Influences of type of anaesthesia on cortisol, beta-endorphin and heart rate in pigs
Gerard, H × Sensky, PL Broom, DM Perremans, S Geers, Rony #
Editions scientifiques elsevier
Veterinary research vol:27 issue:3 pages:219-226
Two experiments were carried out using a total of 20 growing pigs of approximately 20 kg in order to investigate the effect of different types of anaesthesia (metomidate versus ketamine) on plasma levels of cortisol and beta-endorphin on the heart rate. The animals were housed individually within a zone of thermal neutrality. Feed and water were available ad libitum. After becoming accustomed to human contact (being approached and touched), a catheter was implanted in the jugular vein, exteriorized in the neck region. This operation was performed under halothane anaesthesia. After recovery, hourly blood samples were taken over a 27 hour period, and cortisol and beta-endorphin concentrations were measured in the sample plasma. After this reference period, half of the animals were anaesthetized with metomidate, the other half with ketamine, and blood samples were taken at regular intervals. During a second experiment the heart rate was monitored after being anaesthetized as described before. An influence of the type of anaesthesia was observed on the plasma concentration of cortisol, but no effect was observed with respect to the beta-endorphin concentration. A fivefold increase of cortisol concentration was observed after injection with ketamine, while a twofold increase was observed after injection with metomidate. This finding suggests a suppressive effect of metomidate on the plasma cortisol levels. A fivefold increase was also observed for the beta-endorphin concentration after injection with either ketamine or metomidate. The increase in the heart rate was related to the awakening activity, which was more difficult after the ketamine injection.