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
What are 6 causes of hypocalcemia?
- alkalosis
- malabsorption
- pancreatitis
- chronic egg laying
- renal failure
- nutritional
What are the most common causes of elevated amylase? CK?
AMYLASE - acute pancreatitis, neuropathic gastric dilatation, severe enteritis
CK - traumatic venipuncture or muscle trauma/pathology
What are the most common causes of hyper/hypoglycemia?
HYPERGLYCEMIA - post-prandial, excitement/stress, corticosteroid therapy, pancreatitis, DM (rare in birds)
HYPOGLYCEMIA - anorexia, malnutrition, severe hepatic disease, septicemia
What makes up total protein?
ALB + GLOB + fibrinogen fractions
- compare ALP to GLOB
What causes increased/decreased ALB?
INCREASED = dehydration, normal in reproductively active females
DECREASED = reduced amino acid intake, reduced production, increased GI/renal loss, burns, chronic infection, hepatic disease
(produced in the liver, responsible for colloidal oncotic pressure)
What are the most common causes of hyper/hypoglobulinemia?
HYPER - inflammation
HYPO - rare!
(responsible for immunity, can calculated, commonly combined with protein electrophoresis for a more detailed diagnosis)
What are the most common causes of increased alpha beta, and gamma inflammatory proteins?
ALPHA - systemic inflammation, malnutrition, renal disease
BETA - chronic liver/renal disease, chronic inflammatory disease (Aspergillosis, Chlamydia), egg production
GAMMA - monoclonal = egg laying hands, lymphoid/plasma cell neoplasia
What are the most common causes of decreased alpha and beta inflammatory proteins?
- hepatic insufficiency
- starvation
- blood loss
- protein loss
What types of inflammation are associated with alpha, beta and gamma proteins?
ALPHA + BETA = acute, severer inflammation/infection
BETA + GAMMA = chronic, acitve inflammation/infection
ALPHA + BETA + GAMMA = severe, chronic/active or acute severe inflammation/infection
What are pathopneumonic changes of blood work in egg-laying females?
- 1.5-2x inflammatory protein increase
- increased iCa
When is cytology an especially helpful diagnostic in avian species?
GI disease
- oral swab for Trichomonas spp
- crop wash for Candidal albicans
What is commonly required for the proper diagnostic views on avian radiographs?
brief anesthesia or sedation
- commonly use gas anesthesia
What 2 contrasts are commonly used for avian radiography?
- PO barium - highlights GIT (SI by 30-60 mins, LI by 60-120 mins, faster in raptors)
- IV iodine - urophragy or angiography
What fractures are most common in avian pets and raptors?
PETS = tibiotarsal
RAPOTRS = coracoid (+/- other girdle bones)
Fractured coracoid:
slight displacement appreciated
- typically highlighted by a 45 degree craniocaudal/DV view
What 3 disease processes are diagnosed on radiographs?
- metabolic bone disease - check long bones, like tibiotarsus
- polyostotic hyperostosis
- (septic) arthritis
In what birds is polyostotic hyperostosis most common? How does it appear on radiographs?
ovulating females
increased opacity of medulla in pelvic > thoracic limbs due to calcium deposition
How does septic arthritis appear on radiographs?
- enlarged joint space
- proximal/distal soft tissue swelling
- lysis of articular bones
What makes interpreting the coelomic cavity of birds difficult? What structures are labeled?
no diaphragm = increased summation
- lung
- heart
- liver
- gizzard - gravel within is normal
- intestines
- glandular stomach (proventriculus)
- spleen
- kidney
- gonad
What structures are highlighted in this radiograph?
- lungs
- heart
- liver
- ventriculus - L pelvic acetabulum
- intestines
(radiolucency = air sacs)
liver + heart - cardiohepatic silhouette interpreted together
What position is preferred for evaluating dorsal lung fields? How does it normally appear?
lateral
honeycomb - loss = infiltrative disease (pneumonia)
How does the trachea compare in different species? What location is of clinical importance?
length varies
SYRINX - found at tracheal bifurcation, male waterfowl have an osseous bulla for sound resonance
How are air sacs best appreciated on radiographs? How do they appear?
DV - lateral to cardiohepatic silhouette
thin-walled and empty
What is occurring in this radiograph?
complete soft tissue opacity within coelom —> cannot see air sacs, likely air sacculitits
What is occurring in these radiographs?
thickened air sac walls = air sacculitis —> Aspergillosis
What is unique about radiographs in pelicans?
have natural SQ emphysema
- may be indicative of air sac rupture in other birds
Where is the avian heart located in the coelomic cavity during radiographs?
cranial coelomic cavity
How is the avian heart assessed on radiographs?
VD - hourglass shape of the cardiohepatic silhouette
- caudal masses will push GIT cranially, altering the cardiohepatic silhouette
Cardiomegaly:
less defined cardiohepatic silhouette - more of a rectangle compared to the normal hourglass
What other part of the cardiovascular system can be appreciated on radiographs?
great vessels - atherosclerosis common in birds fed high fat diet with a sedentary lifestyle
How is the crop most commonly appreciated on radiographs?
with contrast - can identify food material and FB
- not present in all species
Where is the proventriculus found on radiographs?
- LATERAL = dorsal to the heart
- VD = left side of the hepatic portion of the cardiohepatic silhouette
Where is the ventriculus found on radiographs?
left of midline at the level of the acetabulum on VD
- normally contains grit (bone opacity)
- asses for FB
Proventriculus, radiograph:
contains normal amount of grit
What is required to assess other parts of the avian GIT?
contrast —> intestines, cecum, cloaca
- highly superimposed and not well-highlighted
What is the normal size of the cardiohepatic silhouette?
should fit between borders of the scapulae
When is the avian spleen most commonly seen? How does it appear?
splenomegaly associated with certain disease processes —> Chlamydia
round soft tissue opacity cranial to the femur just above the proventriculus
Where are kidneys and gonads found on radiographs?
KIDNEYS = ventral to the spine with the cranial subdivision cranial to the acetabulum, surrounded by gas opacity (can be mineralized with gout)
GONADS = not always visible, cranioventral to the cranial division of the kidney
Is ultrasound commonly used as a diagnostic in avian species?
not typically - birds have a lot of air within their body, which does not show well
