by Lorin E. Harris and Leonard C. Kearl
The need for full information on animal feeds is well recognized. It may serve for agricultural planning or for trading purposes, but is of particular importance in ration formulation. The cost of feed is of great importance in the economics of animal production. The increasing scarcity of the world's food supply calls for greater precision in its use as feed for farm animals, but this presupposes that the productive value of feed as well as the nutritional requirements of animals is accurately and widely known. Such knowledge, obtainable only through research, needs to be converted through documentation into meaningful information that is accessible to all potential users.
There is therefore a great need for data collection to be closely linked to research and to be organized on an international level. This article is concerned with an attempt to establish through international cooperation a world data bank on the nutritive value and use of feedstuffs.
Lorin E. Harris is Professor of Animal Science and Director, International Feedstuffs Institute, Utah State University, Logan, Utah, where Leonard C. Kearl is Research Associate in Animal Science and Associate Director. This article is taken from their Report on Project 079, Journal series No. 1835.
In countries with a high standard of animal production the composition of feedstuffs and their nutritive value for animals of various kinds and levels of production are fairly well documented. Information is also available on alternative ways of using the materials in rations. However, improved facilities for rapid retrieval and for international exchange of such information would greatly enhance its value.
In most of the developing world there is not only a serious lack of statistics on available materials but also a major deficiency in essential basic data on chemical, physical and biological constants for feeds. Unfortunately, little of the information needed on the nutritional characteristics of a developing country's existing or potential feed supply can be derived from established feed data from the technically advanced countries. The problems faced by the animal nutritionist in developing countries (which represent, roughly, the tropical world) are very different indeed from those encountered in the more highly developed temperate zones. The demand situation for human food does not usually allow the feeding of products which are suitable for human consumption to animals. Forages and crop by-products from the agro-industrial sector therefore form the major source of feed. Not only do the different plant species account for a large part of the variation in chemical and physical plant properties, but the stage of maturity and the environmental effects of climate, soil and fertilization also influence these characteristics. High temperatures and intense solar radiation, for instance, have an accelerating influence on the lignification process, which in turn, is an important factor affecting digestibility.
Food technology for the preparation of human foods with by-products suitable for animal feeding is still very much at an unsophisticated level of development. Feed production continues to be integrated into the animal production sector, and work to be undertaken in animal nutrition has to be closely oriented to the conditions prevailing in a given region or even in a specific location. This, added to the profound information gap in developing countries, points to the urgent necessity for generating data through applied nutrition research, preferably on the spot. National and international development aid organizations have a responsibility to provide guidance in the planning and conduct of such work to ensure documentation of the information generated.
Ideally, systems applied in handling feed data should be compatible with the efficient exchange of such data between centres. Specialized information centres in some technically advanced countries have been working toward such compatibility and toward the creation of a common data base with the possibility of rapid, computerized retrieval. It seems sensible therefore to suggest that the data emerging from research in developing countries be added to the common data base and that in future due consideration be given to universal requirements in international standardization efforts at data processing.
Above: Conducting an in vivo digestibility and balance trial.
International network of feed information centres
The need for information on nutritional value of feeds over vast geographical areas was highlighted when FAO commenced work on the Indicative World Plan in the mid-1960s. This need was therefore followed up by FAO's Statistical Advisory Committee of Experts, but attempts to collect data using questionnaires proved unsuccessful. It thus came to be realized that the problems of data accumulation from the developing countries could not be solved by assembling material supplied on request, but that technical advice on generating data, followed by coordinated systematic collection and uniform processing, was required. In 1971 FAO appointed a consultant to review on-going international activities in the fields of feed data collection and retrieval and to report on possibilities for international collaboration. The report considered the value of a collaborative effort in this field both to developing countries and to animal production at the international level and recommended that FAO act as coordinator for international activities in this field.
A first consultation meeting was held in 1971 in Rome. At that time representatives from several feed information services formed the International Network of Feed Information Centres (INFIC). Members (besides FAO) were: the Australian Animal Feedstuffs Collating Centre, Canberra; the Canadian Department of Agriculture, Ottawa; the Documentation Centre at the University of Stuttgart-Hohenheim, Federal Republic of Germany; the International Feedstuffs Institute of the Utah State University; and the USAID Feed Composition Project, Florida. Since then this group has met once a year and has been joined by representatives from the International Livestock Centre for Africa (ILCA). Addis Ababa: l'Institut d'elevage et de médécine vétérinaire des pays tropicaux (IEMVT), Maisons-Alfort, France: and the Tropical Products Institute (TPI). London, United Kingdom. The USAID Feed Composition Project in Florida has meanwhile been terminated and its remaining activities transferred to the Utah Centre. Participation by other feed information services continues to be welcomed by INFIC: thus, it is considered desirable to have a Latin American Centre cooperating with Utah. The regular annual meetings of the group have been concerned with policy matters and with planning and development of the international network.
The aim of INFIC is to combine, by use of the computer, world data on the composition and nutritive value of materials which are or may be used as feeds and to provide linked abstracts of and references to other information about feeds. This necessitates interconversion of existing data stocks and adoption of standardized methods of data collection and processing. For the establishment of such a common data base, work toward a number of subordinate goals has been identified.
Determining in vitro digestibilities of feedstuffs.
I. Geographical coverage
This requires that different centres be responsible for the acquisition and processing of data from different regions of the world. At present only the centres at Hohenheim and Utah are able to undertake computerized handling. However, the Institutes in Canberra and Maisons-Alfort plan to reach this stage shortly. It is therefore planned that, for the time being, data collected by institutions without computer facilities will be sent to one of the two fully equipped centres. The complete correlation of master tapes will, however, be undertaken by a single centre only; at present this is Utah. The distribution of geographic responsibility is as follows:
Punching data from the source forms into cards. The data are transferred from these cards into the computer, and stored on disks or tapes.
Published feed data and information are collected from world literature.
II. Advice on feed evaluation methods
A body such as INFIC, which encourages the production of feed data and undertakes their collection, has a responsibility to advise analysts on the most suitable and useful analytical determinations. There is a particular need to recommend economical determinations that most accurately reflect the energy value of feeds. International agreement on the use of energy systems for expressing energy values is also urgently needed. The results of discussions between leading analysts and workers in energy metabolism and other related fields will therefore be put into effect.
III. Data recording
The direct transfer of data to an electronic computer system requires a unified method for the recording of laboratory analytical data as well as of published information.
Agreement has therefore been reached within INFIC for establishing an international recording system. The code numbers used on the international source form — which was developed by Harris (1963), and which already has wide distribution — are to be retained in any future recording system. An enlarged recording system has already been proposed by Hohenheim and a data input sheet in French, based on the Utah source form, is under preparation at Maisons-Alfort. For the incorporation of literature and summary abstracts (which are available in certain centres) it is planned to insert into the abstracts an International Abstract Number and an International Feed Reference Number.
IV. Vocabulary and principles for describing feeds
In recording data from different parts of the world and processing them for use in a common data bank, a standardized unambiguous identification system for feedstuffs is essential. This must include (a) a vocabulary consisting of elements (descriptors) that do not overlap, and (b) regulations for the use of these descriptors in naming feeds. Based on the principles of the International feed nomenclature (Harris et al., 1968a) developed at the Utah Centre in cooperation with Canada and used in Australia, Latin America and North America, a new vocabulary in English, French and German was recently proposed by the Hohenheim Centre. After review by a specialized committee, this has been adopted by INFIC. The vocabulary is divided into logical categories (or facets) as explained below. A feed name is established by combining descriptors of different facets, and a translation by computer is possible— for example, from English into French names. The terms used in the vocabulary might not always correspond to those in common use in a given country. In these instances adjustments will have to be made for conversion of international documentation terms into common terms.
V. Agreement on coding and computer programming
To achieve exchange by computer of data in the data banks at Hohenheim and Utah, in addition to nomenclature, prior agreement is also necessary on information code numbers, feed classes, data structure and appropriate computer programmes. Work is in progress for the establishment of an International Data Processing System, by integrating the best parts of both systems at present in use at Utah and Hohenheim.
The authors (left, L.C. Kearl, right, L.E. Harris) demonstrate least-cost ration formulation, using a remote terminal connected by telephone to the central computer at Utah State University. The operator types in the costs of the feeds, and the codes which inform the computer of animal nutrient requirements. The central computer calculates the animal diet, and the portable terminal prints out the one it will be most profitable to use.
Documentation methods employed
There is variation in the extent to which the individual INFIC centres are involved in literature documentation, that is, in the indexing of publications and preparation of abstracts from selected information. An internationally standardized form suitable for computerized handling of such abstracts is in preparation. With regard to documentation of values from feed analyses, different methods have been applied in the acquisition of data as well as in the subsequent steps of processing. Howèver, the work toward integration of the two systems used at Utah and Hohenheim will lead to a unification of methodology. Some important steps in handling the input are outlined below.
Data come primarily from two sources: (a) they are requested from cooperating feed analysis laboratories on distributed recording sheets (international source forms mentioned under III above); or (b) they are extracted from a wide range of published and unpublished documents and are also recorded on the source forms.
All analyses on any given feed sample are entered on the same form, which is designed to gather all necessary details on the sample. The main categories of information are: laboratory address, description of the sample, experimental conditions, analytical data, including procedure reference.
Data are checked for usefulness and, if necessary, converted into standardized units or into the preferred basis. In the future a statistical analysis procedure is to be applied for deciding on extreme values.
Identification of feeds
As mentioned under IV above, a feed is named by combining elements of various facets. These are:
Feeds have been assigned to eight classes. Further subdivision of up to nine groups each is envisaged. The eight main classes are:
Since the descriptive feed names are not quite practicable for data processing, a consecutive order 5-digit identification number (International Feed Reference number) is assigned to each name. The code for the feed class is inserted in front of this reference number (which would be a 1-digit number, making a 6-digit number in all — see table below).
Two examples of naming are given in the table. Thus the International Names for the two feeds are:
No. 1: Zea mays indentata, maize, aerial part, ensiled, dough stage (3).
No. 2: Gossypium spp., cotton, seeds w some hulls w lint, solv extd grnd, mn 36 percent protein (5).
All feed names are listed in the International Name File. Any new name not previously composed is added to this file.
Codes are assigned to all data on the source form, before they are put on punch cards. From the cards data are then transferred to a magnetic tape for sorting by data type, checking for coding errors and possible elimination of data. A number of computer programmes are available for further data processing.
|Name components||Feed. No. 1||Feed. No. 2|
|Genus (of original material)||Zea||Gossypium|
|Variety or kind||indentata||...|
|Part eaten||aerial part||seeds w some hulls w lint|
|Process(es) and treatment(s) (to which product has been subjected)||ensiled||solv extd grnd|
|Stage of maturity||dough stage||...|
|Cutting or crop||...||...|
|Grade (or quality designation)||...||mn 36 percent protein|
|International Feed Reference No.||3-02-912||5-01-632|
Benefits from the work of INFIC may be obtained by the results of international standardization of feed data documentation, and in the main from the output facilities of the common data base. The information stored in the combined data bank of INFIC will be of particular value to those involved in, for instance, research and education, planning and development, the feed industry and practical animal production. Eventually the total output is aimed at providing ready access to:
Information retrieval may be accomplished in various ways depending on the user's needs and the facilities he has for receiving the information. Retrieval would be largely in the form of feed tables and print-outs when use of computer data and information tapes, direct or via a remote terminal, is impracticable for a user. Feed composition tables may be of the conventional form: by animal species and type of production, and by type of data (e.g., minerals, amino acids and so on). It is envisaged that in future there will be more frequent withdrawals in response to specific inquiries. The system is ideal for providing information such as the value of feeds from one crop species, from a group of crops or from the crops of a given area. Additionally, abstracts of information relevant to specific questions can be selectively withdrawn.
The system also permits analysis of factors affecting composition and nutritional value of feeds (e.g., environment and technology of processing), provided the sample analysed has been sufficiently described (for example, as requested on the International Source Form distributed to the cooperating laboratories).
Data may also be suitable for the establishment of regression equations. The importance of giving consideration to the experimental conditions under which data were obtained and of distinguishing between actually determined and derived values is well recognized. Especially important is the efficient use that can be made of the international data store by connecting with it linear programming operations for the formulation of least cost rations.
Cooperation required to support INFIC's objectives
It is obvious that the potential output from a data bank depends both in quantity and quality on its input. The provision of information across fields of specialization, countries and languages requires close cooperation between institutions all over the world. Certainly, there are a number of limitations to achieving the aim of an optimal coverage in the documentation of world data. Particular assistance is sought by INFIC from:
Representatives from the participating countries have expressed interest in the work of INFIC and pledged continued support for it. The United States Agency for International Development (USAID) has made an essential contribution through its Florida project, during which 69 laboratories in 23 Latin American countries have cooperated in producing, collecting and forwarding analysis results to the Project Centre. Comprehensive feed composition tables have been published in Spanish, Portuguese and English. Assistance by USAID is being continued for the participation of the Utah Centre in INFIC. The Government of the Federal Republic of Germany is supporting work toward INFIC's objectives undertaken by the Hohenheim Centre in cooperation with FAO and ILCA.
The aim of INFIC is to combine (by the use of the computer) world data on the composition and nutritive value of materials which are or may be used as feeds, and to provide linked abstracts of, and reference to, other information about feeds. As an essential prerequisite for the successful exchange between existing data stores and for organizing future input to a common data base agreement is being established on a multilingual feed nomenclature, on information coding, data structure and computer programming. Efforts are being made to encourage standardized data production in, and coordinated collection from, areas that are at present least well covered.
The output of the common data base may take many forms depending on the needs of users which can range from conventional feed composition tables to replies to specific inquiries. The output of the system is also immediately applicable in linear programming operations for the formulation of least cost rations.
INFIC can provide a unique service to advisers in developing countries; it also incorporates services of proven value for the technically advanced countries.
To become fully successful in its work INFIC requires the collaboration of all laboratories that produce or hold information on feeds, particularly in developing countries, and continued support from funding agencies.
Alderman, G. 1971. Proposals for the establishment of a feeds information system for the Food and Agriculture Organization. Rome, FAO. FAO-AGA/MISC/71/28.
Association of American Feed Control Officials. 1974. Official publication. Baton Rouge, Louisiana. 184 p.
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McDowell, Lee R., Conrad, Joe H., Thomas, Jenny E. & Harris, Lorin E. 1974b. Latin American tables of feed composition. Gainesville, Fla., Department of Animal Sciences, University of Florida. 448 p.
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