Common Avian Diagnostics Flashcards
How are RBCs and WBCs assessed?
RBC - PCV, total RBC (manual), morphology
WBC - total WBC, differential, morphology
What WBC do avian species lack compared to reptiles?
azurophils
What is abnormal to find within avian RBCs?
mitotic figues
What are 2 unique functions of thrombocytes? What do they look like?
- hemostasis
- phagocytosis of bacteria
small, oval, basophilic nucleus with clear cytoplasm (arrowhead)
What cells are seen in this smear?
different stages of RBC maturation
- a = immature, round, chromatin, basophilic nucleus
- b = polychromatophilic, elliptical, basophilic nucleus
- c = mature, elliptical, orange cytoplasm, basophilic nucleus
What is occurring in this blood smear? What can cause this?
cytoplasmic ballooning
lead poisoning (may also see basophilic stippling)
What is occurring in this blood smear? What can cause this?
hypochromic RBC with abnormal nuclei
zinc/lead poisoning
What is occurring in this blood smear? What can cause this?
Heinz body formation
petroleum toxicosis
What is considered anemic in birds? What indicates regeneration? What are 3 causes?
PCV < 35%
increased polychromasia and presence of reticulocytes/immature RBCs (usually <5% are polychromatic)
- loss - trauma, hemoparasites
- destruction - sepsis, hemoparasites
- decreased production - drug reaction, decreased EPO
What are the 2 types of polycythemia?
- primary - myeloproliferative disorder
- secondary (PCV > 70%) - chronic pulmonary disease, cardiac insufficiency, increased EPO associated with renal disease, dehydration (temporary)
What are toxic heterophils? What are 4 characteristics?
active heterophils in response to systemic illness
- basophilic cytoplasm
- abnormal granules
- degranulation
- vacuoles
What are 3 characteristics of lymphocytes?
- basophilic cytoplasm
- scalloped edges
- enlarged
(may look like monocytes!)
What are causes of leukocytosis and leukopenia? What is the best way to interpret on blood work?
- LEUKOCYTOSIS = infection/inflammation (chronic Aspergillosis, Chlamydia, or Tuberculosis), neoplasia, stress
- LEUKOPENIA = infection, immune dysfunction
leukogram trends, H:L ratio
What is the normal color of avian plasma? What are 3 common color changes?
clear
- GREEN = biliverdinemia - hepatic or renal failure
- YELLOW = lipemic - normal in hatchlings, post prandial in carnivorous birds, and reproductive females, or hepatic disease
- RED = hemolysis (artifact if PCV is normal)
When is lipemic plasma abnormal at all times?
in non-carnivorous birds
What are the 2 most helpful liver parameters used for avian biochemistry?
- AST - non-specific, elevated with vitamin E/selenium def, hepatocellular damage, toxins, presticides, or muscle damage
- bile acids - MOST RELIABLE, may not be raised with acute insult, 2 high readings indicate liver biopsy
What can cause false increase in bile acids? When are they most commonly low?
lipemia, hemolysis
cirrhosis
What 5 other liver enzymes can be helpful for avian biochemistry?1
- ALT - liver, muscle, kidneys; non-specific!
- ALP - liver, kidneys, intestines, bone; non-specific!
- GGT - biliary, renal epithelium; hepatic neoplasia (biliary carcinoma), cholestasis
- LDH - liver, kidneys, muscle
- GDH - elevated with severe liver disease
How is uric acid used for interpreting bloodwork in birds? What causes and increase and decrease?
produced in the liver and filtered by the kidneys (assessed renal function
- INCREASE - dehydration, acute renal failure, postprandial (carnivore > herbivore), may result in gout!
- DECREASE - hepatic disease
What is the most indicative of renal disease in birds?
elevated UA in at least two consecutive samples on a well hydrates and fasted bird
What are the most common causes of hyper/hyponatremia?
HYPERNATREMIA - increased intake, dehydration
HYPONATREMIA - renal disease, GI loss, end-stage liver disease, CHF, endocrine disease
(Na = major extracellular cation ingested in the diet and excreted by kidneys)
What are the most common causes of hyper/hypokalemia?
HYPERKALEMIA - increased intake, renal disease, severe tissue damage, adrenal disease, acidosis, dehydration, hemolytic anemia
HYPOKALEMIA - reduced intake, GI or renal loss
(K = major intracellular cation ingested in the diet and excreted by kidneys)
What are the major causes of hyper/hypochloremia?
HYPERCHLOREMIA - severe dehydration, excessive dietary salt intake
HYPOCHLOREIA - prolonged regurgitation/vomiting, DI disease, edema, CHF, excessive urinary loss, metabolic alkalosis
What are the major causes of hyper/hypophosphatemia
HYPERPHOSPHATEMIA - severe renal disease, nutritional secondary hyperparathyroidism, hypervitaminosis D, excessive intake, normal in young animals
HYPOPHOSPHATEMIA - anorexia, hypovitaminosis D, malabsorption, long-term glucocorticoids
(P = related to Ca levels, eliminated by kidneys)
How is total calcium calculated? What are levels interpreted with?
tCa = iCa (active, varies depending on sample, storage, and pH) + protein bound Ca, chelated Ca
albumin and protein
What are 6 causes of hypercalcemia?
- excessive vitamin D3 supplementation
- pre-egg laying (polyostotoic hyperostosis)
- osteolytic bone disease
- primary/secondary hyperparathyroidism
- neoplasia
- granulomatous disease