Tropical animal feeding

A manual for research workers


T.R. Preston
University of Agriculture and Forestry
Ho Chi Minh City
Viet Nam

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ISBN 92-5-103758-2

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1. Managing natural resources for sustainable livestock-based agriculture

2. Identifying priority areas for research on tropical feed resources

3. Nutrition of non-ruminants

4. Feed resources for non-ruminants

5. Nutrition of ruminants

6. Feed resources for ruminants

7. Technologies for improving the use of renewable natural resources

8. Design and analysis of experiments

9. Biological and chemical analytical methods

10. Animal feeding trials

11. On-farm research: a discussion of some practical examples and procedures

12. Guidelines for the evaluation of feed resources

13. Presentation of research results



This is the second edition of the manual written by Dr. T.R. Preston and published by FAO in 1986, as Animal Production and Health Paper No 50/2: “Better utilization of crop residues and by-products in animal feeding: research guidelines. 2.: A practical manual for research workers” FAO, Rome, 154 pages. This manual has proven to be a very useful tool for research workers in developing countries and has been in great demand since its publication. After 9 years, it was necessary to update it taking into account the large experience gained in the meantime and the changes which have occurred during this period of time in the developing countries.

In fact, this manual has been completely rewritten and greatly extended. The new version contains twice the number of pages compared to the first one. Its scope is no longer limited to crop residues and by-products, but considers also other feeds. More attention has also been given to monogastric animals, because “modern” feeding systems imported from developed countries have in many countries led to the import of feeds, thus increasing the external debt of developing countries. Imports of feed by developing countries represent several billion dollars a year! The multipurpose role of livestock as a provider of food, but also of income, energy, fertilizer and its implications on feeding systems are considered. Environmental issues linked to livestock production systems are also taken into account. In this context, research constitutes a big challenge for animal nutrition scientists in developing countries: to promote feeding sustainable systems which make greater and better use of local resources for the benefit of small farmers.

The manual is not a list of recipes for making laboratory analyses or preparing experiments. Half of its contents is devoted to describing the essential principles which should assist the research worker in conducting useful and cost effective research. This includes: the importance of managing natural resources for sustainable development and of identifying priority areas for research aimed at solving practical problems and improving the lot of small farmers in developing countries, the basic principles of animal nutrition, the identification of important feed resources and of some appropriate technologies to better use them.

The contribution of various scientists who have accepted to review the first draft and made valuable comments and suggestions is acknowledged. Special mention is due to: M. Chenost and his colleagues (National Agricultural Institute, France), F. Dolberg (University of Aarhus, Denmark), B. Gohl (FAO Regional Project, Bostwana), N.M. Jayasuryia (IAEA, Vienna), C. Kayouli (National Institute of Agronomy, Tunisia), R.A. Leng (University of Armidale, NSW, Australia), E.R. Ørskov and his colleagues (Rowett Research Institute, U.K.), Rena Perez (Ministry of Sugar Production, Cuba), R. Sansoucy and his colleagues of the Feed Resources Group (FAO, Rome), A.W. Speedy (Oxford University, U.K.) and M. Wanapat (Khon Kaen University, Thailand).

The final editing of this publication was undertaken by Andrew Speedy, Department of Plant Sciences, University of Oxford, England, and Rene Sansoucy, FAO, Rome, and formatting by A.W. Speedy.