CO and N2 are not humane alternatives to CO2 euthanasia in rats
Charlotte Calvet·Petra Seebeck·Philipp Villiger·C Thöne-Reineke·Tim Buchholz·Boris Gourévitch·Carsten A. Wagner·Francesco Prisco·Felix Gantenbein
Carbon dioxide (CO2) is commonly used for rat euthanasia, but its potential negative side effects call for alternatives causing less distress while providing a fast and reliable loss of consciousness (LOC). Euthanasia with CO2 is currently performed in a highly non-standardized manner with different CO2 volume displacement rates/minute (VDRM) ranging from replacing 30 to 70% of the chamber volume with 100% CO2 per minute. Therefore, we evaluated euthanasia with 100% CO2 at 30% and 70% VDRM as we