Effect of Temperature on the Coagulation Activity of Blood Plasma in Rainbow Trout (Oncorhynchus mykiss), Common Carp (Cyprinus carpio), and North African Catfish (Clarias gariepinus) in vitro

Data from coagulograms of the rainbow trout Oncorhynchus mykiss (Walbaum, 1792), North African catfish Clarias gariepinus (Burchell, 1822), and common scaly carp Cyprinus carpio (Linnaeus, 1758), obtained by clotting methods at plasma incubation temperatures of 43, 40, 37, 24, 28, and 18°C, are analyzed. It is revealed that the internal pathway predominates in the activation of blood coagulation in catfish and carp, while rainbow trout was dominant among all the studied fish species with respect to the number of soluble fibrin-monomer complexes. Hypo- and hypercoagulable states have been established in the plasma hemostasis of the studied fish species in vitro at both low and high temperatures of the reaction medium. Fibrinogen and antithrombin III are thermolabile at temperatures other than 37°C. Correlation and regression analysis has shown that the prothrombin time (PT) is most closely related to changes in temperature in carp and the activity of fibrinogen and antithrombin III in catfish. The 50% change in PT can be explained by the influence of the temperature factor and the fibrinogen and antithrombin III activity by 77% and 52%, respectively. The revealed patterns may become a basis for determining the limits of thermal fish adaptation and developing heat stress biomarkers.