Circovirus spread by dust from faeces, feathers and from parenteral feeding of young.

Feather changes, lesions of the beak/nails (usually symmetrical).

Peracute disease (neonates) caused by septicaemia, pneumonia, enteritis, rapid weight loss and death.

Acute disease (reported at first feather formation) results in depression, +/- feather malformation/loss, +/- crop stasis/diarrhoea/death.

Chronic disease causes feather malformation, retention of feather sheaths, changes of the beak (elongation, fractures, necrosis and ulceration).

Lab findings: haemagglutination (HA) or haemagglutination inhibition (HI) tests can be run to determine immunologic response to PBFD virus.

Prevention: isolate potentially infected birds, virus may be present in all body excretions and secretions as well as shed epithelial cells from GIT mucosa, skin and feathers.

Same family as papillomaviruses. Transmitted through feather dust, excrement and parenteral feeding of young.

Most birds die rapidly (common cause of sudden death in budgie neonates), but carrier states are possible. Also CNS, GIT and respiratory signs.

Depression, anorexia, weight loss, delayed crop emptying, regurgitation, diarrhoea, dehydration, subcut haemorrhage, dyspnoea, polyuria, ataxia, tremors, paralysis.

Cloacal swab for PCR (detects viral DNA) required for diagnosis.

Prevention: environmentally resistant, isolate potentially infected birds, interrupt the breeding cycle with a rest of several months since the disease seems to seems to be self-limiting.

Bacterial enteritis (commonly caused by Gram -ve bacteria/coliforms).

Ruffled feathers, diarrhoea, listlessness, weakness, shivering, vent picking.

Severity of disease depends on age, bacterial virulence, stress and degree of contamination. Neonates often die (less developed immunity).

Salmonella droppings are coloured a sulphur yellowish-green which is very much a diagnostic sign for this microorganism.

Samples: faecal material & blood collected over several days are cultured.

Treatment: fluid therapy, broad-spec antibiotics (sulfa drugs PO + gentamicin/kanamycin by injection), stress free environment + temperature maintenance (e.g. heating using a heat pad).

Gram -ve rod, usually invades secondarily and produces life threatening toxins. Typically outbreaks occur in aviaries when organic matter contaminates water.

Diarrhoea, dehydration, dyspnoea followed by death, skin lesions, localised URT infections (rhinitis, sinusitis, laryngitis).

Treatment: piperacillin, ticarcillin, tobramycin may be used in absence of C+S.

Zoonotic (flu-like symptoms) & notifiable. Transmitted by ingestion (faecal material, feeding of young) or inhalation (respiratory secretions, feather/faecal dust).

Respiratory & GIT signs (oculonasal discharge, dyspnoea, weight loss, depression, lethargy, anorexia, bile-stained droppings and diarrhoea). Signs may be acute or chronic.

Birds may shed bacteria 10 days before clinical signs, and latency/asymptomatic carriers can occur.

Diagnosis: no test 100% effective. Conjunctival and choanal swabs for PCR is gold standard, usually combined with serology. False negatives occur (poor sensitivity) as C. psittaci is a an intracellular pathogen.

Treatment: tetracyclines (doxycycline preferred), some also use azithromycin or enrofloxacin. PO doxycyclin liquid given 35mg/kg SID for 21 days.

Prevention: daily cleaning & disinfection program (use benzalkonium chloride, hydrogen peroxide or 1% formalin). Use litter that won't produce dust (e.g. newspaper) and ensure adequate ventilation/light.

Young, old, unhealthy or those on antibiotics/corticosteroids generally affected (healthy birds resistant).

Emaciation, respiratory distress (tail bobbing), NM disease, abnormal droppings, regurgitation, voice changes, poor appetite, nasal discharge, gout, conjunctivitis.

A. fumigatus, A. flavus, A. niger. Transmitted by spores in environment, often in poorly stored feed.

Diagnosis: tracheal wash for fungal culture, combined with presence of lesions.

Treatment: removal of stress factors, combinations of flucytosine, fluconazole and itraconazole.

Prevention: Reduce contact with nesting materials which may be contaminated with spores, proper feed storage.

C. albicans, a yeast. May affect crop and oral mucosa, intestines, eyes and lungs.

Yeast infection of the outflow of the proventriculus. Affects psittacines and non-psittacines.

General unthriftiness, vomiting/weight loss (esp in neonates), increased appetite. Rhinitis and beak necrosis may occur if the otopharynx is infected.

Lesions are raised white plaques that are easily removed with a cotton swab. Underlying mucosa is thickened and roughened. Crop and oesophagus contains lesions.

Diagnosis: ID of yeast cells on cytology, culture of plaques (abundant growth must be present to be diagnostically significant). Often occurs secondarily to prolonged antibiotics.

Treatment: nystatin most common (added to feed). Can also use ketoconazole, topical iodine or chlorhexidine.

Prevention: removal of all food residue from environment, provide adequate vitamin A, overall cleanliness.

Sick bird look, chronic wasting, neck stretching and vomiting (mucous covered seed), abnormal droppings (variable), polyphagia.

Acute form: die within a few days, chronic form: progressive emaciation and debilitation over weeks/months.

Crop flush for Gram stain & wet mount (Gram +ve rod-shaped filamentous organism).

History: chronic diarrhoea, cloacitis, enteritis, egg laying +/- dystocia, cloacal papilloma

Low humidity (tobacco smoke and central heating dry out feathers)

Neoplasia (birds pick at skin cancers or skin overlying tumours)

Psychological (boredom, overcrowding, environmental changes, poor wing clipping, sexual frustration)

Feather loss in areas accessible by the beak (head feathers remain unaffected).

Tenesmus, staining of vent feathers with faeces/blood, cloacal tissue protruding from vent (with or without an egg attached), do faecal exam (flotation + smear in warmed saline) and Gram stain to detect parasites and bacterial infections.

Differentiate cloacal prolapse from cloacal papilloma by using vinegar on cotton swab and applying to mucosa (papilloma will turn white, prolapse will be unchanged).

Supportive care (fluids), broad-spec ABs, corticosteroids, surgical replacement/resection of prolapsed tissue with purse sting suture placed in vent (don't suture too tight as to close off the cloaca).