PATHOLOGY - Equine Anaemia Flashcards
How does horse breed influence PCV?
Breeds used as racehorses are going to have a higher PCV compared to breeds used for leisure horses etc
How can exercise and stress affect an equine blood sample?
Exercise and stress cause splenic contraction which will increase the PCV
How can sedation affect an equine blood sample?
Sedation causes splenic relaxation which will decrease the PCV
What should you be aware of when using EDTA tubes to collect blood samples from horses?
In horses, erythrocytes and platelets tend to form rouleaux (aggregates) which can affect haematology results
Which blood tube should you use if you want to carry out an accurate platelet count in horses?
Sodium citrate tube
Which infectious agent should you test for in anaemic horses?
Piroplasmosis (not currently in the UK unless horse has been imported from an endemic area)
What can be done to prevent importing piroplasmosis into the UK?
Screen all imported horses for piroplasmosis using ELISA and PCR
What are the clinical signs of acute anaemia in horses?
Tachycardia
Tachypnoea
Hyperpnoea
Pale mucous membranes
What are the clinical signs of chronic anaemia in horses?
Exercise intolerance
Weight loss
Haemic murmur
What is a haemic murmur?
A haemic murmur is a heart murmur due to the decreased viscosity associated with anaemia which will result in turbulent blood flow
What are the two main causes of non-regenative anaemia?
Primary bone marrow disease
Secondary failure of erythropoiesis
Where are bone marrow samples taken from in horses for bone marrow evaluation?
Sternum
What is the most common cause of secondary failure of erythropoiesis in horses?
Chronic disease resulting in chronic inflammation
What are the two main forms of regenerative anaemia?
Haemorrhagic anaemia
Haemolytic anaemia
What are the distinguishing features of regenerative anaemia on a horse blood smear?
Anisocytosis
Howell-jolly bodies
(T/F) Horses do not have reticulocytes
TRUE.
What are the distinguishing features of regenerative anaemia on horse haematology?
Increased mean corpuscular volume (MCV)
What is the average blood volume in horses?
80 - 100ml/kg (depending on if they are warm or cold blooded, warm is on the higher end)
What can you do to determine if an anaemia is regenerative in a horse that has suffered acute haemorrhage?
You can take sequential blood samples to measure the PCV and the total protein and see if there is improvement
How quicky should PCV begin to improve following acute haemorrhage?
PCV should improve by 1% every 3 days following acute haemorrhage