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Studies were made on two perennial ryegrassdominant swards of the effects of cutting and grazing systems ou herbage production. A motor scythe was used for cutting and sheep in small enclosures for grazing. In both systems, herbage production was measured hy a ground-level sampling technique, using sheep shears, and the difference between pre-treatment and post-treatment herbage was expressed as 'utilized yield'. Correction for soil contamination is ensured by quoting all results on an organic-matter basis.Grazing treatments averaged 14-16% more organic matter and 36-45% more crude protein than cutting treatments in both experiments. These differences were ascribed to recycling of N under grazing. Infrequent defoliation gave higher yields than frequent, and severe defoliation higher yields than lenient under both cutting and grazing systems. The trends shown by cutting and grazing intensities are comparable and can be quantified.There is need to examine closely the relationships between the effects of cutting and grazing techniques on herbage production, since such knowledge would allow a more accurate prediction of the relevance to the grazing situation of results obtained under cutting.

An experiment was condncted to measure the effects of differrat ryegrass companion grasses and red-clover varieties on the productivity of red-clover swards. Three sOage harvests per year were taken over a 2-year period.The addition of a companion grass increased total herbage yields; S24 perennial ryegrass gave the highest herbage yield over the two years, followed by Reveille perennial ryegrass. Because of lack of persistence, Tetila Italian ryegrass yielded poorly the second year. A companion grass had Uttle effect on red-clover yields in the mixed swards but improved percentage digestibility of the OM of the total herbage and lowered the CP percentage. Its presence also reduced the ingress of unsown species.The variety of red clover used had little effect on total herbage yields or red-clover yields in the first harvest year. In the second year, Hungaropoly and Tilo persisted better and so gave higher total herbage yields and red-clover yields than Dorset Marl or Essex. The fall in total herbage yields from the first to the second year was entirely due to a fall in red-clover yield since yields of the 'non-red clover' fraction of the total herbage increased.A red-clover/grass sward may have advantages over a pure red-clover sward nutritionally, for silage-making and for its effect in diluting the oestrogenic activity of a pure clover sward. A major reappraisal of the role and potential of red-clover swards in the UK is warranted because of their many valuable attributes, particularly their ability to give high herbage yields of high nutritive value without the addition of fertilizer N. The improved persistency of some of the tetraploid varieties of red clover enhances the value of the plant.

Recombinant protein production plays a crucial role in the drug discovery process, contributing to several key stages of the pathway. These include exploratory research, target validation, high-throughput screening (HTS), selectivity screens, and structural biology studies. Therefore the quick and rapid production of high-quality recombinant proteins is a critical component of the successful development of therapeutic small molecule inhibitors. This chapter will therefore attempt to provide an overview of some of the current "best-in-class" cloning, expression, and purification strategies currently available that enhance protein production capabilities and enable greater throughput. As such the chapter should also enable a reader with limited understanding of the high-throughput protein production (HTPP) process with the necessary information to set up and equip a laboratory for multiparallel protein production.

Several experiments have been carried out on the winter production and utihzation of cocksfoot and other grasses (1, 2, 3). These have demonstrated the advantages of providing a crop which can be consumed in situ by outwintered animals. The trial described here was initiated to assess the suitability of cocksfoot for this purpose under the climatic conditions prevailing in the West of Scotland.The long northern winter makes the need for lessening the cost of feed very great and conserved grazing is ofthe utmost value. The preservation ofthe grass must not, on the other hand, take too much toll of the already short summer grazing. Thus the shortness of the summer season adds to the problems involved in this method of management, but greatly increases the value of such grass as can be economically conserved. EXPERIMENTAL METHODThe site chosen was a cocksfoot/white-clover ley sown in 1952 under a barley-cover crop. The seed mixture was 8 lb. S.143 cocksfoot, 8 lb. S.26 cocksfoot, and 2 Ib. S.IOO white clover. A uniform area of the field was selected for a factorial experiment of 48 x 0.005 acre plots, comprising four blocks of 12 treatment combinations. The treatments were as follows : DATE OF APPUCATION X DATE OF SAMPLING X NITHOGEN LEVEL