Gareth Difford: Measuring methane emission to breed for more climate friendly and profitable dairy cattle
PhD defence, Friday 28 September 2018, Gareth Difford.
During his studies, Gareth Frank Difford researched genetic mechanisms for breeding more feed efficient and climate friendly dairy cattle. In his studies he further developed and validated the ‘sniffer’ method for recording methane emissions on thousands of dairy cows during automatic milking under commercial conditions. He found that it is possible to breed for the cows which emit less methane, making them more climate friendly. He defined a practical way to find dairy cows which require less feed to give the same milk yield and meat as other cows in the herd and that it is possible to breed for these feed efficient cows. He found that breeding for more feed efficient cows also resulted in cows which emit less methane. Integrating genetics and microbiology, Gareth Frank Difford found that the microorganisms within the rumen which degrade the feed and produce methane, were also partially heritable and breeding for these microbes maybe possible in the future. He found a way to quantify how much variation in cow phenotypes are associated with the rumen microbes and called this ‘microbiability’ in analogy to heritability. By finding the microbiability and heritability of phenotypes it is possible to prioritize research into breeding or changes in the rumen microbial composition to direct changes to cow phenotypes.
The PhD degree is completed at the Center for Quantitative Genetics and Genomics (QGG), Department of Molecular Biology and Genetics, Science and Technology, Aarhus University and Wageningen University & Research, Wageningen, the Netherlands.
This résumé was prepared by the PhD student.
Time: Friday 28 September 2018 at 12.00
Place: Auditorium, AU-Foulum, Blichers Allé 20, 8830 Tjele
Title of dissertation: Genetic control of Methane Emission, Feed Efficiency and Metagenomics in Dairy Cattle
Contact information: Gareth Frank Difford, e-mail: gareth.difford@mbg.au.dk tel.: +45 871 57971
Members of the assessment committee:
- Professor Just Jensen, Department of Molecular Biology and Genetics, Aarhus University, Denmark
- Professor Peter W. G. Groot Koerkamp, Wageningen University & Research, The Netherlands
- Associate professor Erin E. Connor, Department of Agriculture, USA
- Professor Lene Lange, Danish Technical University, Denmark
Main supervisors:
- Senior Researcher Peter Løvendahl, Center for Quantitative Genetics and Genomics, Aarhus University, Tjele, Denmark
- Professor H. Bovenhuis, Personal chair at Animal Breeding and Genomics, Wageningen University & Research
Co-supervisors:
- Researcher J. Lassen, Center for Quantitative Genetics and Genomics, Aarhus University, Tjele, Denmark
- Senior Scientist Y. de Haas, Animal Breeding and Genomics, Wageningen University & Research
Language: The PhD dissertation will be defended in English
The defence is public.
The dissertation is available for reading at the Graduate School of Science and Technology/GSST,
Ny Munkegade 120, building 1520, rooms 128-134, 8000 Aarhus C.