Observations on Stunning Plac

in Cattle

J.K. Shearer DVM, MS.

Professor and Extension Veterinarian

Department of Veterinary Diagnostic and Production

Animal Medicine

Iowa State University

Ames, IA, 50011

JKS@iastate.edu

AMI Foundation

Animal Care and Handling Conference

March 25-26, 2010

Kansas City, MO
Guidelines for selection of the most appr

site for conducting euthanasia in cat

“The point of entry should be at the intersectionof two lines each drawn from the inside corner o

the eye to the base of the opposite horn (or

slightly above the ear in cattle without horns).

Practical Euthanasia of Cattle, The AABP Brochure on Eut
Evaluation of 3 Anatomical Sites 

Conducting Euthanasia in a Holstei

1. Medial canthus (inside corner) of the eye t

the top of the ear (opposite side)

2. Medial canthus (inside corner) of the eye t

the base of the horn

3. 1 1⁄2 inches above the intersection of #2
Inside corner of the eye to top of th
Inside corner of the eye to top of t

Bolt held perpendicular to the forehead

Brain

Nasa

Spinal Cord

Bolt enters to far forward misses brain tissue comp
At the intersection of 2 lines each draw

the inside corner of the eye to the base 

horn on the opposite side
Inside Corner of the Eye to th

Base of Horn

Pin held perpendicular to the forehead

Brain

Spinal cord

Direction of pin travel wmassive brain destructiif pin is oriented slightly foramen magnum
Inside Corner of the Eye to th

Base of Horn

Pin angled toward the foramen magnum

Significant damage to bbut angling pin toward tmagnum as shown not a

Brain

Spinal cord
Site: 1 1⁄2 inches above the intersection o

each drawn from the inside corner of th

the base of the horn on the opposite sid
Inside Corner of the Eye to th

Base of Horn (1 1⁄2 inches abov

Pin held perpendicular to the forehead

Brain

Spinal Cord

Effective stunnlower site is pr
Path of the bullet used to kill thi

Bullet entry site

Bullet appears to have missed the brain completely

Bullet entry site

Skull – left half 
Anatomical sites in an AngusXHereford Steer

3 Anatomical Sites

1. Medial canthus (inside corner) of 

the eye to the top of the ear (opposite side)

2. Medial canthus (inside corner) of 

the eye to the base of the horn

3. 1 1⁄2 inches above the intersection 

of #2
Inside corner of the eye to top of 

opposite ear

Brain

Pin misses braincompletelyAngusXHereford Steer
Inside corner of the eye to top o

opposite ear

AngusXHereford Steer Holstein Cow
At the intersection of 2 lines each draw

the inside corner of the eye to the base 

horn on the opposite side

Pin is rostral (forward), but stun site correct

AngusXHereford 
At the intersection of 2 lines each draw

the inside corner of the eye to the base 

horn on the opposite side

AngusXHereford Steer Holstein Co
Anatomical Sites for Proper Stun
Anatomical location for proper 

stunning of cattle is on the intersection of 2 lines each drawn from the top of the eye to the base of the horn on the opposite side
Alternative Method for Site Sele

• Approximately 1 to 1 1⁄2

inches above the

intersection of 2 lines

each drawn from the

inside corner of the eye

to the base of the

opposite horn

From Shearer and Nicoletti, Procedures for E
In Summary,

• Many of the current recommendations 

selection of the most appropriate anato

site for conducting euthanasia in cattle incorrect

– The site most commonly used is too low a

many cases misses the brain completely
In Summary,

• Anatomical location for proper stunnin

cattle is

– on the intersection of 2 lines each drawn 

the top of the eye to the base of the horn 

opposite side or,

– 1 ‐ 1 1/2 inches above the intersection of 

each drawn from the inside corner of the 

the base of the opposite horn

• There may be breed differences but use of ab

guidelines should provide consistent results
Special Thanks to Dr. Mike Sieme

and Cargill for their assistance wi

this presentation.