The overall aim of the present thesis was to improve the welfare of animals in research by refining the perioperative nursing and anaesthesia care of growing pigs in accordance with the 3Rs, replace, reduce and refine. Forty-six pigs were trained during a 14-day acclimatisation period to accept blood and urine sampling and ultrasound examination. A polymer coated catheter for repeated blood sampling from the jugular vein was assessed. The effects of zolazepam-tiletamine and medetomidine (ZTMe) was compared with midazolam, ketamine and fentanyl (MiKF) regarding the quality of induction and physiological variables in a subsequent total intravenous anaesthesia (TIVA) with MiKF. A combination of zolazepam-tiletamine, dexmedetomidine and butorph...