EASTBIO Optimising amino acid nutrition in periparturient dairy cows

In dairy cows, milk protein production accounts for only 20-30% of dietary protein intake. Inefficient use of dietary protein reduces dairy farm profitability and can have negative effects on the environment by increasing greenhouse gas emissions, contributing to eutrophication of water courses and reducing air quality. Reliance on imported protein sources such as soya also has worldwide environmental impacts that the dairy industry is seeking to reduce.

Precision nutrition has the potential to improve productivity and minimise negative environmental effects of livestock farming. Applied to the protein nutrition of dairy cows, precision nutrition means delivering an optimum balance of absorbable amino acids, from dietary proteins, to achieve high rates of milk protein output and low rates of nitrogen excretion in faeces and urine. In addition, it is now known that amino acids exert multiple effects on the rapidly changing physiology of dairy cows before and after calving, acting as both substrates for protein synthesis and signals for gene transcription.

Interactions between amino acid nutrition at different points in the lactation cycle are poorly understood, although recent evidence shows that amino acid nutrition immediately before calving affects the response of cows to amino acid nutrition once lactation has commenced. In turn, amino acid nutrition early in lactation may have carryover effects into later lactation, opening the prospect of improving the overall efficiency of nitrogen utilisation by targeting feed supplements at specific periods of the lactation cycle.

The overall aim of this project is therefore to optimise the temporal distribution of absorbable amino acids across the lactation cycle in the dairy cow.

The student will be based at the SRUC South and West Faculty in Dumfries, with time also spent at The Royal (Dick) School of Veterinary Studies and the Roslin Institute, University of Edinburgh. They will take part in an extensive training programme which will ensure competence to work at interdisciplinary interfaces. Supported by academic and technical staff, the student will design, implement and analyse dairy cow nutrition experiments in which dietary absorbable amino acids are supplied at different stages of lactation (before and after calving, and at peak milk production), with measurement of responses in milk yield, composition and efficiency of nutrient use. The student will establish, in SRUC, non-invasive methods to isolate milk secretory cells that have been developed in other institutions and use those cells to study gene expression. The project will therefore deliver training across a broad range of analytical, laboratory, whole animal and data analyses experimental methods.

The project provides an opportunity to work closely with a leading UK-based animal nutrition company to improve the management of amino acid nutrition through the evaluation of feed materials and formulation of rations for dairy cows, and to participate in the process of knowledge exchange to drive improvements in farming practice. It is expected that project results will be translated into farming practice by the commercial partner in the form of new nutritional products and services.
Applicants should download the required forms from http://www.eastscotbiodtp.ac.uk/how-apply-0 and send the following documents to [Email Address Removed]:
a. EASTBIO Application Form
b. EASTBIO DTP Equality Form
c. CV
d. Academic transcripts (a minimum of an upper second class or first class honours degree or equivalent is required for PhD study
e. Two references should be provided by the deadline using the EASTBIO reference form (http://www.eastscotbiodtp.ac.uk/how-apply-0). Please advise your referees to return the reference form to [Email Address Removed].
f. If you are nominated by the supervisor(s) of the EASTBIO PhD project you wish to apply for, they will provide a Supervisor Support Statement.