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Conformation 101
SUSAN SCHOENIANSheep & Goat SpecialistUniversity of Maryland [email protected] - www.sheepandgoat.com
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An animal’s value is the sum of its performance and what it looks like.
Date of birth: February 15, 2015Type of birth: tripletType of rearing: tripletBirth weight: 10.0 lbs.Adj. 60-d weaning weight: 70 lbs.Adj. 120-d weight: 120 lbs.Post-weaning FEC: 600 epgScrapie genotype: RRBWT MMW
TWWT PWWT NLB NLW
-0.4885
2.0160
5.3883
7.5269
2252
1853
(NSIP) Estimated breeding values
What is conformation?Internet definitions• The shape or structure of
something, especially an animal.
• Structural arrangement.• A symmetrical arrangement
of the parts of a thing.• Visual aspects of an animal.
• What it looks like!
Why is conformation important?
• Elements of conformation are thought to be heritable.
• Animals that have conformation defects may have reduced productivity and/or longevity.
• Many conformation defects get worse with age.
• If physical traits are not positively selected for, they will be gradually lost.
• Animals with good conformation are valued and usually worth more money.
No one likes to look at ugly sheep!
Importance of conformation may differ according to purpose of flock.Registered stock
• Cull hard, especially males.
• Registered animals are representative of the breed and the means by which the breed is improved.
Show stock
• Cull hard, both sexes.
• Select animals with superior conformation.
• Show animals are valued for their conformation.
• The show ring is all about what the animal looks like.
Commercial flock• Establish
minimum standards.
• Hold rams to a higher standard than ewes.
• Not all conformation “defects” have a negative effect on performance.
• What is deemed acceptable varies.
What constitutes conformation in a sheep?• Mouth (teeth and bite)• Feet, legs, and hooves• Back, top line, shoulder• Volume and capacity• Substance of bone• Muscling• Frame size• Condition• Sex characteristics• Balance and eye appeal
Sound mouthBite (jaw alignment) Teeth
Jaw alignment (bite)• Properly aligned jaw
• Teeth should meet dental pad
• Sheep with jaw abnormalities may have difficulty nursing, eating and/or grazing.
• Bites rarely improve with age.
• Jaw defects are inherited.Cull both parents, if known (?)
• Diet can affect jaw alignment.
Jaw abnormalitiesOvershot (parrot mouth) Undershot (monkey
mouth)
Jaw abnormalities vary in severityDo you cull? Who do you cull?
Normal Slight defect 1-3 mm
Cull rams (?)Keep ewes
Severe defect >3 mm
Cull rams and ewes
Cull sires and dams
KHSI considers an over- or under-shot jaw to be a defect – but by how much?
Source: Visual Scores, Sheep Genetics, Australia
TeethMore of a consideration in mature animals.
• Sheep have 32 teeth: 8 permanent incisors on the upper jaw and 24 molars on the upper and lower jaws.
• The incisors are used to nibble grass.• The molars are used to chew the cud.
Incisors• A lamb is born with eight milk teeth at the front; a pair of milk teeth
is replaced each year starting with the pair in the middle.• You can tell the approximate age of a sheep by its (incisor) teeth.• Cull (don’t buy) sheep with premature loss of incisor teeth
Cull (don’t buy) sheep with with worn, broken or missing teeth (i.e. aged).
• Loss of incisor teeth is more problematic in grazing situations; is of less importance if sheep are fed concentrates.
Lamb Yearling Solid (full)
Broken Gummer
Molars• Sheep have 24 molars: 6 pairs of molars on each jaw.• Cull (don’t buy) sheep with overgrown, worn, or missing molar
teeth.As evidenced by impaction of food in cheeks, short, jerky jaw movements, fibrous feed protruding from corners of mouth, dropping of large wads of masticated fibrous food from mouth.
Image source: NADIS UK
Feet, legs, hooves•Move freely•Painlessly•Normal gait•Straight legs that
come out of each corner of body
•Stand squarely•Proper angle to
pasterns.•Healthy hooves
Front legs (side view)
Correct Calf-kneed
Weak pasterns(KHSI defect)
Buck-kneed
Source: http://www.danekeclublambs.com/SheepFeetandLegStructureTest.html
Pasterns
PasternsCulling decisions
20-40º
Slight defect Cull rams (?)Keep ewes
Slight defect Cull rams (?)Keep ewes
Severe defect
Cull rams and ewes
Severe defect
Cull rams and ewes
Source: Visual Scores, Sheep Genetics, Australia
Front legs (front view)
Correct Splay-footed(KHSI defect)
Pigeon-toed Knock-kneed
Source: http://www.danekeclublambs.com/SheepFeetandLegStructureTest.html
Rear legs (side view)
Correct Sickle hocked(KHSI defect)
Post-legged
Source: http://www.danekeclublambs.com/SheepFeetandLegStructureTest.html
Rear legs (rear view)
Correct Bow-legged
Cow-hocked(KSHI defect)
Source: http://www.danekeclublambs.com/SheepFeetandLegStructureTest.html
Healthy hooves• Free from disease• No abnormal growth• No excessive growth• Favor dark colored hooves
(?)
Back, topline, shoulder
KHSI• Neck: Strong, of medium
length: extends straight into the shoulder.
• Shoulders: Blend smoothly into the neck and back; shoulder blades have good width between and are level with or slightly higher than the back.
• Back: Strong, smooth, and broad.
• Weak shoulders or back are considered a defect by KHSI.
Volume capacity, spring of ribKHSI• Chest: Wide and deep enough
to provide ample room for good heart and lung capacity.
Slightly less width than hindquarters in females.
• Ribs: Well sprung, wide and deep.
• Abdomen: Large capacity for consuming forage and carrying lambs (bottom or side line should not necessarily be straight).
MusclingKHSI• Katahdins are a heavy-muscled (?),
medium-sized breed.
• Well-developed upper arm muscle in rams.
• Strong, smooth, and broad back.
• Loin long, wide, deep and well-fleshed.
• Wide and well fleshed rump; rounded appearance; deep in twist.
• Muscles of the thigh are thick, with obvious muscularity on the inner and outer thigh, carried down to the shank.
Select for adequate vs. superior?
Substance of bone• Thickness of the cannon bone of the front leg• Light bone structure is considered a defect in the Katahdin breed (KHSI).
Frame sizeheight (mostly) + length
• Katahdins are a medium sized breed (KHSI)• Mature weight (OSU Breeds of Livestock)
120-160 lbs. (ewes)180-250 lbs. (rams)95-115 lbs. (market wethers)
• Frame size is used to predict the size of the lamb when it is finished; larger framed lambs finish at heavier weights than smaller framed lambs.
• Frame size may influence the ease with which lambs are finished, especially on forage diets.
• Selection (especially single trait selection) for growth may lead to increased mature size.
• Large framed animals tend to have higher feed requirements, but lower maintenance costs than smaller framed animals (moderate: ideal?).
• There are differences among Katahdin breeders, with regards to the desired frame size, mature body weights, and finish weight of market lambs. What is the ideal size
Katahdin ewe?
Condition• Avoid sheep that are
overly fat or thin.• Use body condition
scoring to assess fat and muscle.
1. Emaciated (very thin)2. Thin3. Average 4. Fat5. Obese (very fat)
• Prefer BCS 2.5-3.5 for ewes
• Prefer BCS 2-3 for market-ready lambs.
Sex characteristicsRams should be masculine Ewes should be feminine
Testicles• Two testicles• Well hung• Free from disease• Similar size• Firm• Movable• Lumps• Deformities• Cryptorchid or monocryptorchid
(KHSI defect)
• Adequate size (Extremely small testicles are considered to be a defect by KSHI)
Ram age Questionable Satisfactory Exceptional8-14 months < 30 cm 30-36 cm > 36 cm> 14 months < 32 cm 32-40 cm > 40 cm
Teats and udder• Two normal teats• Equal size udder halves• Free from disease• No lumps, hardness• Good attachment• Two functional halves!• Scar tissue• Malformed teats• Low hanging udder• Oversized teats• Supernumerary teats
Missing or malformed teats are considered to be a defect by KHSI.
Balance and eye appeal
•How well the animal’s parts fit together.
•Straightness of lines•Proportionalism•Smoothness•Attractiveness
An animal’s value is the sum of its performance and what it looks like.
Date of birth: March 16, 2016Type of birth: quadrupletType of rearing: quadrupletBirth weight: 8.3 lbs.Adj. 60-d weaning weight: 46 lbs.Adj. 120-d weight: 77 lbs.Post-weaning FEC: 500 epgScrapie genotype: RR
BWT MMWT
WWT PWWT NLB NLW
-0.2985
3.0160
4.3583
2.5267
2551
2342
(NSIP) Estimated breeding values
SUSAN SCHOENIANSheep & Goat SpecialistUniversity of Maryland [email protected]
Thank you for your attention. Questions? Comments?