Feedstuff evaluation

Feedstuff evaluation

86 cattle also has valuable information on the high protein content in the liveweight gains of Continental bulls, and the consequences for diet formu...

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cattle also has valuable information on the high protein content in the liveweight gains of Continental bulls, and the consequences for diet formulation. This book is highly recommended as a standard reference work that should be on every Agriculture Department's library shelves, whether College or University, and is also worth purchasing by professional ruminant nutritionists who operate overseas and are willing to take the time to study it carefully. G. ALDERMAN

Department of Agriculture, University of Reading, Reading RG6 2AT, UK

FEEDSTUFF EVALUATUON

FeedstuffEvaluation. Proceedings of the 50th Easter School in Agricultural Sciences, University of Nottingham. J. Wiseman and D.J.A. Cole (Editors). Butterworth, London, 1990. 456 pp., 25 papers, many tables and figures, £ 70.00, ISBN 0-408-049715. Over a decade has now passed since several new systems for the evaluation of the energy and protein requirements of ruminants were published (INRA, 1978; ARC, 1980; NKJ, 1985 ), and then implemented in a number of European countries. Such new systems generate demands for methods of measuring the nutritive value of feeds in the new units for energy and protein, which practising animal nutritionists need in their daily work. Much useful applied research on these parameters has now been published in specialist scientific journals. A review of these requirement systems in practice, the need for further progress, and the development work in analytical methods needed for their successful use, is therefore very timely. All this useful information is assembled here in one publication, and critically reviewed by competent authorities. The organisers of this Easter School have maintained their record for assembling international contributors of eminence in their particular field, making this publication one of the best it has been the reviewer's pleasure to read. There are some notable omissions from their list of authors, such as Van Es, who led this field of work in Europe throughout the 1970's, Sauvant of INRA, whose work on the chemical composition of raw materials and compound feeds deserves a wider audience, and there is no contribution from a German scientist. Feedstuff evaluation is not a glamorous research field in which to work, although calorimetry in the 1970's was the big science of its day. The principles of calorimetry for pigs and ruminants are described in a chapter by Close, and this is accompanied by one by McNab on Apparent and True ME measurements on poultry feeds. The opening chapter by Van der Honing and Steg is a masterly and detailed review of European energy systems for ruminants, well matched with one by Van Straalen and Tamminga on Protein Degrada-

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tion. The latter chapter includes tables of degradability values for numerous ruminant feeds in use in the manufacture of c o m p o u n d feeds. Since the fitted a, b and c parameters are also quoted, the data can be used to calculate degradability values for different outflow rates from the rumen from those tabulated. Oldham and Emmans contribute a closely argued critique of present feed evaluation systems, pointing out their weaknesses, the direction in which developments must go, and those currently taking place. The importance of the palatability and voluntary intake of feeds is not forgotten, as one of the key parameters that must accompany feeding standards. There follow several chapters on the chemical evaluation of polysaccharides, fats, minerals and vitamins in animal feeds, to match the protein evaluation chapter. To the practising animal nutritionist, the next four chapters are invaluable, since they deal with the prediction of the energy content of pig, poultry and ruminant feeds using in vitro or chemical analyses alone. The need for an EEC method for energy assessment of c o m p o u n d feeds for legislative purposes provided a much needed stimulus here, and valuable work has been published during the 1980's on these topics. Again, the work is reviewed by acknowledged experts in this field, although Carr6 and Batterham omit some work of importance in their reviews. The review of pasture evaluation by Thomas and Chamberlain completes this set of chapters admirably. Developments in chemical analysis are not overlooked, with a paper by Baker on Near Infra Red Reflectance methods of forage evaluation, as presently used by the U K Advisory Services. His colleagues Bailey and Henderson contribute a chapter on inter-laboratory variation, a much ignored subject of vital importance when results are compared between laboratories, or legal consequences ensue from their use. Accurate laboratory work is the foundation on which Tables of Feed Composition should be assembled, and Dutch and U K workers have collaborated to give a useful chapter on this problem. The volume concludes with contributions on toxic factors, residues, mycotoxins and animal pathogens which can be found in raw materials or manufactured feeds. As with other publications in this series, all papers are very fully referenced, giving the reader quick entry into the highly specialised literature of Feed Evaluation. Proofreading has not been quite up to standard in some chapters, but that apart, this volume is warmly recommended as a necessary standard reference for practising European animal nutritionists, and teachers of animal production courses. G. ALDERMAN

Department of Agriculture, University of Reading, Reading RG6 2AT, UK