Progress in the replacement of animal experiments in the quality control of clostridial vaccines

Animal experiments still play a central role in the quality control of vaccines. Generally, performance of these experiments is provided by law and laid down in the European Pharmacopoeia. Classical vaccines, the efficacy of which is calculated in International Units, require a very high number of experimental animals for quality control testing. The testing mainly consists of infection and intoxication experiments causing extreme suffering of the animals involved. This classical product group includes clostridial vaccines which are used to a great extent in veterinary medicine in particular. Within the last years, considerable efforts have been made to reduce the number of animal experiments in this field, lower the number of animals, and decrease the suffering of the animals during testing. Several research projects for the development and validation of alternative methods have been initiated. Furthermore, the 3R Concept (Replacement, Reduction and Refinement) is increasingly taken into consideration when developing or revising legal provisions. This led to various improvements regarding animal welfare in the quality control of clostridial vaccines.