Acknowledgements

The studies presented in this thesis were conducted in the Angiang University Experiment Station in Chau Phu district, Angiang Province, Vietnam, supported by the Swedish International Development Agency/Department for Research Cooperation with Developing Countries (Sida/SAREC).

I would like to express my gratitude to the Swedish International Development Co-operation Agency, Department for Research Cooperation (Sida-SAREC) for the financial support of this thesis research.

I would like to express my gratitude to Professor Brian Ogle, Director of the ‘Regional-SAREC MEKARN Sustainable Livestock Production Systems’ Project, Department of Animal Nutrition and Management, Swedish University of Agricultural Science, my supervisor, for valuable advice and useful guidance during the study period.

I would like to express my gratitude to Dr. Thomas Reg Preston, who helped me during the period of the study.

I would like to express my gratitude to Dr. Ngo Van Man, Regional Coordinator and Mr. Nguyen Van Cong for their valuable support.

I would also like to express my appreciation to all of the professors, associate professors, doctors and instructors who provided me with useful knowledge during the courses.

I would like to thank colleagues in Department of Animal Husbandry and Veterinary Science, Faculty of Agriculture and Natural Resources, Angiang University, who shared my work in the office during my research.  

I would like to give my best wishes to my parents, my older sisters and younger brothers for their sentiment; to my wife for her love and her sharing in all happiness and sadness; to my children daughter and son for their warmness given to me.