Avian and ferret surgery Flashcards
T/F - ferrets are omnivores
False -> obligate carnivores
Weight over season fo ferrets?
Variation over seasons ->
- Hob (male) and Jill(female) will lay down fat stores over winter
- Jills may lose weight in Spring
- Mals may ‘bulk up’ -> gain muscle , lose fat due to testosterone inc in Spring
Can ferrets vomit?
YES -> should be starved
GI transit time ferret?
3-4h
Describe GI of ferret ?
- Simple stomach, very short SI & LI - No caecum
- Don’t starve as long as D & C due to risk of inducing hypoglycaemia (max 4 hrs) -> in geriatric ferrets subclin insulinoma is not uncommon
Ferrets reprod management?
- Unique -> female must be taken out of season
- If surgically neutered -> may predip to adrenal dx
Tip for ferret ventilation?
extend and straighten head and nec, body positioned to minimise abd conents impinging on diaphragm (place a folded cloth under thorax to elevate chest)
What normal TPR values of Ferret ?
T = 37.8-40°C
P=200-400 bpm
R= 22-26 bpm
How an we assess pain (other than grimace scale?
ORBITAL TIGHETNING - high sensitivity and specificity for detection of pain
- +Bhvr changes
- Inc depth & frequency of breaths
- Bruxism and/ or hypersalivation
- change of gait
- Arching back
- Vocalisation when touched
Maintenance fluids for ferret?
60-100ml/kg/d
Where to place IV in ferret?
Cephalic / lateral saphenous vein -> application of topical local anaesthetic
Intraosseous -> proximal femur
Detail intubation of ferrets
Prevent laryngospasm with spray (liek cats)
Tie ET tube over the nose
T/F ferrets maintain some jaw tone even under good anaesthesia ?
True
What are ferrets prone to in anaesthesia ?
Hypothermia - bear hugger, plastic drape etc…
What is a sign of recovery?
Shivering thermogenesis
How to recover ferret?
- Maintain body temp
- Analgesia
- Fluids & nutrition (food as soon as awake)
- Therapeutic laser
- Phovia
What mass excisions do we tend to see?
- Mast cell tumours not uncomon -> benign in ferrets
- Excisional surgery - absorbable monoF suture
What skin surgery do we see in ferret?
- Lump removal -> Neoplastic/ cyst
- Abscess
- wound management
Describe reprod/ breeding in Jills
- Jills reach sexual maturity in first spring after bith at 8-12 months
- Occasionally see signs of oestrust in first AUTUMN if females born early in season
- Seasonal breeders March-September
What is Pro-oestrus inicated by?
Vulva size - lasts 2-3 weeks
When do hobs reach sexual maturity?
9 months
Describe disease prevention in ferret reprod management
- Induced ovulators - will remain in oesturs until mated & chemically brought out of oestrus OR day shortens
- Prolonged oestrus = higher risk of hyperoestrogenism
- Development of pancytopaenia due to bone marrow suppression
What lifestyle aspect of reprod management for owners?
- Reduction in smell in neutered females (may inc risk of adrenal dx).
- Inc testosterone results in inc activity of sebaceous glands
Ferrets - options
- Natural mating (vasectomised / teaser male)
- Delvosteron injection (jill jab) -> NOW NOT AVAILABLE
- Hormonal implant (Deslorelin)
- Surgical neutering (not preferable)
Signs of persistent oestrus? (after stabilizing & inducing ovulaiton)
- Pancytopaenia, subcut & mucosal petechiae, ecchymoses, swolen vulva, pale MMs, abd distention
What uterine dx might make us SPAY ferret?
Pyometra, mucometra, hydrometra
Neoplasia
How do we do OVH in ferret?
● Similar to the ventral midline approach
to the dog.
● Incise approximately 1cm caudal to the
umbilicus.
● Uterus is bicornuate and uterine body
is short
● Ovaries are dark and are situated in a
bursa of fat.
● Ligate vessels with absorbable
monofilament suture material.
● Routine closure
How to castrate ferret?
Open or closed
used monofilament
Vasectomised males - effect on smell?
Retain odour as depends on testosterone levels
How to do Vasectomy ?
- The spermatic cord is palpated cranial to the testis, and a 10 mm skin
incision made directly over it, approximately 20 mm cranial to one scrotal
sac - The vaginal process is identified. * The parietal tunica of the vaginal process is incised and spermatic cord is
exposed - The white vas deferens is identified and a short portion is separated from
the spermatic cord. - Double ligate at a distance of approximately 0.5cm and excise between the
ligatures. - Submission of excised tissue for histological examination is recommended,
to confirm proper excision.
Post op consideraitons of vasectomy in ferret?
- Mild scrotal swelling resolves 2- ays
- Should not be used til 7 weeks post surgery
What alternative approach to vasetomy?
- Palce ligatures around vas deferens
- Clamp on testicle side
- incise the vas above ligature nearest to testicle
- Move cut end down and passed the artery forceps, closer to testicle
- With ligature already placed tie around vas deferens -> create a blind loop in vas deferens
What to do after alternative vasectomy?
Look under mcirosocpe immediately -> motile sperm = vas deferens for sure
- store in formalin - 2 pots Left and Right
Often what are preputial masses?
Often malignat apocrine gland adenoCs
Advanced preputial masses?
May require peniel amputation, resection of the urethra and urethrostomy
What common GIt surgeries on ferrets?
- Enterotomy/ Gastrotomy forign bodies (enterotomy harder bc smaller) -> try to make incision 1cm distal to foreign body to minimise dehisence and stenosis
what other common abdo surgery?
Splenectomy
Details fo spelnectomy?
- Ligate splenic artery and vein supplying the spleen under the visceral side
-> monofilament absorbable suture materal
-> Haemoclips - Caution -> avoid damaging the left lobe of the panreas
Urolithiasis/cystotomy in ferrets?
- Not as common in uk
- Similar to dogs
- Remember -> male has J-shaped penis and an os-penis
Adrenal dx in ferrets?
Loss of neg feedback -> inc in release of LH & FSH. -> persistently stimulate respective receptors in adrenal cortex
Eventually adrenocortical hyperplasia and tumor formation
HOw to Adrenalectomy
- Surgery - left adrenal gland easierto remove -> ligation of the phrenicoabdominal vein
- right adrenal gland more difficult - closely attached to vena cava and in close proximity to the liver
- Tend to avoid surgery in favour of implant
Describe insulinoma in ferrets
- Small tumours of pancreatic beta cells
- Microadenomas -> excess of insulin -> HYPOGLYCAEMIA
- Median age= 5 yrs old
Surgery for insulinomas ?
○ Pancreatic nodulectomy or partial
pancreatectomy.
○ Inspect both right and left pancreatic lobes ○ Survival time of approx. 16 - 22 months (in
combination with medical management)
○ Not all of the diseased tissue may be
macroscopic. Macroscopic disease is usually
seen as discrete red raised nodules
What fractures common in ferrets?
- Radius & ulnea mroe than humerus
- Femur tibia and fibula common
What other orthopaedic complaints in ferrets
- Elbow luxation common
- Ferrets do adapt well if limb amputation required - surgical techniquee is the same as in dog & cat
Why do we do tail amp in ferret?
- Chordomas (MSK neoplasm)
-> slow growing and benign
How to do Tail amp in ferrets
- AMputate tail 2-3 coccygeal vertebral bodies proximal to the lesion
- Ensure haemostasis of the ventral artery & vein
-Close skin with single interrupted monoF absorbable Sutures
Assess hydration of BIRDS for anaesthesia …
○ Methods are subjective +/- in combination with lab tests
○ Skin turgor – variable → less elasticity in birds compared with mammals.
Assess over pectoral muscles in birds.
○ Venous refill time - >2 seconds at 7-9% and >3 seconds at 10-15%
What temp in birds is normal?
41-44°C
What to beware of with ET placement in Birds
Care not to damage delicate tracheal tissues as this can lead to strictures/ stenossi. Complete rings of cartilage and lack of epiglottis
What often required with birds?
IPPV (intermittent positive pressure ventilation)
Should u withhold food / how long if so? (bird)
● Ideally withhold food to ensure empty crop (if present). Species
variation!
○ Budgie – 1 hour
○ Most larger parrots – 3 hours
What is the average daily fluid maintenance in birds
100ml/kg/day
What IV lines inbirds?
- Basilic (ulnar/brachial vein)
- Extend wing and visualise vein
- Vein runs over the elbow area
- Care as haematoma formation is common
- Medial metatarsal vein
(Vein is very short in psittacines but possible site
for chickens, waterfowl, waders & seabirds during
a procedure → meticulous skin prep required.)
How to Crop tube?
into crop or at level of thoracic inlet for species without a crap (owls)
general rule = crop volume is calculated as 5% BW -> LOWER in debilitated patients
What SC injection routes for fluid therapy
→ inguinal or precrural folds,
wing web (propatagium), axilla, interscapular area
Describe SC injection
o Up to 20ml/kg → I would tend to go LOWER
if no other option but to use this route.
o Can add hyaluronidase – 1500IU/L added to
sterile crystalloid fluids – increases
absorption
Describe Wing Clipping
- Temporary method of deflighting -> never perform during a moult or if blood feathers present; never do unilaterally
What could go wrong in <ing clip?
● Falls, fractures, injuries to keel
● Self traumatising
● Inability to escape and caught by owners
other pets
● In some cases still being able to escape →
owner’s false sense of security.
What pattern options for a wing clip?
- Clipping in a curved pattern
- Clip outer primary feathers
- Leave the outer 2-3 primary feathers an clip the next 5-8
Describe Nail Buring in birds?
-> address potential causes : check perching, pododermatitis?
Arthritis?
Diet
Should we beak trim?
- Common request but not routine bc normal beaks DONT need this
Reshapinig of beak required if…?
- Congenital abnormalities
- Trauma and damage
- Abnormal keratin metabolism
How to beak trim?
- Always burr not lip! clipping inc chances fo iatrogenic damage
- Where poss -> GA
Blood feathers can cause a lot of blood loss - T/F
True -> cornflour to stem bleeding, bring into surgery, may rq fluids
Should we pull out feather (blood feather)?
May damage follicle
Current thought is to ligate
What to do for constricted leg ring or jesses?
->under GA
- Radiograph before and after
- Fremel with cutting burr or dental drill piece
- Protect underlying tissues
- Surgical debride necrotic tissue
- Remember to microchip!
- Phovia
Which lumps do we see in birds?
Not uncommon to see cutaneous and subcut neoplasms
- Lipomas often see in psittacines -> total surgical removal often curative
- Xanthomas
- Feather cysts
What are Xanthomas ?
(intradermal deposits of cholesterol clefts with an associated inflammatory reaction) -> highly vascularised -> surgical removal when small is advised
Describe feather cysts ?
● Feather cysts → unerupted feathers → inflammatory swellings.
○ GA, surgically open the cyst, clean, allow to heal by second-intention
○ Reoccurring cyst → surgically remove, together with the dermal papilla from
which it develops. Approach from dorsal aspect.
○ Care – feather follicles have a rich blood supply
What is preen gland also called?
Uropygial gland
What can cause swelling or the uropygial gland?
- ductal blockage
- Gland abscessation
- Neoplasia
Describe Neoplasia of the preen gland?
○ Significant blood supply
○ Radiosurgery advised
○ Gland is bordered ventrally by fibrinous connective tissue that attaches firmly
to the dorsal surface of the pygostyle and caudal vertebrae
○ Surgical removal must extend to the connective tissue layer.
○ In many species the gland is separated by a septum → possible to perform
unilateral gland removal
What is a common issue with wound management in birds?
Dessication and devitalisation fo subcut tissues -> decision wether to let heal by first or second intention
What commonest site for skin deficit in birds?
Cranium
How to stich up a bird?
Closure by horiontal matress usig monoF absorbable suture material
What leads up to a rinolith removal?
- Chronic rhinits, oten concurrent sinusitis -> formation of a hard,plus of debris blocking th enares
- Often caused by hypovit A
What can rhinoliths cause?
Can cause progressive destruction to soft
tissues of nasal passages, the rostral nasal
conchae +/
- sinuses.
How to remove rhinoliths?
- Small nasal plugs -> remove with blunted dental pick/ probe
- Larger rhinoliths -> surgical debridement udner GA
Describe Respiratory Anatomy/ Physiology of birds
● No diaphragm
● Semi-rigid lungs
● Air sac system
○ Clavicular air sac
○ Paired cervical air sacs
○ Paired cranial air sacs
○ Paired caudal thoracic air sacs
○ Paired abdominal air sacs
● Respiratory system 10 x more efficient
Why do we do air sac cannulation?
- TO bypass URT -> used for oxygenation, ventilation and anaesthesia
When should u not place AIr Sac Tube?
Ascites
Where do we put air sac cannula
Caudal thoracic or abdominal air sac on the left hand side
Describe how to doan air sac cannulation?
● Place the bird in right lateral recumbency → remove feathers and prepare the
paralumbar fossa behind the last rib.
● Incise the skin with a scalpel blade & using mosquito forceps, held close to the tip
for more control, advance in a craniodorsal direction until a pop is felt.
● Widen the insertion site by opening the forceps and then place the tube
● Suture the tube to the body wall.
● Tubes should not be left in place for longer than 4-5 days
Describe how to judge the internal diameter / placement of the tube?
○ The internal diameter of the tube should ideally be 1.5 times wider than the
size of an endotracheal tube placed in the glottis
○ Make sure the tube is not too deep as it will contact internal viscera and
obstruct and/or cause damage.
○ Test the patency by placing a feather in front of it and seeing it move with
respirations.
What GIT surgeries (crop) of the bird do we tend to do?
- Crop injuries -> ruptured crop
- Burns -> often present with necrotic grnaulating wound forming a crop fistula
- Ingluviotomy (remove foreign body)
Who commonly gets ruptured crops?
Baby psittacine birds being human reared -> burns of FB
What to do for a crop fistula due to a burn?
○ Stabilise for 2-3 days
○ Broad spectrum antibiotics, analgesia and proventricular gavage (can go via the crop wound)
○ Await demarcation
○ GA, surgically separate crop wall from the skin.
○ Close crop using a double inversion pattern.
○ Skin closure
Describe how to do an ingluviotomy ?
○ Place bird in dorsal or lateral recumbency and elevate the head
○ Place a probe/feeding tube into the mouth and into the crop to delineate the position of the
crop.
○ Incise the skin close to the thoracic inlet and over the left lateral crop wall.
○ Visualise and isolate the crop wall.
○ Place stay sutures & incise into an avascular area of the crop wall. Only make an incision
one-third to one-half the length of the skin incision
○ Remove foreign body
○ Close with monofilament absorbable suture using a single or double continuous inversion
pattern. Close the skin.
WHAT RELEVANT REPDO TRACT CONSIDERATIONS IN BIRDS?
● All birds have a cloaca
○ Coprodeum
○ Urodeum → contains openings of
the ureters and the genital ducts.
○ Proctodeum
● Reproductive tract of female
psittacines located on the left hand side
of the coelom.
● Right ovary and oviduct normally
regress prior to hatching (psittacines)
● May have vestigial remnants or even
functional after hatching (raptors)
Who commonly gets Dystocia?
Small psittacines -> Commonly seen in cockateils -> can produce repeated clutches or a larger than normal clutch
Why can we get dystocia in birds?
Depletionof Ca and protein stores -> poor bone density, weight loss, pathological fractures & dystocia
Describe Dystocia Surgery steps
○ Incision site depends on position of egg. Laparotomy approach is either
caudal left lateral or usually (if egg is in the distal oviduct) a ventral
midline approach, between the pubis and sternum.
○ Care when incising the musculature.
○ Incise oviduct directly over the egg.
○ Salpingohysterectomy may be required at a later date once more stable
○ Close oviduct with monofilament absorbable material with a single
interrupted or continuous inversion suture pattern.
When is salpingohysterectomy indicated?
severe egg peritonitis, dystocia with egg remnants in oviduct
- The ovary is firmly attached to the dorsal abdominal wall so NOT removed
- All the oviduct and uterus must be removed instead
Describe Bird MALE reprod anatomy?
- Males -> two testes located ventral to the cranial border of the kidney
- Most Companion birds do not have a protruding phallus -> exception= waterfowl
- Phallus of waterfowel purely for reprod function
- If traumatised can surgically amputate
How is the avian thoracic limb adapted for flight?
- Thoracic girdle, scapulae, coracoid bones & clavicles
- Large superficial pectoral muscles > down stroke of wing - thrust during flight
Traumatic ortho injuries common in which birds?
Wild birds > 100g & free flyign pet birds
Prognosis for orhto (wing) injuries?
- Can be good with cage rest (3 weeks)- + pain releif if simple fracture
- Pg poor for (sub)luxations and injuries involving shoulder joint
What bones present in the wing?
Short humerus, paired radius & ulna, carpal bones and carpometacarpus
What are the three digits of bir?
alula (the pollex is the
joint which bears the alula, major digit & minor digit.
Describe first aid stabilisation of fracture ?
elbow or more distally =
figure of eight bandage; humerus or shoulder = wing to body
bandage
What bone considerations ?
smaller sized patient, bones are quite brittle
with a thin cortex and large medullary cavity compared with
mammals.
Recap bone sof pelvic limb - bird?
Femur, tibiotarsus and fibula, tarsometatarsus, four digits
What first aid stabilisation on bird LEG ?
leg
fracture (distal to stifle only): Altman
splint (birds < 200g), improvised
splint/cast for larger spp. Toe Fracture:
Shoe/Ball bandage
Who is pododermatitis (bumblefoot) commonly seen in?
Raptors, psittacines, chickens, ducks and mute swans
What can birds get on plantar aspect of the foot ?
Non infectious soft tissues granuloma
cause of pododermatitis?
– walking on hard surfaces → small wounds → secondary infection (S. aureus). Also seen if uneven weight
bearing, ? Injury. Hypovitaminosis A.
Secondary systemic amyloidosis is potentially ….?
Fatal
TX for raptors, psittacines, and chickens
○ Evaluate the integument, surgically prep the foot, remove the scab and take samples for C+S
○ Depending on severity remove exudative material or carefully incise around the lesion taking care of vital structures
○ Suture (with no tension on suture line) using simple interrupted pattern
○ Bandage feet/Bumblefoot shoes → regular bandage changes
○ Remove sutures in stages after 21 days.
