Novel techniques for understanding lipid metabolism in ruminants and implications for human health.

Supervisors: Prof KJ Shingfield ([Email Address Removed]), Dr S Huws ([Email Address Removed]) and Prof ND Scollan ([Email Address Removed]), IBERS and Dr K. Kliem and Prof DI Givens, University of Reading.

Efficient food production is central to meeting the demands of an expanding global population against a background of constrains on water and land availability and the need to lower greenhouse gas emissions. Ruminants are an essential component of our future food security due to their ability of converting fibre rich feeds into high quality human foods. However, ruminant foods are often perceived as unhealthy, because the fat is rich in saturated fatty acids (SFA), contains low amounts of polyunsaturated fatty acids (PUFA), and a source of trans fatty acids (TFA). Excessive consumption of SFA and TFA are risk factors for cardiovascular disease and thought to contribute to insulin resistance and development of certain cancers This project will use new and exciting techniques to better understand what happens to dietary fats in the ruminant animal and how this information can be used to alter the quality of meat and milk for improved human health.

Even though the diet of ruminants is rich in PUFA, these are not transferred into meat and milk due to transformations in the rumen in a process referred to as biohydrogenation (BH) catalysed by enzymes produced by rumen bacteria. However, biohydrogenation of PUFA to SFA is incomplete and intermediates, often TFA are formed. Following digestion and absorption, the products of BH are incorporated into meat and milk and enter the human food chain. Several BH intermediates are known to inhibit fat synthesis in mammals, including man, while others are proven anti-carcinogens in animal models.

The pathways of BH and the factors affecting them are poorly understood. This project will, in the first instance, involve performing experiments with 13C labelled substrates and deuterium oxide with mixed and pure strains of rumen bacteria to generate new information on the mechanisms responsible and products formed during BH. It is anticipated these experiments will be extended to whole animal studies. IBERS is in the unique position of holding a biobank of ruminal microorganisms, a state-of-the-art mass spectrometry laboratory and metabolism unit for sheep and cattle, underpinned by next generation sequencing facilities and bioinformatics expertise. IBERS has unparalleled opportunities for training and research linking plant, microbial and animal genomes crucial to understanding the biology of ruminants.

This PhD studentship provides an opportunity to gain world-class expertise in microbiology, nutrition, physiology and biochemistry. Training will be given in microbial techniques, lipid analysis and animal experimentation. The successful candidate will be supervised by a team of Internationally recognised scientists, with global research networks whom also work in close collaboration with numerous commercial partners. This ensures that the student will gain experience relevant to developing a successful career in academia or industry.