Dehorning-Cornuectomy-in-Large-Animal.ppt

Veterinary Medicine

1. Dehorning (Cornuectomy)

2. Horns are removed for several reasons
Dangerous weapons
Damage can done by fighting
Feedlots typically pay less money for
horned animals
Can cause damage to the facilities
Horns may also become tangled in fences,
branches, and other objects
It is the best interest of the animal to
remove the horns at the early age

3. Longitudinal cross-section of a horn, showing extension
of the frontal sinus of the skull into the horn. Dehorning,
which is performed at the base of the horn, exposes the
sinus

4. Surgical Removal
Dehorning is usually performed on a conscious, sedated
animal with local anesthesia for control of pain.
Needle placement for desensitizing
the cornual nerve in the bovine. The
cornual nerve follows the temporal
ridge to the base of the horn
Anesthesia for dehorning in the goat.
A,Needle placement for desensitizing the
cornual branch of the lacrimal nerve.
B,Needle placement for desensitizing the
cornual branch of the infratrochlear nerve

5. Dehorning

6. Chemical Cautery
Example Procedure for Dehorning
1. 10 min before dehorning calves are
sedated with xylazine (0.2 mg/kg IM).
2. Hair is clipped around each horn bud, a
thin film of caustic paste (2 cm diameter)
is rubbed into the scalp until each horn
bud is evenly coated, and a ring of
petroleum jelly is applied around the paste
to prevent spreading.
3. Calves are allowed to rest sternally until
recovered from sedation.

7. (A) Well-healed scabs after caustic paste dehorning
(B) Over-application of caustic paste can damage the calf.

8. Dehorning (cont’d)
Tube spoon or calf dehorner
Use on calves 2 months or younger.
Procedure
Restrain calf in head gate or chute.
Scrub around horn area with an antiseptic.
Place the cutting edge of the instrument around
the base of horn button, including one eighth
of the skin around the horn.

9. Dehorning (cont’d)
Twist the tube each way; must cut 1/8 to 3/8 of an
inch deep. Push down toward the jaw, and spoon
out the horn.
If bleeding is excessive, take forceps and pull the
artery straight out so that it breaks in the soft tissue
of the head.
This will cause blood clotting.

10. Dehorning (cont’d)
•Bell-shaped dehorners
–Electric or hot iron
–Bell dehorners come in different sizes
–Done on calves under 4 months of age
–Procedure
•Restrain in chute.
•Apply the hot iron over the bud to the base also
covering a ring of hair.
•Leave on until a copper-colored hide appears around
the horn (usually 10 to 20 seconds)

11. Dehorning (cont’d)
Barnes dehorner –Lever type dehorner
Large beef herds: Dehorning not done until
weaning around 7 months of age
Procedure
Barnes dehorners lift the horns out by the roots
and crush the blood vessels (little to no blood).
Restrain animal in chute.
Place dehorner with handles together over the
horn.
Pictures navies

12. Dehorning (cont’d)
–Remove also 1/4 to 1/2 inch of skin around the
horn base.
–Spread handles apart quickly, and remove the
horn base.
–The horny tissue must be removed or the
horn may grow back.
–Pull up on bleeding arteries with forceps, and
twist and pull until it breaks.
–Use some type of antiseptic spray or solution
over the wound.

13. Dehorning (cont’d)
Keystone
dehorner: lever-
type dehorner
Larger horns
SE: hemorrhage,
fractures

14. Dehorning (cont’d)
Cosmetic dehorning
Used on show animals and expensive
breeding livestock
Best if done under one year of age; older
animals are harder to close skin
Procedure
Restrain animal in squeeze chute and secure head
to one side.

15. Dehorning (cont’d)
Clip hair around horns up to the ears and
the eyes.
Scrub area.
Perform nerve block.
Surgical site is given a final scrub.
Incision is made around the base of the
horn.

16. Dehorning (cont’d)
Incision is deepened until bone is hit.
Gigli wire is placed, and the bone is
sawed off.
Flush with solution to flush out the bone
dust.
Only one layer of skin is closed with
nonabsorbable suturesin a simple
continuous pattern.
Remove sutures in 2 to 3 weeks.

17. Dehorning
1.Surgical preparation
2.The skin is incised approximately 1.5 cm from the base of the horn (incorporate all germinal
or nonhaired epithelium in the horn removal to lessen the likelihood of regrowth or scur formation)
3. Assistant supporting the goat's head
4. Gigli wire is seated under the caudal aspect of the skin incision on one side and the horn is sawed off
in a cranial direction
5. Hemostasis can be applied to control hemorrhage from the superficial temporal artery
6. Remove all blood clots and bone chips/dust from the frontal sinuses
7. Bandage (nonadherant dressing (Adaptic®) covered with antibiotic ointment): EOD –week 1; SIW until sinuses’s close
8. Flunixin should be administered for 2-3 days post-operatively and antibiotic administration is at the discretion of the
surgeon. Tetanus antitoxin (500 IU) should always be given and a dose of a CD-T bacterin can also be administered
to boost immunity.

19. Heat Cautery
This is he fast and almost bloodless method is
popular, specially in goat kids
The tip of the disbudding iron is shaped in an
open circle. When iron is sufficiently heated, the
tip is centered over the horn bud and applied
with circular “rocking” motion with light pressure
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