SAEVA Congress 2018 Proceedings | 12-15 February 2018 | ATKV Goudini Spa
HAEMATOLOGY AND PLASMA BIOCHEMISTRY IN EQUINE ATHLETES
Warwick Bayly College of Veterinary Medicine , Washington State University Pullman , WA 99164-7010
Over the years , veterinarians have been particularly interested in the results of hematological and serum or plasma biochemical testing of appropriate specimens collected from performance horses , as an aid to the clinical evaluation of disease state , exercise intolerance , response to training , or assessment of performance potential . Much of this is because samples are easily obtained and laboratory facilities are usually readily accessible . Despite this widespread use , interpretation of the resultant data is still subject to a number of limitations . This is especially true with respect to hematology , in which a broad range of psychological , physiological , environmental , and individual factors can influence the results of tests . For example , consideration must be given to the age of the horse and the amount of training it has received , when the sample was taken in relationship to exercise , and the type of event in which the animal is engaged . Further indications of this are seen in the wide disparity of results reported from studies of horses in training and following competition . Distinctions must be made between findings in racehorses and those for horses involved in " submaximal " events like combined training and endurance races .
HAEMATOLOGY ( see table 1 )
The hematological profile of the horse in training is in a dynamic , rather than static state . Consequently , results from repeated testing of a given horse may fluctuate markedly , and a wide range of supposedly " normal " values exist for these animals . The variability which can exist is largely a reflection of the capacity of the equine spleen to store erythrocytes and leukocytes ( particularly lymphocytes ). The extent to which this organ mobilizes these cells is a function of sympathetic tone and circulating concentrations of epinephrine . The spleen is very sensitive to alterations in these factors and results of equine hematological testing may vary accordingly . Therefore , it is of major importance that the veterinarian be aware of the many factors that can provoke epinephrine secretion and affect the state of the sympathetic nervous system , and take care to consider these factors when obtaining blood samples and interpreting the results of their analysis .
Although the use of automated cell counters has done much to reduce the variability of results , differences in the handling of samples and the way blood smears are 60