Front Page ACVC Site Go to First Presentation Go to Previous Presentation Go to Next Presentation Go to Last Presentation
Back to Previous Page Print This Page Save This Page Bookmark This Page Go to the Top of the Page

Avian Clinical Pathology

Don J. Harris, DVM
Avian & Exotic Animal Medical Center
Miami, FL 33156

A growing assortment of laboratory tests is available to the avian veterinarian. Some have been utilized since the inception of bird medicine while others are only now being developed. A few were once considered useful then found to be inappropriate.

As time goes on, the usefulness of available tests is becoming clearer. Of all the implications one thing is certain: nothing is etched in stone. As a popular book once stated, "everything you've read here could be wrong."

The following is a summary of various tests and their significance as experienced by the author. For normal values the reader is referred to one of the many texts listing data for various species. In a clinical setting each result should be weighed against concurrent data and clinical impression. Almost never should one test dictate an entire course of action. Serious errors have been made when not enough information was collected to reveal the true nature of a problem. The key to an effective diagnosis is thoroughness and discrimination.

Laboratory Tests and their Significance


probably the single most useful of all diagnostics interpretations similar to mammals except the Heterophil is the avian counterpart to the Neutrophil; some species respond with a lymphocytosis the way others do with a heterophilia

Alkaline Phosphatase

no specific significance; isoenzymes may be useful


relatively meaningless in birds


see electrophoresis; marked errors in reporting unless measured by electrophoresis


elevated with pancreatitis; some elevation in GI disease


primary source- liver, muscle, kidney; elevation creates suspicion of liver disease

Bile Acids

elevation is a reliable indicator of liver dysfunction; normal values sometimes misleading


inconsistently elevated with liver disease


value linked to protein levels; elevated in preovulatory females, dehydration, some neoplasia; decreased in African Grey parrots with metabolic hypocalcemia syndrome


inconsistent; may be elevated in cases of liver disease, hypothyroidism, starvation


not applicable in birds


elevated with muscle damage or CNS disease


persistently elevated with diabetes, transiently after stress or eating


once thought to be elevated with iron storage disease, now considered unreliable


nonspecific, inconsistent


elevated with acute pancreatitis


inconsistent; elevated in severe renal disease

Protein, Total

must be measured by biuret method to be accurate although temperature compensated refractometer acceptable in non-lipemic samples; decreased with malnutrition, malabsorption, renal disease, liver disease; elevated with dehydration or immune stimulation; many normal total proteins may consist of hypoalbuminemia and hyperglobulinemia, therefore A/G ratio important

Urea Nitrogen

minimally useful; changes inconsistent but related to renal disease or dehydration

Uric Acid

eliminated by kidneys, elevated in renal disease, also elevated in severe dehydration




elevated with renal disease, acidosis, adrenal disease, hemolysis; decreased with diarrhea, alkalosis


elevated in salt-poisoning; decreased with over- hydration


increased with alkalosis and decreased with acidosis



Bacterial C/S

much less significant than once thought- never should be used to gauge the health of an individual; useful if confined to sampling specific sites believed to have pathology

Fungal C/

useful if pathogen isolated; less reliable if negative

Chlamydial C/

most accurate of chlamydial diagnostics if positive; inconclusive if negative

Viral C/

useful if positive; inconclusive if negative

Mycoplasma C/

useful if positive; inconclusive if negative

Chlamydia IFA

most sensitive, least specific; common false positives, rare false negatives

Chlamydia EBA

rare false positives, occasional false negatives

Chlamydia LA

moderate sensitivity/ specificity

Chlamydia CF

moderate sensitivity/ specificity

Chlamydia ELISA

rare false positives, common false negatives; never use as a well-bird screed!!!

Chlamydia DNA

experimental; potential for great accuracy


tremendous accuracy; extremely rare false negatives

Polyoma DNA

extremely rare false positives; common false negatives

Aspergillus IFA

false negatives, false positives




Carrier protein?, osmotic effect


Carrier protein, osmotic effect

Alpha Globulin


Beta Globulin

Immune complexes

Gamma globulin




Heavy Metals

specific screening

Back to Previous Page Print This Page Save This Page Bookmark This Page Go to the Top of the Page
Veterinarian Program
Veterinary Technician/Office Staff Program
Don J. Harris, DVM
Avian Restraint and Physical Exam
You are hereAvian Clinical Pathology
Practical Antibiotic Selection in Avian Patients
Clinical Appearance of Avian Viral Disease
Therapeutic Avian Techniques
Primary Avian Pediatrics
Heidi Hoefer, DVM, Diplomate ABVP
David Holt, BVSc, Dip. ACVS
Debra F. Horwitz, DVM, DACVB
Amy Kapatkin, DVM, DipACVS
Karen Kline, DVM
Kenneth Kwochka, DVM, Diplomate ACVD Dermatology
Gregory A. Lewbart, MS, VMD, DACZM Aquatics/Reptiles
Teresa L. Lightfoot, DVM Diplomate AABVP Avian
Howell P Little, DVM
Sandra Manfra Maretta, DVM
Wendy S. Myers
Karen Overall MA, VMD
Dr. Rodney L. Page & Dr. M. C. McEntee
Paul D. Pion, DVM, DipACVIM
Robert Poppenga, DVM, PhD
Karen Rosenthal, DVM, MS, ABVP
Howard B. Seim, III, DVM, DACVS
Robert G. Sherding, DVM, DACVIM Feline Medicine
Todd R. Tams, DVM
Brian T. Voynick DVM, CVA
Melissa Wallace, DVM, DACVIM Renal Medicine
Cynthia R. Wutchiett, CPA Management