Chlamydiosis and Fungal disease of Birds Flashcards
Avian Chlamydiosis
Chlamydia psittaci
Small, obligate intracellular bacterial
Obligate = depends on host cell for energy needs
Avian Chlamydiosis
Transmission
Fecal-oral, aerosol, secretions
Persists in organic material - aersolization from dried feces common
Avian Chlamydiosis
Susceptibility
All birds
Most commonly affected pet birds: budgerigars, cockatiels
Avian Chlamydiosis
Other names
psittacosis, ornithosis, parrot fever, chlamydophilia
Avian Chlamydiosis
Biphasic Development
Elementary bodies
Infections
Extracellular
Metabolically nonacitve - no reporduciton, not susceptible to antibodics
Shed by infected animals, then ingested or inhaled by host
Attach to cell and penetrate → Reticulate Body
Avian Chlamydiosis
Biphasic Development
Reticulate Bodies
Intracellular
Metabolically active form
Reproduces by binary fission and are susceptible to antibodies
Outcome: condense inot elementary bodies and passes to daughter cells during mitosis, released from cell if cell lyses or ithere is endosome fusion
Once released, revert back to elementary bodies
Avian Chlamydiosis
BIphasic development
Intermediate Body
Form between RB nd EB
AKA dispersing form, condensing form
Not reproductively active
Form in sub-optimal conditions
Avian Chlamydiosis
LIfe Cycle
Can be as short as 48 hours
Avian Chlamydiosis
Incubation period
5-19 days
Avian Chlamydiosis
Clinical Signs
No pathognomonic signs → easily confused with other dieases
Vary widely
Asymptomatic - many birds are carriers
Symptomatic - lethargy, weight loss, anorexia, diarrhea, oculonasal discharge, sinusitis, Systemic compromise to liver = change in urate color, Uncommon: head tilt, paresis, tremors
Avian Chlamydiosis
Antemortem Diagnosis
CBC
Sometimes anemia, leukocytosis, heterophilia, monocytosis, toxicity
May see inclusion bodies in heterophis
Avian Chlamydiosis
Antemortem Diagonsis
Biochemistry
elevated liver enzymes, uric acid, beta globulins, bile acids
Avian Chlamydiosis
Antemortem Diagnosis
Radiographs
Hepatomegaly, splenomegaly, air sac thickening
Avian Chlamydiosis
Antemortem Diagnosis
DNA PCR
Live organisms are not needed
Contaminants can inhibit PCR and give false negative
Cross contamintiaon at any step can give false postitve
CCC swab
Avian Chlamydiosis
Postmortem Diagnosis
Hepatomegaly, splenomegaly, air sacculitis, pericarditis, pneuomonia, enteritis, nephrosis
Intracytoplasmic inclusions
Fibrinupurulent Serositis
Avian Chlamydiosis
Treatment
Tetracyclines - best
45 day course, oral and IM forms
Azithromycin
Retest 2-8 weeks after treatment
Avian Chlamydiosis
Mangement and Prevention
Quarantine - 30 days and tesl all new introduciton into a collection
Immunity short lived
Clean and disinfect shortly after treatment initiation and treatment conclusions
Avian Chlamydiosis
Zoonotic risk?
VERY ZOONOTIC
Inhalation or ingestion of contaminated dust - usually exposure to urban pigeons
Human Sings: wide range
Flu-like symptoms to death
Aspergillosis
Saprophytic fungus
Ubiquitous in environment
Opportunistic pathogen
NOT contagious
Aspergillosis
Species Susceptibility
Arctic and Northern raptor
some juvenile birds
Penguins
Some parrots: african grey
Pelagic birds
Aspergillosis
Risk Factors
Various substraes: hay, straw, corn
Immune status: neoplasia, circovirus, coritcosteroid treatment
Poor ventilation
High heat and humidity
Form of Aspergillosis
Apergillosis
Clinical signs
Most commonly, respiratoty signs
Chronic weight loss and anorexia
Decreased fitness
Aspergillosis
Diagnosis
CBC - marked leukocytosis
Imaging - opacities in the lungs and or air sacs
Coelioscopy - GOLD STANDARD, biopsies for cytology, histopathology, culture
Aspergillosis
Dioagnosis - Limitied Utility
Antibody Detection
Humoral immunity less important than cellular for fungal infections
May be present in healthy patients
Negative - does not rule out infection
Postive - oly useful in conjunction with other findings
Aspergillosis
Dioagnosis - Limitied Utility
Galactomannan
Detects fungal antigen galactomonnan
False positive common d/t cross reaction with other antigens
Fasle negative - common not understood why
Aspergillosis
Treatment
Itraconazole, vericonazole
Allyamine: terbinafine
Polyenes: amphotericin B
Best success with a combination of drugs and routes of administration
Candidiasis
Candida albicans
Ubiquitous yeast
Candidiasis
Susceptible
Unweaned chicks
Juvenile parrots
Cockatiels
Immunocompromised birds
Birds on long term antimicrobials
Candidiasis
Cause of Infections
Endogenous due to yeast overgrowth
Oral inoculation of overwhelming numbers
Candidiasis
Physical Exam Findings
Isolated to the GIT
Oral whit lesions
White lesions along GIT
Candidiasis
PE Findings
Adult bird
Weight loss
Lethargy
Dull plumage
Candidiasis
PE FInding
Young Birds
More severe
anorexia
crop stasis
white plaques in oral cavity
Regurgitaiton
Weight loss
Candidiasis
Diagnosis
Cytlogy of the mouth, crop swan, or fecal swab
Considered normal when in low numbers and when not budding
Candidiasis
Treatment
Nystatin
No systemic absorption
Requires direct contact; with lesions
consider for milder form of disease
Large volume required
Fungistatic and not absorned form GIT → only effective in direct contact with tissue
Low toxicity
Candidiasis
Treatment
Fluconazole
Systemic absorption
Consider for more sever forms of disease, when systemic concerns arise
Macrorhabdosis
Macrorhabdus ornithogaster
Previously called Megabacteria ornithogaster or Avian gastric yeast
Obligate pathogen yeast, typically of smaller bird species
Macrorhabdosis
Susceptible
Budgerigars
Lovebirds
Parroltlets
Eclectus parrots
Passerines
Ostriches
Macrorhabdosis
Clinical signs
Often nonspecific
Weight loss - “going light syndrome”
Progressive over months, usually with good appetite
Regurgitation
Diarrhea and maldigestion
Melena
Macrorhabdosis
Differential diagonsis
Trichomoniasis
Candidiasis
Heavy metal toxicity
Bacterial ventriculitis / entertitis
Neoplasia
Avian Bornavirus
Macrorhandosis
Antemortem Diagonsis
Challenging - shedding intermittent
CBC/Chemistry - nonspecific, anemal, decreased electrolytes
Imaging - nonspecific, proventricular dilation
