Biology Reference
In-Depth Information
Chapter 15
Validation of Thromboelastometry in Cattle
S. Falco, B. Bruno, A. Borrelli, A. Cagnasso, and A. D'Angelo
Abstract Thromboelastometry (TEM) and thromboelastography are useful tools
for the evaluation of the entire clotting process from the activation of plasmatic
factors until fibrinolysis. TEM has been validated in several domestic species but
not in cattle. In this study, we defined normal TEM values in adult cattle and in veal
calves; we then compared rates of coagulation in these two groups. Furthermore,
the precision of the instruments was evaluated. Finally, we studied the correlation
between the hematological and TEM results. In calves, we identified a faster
activation of plasmatic factors (shorter clotting times) and lower fibrinogenemia.
The precision of TEM on the bovine blood samples was good. Additionally,
hematocrit was positively linked to clotting time of the intrinsic and extrinsic
pathways, whereas fibrinogenemia was strongly associated with fib-TEM
®
tracing.
Keywords Bovine • Coagulation • Milk-fed veal calves • Reference range •
Thromboelastometer
15.1
Introduction
There exists a wide range of veterinary laboratory tests for blood coagulation
evaluation, each analyzing a specific phase of the coagulation cascade: primary
hemostasis, secondary hemostasis, and fibrinolysis. Unlike other tests, the
thromboelastometer (TEM)/thromboelastograph assesses the blood's viscoelastic
properties during all phases of clot formation. Additionally, through the addition of
specific reagents, the TEM allows for the selective study of the intrinsic pathway
(in-TEM
®
), the extrinsic pathway (ex-TEM
®
), and fibrinogen function (fib-TEM
®
)
(Luddington
2005
).
S. Falco (
*
) • B. Bruno • A. Borrelli • A. Cagnasso • A. D'Angelo
Dipartimento di Patologia Animale, University of Turin, Turin, Italy
e-mail:
sara.flc@libero.it
