EVALUATION OF THE CONTRAVES AL-820 AUTOMATED HEMATOLOGY ANALYZER FOR DOMESTIC, PET AND LABORATORY-ANIMALS

A comprehensive evaluation of the automated haematology analyser Contr aves AL 820 was initiated to determine the suitability of this instrum ent for veterinary purposes in domestic, pet and laboratory animal spe cies. The AL 820 (AVL Medical Instruments, Schaffhausen, Switzerland) is an impedance cell counter with automated threshold setting for rapi d adaptation to cell characteristics of different animal species, Stor age capability for up to 200 data sets with histograms is provided. Ex cellent precision, linearity and carry-over features of the AL 820 hav e been demonstrated in tests with rat, mouse, cat, dog, cattle and hor se blood samples. Accuracy of haemoglobin and haematocrit measurements with respect to reference methods was characterised by strong linear correlation. The patented cyanide-free AL 820 method for haemoglobin d etermination compared very well to the haemo-globincyanide reference m ethod. Accuracy of the red blood cell, haemoglobin, haematocrit, mean corpuscular volume, white blood cell count and platelet count paramete rs was generally good, when compared to the established laboratory rou tine method (the predecessor model AL 801) or to a high end automated haematology analyser (Abbott Cell-Dyn CD 3500). Although variation of platelet count measurements was greater than variation of all other pa rameters, it was considered acceptable particularly with respect to th e lack of excelling alternatives. Poor accuracy of feline platelet cou nts was attributed to overlapping size distribution of red blood cells and platelets in this species. The overall favourable acceptance of t he AL 820 was based on easy handling, simple maintenance and pronounce d flexibility of this instrument at an economical purchase price, A sa mple volume of 30 mu l and a throughput of up to 60 samples per hour a re distinct advantages and render the AL 820 suitable for medium-sized laboratories. With few exceptions, the instrument provides reliable r esults for all major animal species encountered in routine veterinary haematology.