Why do cows become lame? &

What can we do for them

Charles Guard, DVM, PhD Ambulatory & Production Medicine

Cornell University Ithaca, New York

© 2015

Causes of Lameness

Metabolic

Trauma / Mechanical

Over wear

Infection

Genetics

• Pathophysiology

– Metaloproteinase

– Trauma

– Infection

• Risk Ractors

– Nutrition

– Environment

– Management

Pathophysiology

• Abnormal claw shape or overgrowth

• Internal pressure very high beneath caudal sole

• Pressure necrosis of corium

Schematic of weight

distribution when claws out

of balance – pressure

induced lesion in corium

Patophysiology

Metaloproteinase

–Collagenase activated by relaxin near parturition

–Activated by unknown factors associated with ruminal acidosis

–Diminished support of P3 within the hoof capsule

Pathophysiology

Internal trauma follows

–More movement of P3

– Injury of soft tissue & rupture of blood vessels

–Production of abnormal hoof keratin

–Hemorrhage

Pathophysiology – Sole Ulcer

– High pressure between P3 & sole horn

– Damaged corium does not produce keratin

– More complicated when sole is misshapen

– Healing is slow – requires removal of pressure

Ulcer in toe tip

High incidence with long distance

walking

Ulcer in typical site

High incidence in housed cattle

Ulcer in toe tip

High incidence with long distance

walking

Ulcer in typical site

High incidence in housed cattle

Pathophysiology – White Line

–Separation between wall & sole – loss of cap horn

–Separation between laminae & wall – chronic leads to deformed claws & wide white line

–Hemorrhage between wall & laminae – hematoma becomes sterile abscess

Early lesion of the white line

Tissue injury after bleeding between wall & corium

Linea blanca muy ancha – laminitis cronica

Laminitis chronica

Patofisiologia de Infeciones – Bacteria estan en estiercol y barro

– Alguna estan normalmente en rumen

– Pueden penetrar skin danado

– La inmunidad no ayuda contra dermatitis pero importante in flemon

Dry lots are not dry everywhere

Sometimes it rains in the desert & feed lanes not cleaned

Risk Factors for Lameness Nutrition

• Ruminal acidosis • Diet formulation + Effective fiber

• Timing of feed delivery

• Access limitations

• There’s no nutritional magic bullet

• Cows with low Body Condition Score have thinner digital cushions – greater risk for sole ulcer

Effect of pH on ruminal acid production

Feeding grain in the parlor – slugging

Penn State Forage Particle Size Separator

Cows want to eat when returning from milking

Frequent feed pushup & some refusal at 24 hr

These dry cows had to fight for each bite

Environment

• Cows do not become lame lying down

– More time standing = more lameness

– Cow comfort in freestalls

– Overcrowding??

• Long distance walking or very abrasive floors can wear hooves faster than produced

• Heat stress

– More comfortable – more time lying

Effect of moisture on sole horn dynamics

Wet – thick and flat Dry – thin and concave

Good stall utilization

“Perching” when the stall has limiting dimensions

Overtrimmed?

NO! Sand on the floor from the beds was very abrasive

Exposed corium

Management Choices

• Overstocking

– Cows compete for beds and food

– More standing & more acidosis

• Parlor capacity

– Time away from bed & food – forced standing

• Time in lockups

• Grouping policies

• Transition cow issues

130 % capacity

100 % capacity

Milk price 2X – cow numbers 3X

Milked as 1 group in same parlor Poor performance & lameness disaster

Hoof Trimming very important

Quter claw

Inner

claw

Tip

Tip

Quter claw Tip

Inner

claw

Tip

After claw trimming

Before claw trimming

Veterinary Roles

Farm worker/owner interactions

• Treatment training

• Detection training

• Motivate for improvement

Lameness & Welfare

• Detection and action

• Appropriate therapy

– Pain control

• Prevention

• Detection

– Published evidence of poor performance

– Wide variation from farm to farm

• Why is performance so poor?

– Motivation

– Training

– Inefficient facilities

• What can be done?

Lameness & Welfare

Lameness & Welfare - Detection

• What can be done?

– Triaining of animal caretakers

– Motivation by education about financial consequences of lameness

– Education of farm advisors

– Technological fixes • Daily milk recording – deviations from rolling averages

• Activity monitoring – low activity scores

• Force plate diagnostics

• Video motion analyses

Lameness & Welfare - Detection

Lameness & Welfare

• Treatment of lame individuals

– Training & experience of those performing the task

– Limitations of facilities & therapeutic tools

– How many herds have the capacity to respond now ?

Facilities for treatment are essential for efficient care

Questions?