Exotics Flashcards
Risks of rabbit venipuncture
Spinal fractures, respiratory disease and stress
How do you calculate a safe blood volume to take from small mammals?
1% bodyweight or 10% circulating volume
Does rabbit blood clot quickly or slowly?
Quickly
Blood samples to take from a rabbit
EDTA for haematology
Lithium heparin for biochemistry
Fluoride oxalate for glucose
Two fresh blood smears
Glucometer reading
Blood tube for biochemistry in all exotic animals
Serum
Lithium heparin if restricted on volume
What should you do to venipuncture site in rabbits ~30m before sample is taken?
Emla cream for local anaesthetic
Venipunture sites in a rabbit
Marginal ear vein
Jugular
Cephalic and saphenous veins
Location for guinea pig blood samples
Cephalic vein
Cranial vena cava (large blood draws)
Location for small rodent venipuncture
Lateral tail vein (warm tail first)
Lateral saphenous vein (under GA)
Cranial vena cava
Ferret venipuncture sites
Jugular vein
Cranial vena cava
Does GA increase or decrease PCV in a ferret?
Decrease
Hedgehog venipuncture sites considering their thick skin
Femoral vein (easiest)
Cranial vena cava
Jugular vein (hard to visualise with thick skin)
Which venipuncture sites are likely to require GA in a hedgehog?
All of them
Technique for cranial vena cava blood sample
GA
Patient in dorsal recumbency, head extended
Needle placed at notch where first rib meets manubrium (uppermost sternum)
Advance towards contra-lateral hindlimb
30 degree angle until blood flush
Lymphatics in reptiles are closely linked to blood vessels, what is the problem with contamination of blood samples?
Affects PCV and some biochemistries
Is blood pressure in reptiles high or low?
Low, blood draws slowly
What must you always do when blood sampling from reptiles?
Take a fresh blood smear
Most suitable site for lizard venipuncture
Ventral coccygeal vein (1/3rd down tail to avoid hemipenes and anal glands, ventral or lateral approach)
In which size of snakes is it difficult to obtain a blood sample from the ventral coccygeal vein?
Small snakes
Sites for obtaining a blood sample in snakes
Ventral coccygeal vein
Heart (large volume)
Palatine (prone to haematoma)
Tortoise blood sampling sites
Jugular vein
Sub-carapacial vein
Dorsal coccygeal vein
Which tortoise venipuncture method doesn’t require GA or sedation as the neck can be extended or retracted?
Sub-carapacial vein
How do you calculate a safe volume of blood to collect from a reptile?
5-8% of bodyweight or 10% blood volume (but usually presented as anaemic so take half this volume to be safe)
What is the problem with EDTA for reptiles?
Haemolyses red blood cells
What is the anticoagulant of choice in exotic species?
Lithium heparin
What should you always do when taking blood samples for exotic species?
Make two fresh blood smears
Why is thorough skin preparation for venipuncture important in exotic species?
Skin is often heavily contaminated
Is anisocytosis and polychromasia a normal or abnormal finding in a rabbit? Why?
Normal and common due to short erythrocyte life span (57-67 days)
Lymphoid cell differences in rabbit blood compared to dog/cat blood
Heterophils (neutrophils) have granular cytoplasm
Basophils common
Neutrophil to lymphocyte ration 1:1
What cell is this in rabbit blood?
Heterophil (neutrophil)
What cell is produced by thymus under oestrogen stimulation in guinea pigs which is found in the blood?
Kurloff cell
Most abundant cell in guinea pig blood
Neutrophil
Do ferrets have blood groups?
No
Are ferret HCT, HB and RBC counts usually higher or lower than dogs/cats?
Higher
What is the difference between eosinophils and neutrophils in ferret blood?
Neutrophil: small, pale-red granules
Eosinophil: granules rounded and bright red
Which cells are nucleated in reptiles that aren’t in other species?
Erythrocytes and thrombocytes
Why shouldn’t you take blood samples too regularly in reptiles?
Takes 4 months to replenish
What cell type is this in a reptile blood sample? (Predominant cell type in reptiles)
Heterophil (equivalent to a neutrophil)
What time of year are lymphocyte levels lowest in reptiles?
Winter
What time of year are eosinophil levels lowest in reptiles? (Picture also shows two heterophils)
Summer
Do basophil levels in reptiles vary through seasons?
No
What cell in blood is unique to reptiles?
Azurophils, more common in snakes
When do monocytosis and azurophilia occur in reptiles?
Inflammation
Granulomatous disease
What cell is this in a reptile blood smear?
Monocyte
Primary lymphoid organs in birds
Bursa of Fabricius and thymus
Secondary lymphoid organs in birds
Spleen, intestinal lymphoid tissue, bone marrow
What cells develop in the thymus?
T-lymphocytes
Where are T and B-lymphocyte precursors produced in birds?
Embryonic yolk sac and bone marrow
What cell type is developed in the bursa of fabricius?
B-lymphocytes
How is a spleen in a bird different to a mammal?
Not a blood reservoir (smaller)
Spleen function in bird
Lymphopoiesis and antibody production
What cell type is the arrow pointing to in this avian blood smear?
Erythrocyte
What cell type is the arrow pointing to in this avian blood smear?
Thrombocyte
How quickly is blood loss replenished in birds?
Days
Are immature red blood cells a normal or abnormal finding in birds?
Normal (mild polychromasia/anisocytosis)
How are avian thrombocytes different to mammalian thrombocytes?
Phagocytic functions
Weaker clotting function
Originate from stem cells not megakaryocytes
Do birds have heterophils or neutrophils?
Heterophils (round cells, lobed basophilic nucleus, oval cytoplasmic granules, colourless cytoplasm)
Functions of heterophils in birds
Phagocytosis, bacteriocidal, acute inflammation
What cell type is labelled E in this avian blood smear?
Eosinophil
What cell type is labelled B in this avian blood smear?
Basophil
What are the lymphocytic bird species? (70% lymphocytes)
Amazon parrots and canaries