Avian Medicine Flashcards
Identifying sick/deteriorating animals
- Birds hide symptoms - illness makes them a target to
- A bird that looks sick is v sick! - crisis state
- Rapid metabolic rate -> rapid change in condition
- Minor changes - monitor weight, demeanour, activity
- Proactive w/ management
Signs of ill health
- Fluffed up
- Loss of appetite, weight or condition
- Alteration in faeces
- Loss or change of voice/vocalisation
- Changed behaviour, less active
- Sleeping more
- Standing on 2 legs/abnormal stance
- Reduced performance
- Change in height of perching/on floor
- Change of balance (tail up or down)
- Tail bobbing
- Abnormal bodily discharges
- V+/regurg
- Wings hanging down
- Hanging onto perch/cage with beak
Standard starting Dx protocol
- Haematology - nucleated RBCs, cannot run through machine, will have to do blood smear
- Biochem
- Lateral + ventrodorsal radiographs
Blood sampling
- Jugular - apterium (featherless area) on RHS of neck - align vessel w/ vertebrae before sampling to allow application of pressure for haemostasis
- Superficial ulnar vein - catheterisation, blood sampling from catheter, haematoma formation greater
Radiography - R lateral
- Extend wings dorsally + legs caudally
Radiography - ventrodorsal
- Extend wings laterally + legs caudally
Common conditions
- Sour crop
- Fractures
- Squirrel bites
- Bumblefoot
- Wing tip oedema
- Aspergillosis
Wing tip oedema
- Typically affects raptors from warm climates - Harris hawks, Lanner falcons, frst year birds predisposed
- Occurs in winter when temperatures drop
- Blood supply to the wing tip is compromised -> oedema of the metacarpi develops, dry gangrene follows with loss of the wing tip
- Loss of primary feathers leads to permanent flight
compromise - CS - dropped/abducted wings, swollen metacarpi, loss of one or both wing tips
Wing tip oedema - Tx
- Gentle warming
- Physiotherapy (manual/flight if possible)
- Sterile draining of any vesicles
- Isoxsuprine (Navilox)/Propentofylline (Vivitonin)
- Topical Preparation H
- Covering AB therapy
- Tx hopeless if wing tip already lost
Aspergillosis
- Commonest respiratory disease of captive bird
- Multiple species capable of disease: A. flavus, A. niger, A. fumigatus (most common), A terreus
- Non-contagious but can appear to cause outbreaks with group exposure to spores
- Opportunistic infection - Immunosuppression: concurrent disease/stress/malnutrition
- Marked predisposition in Goshawk, Golden Eagle, Gyr
falcon and Snowy owls - Overwhelming challenge: housing close to compost/hay/wood
- Aflatoxins cause hepatic pathology
- Marked leucocytosis
Syringeal aspergilloma
- Fungal granulomas form on the syringeal mucosal folds at base of trachea
- Progressive air flow obstruction develops
- Early signs - changes in vocalisation
- Acute dyspnoea occurs as granulomas grow
- Dx - tracheoscopy
Syringeal aspergilloma - Tx
- Stabilisation: air sac tube, supportive care
- Debridement (surgical/endoscopic
- Systemic antifungal therapy - Itraconazole - not as effective (toxic in AGPs), Voriconazole, Amphotericin B
- Nebulisation
- Dietary and environmental improvement
Air sac aspergilloma
- Caudal air sacs generally affected - natural deposition of spores as air flow slows
- CS - no respiratory signs, general malaise, hepatic dysfunc, green droppings - inc bile pigment
- Tx - Surgical/endoscopic
debridement; anti-fungal therapy; nebulisation - Less favourable Px
Lung aspergilloma
- Severe necrotising fungal pneumonia
- Dyspnoea - acute onset -> rapid death
- Poor Px
Crop tube feeding
- Vital procedure
- Support bird in a towel
- Restrain head/jaw
- Pass tube into side of mouth on birds left
- Over the tongue and down the birds right side - avoiding the glottis
- Palpate the tube tip in the crop before feeding
Common conditions (parrot)
- Beak overgrowth
- Wing clipping
- Resp compromise
- Feather plucking
Beak overgrowth
- Should be worn effectively w/ appropriate management conditions
- Inappropriate wear - wrong diet; lack of chewing material (naturally destructive and will readily chew branches, toys, furniture)
- Infectious pathology - Knemidokoptes mite infestation; Circovirus (Psittacine Beak and Feather Disease) - Cockatoos appear most likely to develop severe
beak and nail changes - Previous trauma - malocclusion results + even wear is compromised; hand-feeding of juveniles is a common cause
- Abnormal growth - liver pathology, can be 2y secondary to malnutrition, hormonal irregularities - inc ovarian hormones, chlamydophila etc.
- Neoplasia rarely reported
Beak overgrowth Tx (parrot)
- Rotating abrasive tool or burr is used
- Comprehensive trimming requires anaesthesia
- Minimises stress, beak can be reshaped properly + intraoral beak surfaces can be accessed
- ET tube can be placed to prevent dust inhalation
Resp compromise
- Dyspnoeic bird = severely ill bird
- Stabilise in oxygen chamber while taking history
- Investigation under anaesthesia may need to be
attempted even in an unstable case - Warn owners that prognosis is guarded
- Investigation crucial as many causes can present as respiratory compromise and all have different approaches needed
Resp compromise - causes
- Respiratory disease
- Cardiovascular
- Toxic
- Coelomic compression
Resp compromise - resp disease causes (parrot)
- Aspergillosis
- Chlamydophila psittaci (Psittacosis/ornithosis)
- Inhaled foreign body (usually cockatiels)
- Tracheal stricture
- Tracheal trauma
- Pneumonia
-Tracheal parasitism (Syngamus spp.) - gapeworms
Resp compromise - CVS causes
- Congestive HF - common in older owls, associated w. atherosclerosis in psittacines, positive correlation w/ chlamydia
- Anaemia - acute H+/chronic disease, IMHA reported in raptors
Resp compromise - toxic causes
- Teflon inhalation = emergency e.g. non-stick pan overheated -> rapid pul oedema + H+, due to birds having v rapid resp system
- Resp irritants - smoke, aerosols
Resp compromise, coelomic comopression causes
- No diaphragm present
- Coelomitis (often repro tract origin)
- Ascites
- Hepatomegaly
- Neoplasia
Feather plucking - internal discomfort
- Air sacculitis (always check for Chlamydophila)
- Renal pathology
- Metabolic bone disease
- Chronic enteritis (beware proventricular dilation syndrome = viral cause, test for bornavirus)
- Osteoarthritis
- Angina
Feather plucking - dermatological factors
- Preen gland impaction/infection - 2y to malnutrition (lack of Vitamin A) -> dry, brittle feathers
- Quill mites in kakarikis
- Polyfolliculitis in love birds
- Abnormal feathers - beware PBFD (Psittacine Beak and Feather Disease) if distorted/abnormal coloured feathers, altered smell or texture e.g. smoke, triggers removal
Feather plucking - behavioural + physiological factors
- Displaced aggression/frustration
- Stressors in environment
- Alteration or lack of a routine
- Sexual/breeder frustration in imprinted birds
- Lack of stimulation and ‘boredom’ associated
- Physiological - mate preening in Macaws -
- Inc w/ stressed to release more endorphins to deal w/ stressors
Feather plucking - Dx + Tx process
- Comprehensive medical investigation necessary to
identify health factors: Haematology and biochemistry, Radiography, Chlamydophila serology, Other tests as indicated - Diet and management invariably need improvement even if not yet causing problems
Egg peritonitis (pet poultry)
- Inflammation of
a bird’s reproductive tract and coelomic cavity - Most common reason for presentation of chickens
- Ectopic follicle/yolk causing severe coelomic ‘foreign
body’ reaction
Egg peritonitis - aetiopathogenesis I (pet poultry)
- Failure of a follicle to move into the infundibulum -> yolk instead is ovulated into the coelom
- Single episode causes mild inflammation
- Usually self-limiting
- Adhesions can lead to secondary problems
Egg peritonitis - aetiopathogenesis II (pet poultry)
- Follicle ovulates normally but external trauma leads to
oviduct rupture and leakage - Scarring and inflammation of oviduct likely to predispose to ongoing problems
- Difficult to identify as trauma usually unseen and little external indication