ACKNOWLEDGEMENTS

A grant from the ABS (Applied Bioscience - Bioengineering - Food & Nutrition, Environment) Graduate School made it possible for me to concentrate on my Ph.D. work for four years. This work was also supported by grants from the Academy of Finland, the Faculty of Veterinary Medicine, the Walter Ehrström Foundation and the Finnish Veterinary Foundation.

The studies included in my thesis are a result of team work. Therefore, I would like to thank the following persons whose contribution was crucial during the past four years: The supervisor of my thesis, Prof. Hannu Korkeala, provided experienced guidance, opinions and encouragement, all in appropriate amounts. Dr. Johanna Björkroth was there to advise me when I took my first steps into the world of DNA-based typing. Dr. Sebastian Hielm, my co-worker in our botulinum research team, shared successes and failures with me and was there to give a hand whenever I needed a replacement. The invaluable technicians of our team were Ms. Kirsi Ristkari, Ms. Maria Stark and Ms. Sirkku Ekström. Their diligent hard work and flexibility facilitated the accomplishment of this work in four years. Ms. Johanna Seppälä provided efficient secretarial assistance which made many things easier.

I would also like to thank Dr. Susan Maslanka and Prof. Constantin Genigeorgis for reviewing my thesis and Dr. David Trees for correcting the English spelling and style of my manuscripts and summary.

This is not the end; this is only the beginning. It is time to move on and confront new challenges.