The effect of handling and transport on the concentration of glucose and cortisol in blood plasma of common carp

The aim of this contribution was to assess the degree of stress in common c arp (Cyprinus carpio, L.) exposed to handling and transport. Cortisol and g lucose concentrations in blood plasma were used as stress indicators. In so me cases, concentration of ammonia in blood plasma and relative weight of s pleen (SST) were used as well. Within handling, an effect of time pause (0; 2 and 5 min) between catching the fish from water and blood sampling for s tress indicators was checked. Another goal was to assess the effect of Meno cain anaesthetics on the stress indicators. An open system of a 10-hour tra nsport in a special long-distance live fish transport truck (Transport I a II), and a 2-hour transport in classic transporting tanks (Transport III) w ere compared. Temperature and oxygen concentration in water was measured du ring transport. After handling the fish prior to blood sampling (2 and 5 mi n pause), the cortisol concentration dropped significantly (p < 0.001) and the glucose concentration significantly (p < 0.001) increased compared to v alues in fish sampled immediately after catching. No effect of anaesthetics on cortisol concentration was proved. On the contrary, the glucose concent ration fell (p = 0.012) in the anaesthetized fish. After a 10-hour transpor t in a special truck (Transport I), a significant (p < 0.001) decrease of t he cortisol concentration was found, as well as a significant (p < 0.001) i ncrease in the glucose concentration in blood plasma. In the course of 10-h our transport in a special truck (Transport II), the majority of carp was f ound dead. Suffocation and ammonia autointoxication due to loading the fish with full digestive tract were the most probable causes of the fish mortal ity. After a 2-hour transport in transporting tanks (Transport III) both th e cortisol concentration and relative weight of spleen (SSI) dropped non-si gnificantly while glucose concentration in blood plasma significantly (p < 0.001) increased. Results showed that both handling and transport are impor tant stressors in the common carp. Preventive measures were proposed aimed at alleviating the negative effects of these stressors.