, yet join neatly with top and blend in smoothly with the neck

Coarse, prominent shoulders can cause lambing difficulties if inherited by offspring

C. Explain why we need a structurally correct mouth;

Mouth Soundness:

Sound mouth and normal jaw Jaw should meet squarely and the incisor teeth in lower

jaw should be centered on the dental pad in the upper jaw

Jaw defects are highly heritable! May prevent gathering adequate forage

Jaw Structure:

Why should we care about a sound mouth and normal jaw?

D. Explain what type of performance data we look at when selecting for ewes;

Female Selection:

EPDs and Performance Records are not used extensively in the sheep breeding industry

Performance data may be used in Career Development Events

DOB, Weaning Weight, Type of Birth & Rearing, fleece weight and spinning count

Weaning Weight – indicator of growth and feeding efficiency

Type of Birth – Prediction of fertility Type of Rearing – reared alone or with rearing mates

because twins are preferred to single births in most sheep operations, the listing of multiple births is desirable.

E. Select the top 5 ewes when looking at the performance data for 8;

Pick the top 5 Ewes:

4, 5, 6, 7, and 8 Fleece Quality Evaluation:

Fleece quality is not important for market lambs Breeding sheep production 2 products: meat, and wool

PPT Slide 18-20 When do we normally pay attention to performance records of sheep? What information can you find in a sheep’s performance record?

PPT Slide 21-26 What two products can we raise sheep for?

Medium-wool fleece should be evaluated for presence of any black fiber or kemp

Kemp is a chalky, white fiber that is hollow and does not dye well

F. List the fleece characteristics to look for when selecting sheep;

Fleece Characteristics:

Fineness Staple Length Belly Wool Density General Appearance Face wool

Fineness, Length, Belly Wool:

Coarse fibers at shoulders and rump Look for uniformity of fleece throughout!

What is kemp? Why do we not want any black fibers or kemp in the wool?

What fleece characteristics do we look for?

Where is our lowest quality wool found on a sheep?

Meet staple length requirements! Fine-wool = 2.75inches or longer

Belly wool is short and less desirable Undesirable if this wool carries up high on the

side Open fleece of belly and work upward on the

side to detect how far the belly wool carries Density, Appearance, and Face Wool:

Density is determined by opening the fleece and handling the wool

Number of fibers per square inch of body surface

Tip of fibers will probably be dirty, but the remaining should be bright, white and free of any colored fibers or kemp

Open face ewes are more desirable Extra management with too much wool over

the eyes Evaluating and Judging Market Lambs:

Major attention at: Muscle Finish Length Type

Size and evidence of growth rate should be considered Parts of a Lamb:

G. Explain 5 ideal characteristics when judging market lambs;

Ideal Characteristics of a Lamb:

Why do we not want face wool?

PPT Slide 27-35 Where is my our most attention at when evaluating and judging market lambs?

Market Lambs:

Major Consideration: Muscle Balance Correctness of finish

“Ideal” lamb is heavily muscled and has a minimum amount of fat

Thick and meaty through: Loin Rump Leg regions

H. Describe what the hindsaddle is;

Hindsaddle should have a high percentage of a sheep’s

weight Loin and leg combined Highest priced retail cuts

The loin should be deep, as well as wide, and the leg should be expressively muscled.

Market:

Trim in breast, middle, flank, and forerib Fullness in these areas indicate excess fat and condition

What are the ideal characteristics of a lamb?

Head

Neck

Shoulder

Chest

Back

Loin

Rump

Legs

Body

finish

Describe an “ideal” lamb.

Where is most of the sheep’s weight suppose to be?

Rib and loin should have a muscular shape to its top

I. Explain how to handle a lamb; Handling Market Lambs:

Allows to properly assess the amount of muscling and finish

Excess fat is undesirable! Always keep fingers together to get the proper “feel” Start at the front and handle down the top towards the

rear of the lamb Feel how much finish or fat cover is over the loin Measure actual width of top to determine amount of

muscling or loin eye muscle More width and expression, coupled with leanness =

desirable!

Every lamb should be handled in the same manner to make proper comparisons between each lamb.

J. Describe a lamb that is too thin; Too Thin:

Very prominent of sharp backbone Each rib will be sharp and very easy to feel

Explain how to handle a lamb. What are we looking for while handling market lambs? PPT Slide 36 PPT Slide 37 PPT Slide 38-40 Describe a lamb that is too thin,

Hollow feeling between each rib

K. Describe a lamb that is correctly finished; Correctly Finished:

Backbone can be easily felt but is not “sharp” Ribs can be felt but are not sharp to the touch No hollow feeling between the ribs

L. Describe a lamb that is over finished;

Too Fat:

Handle very smooth over the top with the backbone not easily felt

Ribs can be felt, but it will not be easy to distinguish between each rib

When handling for muscling, primary attention should be given to the length of the hindsaddle and rump and the circumference of the leg.

When measuring the hindsaddle, check the length from the last rib to the base of the dock.

Describe a lamb that is correctly finished. Describe a lamb that is too fat.

PPT Slide 41 PPT Slide 42

Also check the length, width, and depth of loin, as well as, the length and width of the rump.

The leg should be handled for depth and volume of muscle, making sure to measure the leg’s circumference.

M. Explain how much an ideal market lamb should weigh; and

Live Weight:

Weights range from 100 to 160lbs Desirable market lambs weigh between 120 and 135lbs Desirable to gain at a fast rate, yet maintain acceptable

leanness at the “ideal” slaughter weight

N. Label the wholesale cuts of lamb.

PPT Slide 43 PPT Slide 44 How do you measure the circumference of a sheep’s leg?

PPT Slide 45-50 What is the ideal market weight?

Students are to draw and label the diagram above in their notes. Wholesale Cuts:

Need to be free of excess fat More muscle = more total marketable product = more

$$$ A Muscular and Correctly finished Lambs:

Label the wholesale cuts of lamb.

An underfinished and poorly muscled lamb:

1. Weak-topped

2. Smaller-framed

3. Shorter-sided

4. Sloped rump

5. Flat muscle pattern,

lacks expression

1. Narrow over top

2. Less expression of

leg muscling

3. Less total volume of

muscle (concave

appearance)

Estimating Age:

Udders:

Two halves that are free of knots Teats adequate in size, not too large for lambs Not pendulous so that it could be injured by the legs

and brush Testicles:

Free of knots Evenly sized Descend from body wall

Students will be split into groups. I will place a “placing class” of lambs on the screen for them as a group to decide how they would place the class and why. After giving the groups about 15 minutes to look over the sheep we will go around the room

PPT Slide 51 How should the teeth look for a lamb that is about 18-24 months of age?

PPT Slide 52-53 Describe a ewe’s udders. Describe a ram’s testicles.

hearing the reasons behind why each group picked the sheep they choose. I will then tell the students the way I placed them and why. I will take a grade on this assignment, and students who give answers like “because it’s pretty” or any other response that is not a dignified answer their grade will reflect on it. I will help the students if they are stuck on where to start looking at first when placing their class. If this lesson is done before the SAE projects are sold, I will bring live lambs to the classroom so the students can practice feeling a lamb and selecting a class in that manner as well. Independent Practice: Students will be given another set of lambs to select and they will write down their placing and the reasons for the way they placed the sheep.

Review & Instruction:

Objectives will be reviewed before examinations. Exams will be developed based on objectives as

taught in class.

Instructional Support:

A. References

a. IMS Online Curriculum

b. Colorado Agriscience Curriculum

c. www.livestockjudging.com

B. Teaching Aids & Equipment:

a. Sheep Selection PPT

b. Sheep Selection Student PPT

c. Livestockjudging.com market lamb classes

d. Sheep Selection Test Review

e. Sheep Selection Test

C. Facilities:

a. Agriculture classroom