Improving productivity in extensively managed grazing ruminants

Supervisors: Prof Jamie Newbold, Dr Kenton Hart ([Email Address Removed], [Email Address Removed])
Industrial partner: Caltech-Crystalyx

The UK uplands carry around 12 million breeding ewes and more than a million suckler cattle (representing over 60% of the UK total). The nutritional quality of grazed herbage varies throughout the grazing season however, the feeding of supplementary concentrates to grazing livestock is not a practical option as it is time-consuming and expensive. Low moisture feed blocks are a commercially available product that allows all animals, extensive or intensive, to be supplemented with readily available energy and minerals. Recent results obtained in grazing heifer trials suggest that gains in performance are some 5-7 X higher than would be predicted based on block intake alone. We are looking for a talented and motivated scientist to help understand why this occurs.
We have demonstrated that animals offered low moisture feed blocks consistently have stimulated forage intake and in turn an increased growth rate compared to control animals. Whilst the exact reasons for this increased intake are unknown, ongoing research seems to show that rumen function including fibre digestion is enhanced in animals with access to low moisture feed blocks, possibly due to the sugar/protein and or mineral/vitamin content of the block stimulating rumen microbial populations. Here we will further investigate the effects on rumen fermentation using a combination of carefully designed trials in sheep, coupled to the use of in vitro rumen fermentation models and modern molecular techniques (bar coded next generation sequencing of 16 and 18S rDNA) to describe and better understand the effects on the rumen microbial population and fermentation. Significant expertise in the formulation, production and chemical/biophysical characterisation of low moisture blocks exists within Caltech-Crystalyx and in phase 2 of the project this will be used to formulate modified blocks (based both on changing the relative concentration/source of sugar, protein and mineral/vitamins and by changing the parameters used in block manufacture) that will then be further evaluated in in vitro models and finally in intact animals to futher elucidate the mode of action of the product
This PhD studentship provides an opportunity to join a world-class animal science/ rumen microbiology group equipped with cutting edge genomic and metabolomics facilities. The student will gain expertise in both animal and in vitro fermentation coupled with training in molecular microbiology and bioinformatics. They will also benefit from a placement with Caltech-Crystalyx, an international producer of low moisture feed blocks, where they will gain experience relevant to future employability in applied aspects of animal science, end user requirements and product formulation.