Chapter 16
Ovine and Caprine Surgery
“It’s not that I’m so smart, it’s just
that I stay with problems longer.” ~
Albert Einstein
Objectives
• basic differences between standing surgical procedures and
general anesthesia procedures.
• Prepare a sheep or goat for surgery.
• Assist and/or perform induction and maintenance of
anesthesia.
• Provide anesthetic monitoring.
• Manage the patient during recovery and immediate
postoperative periods.
• basic risks and possible complications associated with
anesthesia and surgery, and implement preventive measures
when indicated.
Key Terms
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Buck odor
Descenting
Elastrator
Fly strike
Hypoglycemia
Laparotomy
Malacia
Meningitis
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Supernumerary teats
Tetanus
Trocar
Urinary Calculi
Reading Assignment
Chapter 16: Sheep and Goat Surgeries
Surgery
• Similar to cattle
– NPO: Food - 12 to 24 hours; don’t withhold water
– Lambs and kids: consuming solid food material fasted for 2 to 4 hours.
– Fasting is not recommended in neonates.
• Low risk of regurgitation as rumen/reticulum not
functional
• Hypoglycemia is common
Local Anesthetic
• Sheep, and goats especially, are more
sensitive to lidocaine.
– May be toxic at 10 mg/kg (cattle > = 13 mg/kg)
total dose.
– Do not use in concentrations greater than 2%.
• Dilute to 0.5 – 1%
– lidocaine toxicity: muscular tremors,
severe depression, hypotension ,
occasionally convulsions
Blocks
• L block
– Most common
– A 18- to 20-gauge × 1 to 1 1/2 inches in length
– Procedure same as cattle
• Paravertebral block: don’t need trocar
– A 18- to 20-gauge × 1 1/2- to 3-in spinal needle
– Use 0. 2 to 5 ml of lidocaine per site
– Distal paravertebral approach: 20- to 22-gauge ×
1-in needle, 2 to 4 ml
Local Blocks
• Docking (~91 %), castrating (~78%), and
disbudding are management practices
routinely performed on sheep and goat farms.
• Maintaining a high standard of animal welfare
should
be a consideration in all decisions related to
docking, castrating, and disbudding.
Cornuectomy
Blocks (cont’d)
• Cornual nerve block
– Goats: Dual nerve supply
– Lacrimal nerve – cornual branch
– Depth: 1 to 1.5 cm
– A 22- to 23-gauge × 1-in needle
– 0.5 – 1 ml for kids; 2-4 ml adults
– Infratrochlear nerve – cornual branch
– Depth: 0.5 cm
– A 22- to 25-gauge needle
– 0.5 ml for kids; 1-3 ml adults
– Sheep are rarely dehorned.
– Lacrimal nerve – cornual branch
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
Blocks (cont’d)
• Intravenous regional analgesia (Bier Block)
– A 22- to 25-gauge needle
– Up to 10 ml of anesthetic
• Caudal epidural analgesia
– A 18- to 21-gauge × 1- to 1 1/2-inch needle for
caudal epidural
– Not > than 0.5 – 1 ml of 2% lidocaine/ 50 kg. body
weight of sheep and goat
General Anesthesia
• Same concerns as with cattle
• Inhalant gases
– Facemask induction < 150 lb
– Oxygen (3 to 5 L/min) is given for 1 to 2
minutes before introducing anesthetic gas
• Halothane – 3 - 4%
• Isoflurane – 3%
• Sevoflurane 4 – 6%
• Endotracheal: 10 to 12 mm in adults
– Heart rate: 80 to 150 beats per minute
• Pre – anesthesia: diazepam – ketamine - propofol
General Anesthesia (cont’d)
Long blade laryngoscope
Castration
• Usually done in week 1
– Urinary calculi
• Can wait till 5-6 months in pets to reduce
incidence of urinary calculi
• Castrate before sexual maturity
• Adults
– Hemorrhage
– Sedated
Castration
• Done in the same manner as calves
with a blade
• Age
– Goats and sheep: 2 to 4
weeks of age
– Pigs: 1 to 21 days of age
• Anesthetic
– None is needed for sheep, cattle, pigs, or goats
• Should give tetanus antitoxin to goat and sheep
• Can use antibiotics as preventative
• Sheep and goats can be banded (emasculator bands)
• 10 days later
(cont’d)
Emasculatone: spermatic cord
Emasculator bands
Castration – small ruminants
• Burdizzo emasculatome
• Crushes the spermatic cord
– which crushes the blood vessels
(thus depriving the testicles of
blood supply) and causing them to
shrivel up and die
• Don’t use cattle-size Burdizzo
• By six weeks of age
Newberry Knife
Dehorning
US: dairy goats cannot be registered/ shown if
they have horns
Disbudding: heat cautery
Dehorning (cont’d)
Tail Docking: Sheep
• Reasons
– Improve sanitary conditions: Wool gets saturated
with urine and feces
– Increase productivity in ewes: Tail will not get in
the way when bred
– Appearance: Show animals
• Age
– Before 2 weeks of age
– Can do it 24 hours after birth if lambs are big
Tail Docking (cont’d)
– Reasons to dock early
• Less trauma and stress
• Less bleeding
– Types of tail docking
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Sharp pocket knife
Emasculatone
Emasculator
Hot docking irons
Elastrator
Pruning shears
Tail Docking (cont’d)
• Procedure
– Place tail on firm base.
– Cut 1 inch from body.
• Closer can cause prolapse
– Force skin toward body so excessive skin will cover
end when done.
– Place the knife on the tail, and cut between the
vertebra with a forward and downward motion.
– Spray with iodine.
– Pinch dock between fingers, if excessive bleeding.
C-Section
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Left flank with the female in right lateral recumbency
The head should not be elevated
L block
Clip and surgical preparation
Neonates
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Clear the airways
Confirm pulse and respiration
Dry and warm
Treat the umbilical cord
• Close with multilayer suture
• Antibiotics and anti-inflammatories
Supernumerary Teats
• Serrated scissors
– Cut craniocaudal
Descenting
• Removes buck odor
– Rut : urinate head, beard, forelegs
• castration
– Primary scent glands
• Caudomedial base of each horn
• Performed at any age
• They may be removed during the dehorning procedure by
extending the skin incisions to include them.
• At other ages: Under sedation and local anesthesia
• Sutures can be used to close the skin
• Breeding females may reject males that lack this scent.
Disbudding: The electric iron is now being used to destroy the scent gland
areas on this male kid. The white arrow indicates the location of the second
scent gland that will be burned next.
References
• K Holtgrew-Bohling , Large Animal Clinical
Procedures for Veterinary Technicians, 2nd
Edition, Mosby, 2012, ISBN: 97803223077323