EFFECT OF HORMONE-INDUCED STRESS ON CARP (CYPRINUS CARPIO) COAGULOGRAM

Abstract

Carp (Cyprinidae) is one of the dominating and most valuable fish species in fish farming. Under conditions of high-intensity cultivation, fish are systematically exposed to extreme factors that cause stress reactions, accompanied by changes in the functional state of the defense of the body systems and exert impact, primarily, on hematological parameters. The hemostatic system is one such defense systems, which counteracts bleeding through a coagulation mechanism. Hemocoagulation follows the same pattern in all vertebrates, from jawless fish to mammals, and represents an ancient adaptation of animals to stressful conditions, often associated with blood loss in nature. This research aimed to study the effect of hormone-induced stress on plasma (secondary) hemostasis in fish. Given the data fragmentation and differences in methodology and conditions, the lack of standardization in studying hemostasis in fish, especially in critical conditions, this problem remains not fully disclosed in global science. The article presents the results of studying carp (Cyprinus carpio) coagulogram parameters under the influence of acute and chronic stress responses, simulated by injections of synthetic cortisol analogs (dexamethasone for short-term stress, and betamethasone for chronic stress) during 21 days. The dynamics of these indicators were analyzed in comparison to intact fish. It has been established that by accelerating the activated partial thromboplastin time, prothrombin time, and increasing the amount of fibrinogen in the blood of fish, blood coagulation processes were clearly accelerated in all groups of animals tested by the last day of the experiment. The dynamics of other parameters, such as the content of soluble fibrin monomer complexes or antithrombin III content, indicated the simultaneous development of hypercoagulation processes in some groups. Assumptions have been made to explain the pattern of changes observed not only in treated fish but also in control animals.