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Summary Publications in the National Research Council's series on This edition updates the requirements of sheep based on nutrient requirements of domestic animals support proper recent research and a need to consider higher levels of pro- animal feeding practices for the production of meat, milk, ductivity by larger and improved genotypes. It also repre- and fiber, and give advice on feeding animals that provide sents a major revision of the first edition of the goat re- companionship and recreation to world societies. Require- quirements, which was prepared from the scant research ments for energy, protein, minerals, vitamins, and water are data available at that time. During the last 25 years, volumi- defined, based on scientific evidence published in peer- nous research results on goat nutrition, especially on energy reviewed technical sources. Feeding standards, developed and protein, have accumulated. Similar to those considered from nutrient requirements of the animals and nutrient com- in the first edition of the goat publication, data used in esti- position of feedstuffs, provide readers with the knowledge mating requirements of cervids and New World camelids are and means to adopt proper feeding practices. Periodic up- limited, but estimates derived from those data and extrapo- dating of these publications is needed as new research infor- lated from data from similar species are presented as the mation accumulates and new needs surface. current standards. This report combines revisions of The Nutrient Require- The audience for this report is varied, as evidenced by the ments of Sheep (1985) and The Nutrient Requirements of nature of the many sponsors. The U.S. Department of Agri- Goats (1981), with considerations of other small ruminants culture (USDA) Multistate Research Committee concerned and ruminant-like species addressed for the first time. Inclu- with efficiency of sheep production issued a resolution stat- sion of the new species (e.g., cervids) required an expanded ing the urgent need to revise the existing nutrient require- view of products to include antlers and aesthetic value. The ment publications for sheep and goats. Sponsors that were sheep series began publication in 1945, and it was revised pe- forthcoming included the USDA Cooperative State Re- riodically until the sixth edition in 1985. The first edition of the search, Education, and Extension Service (USDA-CSREES; goat series, published in 1981, remains the most recent. Im- www.csrees.usda.gov) and the Joe Skeen Institute for plicit in the charge given to the committee (Appendix A) was Rangeland Restoration (http://www.animalrangeextension. that other small ruminants and ruminant-like species be iden- montana.edu/joe_skeen/contact.htm; Montana State Univer- tified and included if justified by anatomical, physiological, sity, New Mexico State University, and Texas A&M behavioral, and/or socioeconomic similarities. The species University System); American Sheep Industry Association listed below were identified for inclusion in this publication. (www.sheepusa.org); National Sheep Industry Improvement Center (www.nsiic.org); the Montana Sheep Institute Sheep (Ovis aries) (www.sheepinstitute.montana.edu/index.htm), and general Goats (Capra hircus) support of the Animal Nutrition Series provided by the Cervids Department of Health and Human Services (U.S. Food and White-tailed deer (Odocoileus virginianus) Drug Administration; www.fda.gov/cvm/). These agencies Red deer (Cervus elaphus) and organizations are interested in the current and potential Wapiti/American elk (Cervus elaphus) socioeconomic roles of small ruminants and in the impact of Caribou/reindeer (Rangifer tarandus) small ruminants (both domestic and wild) on sustaining envi- New World Camelids ronmental quality. Appreciation for this diverse audience Llamas (Lama glama) guided the structure of this report to address multilayers of Alpacas (Vicugna pacos) users from biologists, ecologists, and environmental scien- 1
2 NUTRIENT REQUIREMENTS OF SMALL RUMINANTS tists to practical nutritionists and flock or herd managers. Chapter 10 describes the physical and chemical nature of Some portions of the report will be too technical for readers plants in respect to the content and availability of required with less advanced training, while some readers may con- nutrients. The practical aspects of evaluating feedstuffs and sider other sections too elementary. Attempts were made to plant communities as sources of nutrients for small rumi- ease these difficulties by providing topical chapters for nants and designing management strategies are topics of selective reading. Chapter 11. Chapter 12 discusses the various possibilities of The publication begins with a brief introduction in Chap- negative environmental impacts of small ruminants and how ter 1. Then, Chapter 2 describes commonalities among the these can be avoided. Also, opportunities for positive influ- animal species in anatomical and physiological characteris- ences on the environment, mainly through the suppression tics, as well as some subtle differences. Similarities and dif- of noxious weeds by selective grazing, are discussed. ferences in size, shape, and location of the components of Chapter 13 identifies nutrition-related diseases and defi- the gastrointestinal tracts of the animal species are consid- ciency symptoms and describes strategies for prevention and ered. This explanation aids the reader in understanding the treatment. Some maladies are recognized problems among sites, rates, and partitioning that occur during the ingestion all species, whereas others are considered unique or more and processing of food as it flows through the digestive common to one or more species. tract. Terms relating to nutrients are defined and illustrated A guide for the practical use of this publication is pro- so the reader is not confused by too many abbreviations. Ni- vided in Chapter 14, and this chapter is recommended as trogen recycling is also described in this chapter. Finally, primary reading for some users. Although other chapters are Chapter 2 summarizes the roles of minerals and vitamins as cited, all essential information is provided for determining body components and in the various metabolic pathways. the needs for the different nutrients and for using the re- Small ruminants are important in their association with quirements tables in formulating diets or supplements. vegetation, both in their reliance for diet and in their impact The final section of the publication contains requirements on renewable resources. Chapter 3 addresses the feeding tables for sheep, goats, cervids, and New World camelids behavior of small ruminants, including differences in diet and composition tables for both common and novel feed- selection and intake and how they are affected by the char- stuffs. Regrettably, some nutrients were not available for acteristics and availabilities of various diet sources. some of the ingredients listed. Assistance in interpreting and Chapters 4, 5, 7, 8, and 9 provide discussions on require- using these tables is included in Chapter 14. ments for energy, protein, minerals, vitamins, and water, re- This publication was a challenge to prepare because it ad- spectively. The methods and equations used in calculating or dressed multiple species for a diverse audience. Although estimating requirements are described in detail, and perti- conciseness was an ever-present goal, completeness was nent references to data used are cited. Except in a few in- never sacrificed. The sheep portions update the 1985 edition stances when data were unavailable, the factorial method for in that a greater range in body size, litter size, and milk pro- calculating requirements was used. That is, separate esti- duction were considered. The quality and accuracy in the mates for requirements for the different physiological goat considerations greatly exceed those contained in the processes, including maintenance, pregnancy, lactation, first edition because of the large amount of research efforts body weight gain, and fiber production, are given. These invested since that document was published in 1981. How- separate estimates are used to construct the requirements ever, many requirement issues in minerals and vitamins have tables presented at the end of the publication, but are avail- not been resolved for goats. Rather, requirements were esti- able to the reader to customize requirements to fit unique mated from values derived in sheep and cattle studies. Con- circumstances. In some cases, requirements are estimated siderable data are available for cervids, but estimates for re- using data from other species of animals. This occurs most quirements for nutrients are somewhat sketchy and variable. frequently when requirements for various minerals and vita- Similarly for New World camelids, some data are available, mins for cervids and New World camelids are extrapolated but many have not been validated by multiple independent from sheep, goat, or cattle data. Less frequently, goat re- studies. To produce adequately complete requirements ta- quirements are calculated from sheep or cattle data. bles for cervids and camelids, it was necessary to extrapo- Lipids and essential fatty acids are covered in Chapter 6. late from data generated from experiments with similar Although some fatty acids are metabolically essential, sel- species. After enhanced efforts to generate definitive infor- dom are they of concern in small ruminants. However, di- mation in mineral and vitamin requirements for goats and all etary lipids for animals providing sources for human food nutrients for camelids, the next edition of the Nutrient Re- are topics of discussion and scientific study as they may re- quirements of Small Ruminants will be much more com- late to human nutrition and health. This chapter gives a thor- plete. However, the discussions, expressions, and values ough overview of the state of knowledge of lipids in small presented in this current edition are considered valid to the ruminant diets. level of present knowledge.