Avian dermatology Flashcards
Describe the avian integument as a general concept of health?
- The condition of the skin and feathers of the bird provides the avian clinician with a clinical window into the general health, nutritional status, management and environmental conditions to which the patient is exposed
- Familiarity with the avian integument and the ability to distinguish between normal and abnormal is a essential tool in diagnosing nutritional and organ based disease as well as those specifically of the avian integument
What is seen here and what has caused it?
Periorbital ‘Abscess’
- Accumulation of cellular material within the sinuses
- Cause:
- Respiratory infection and associated Vitamin A deficiency (General malnutrition)
- Diagnosis:
- Site specific. Very typical.
- Treatment:
- correct the nutrition and surgical debridement
- Common Species:
- African Grey. Chicken (Mycoplasma induced)
Discuss avian lipomas?
Lipoma
- Organised fatty swelling (Benign neoplasm of lipocytes)
- Appearance:
- Smooth raised masses growing in the subcutis; yellow in appearance. (Do not confuse with subcuticular fat deposits which occur in same areas but are not organised)
- Cause:
- Obesity (malnutrition); Breed disposition
- Distribution:
- Mainly sternum abdomen (Amazons, Budgies, Cockatiels)
- Pericloacal region (Galahs)
- Treatment:
- Consider removal or advise leave
- Correct nutrition (+/- responsive but always necessary)
Photo shows post surgical photo of a racing pigeon following removal of a mesenteric lipoma
Discuss avian Xanthomas (‘Yellow mass’)?
- Not neoplasms - although benign can become a clinical problem if they become large or the bird self traumatises causing bleeding
- Appearance:
- Yellow, thickened, featherless areas of skin often vascular and friable
- Cause:
- Dermal infiltrations of cholesterol filled macrophages due to diet? trauma? Breed/colour (Yellow)
- Distribution:
- Anywhere but mainly dorsum and wings
- Treatment:
- Excision (problematic); Amputation of wing
- Species:
- Budgies; small psittacine birds
Discuss feather cysts?
Feather Cysts
Appearance:
Lumpy irregular masses of keratinous debris (necrotic feathers). Sometimes closed resembling abscesses more often open exuding caseous material and ‘bits’ of feather
Cause:
Genetic and hereditary – breed and feather-type predisposition in canaries. Norwich, ‘double buffing’
Distribution:
Dorsum and wings. Can be singular or extensive. Progressive increase in number with each moult/age
Treatment:
Excision (often unrewarding as other cysts form).
Euthanasia if extensive and bleeding due to self-trauma
Identify lesions on the picture?
What other lumps and swellings can be found on birds?
- Squamous cell carcinoma
- Cutaneous papillomas
- Melanomas
- Fibromas
- Uropygial Gland
- Adenoma
- Adenocarcenoma
- Abscess/Impaction
- Subcutaneous emphysaema:
- Leakage due to ruptured airsac; # bone.
- Normally resolves
Outline some reasons for feather loss without plucking?
- Normal moult/escape moult
- Abnormal moult (Malnutrition)
- Apteria (Non-feathered areas)
- Hormonal disorders?
- Genetic (Baldness in lutino cockatiels)
- Mate mutilation (Normally on top of head)
- Papova and Polyoma virus (‘French Moult’ Budgies)
- Cutaneous Pox virus
Discuss Psittacine Beak and Feather Disease (PBFD) which causes feather loss?
Psittacine Beak and Feather Disease (PBFD)
Circovirus
- Affects the growing feather follicles; which results in:
Dystrophic feather growth. Feathers appear pinched-off
Progressively gets worse with successive moults
Abnormal feather colouration (red streaks)
+/- Necrotic beak lesions
Can affect liver as well
Diagnosis:
(Always suspect PBFD and rule out)
- Clinical appreciation of feather dystrophy
- Lack of powder down feathers (shiny beak)
- PCR test (+ve =+ve; -ve = test again?)
- High incidence in white cockatoos and Af Greys
Knemidocoptic Mites (Scaly face; Scaly leg) can cause feather loss without plucking. Discuss further?
- Knemidocoptic Mites (Scaly face; Scaly leg) Classically infects the non-feathered areas of the face (cere and beak) and legs of budgiesResults in ‘honeycomb’ appearance of tissue or hypertrophy of the scales of the leg
- May result in leg bands becoming too tight
- Causes excessive growth of beak
- Nutritional and immune status of individuals
- Can be confirmed by scraping and microscopy
Treatment:
- 2-3 drops Ivomectin direct to site. 3x weekly applications. Soften heavy scaling (poultry) with liquid paraffin for a few days prior to application
- DDx – Benign hypertrophy of cere – old age
What is a cere?
Discuss bacterial and fungal folliculitis?
- Bacterial and fungal folliculitis
- Often resulting in necrotic, malformed, easily damaged blood feathers, especially of the tail (May also be nutritional)
Diagnosis:
- Feather pulp cytology and culture
Treatment:
- Nutritional modification
- Appropriate oral antimicrobials
- Wash/spray affected area with antimicrobials (F10)
How are damaged blood feathers treated?
Treatment:
- Over the phone suggest (assess the owner and the bird):
- Pulling out the bleeding feather (Site dependant)
- Pinching it with fingers/forceps to assist clotting
- Dusting it with cornflower (merits??)
In surgery
- Pull out feather +/- GA (assess force required/site)
- Administer pain relief: oral (maloxicam injection /drops); local pain relief (Healx Soother Spray);
- Correct/discuss the underlying cause
Typical feather picking sites include the propatagium (inner elbow), inner thighs and sternum
Causes can be divided into the 3 P’s:
Pathological (medical)
Psychological (behavioural)
Physiological (hormonal)
What is the model for feather plucking?
Despite owners preconceptions parasites are an uncommon cause of feather loss, although they may cause irritation, agitation and poor feathering
Always consider the underlying conditions that exist that predispose to external parasites
What parasite can effect birds?
- Knemidocoptes mutans and pilae
- Lice – sucking and chewing
- Canaries, Pigeons, Swans, Poultry
- Ticks – serious cause of individual death
- Aviary birds
- Birds of Prey
- Red mite – Dermanyssus gallinae
- Very serious problem in bird rooms. Disrupt incubating hens and kill chicks due to anaemia. Difficult to control. Said not to affect Zebra Finches
Discuss leg and toe problems?
Problems with Rings
Too tight due to:
- Wrong size
- Ring trauma – self, other bird, cage/toy trauma
- Increase in size of leg
- Leg trauma
- Hyperkeratosis
- Scaly leg
- Tassel leg – old age
- Foreign body wedged in gap causing swelling
What can be seen here?
Articular gout
- More a metabolic problem but crystals readily visible around the tarsal joint as discrete, hard, raised, white/yellow lesions 1-3mm in diameter
- Do not confuse with abscesses
- Very haemorrhagic if incised
- Confirm diagnosis by staining for uric acid
- Treatment ??????? – probably not effective at this stage
- Ensure husbandry and perching appropriate
- Possible pain relief
- Euthanasia??
- (Allopurinol)
Discuss pododermatitis (bumble foot) and its causes?
Primarily a disease of captivity
Most commonly seen in Raptors with a higher incidence in falcons than hawks (Also in Psittacine birds and Waterfowl)
Characterised by inflammation and often abscessation of the sole of the foot and planter aspect of the digits
Caused by a combination of:
- Nutrition
- Obesity
- Inapprpriate perches (Concrete edges to side of ponds -ducks)
- Lack of exercise
- Poor blood circulation to the foot
- Cardiovascular changes at the end of the hunting season
What is the treatment for bumblefoot?
Treatment (Depending on severity):
- Consider euthanasia (Type 4+) on humane grounds
- Surgical removal of necrotic tissue (Type 3)
- Suture to attempt closure by first intention
- May require hydrocolloid dressing
- Culture of necrotic debris for accurate antimicrobial therapy
- Use of foam ‘snow-shoe’ and conforming bandage (T 3-2)
- Correction of predisposing causes (Types 3-1)
Prevention:
- Address husbandry issues
- Routine application of foot creams
What can cauterise a bleeding toe?
Sliver nitrate pen
AgNO3
