Surgical Conditions of the Ruminant (incl. Castration and Vasectomy) Flashcards
Dehorning – why is disbudding strongly preferred?
- Less stressful.
- Improved LA.
- Fewer complications.
- Reduced risk of horn regrowth.
Dehorning legislation.
Dehorning procedure = act of VS (Veterinary Surgeons Act 1966).
Only vet carry out procedure in cattle >2mths old.
Only vet can dehorn or disbud a sheep or goat – except trimming of insensitive tip of ingrowing horn.
LA must be used (The Protection of Animals (Anaesthetics) Act 1954).
- Which nerve is blocked for disbudding?
- Time for LA to take effect.
- Other recommendation.
- Cornual nerve +/- accessory nerve.
- Minimum 10mins.
- NSAIDs.
- Dehorning instrument types.
- Disbudding instrument.
– Advantages.
- Bains dehorner.
Guillotine.
Embryotomy wire. - Disbudding iron.
– Haemostasis.
– Destroys horn producing tissue.
Dehorning complications.
Inadequate anaesthesia.
Haemorrhage.
Infection: sinusitis.
Fly strike.
Regrowth (common).
- Legislation regarding LA for castration of ruminants.
- Technique of castration in ruminants <7 days old.
- Technique for castration of ruminants at <2mths old.
- Technique for castration of ruminants at >2mths (calves) / >3mths (lambs).
- Not legally required at <7 days old.
Not legally required but recommended at <2mths (calves) / <3mths (lambs).
Legally required at >2mths (calves) / >3mths (lambs). - Elastrator ring.
- Burdizzo / surgical castration.
- Burdizzo / surgical castration.
- Who can castrate ruminants at <7 days old?
- Who can castrate ruminants at <2mths old (calves) / <3mths old (lambs)?
- Who can castrate ruminants at >2mths (calves) / >3mths (lambs)?
- Trained stock person or vet.
- Burdizzo = trained stock person or vet.
Surgical castration = vet only. - Vet only regardless of technique.
Local infiltration of anaesthesia technique for ruminant castration.
LA.
Local infiltration (common).
Vol = 5-10ml dept. on size and site.
In spermatic cord or testes +/- scrotal skin.
Onset of action = 5-10mins.
- LA infiltration into testes method.
- LA infiltration into spermatic cord method.
- Inject 5-10ml of 5% Procaine directly into stroma of testicles using 19G 2-5cm. Painful due to inelastic vaginal tunic.
- Inject 5-10ml of 5% Procaine into each spermatic cord at neck of scrotum using 19G 2-5cm needle. Less painful and faster acting.
- Epidural for castration.
- Sedation for castration.
- GA for castration.
- V rarely used.
Lumbosacral region – L6-S1.
Useful for scrotal surgeries. - E.g. xylazine.
Mature bulls.
Aggressive or difficult to handle animals.
Safe handling. - Recommended for adult boars or pot bellied breeds.
Restraint.
Allow closure of inguinal ring to prevent herniation.
Analgesia for ruminant castration.
NSAIDs.
No legal requirement at present in UK.
- recommended.
- Reduces growth check and less abnormal behaviour seen post procedure.
Castration techniques in the ruminant.
Bloodless.
- Elastrator rings.
- Burdizzo.
Surgical.
- Traction and torsion (twist and pull).
- Emasculators.
- Elastrator ring technique.
- Complications.
- Place ring at neck of scrotum.
Make sure both testicles are included. - Unilateral or failed castration due to retraction.
Failure of the elastrator ring.
Dehiscence and infection.
- Indications for burdizzo over surgical castration.
- Burdizzo technique.
- Poor environmental hygiene.
Farms w/ hx of complications w/ open castration. - Requires dexterity for success.
Apply proximal to testes.
Hold for at least 10 seconds.
2nd application made proximal to first.
Each cord should be crushed separately w/ crush lines staggered to prevent interruption of blood supply to scrotal skin.
Ensure checked 4-6wks later for testicular atrophy.
Burdizzo complications.
Incomplete castration due to failure to occlude vas deferens.
Accidental crushing of urethra (fatal).
Sloughing of scrotal skin.
What factors play a key role in choice of method of haemostasis?
Testicular size, operator experience, age of animal, ruminant spp.
– Cattle <6m = torsion and traction.
– Cattle 6-12m = torsion and traction / emasculators.
– Cattle >12m = emasculators +/- ligation.
– Sheep and goats <2m = torsion and traction / emasculators.
– Sheep and goats >2m = ligation and emasculators.
Considerations for surgical castration.
- Only perform on healthy animals.
- Be aware of environment.
- Be aware of fly season and avoid if necessary.
- Discuss method and risks w/ farmer prior to procedure.
- Analgesia for surgical castration.
- Antibiotic for surgical castration.
- NSAIDs.
- Broad spectrum first generation antibiotic – use with care.
- Surgical preparation of the animal for ruminant castration.
- Initial surgical approach for all methods of ruminant castration.
- Wash scrotum w/ antibacterial solution if dirty.
- Grip scrotum firmly to push testes down.
- Start with testis furthest away.
- Make a bold J incision through the scrotal skin.
- Carefully cut the vaginal tunic.
- Digitally break down ligament attaching vaginal tunic to the testis distally leaving only the vascular attachments.
- Grip scrotum firmly to push testes down.
Continuing surgical approach for torsion and traction castration.
- Twist the testicle ensuring the twists move up the vascular cord.
- Care not to entrap hair or vaginal tunic into the cord.
- Pull firmly on the cord until it breaks.
Continuing w. emasculators method of surgical castration method.
- Apply emsculator to spermatic cord either:
– open vaginal tunic.
– closed vaginal tunic. - Apply “nut to nut” for minimum 2 mins.
- Mature bulls:
– crush the vasculature separately from the vas-deferens.
– +/- proximal ligament.
Completion of all surgical approaches for ruminant castration.
- Scrotum left open.
- Ensure no tissue protruding below scrotal incision.
- Apply topical antibiotic spray.
Surgical castration complications.
- Haemorrhage.
- Infection and abscessation.
- Fly strike
- Tetanus.
- Eventration.
- Adhesions.
Cryptorchidism in the ruminant.
May be a result of incomplete bloodless castration.
Monorchids are rare.
- testicle likely to be retained in the abdomen.
Partial undescended testes more common.
- can be removed as normal but w/ animal sedated or under GA.
- always remove abnormal testicle first.
- if <2m may still descend.
Ram castration.
Rubber ring at birth on commercial farms.
Surgical generally only on pet rams.
V large blood supply compared to calves.
Preferred method of ram castration = closed surgical castration w/ emasculators w/ a proximal ligature.
- Why are animals vasectomised?
- What does vasectomy entail?
- Positioning and restraint for vasectomy.
- Sedation?
- LA for vasectomy.
- To produce teaser males.
- Removal of segment of the ductus deferens.
- Rams held sitting.
- Bulls in lateral recumbency.
- Rams held sitting.
- Recommended.
- Lumbosacral epidural.
- preferred as provides good analgesia and relaxation.
Local infiltration - Line block along neck of scrotum.
Vasectomy method.
- 3cm skin incision made cranial scrotum over spermatic cord.
- Spermatic cord bluntly dissected and exteriorised.
- Place closed artery forceps to isolate spermatic cord.
- Identify ductus deferens.
– medial aspect of the spermatic cord.
– white and glistening. - Clamp and dissect ductus deferens.
- 3-4cm resected and removed.
- Routine skin sutures w/ absorbable skin sutures.
- Repeat for other side.
- What is done w/ sections of ductus deferens after vasectomy?
- Warning for farmer post vasectomy.
- Preserve sections on formalin.
- Label containers well.
- Advisable to get histopathology.
- Preserve sections on formalin.
- Not 100% successful and re-canalisation occasionally occurs.
So allow minimum 2wks to relapse before bull/ram introduced to any fertile females.
Other surgeries of the male ruminant.
Urolithiasis.
- Amputation of the urethral process.
- Urethrostomy.
- Tube cystotomy.
Penile surgeries.
