Optimising the cost-effectiveness of supplementary feeding in sheep meat production systems

Summary

The project described in this report consisted of three major sections and is reported in that fashion. The first part of the project, comprising Section A of this report, consisted of research to develop a new, alkane-based technique which could be used to estimate the supplement intake of grazing animals, since a major impediment to assessing, modelling and thus predicting the response of animals to supplements was the difficulty of estimating the. interaction between herbage and supplement intakes. While methods for estimating supplement intake already existed, the development of an alkane-based method would allow it to be combined with the existing alkane method for herbage intake, thus permitting the estimation of both herbage and supplement intake from the same set of analyses.

The second section of the project (Section B of this report) consisted of studies on tbe response of live weight, body composition and wool growtb of large lambs to diets consisting of near- or sub-maintenance intakes of medium-quality roughage with or witbout protein supplements of differing quality and rumen degradability. The final section oftbe project (Section C oftbis report) involved investigations of the need for and nature of modifications to tbe decision support tool GrazFeed, so tbat it might better predict the responses to supplements of the kind fed in tbe second section oftbe project and thus capture the biological information generated in that section.