The main resaerch activities of David Kenny involve cattle nutrition and its influence on (i) carcase composition and quality (ii) ruminal methanogenesis (iii) reproductive performance. He has also recently developed an interest in cattle genetics with emphasis on functional genomics and the identification of new selection traits for improved biological and economic efficiency as well as product composition in beef cattle production systems. He has developed research programmes in the areas of meat quality, energetic efficiency, environmental impact of beef cattle production as well as cow fertility. Currently, he is leading two major nationally funded projects and a principle investigator on a further four. He currently supervise the highest number of postgraduate students (n=19) in the School. Some of my recent work on elucidating the dietary and molecular mechanisms controlling the accumulation of human health promoting fatty acids in beef has shown, for the first time, potential problems associated with attempting the simultaneous accentuation of certain nutraceuticals, conjugated linoleic acid (CLA) and the n-3 polyunsaturated fatty acids (n-3 PUFA) in beef tissue. His work has investigated dietary strategies to improve the concentrations of these beneficial fatty acids in meat and milk with a view to improving the nutritional content of these ruminant products as well as potentially, the economic return to the producer. Indeed his group has reported increases in the CLA and n-3 PUFA concentration of beef of two fold and 10 fold respectively through targeted diet supplementation. However, his work was also the first to show potential counterproductive effects on CLA synthesis through attempting to augment these two groups of fatty acids simultaneously in muscle tissue. In order to attempt to elucidate the biological mechanism behind this inhibition a molecular examination of the biochemical processes leading to CLA synthesis was adopted and it was found that n-3 PUFA inhibit the transcription of genes coding for key enzymes and transcription factors regulating CLA synthesis. This work has recently been published in the Journal of Animal Science. In order to further test the interaction between dietary nutrients and gene transcription on fatty acid synthesis and fat metabolism in cattle, we recently developed a bovine primary adipocyte cell line. The development and validation of this novel cell line has been well received by the scientific community and is detailed in a manuscript recently published by the journal Animal. Finally, he has also developed a strong research programme in the area of strategies to reduce enteric methane emissions from cattle. For example, some of his work to date has shown that strategic supplementation of cattle diets with sources of  long chain PUFA can reduce ruminal methane emissions by up to 40%, while increasing muscle concentrations of CLA as well as feed efficiency.

Publications

• Childs, S., Hennessy, A., Sreenan, J.M., Wathes, D.C., Cheng, Z., Stanton, C., Diskin, M.G and Kenny, D. A. (2008). Effect of level of dietary n-3 polyunsaturated fatty acid supplementation on systemic and tissue fatty acid concentrations and on selected reproductive variables in cattle. Theriogenology. 70: 595-611.
• Waters, S.M., Kelly, J.P., O’Boyle, P., Moloney, A.P. and Kenny, D.A. (2008). Effect of level and duration of dietary n-3 polyunsaturated fatty acid supplementation on the transcriptional regulation of ∆-9 desaturase in muscle of beef cattle. Journal of Animal Science. 87: 244-52.
• Minchin, W., O’Donovan, M.A., Kenny, D.A., Monahan, F.J., Shalloo, L. and Buckley, F. (2009). Effect of grass silage and concentrate based finishing strategies on cull dairy cow performance, carcass and meat quality characteristics. Meat Science. 81: 93-101.