Ysh conformation and soundness2010 nov 2012

www.nixonequinevets.com

YORKSHIRE SPORT HORSE [SHB OF GB]

CONFORMATION AND PERFORMANCE

JANE NIXON MA, VET MB, BSc, MRCVS.

www.nixonequinevetconsultancy.com


The Horse

Some pertinent evolutionary facts

It is a Herd animal Galloping animal

Chased ‘prey’ species. Fright Flight (not fight!) Defender rather than an aggressor Single limb bone column: on Tip Toe

Pedal bone in horn capsule, the hoof

Grazer so requiring large head long neck capacious digestive system

Four legged, one at each corner, with no collar bone powerful hindquarters


As a prey animal the wild horse had to be Readily aware Quick off the mark Agile, fast and balanced in asymmetric gaits Quick to return to grazing composure

As a domesticated horse the Fright and Flight had to be trained (converted) into Alertness Responsiveness to aids, (biddable) Capable in all gaits (increasing speed and agility) Not stressed under saddle Fit to do and to recover


80% of propulsion comes from the hindquarters Hamstring and pelvic muscle power Top line muscle power to lift forequarter

“come up in front” Good shoulder / pastern line Saddle room for shoulder blade sweep

Always view from both sides

Growth to maturity is judged by final height at withers

Brisket, ribs, vertebrae & dorsal processes later

Limb bones to elbow close around 2 years

This age of this varies with breed

Ponies usually earlier than warm bloods


The Horse’s outline - Points are those of the skeleton

The surface areas – the jargonese description or name of the various parts The “points”

The landmarks at protruding parts of bones usually at a joint Visible and palpable Obesity does not hide the points


The skeletal top line and the bird’s eye views show areas of bone available for optimal muscle attachment. i.e.

Flat of ribs Side of dorsal processes Lateral processes of lumbars Flat of upper hind limb bones

Ham string and thigh muscles “size”


Fore Quarters Hind Quarters

No collar bone Bony Attachments


Scapular range

Shows the different positions assumed by the blade bone during the flexion and extensions of the limb


AT MATURITY

Balanced fore quarter Balanced Hindquarter


A balanced horse at grass

Able to graze without compromise of forelegs


Conformation > Soundness, ability, durability

Based on underlying, genetically determined skeletal framework (eg Skeletal “top line”)

Unalterable after maturity

Can only be ‘managed’ by breeding


Conformation is (constant and) fixed

However there are 3 variables which can be managed

I. CONDITION

II. HOOF BALANCE

III. DENTAL ARCADE BALANCE

All 3 of which can give a false impression of altered conformation and action


Conformation must not be confused or interchanged

with condition


Condition

in the “furnished” animal

reflects

muscle development between bones – fittening

fat deposition throughout- nutrition at varying

levels

It is weighable and contour measurable - profile/scoring

It is manageably variable and gives the effective top line


A “Furnished” Horse

It should “fill the eye”


“ANIMAL LOVERS UNABLE TO RECOGNISE PORTLY EQUINES”

WORLD HORSE WELFARE CHARITY POLL

i) 50% could not recognise pictures of overweight horses and many did not view condition as a welfare threat

ii) Thin horses often the correct weight, but looked thin compared to overweight field companions

VETERINARY TIMES JANUARY 25TH 2010

JUDGES: Go National Hunt racing to see fit horses


FAT DISTRIBUTION

UNFIT HORSE FAT FILLS IN BETWEEN MUSCLE GROUPS

↓

SMOOTH ROUNDER APPEARANCE

↓

FIT HORSE FAT IS REDUCED

↓

DEVELOPED MUSCLES STAND OUT


HORSE WITH GOOD CONFORMATION WILL/SHOULD

BE EXHIBITED IN CONDITION SUITABLE FOR JOB IN HAND

THOSE HORSES WITH WEAK CONFORMATION ARE MORE LIKELY TO BE EXHIBITED TOO FAT IN ORDER TO HIDE

FAULTS

I.E FAT HORSE IS INDICATION OF CONFORMATION PROBLEM


THE FEETThe hoof wall is modified skin (epidermis) thus

It is constantly growing down from the coronary band

Coincidentally worn down or trimmed

The whole hoof as judged at weight bearing should be balanced front to back, side to side, to give level foot fall

Should be trimmed to conformation of the individual limb

It is subject to distortion by torque from action due to poor conformation and/or foot balance


MEDIO- LATERAL INBALANCE


LEFT FORE FROM BEHIND

INSIDE

OUTSIDE

OUTSIDE

INSIDE


Well balanced foot Unbalanced foot

How to assess foot balance, left and right handed farriers


Conformation of Dental Arcade

THREE-POINT BALANCE PLUS EXCURSION

Three-point balance refers to the correct function of:-

1. The incisors

2. The molars

3. The mandibular (jaw) joint

Three-point balance allows normal jaw movements to take place and is achieved by:-

The removal of hooks The removal of sharp points which

develop on the outside of the upper and the inside of the lower premolars and molars

Adjusting the line of the incisors


Conformation of Dental Arcade

A purebred horse shows better conformation of the lower molar dental arcade fitting with the upper dental arcade than a crossbred horse.

Crossbred horses are more likely to have aberrant dental arcades with regard to the width, length and contours of the top and bottom jaws.

The angle of the head on the neck also makes a difference as to the fitting of the lower jaw to the upper jaw.

The factors alter the acceptance of the bit & the consequential muscle development & action of the horse


CONFORMATIONAL FAULTS

Does not fill the eye on 1st appearanceUnbalanced


NECK

Hollow in front of withers dorsal spinal ligament

– weak build up ventral muscles

Crest fat laminitis


THE BACK

WITHERS HIGHER THAN CROUP

→ Horse built upwardly

→ Easier to transfer weight to hindquarters

→ Trotters → Highest Speeds Achieved with Wide Short Thorax


BACK CONFORMATION AND PERFORMANCE

ADVANTAGE FOR CONFORMATION

Jumping Ability HEIGHT AT WITHERS

(Holmstrong 2001 Sweden) LENGTH PELVIS

NECK LENGTH

Dressage Ability Longer Backs than Jumpersas greater required

suppleness


BACK Jumper’s bump SI disease Long back More flexible

but

Weak → S I disease Roach back Sway back caudal 1/3 foot

pain

Shallow girth poor lung capacity Short back kissing spines

lumbar spine pain Slack loins SI disease

CONFORMATIONAL FAULTS


LONG BACK – More Flexible →SI Disease


ROACH BACK - Unsightly but not usually a problem


SWAY BACKCause of 1/3rd of Foot Pain


SHORT BACK – Kissing Spines


“SLACK LOINS” → SI disease


SHALLOW GIRTH

POOR LUNG CAPACITY


Good horizontal surface for saddle panels Weak

Slab Sided

Narrow Pelvis

Ribcage


THE FORELEGS

MAINTENANCE OF RHYTHM IN ALL PACES IS FUNDAMENTAL

LONGER LEGS →

i GREATER VARIETY IN STRIDE LENGTH

ii EXTEND MORE EASILY WITHOUT RAISING FREQUENCY OF STRIDE


THE FEET 1

SLIGHTLY ODD FRONT FEET

ESPECIALLY HEEL DEPTH

NO HEEL SUPPORT

WEAK HOOF CAPSULES

SIGN OF LAMINITIS

UNEVEN HEEL DEPTH → Uneven scapular height → Asymmetrical Shoulders re: saddle fit


THE FEET 2

NAVICULAR SYNDROME

LATEST RESEARCH DR S DYSON 2011

FIN AND FRESIAN HORSES LOW FLAT AND

CONVEX

DUTCH WARMBLOODS HIGH CONCAVE AND

UNDULATING

* More Research required into sensory nerve supply of the Navicular Bone. The syndrome does not seem to be related to foot shape!


SHOULDERS

Breed susceptibility to

overloading laminitis

poor saddle fit

Asymmetrical scapular cartilage difficult to fit saddle


ALL rotational and angular limb deformities out 8/10 rule

Overdeveloped muscles

indicate lameness behind

The Competition Horse conformational faults


NORMAL


BACK AT THE KNEE


Back at the Knee

Normal

BACK AT THE KNEE


BACK AT THE KNEE


FAULTS PREDISPOSING TO SPLINTS

Offset Knees Bow Legs Knocked Knees


THE HINDQUARTERS

The flatter the pelvis → More muscle → Greater strength and flexibility

STRAIGHT HIND LEGS → Unable to come under the horse

ACUTE HOCK ANGLE → Less able to carry weight

TARSAL VALGUS → Risk of Pelvic fractures


Quarters width should be parallel with thighs

HINDLEG

The Competition Horse conformational faults

NORMAL HOCK


HINDLEG CONFORMATION FAULTS

Straight Hocks

PREDISPOSED TO HIGH SUSPENSION DISMITIS

AS SEEN IN ANDULASIAN AND PASAFINOS


HOCK CONFORMATION

Cow Hocks

Pre-dispose to Pelvic Fractures

Sickle Hocks

Pre-dispose to Curbs


CURBANATOMY APPEARANCE


DEFINITION OF A CURB

COMPLEX OF SOFT TISSUE INJURIES ON BACK OF THE HOCK JOINTS

CONFORMATIONAL BONY ABNORMALITIES AND/OR INJURIES MAY MIMIC AND CONTRIBUTE EVENTUALLY TO CURB FORMATION

CAUSING UNDER PERFORMANCE AND LAMENESS


PASTERNS

SLOPING

→ OVEREXTENDED FETLOCK

→ STRAIN UP THE WHOLE OF THE BACK OF THE LEG TO THE PELVIS AND BACK

UPRIGHT

→ JARRING OF JOINTS ESPECIALLY FETLOCK → ARTICULAR AND TENDINOUS WINDGALLS


HIND FEET BALANCE

MORE IMPORTANT THAN FORELEGS BECAUSE HIND LIMBS ATTACHED TO AXIAL SKELETON AT SI JOINT

LONG TOE/LOW HEEL → SLOWS BREAKOVER → PELVIC PAIN

MEDIO LATERAL INBALANCE

→ HIND LIMB TORQUE

→ PELVIC ASYMETRY

→ BACK PAIN


DISCIPLINE INDUCED ORTHAPAEDIC RISK (AHT 2006)

S.J. ↑ INJURY SOFT BELOW FETLOCK) REPEATED STRAIN ON SOFT FORELEGS ) LANDING OVER HIGH FENCES

DRESSAGE ↑ HINDLEG HIGH SUSPENSORY ) EXTRAVAGANT DESMITIS ) MOVEMENT AND ) COLLECTION

GOOD CONFORMATION WILL DECREASE THE RISK


Examples of conformation faults causing multifactorial problems in the Competition Horse


HEAD CONFORMATION → JAW JOINT PAIN → One sidedness → Head Tilt → Uneven back muscle development → Poor saddle fit → Hind leg lameness


Heel of one front foot deeper than the other

High heeled foot → ↓ Shoulder blade → Poor Saddle fit

↓ ↓

→ Suspensory ligament pain → Uneven loading of back

↓ Hind leg lameness


Straight hind leg conformation → Upward fixating patellla → Gaskin MM → Asymmetrical pelvis

→ S I Pain → ↓ Impulsion → Forehand M M →Foreleg lameness


Equine Development and

Welfare

is dependent upon

EDUCATION &TRAINING


‘TO MEASURE IS TO KNOW’

What is NOT new ;

BALANCE

1 routine monitoring for early identification of problems.


BALANCE

2 monitor rider position

Forehand = fluidity //hindquaters =stability


anytime

What IS new ;

/pacing

Fairfax girth


THANK YOU FOR YOUR ATTENTION

please phone 07713342416 anytime

ANY QUESTIONS PLEASE?

www.nixonequinevetconsultancy.com

Ysh conformation and soundness2010 nov 2012

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Transcript of Ysh conformation and soundness2010 nov 2012