Minerals in Animal and Human Nutrition

639 Pages·2003·13.615 MB·English

by  L.R. McDowell

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Firstedition 2003
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This book isdedicated, with appreciation, to my parents; my wife, Lorraine; my
daughters, Suzannah, Joanna, and Teresa and their husbands and children; and
to three great animal nutritionists (Raymond B. Becker, Tony J. Cunha and
Jack K. Loosli) at the University of Florida for their practical knowledge of the
livestock industry and for encouragement to write books.
v
Preface
The second edition of Minerals in Animal and Human Nutrition contains under
one cover 19chapters of concise, up-to-date information on mineral nutrition for
livestockand poultry, with comparative aspects to laboratory animals and human
nutrition. Thefirstchapterisan introductiondealingwith historical considerations,
distribution in the body, general functions, mineral requirements and tolerances,
methods of analysis, mineral bioavailability, status detection, and incidence of
mineral deficienciesand toxicities.Chapters2through 14discussthe propertiesand
distribution, metabolism, functions, requirements, natural sources, deficiency,
supplementation, and toxicity of the established and most common minerals.
Chapter 15isconcerned with five toxic elements and their significance to various
speciesand methods of control. In Chapter 16,chromium and newly discovered
essentialand other traceelementsare discussed.Chapter 17coversmineral sources,
whileChapter 18deals with maximum tolerance levels.The final chapter discusses
mineral supplementation concepts.
The present second edition has been completely and vigorously revised. Since
the first edition in 1992, a great deal of newinformation has been generated in the
field of minerals; this is reflected by the fact that more than half of all the
referencesin the majority of chapters have been published since the first edition.
The newedition continues to provide a large number of classic photographs that
illustrate mineral deficiencies and toxicities that have been provided by
distinguished scientists in the mineral research field. The purpose of this book
is to provide, as both a collegetextbook and a reference source, a comprehensive
text that contains current information on mineral nutrition. Most emphasis is
centered on minerals in which naturally occurring deficiencies or excessesare of
economic importance. A unique feature of this book is the practical implications
of mineral deficienciesand excessesand the conditions under which they might
occur in various animal speciesand humans.
It is hoped that this book will be of worldwide use and will continue, as the
first edition, to be used as a textbook and as an authoritative reference book for
use by research and extension specialists, in the animal, poultry, and veterinary
sciences fields and for feed manufacturers, teachers, students, and others.
A comparison between the balance of chemical, metabolic, and functional
aspects of minerals and their practical and applied considerations has been made.
Unlike other textbooks, this one places strong emphasis on practical aspects of
mineral supplementation in each chapter and devotes the last chapter to this
subject.
When preparing the two editions of this book, I obtained numerous suggestions
from eminent scientists in both the United States and other countries. I wish to
express my sincere appreciation to them and to those who supplied photographs
and other material used. I am especially grateful to C. B. Ammerman, J. D.
xv
xvi Preface
Arthington, R. B.Becker, D. K. Beede,G. D. Butcher, G. E. Combs,J. H. Conrad,
G. K. Davis, G. L. Ellis,P. Henry, J. F. Hentges, W. E. Kunkle, J. K. Loosli, P. G.
Mallonee, R. M. Mason, R. D. Miles, R. O. Myer, W. M. Neal, E. A. Ott, A. L.
Shealy, R. L. Shirley, H. D. Wallace, A. C. Warnick, and S.N. Williams (Florida);
O. Balbuena and B. J. Carrillo (Argentina); B. Hetzel (Australia); E. Espinosa
(Bolivia); N. dos Santos Fernandez, Jiirgen Dobereiner, Francisco Megale, and C.
H. Tokarnia (Brazil); T. Ma (China); W. J. Miller and N. W. Neathery (Georgia);
M. Anke (Germany); U.S. Garrigus (Illinois); S. P. Arora (India); W. M. Beeson
(Indiana); D. V.Catron and V. C. Speer (Iowa); C.W. Absher, J. A. Boling, G. L.
Cromwell, V. W. Hays, and D. E. Miksch (Kentucky); J. O. Evans (Kenya); J.
Mtimuni (Malawi); G. F. Combs and W. Mertz (Maryland); C. Garcia Bojalil
(Mexico); A. T. Forrester, E. R. Miller, and D. E. Ullrey (Michigan); L. E.
Carpenter and H. S.Teague (Minnesota); B. O'Dell and R. L. Preston (Missouri);
J. Kubota, M. L. Scott, and S. E. Smith (New York); K. M. Hambidge and J. D.
Latshaw (Ohio); J. Adair, O. H. Muth, J. E. Oldfield, and F. M. Stout (Oregon); J.
Zorrilla-Rios (Panama); R. M. Leach (Pennsylvania); M. Echevarria (Peru); O. E.
Olson (South Dakota); B. D. H. Van Niekerk (South Africa); O. M. Mahmoud
(Sudan); H. S.Ergunand K. Goksoy(Turkey); A. E.OlsonandJ. L. Shupe(Utah);
J. C. Montero, D. Morillo, and E. A. Velasco (Venezuela); I. A. Dyer, J. W.
Kalkus, and R. C. Piper (Washington); G. Bohstedt and M. L. Sunde (Wisconsin);
and O. A. Beath (Wyoming).
I am particularly grateful to Nancy Wilkinson and Pamela Miles for working on
various sections and tables of the book and along with my wife (Lorraine
McDowell) for their thorough editing assistance and useful suggestions. I wish to
thank Mary Schemear, Shirley Levi, Patricia French and Sabrina Robinson for
skillful typing. Finally, I am indebted to the Animal Sciences Department of the
University of Florida for providing the opportunity and support for this
undertaking.
Lee Russell McDowell
xvi
Chapter 1
General Introduction
I. INTRODUCTION
All forms of living matter require inorganic elements, or minerals, for their
normal lifeprocesses. All animal tissues and all feeds contain inorganic or mineral
elements in widely varying amounts and proportions. Some confusion exists in use
of the terms "minerals" and "elements" in nutrition and feeding. In practical
nutrition, the term "mineral" is generally used to denote all the mineral inorganic
elements. However, not all the elements are minerals (i.e., carbon, hydrogen,
oxygen, and nitrogen), and minerals frequently found as salts (e.g., carbonates,
oxides and sulfates) can be a combination ofdifferent inorganic elements. For the
purpose of this book, the terms "mineral," "element," and "mineral element" are
used interchangeably.
The mineral elements are solid, crystalline, chemical elements, which cannot be
decomposed or synthesized by ordinary chemical reactions. These inorganic
elements constitute the ash that remains after ignition of organic matter. The
common method of determining the total mineral or inorganic content of feeds
consists merely of measuring the total ash remaining after high-temperature
burning ofthe organic matter. This analysis is oflittle value either for expressing
mineral requirements or for indicating the useful mineral content offoods, for two
basic reasons. In the first place, body requirementsare specificfor certaininorganic
elements. Secondly, ash may not be a measure of total inorganic matter present,
because some organic carbon may be bound as carbonate and some inorganic
elements, such as sulfur (S),selenium (Se),iodine(I), fluorine (F), and even sodium
(Na) and chlorine (Cl) may be lost during combustion. In practice, the most
important reason for the determination of total ash in a food is to permit
calculation of the nitrogen-free extract by difference, as required in the proximate
analysis offoodstuffs. Also, the ash analysis can be used in forages to estimate the
amount of dust and soil that has been harvested with the feed.
II. CLASSIFICATION OF MINERALS
Minerals are classified in a number of ways, with some classification schemes
having a place in understanding their requirements and/or nutritional roles.
Minerals that are needed in relatively large amounts are referred to as major or
1
2 GeneralIntroduction
TABLE 1.1
Essential Mineral Elements
Newer Microelements
Traditional Established Minerals (Discoveredsince 1970)
Macrominerals Aluminum (AI) Arsenic(As)
Calcium (Ca) Phosphorus(P) Boron (B) Bromine(Br)
Potassium (K) Magnesium (Mg) Fluorine(F) Germanium (Ge)
Sodium(Na) Chlorine(CI) Lead (Pb) Lithium (Li)
Sulfur (S) Nickel (Ni) Rubidium (Rb)
Silicon (Si) Tin (Sn)
Microelements (traceminerals) Vanadium(V)
Cobalt(Co) Copper(Cu)
Chromium (Cr) Iron (Fe)
Iodine(I) Manganese(Mn)
Molybdenum (Mo) Selenium (Se)
Zinc (Zn)
macrominerals. Others that are needed in very small amounts are referred to as
trace minerals or microminerals. These terms do not imply any lesser role for the
trace minerals. Rather, they represent quantity designations based on the amounts
required in the diet and their generally lowor "trace" concentrationsin tissues. The
major minerals are required in concentrations of greater than 100ppm (parts per
million) and often as a percentage of the diet (or gper kg), while trace elements are
required at less than 100 ppm and are expressed as ppm and sometimes as ppb
(parts per billion). Twenty-nineelements are known to be required by at least some
animalspecies(Table 1.1).Sevenelements are macromineralsand 22can be referred
to as microminerals or trace elements.
The listing of some of the trace elements as essential is difficult and sometimes
tentative. An essential element isone that is required to support adequate growth,
reproduction, and health throughout the life cycle, when all other nutrients are
optimal.
Essentiality islesscertainwhen there isonly asmall change in the rate of growth,
when the environment issuboptimal, or when there isa microbial infection (O'Dell
and Sunde, 1997).Observed improvements in performance upon supplementation
with a mineral may be due to changes in the intestinal microflora, to a
pharmacologic effect, or to interactions with other elements.
The proofthateach elementisessential rests upon experiments with one or more
species. In these experiments, clinical signs produced by diets adequate in all
nutrients, except the mineral in question, have been prevented or overcome by
adding that mineral to the diets. All the elements mentioned have not been tested
withallspecies,butitishighly probablethat there are fewexceptionsto the need for
allofthem byallhigher animals.Thereisnodisagreementconcerningtheessentiality
of the trace elements chromium (Cr), cobalt (Co), copper (Cu), I, iron (Fe),
manganese (Mn), molybdenum (Mo), selenium (Se),and zinc (Zn) although not all
would presentpractical nutritional supplementalproblems for livestock or humans.
Classification ofMinerals 3
Whether an element isconsidered essential would depend on the criteria used. A
viewpoint in human nutrition is that nutritional requirements should include
consideration of the total health effects of nutrients, not just their roles in
preventing deficiency pathology (Nielsen, 1996).Therefore, the terms "beneficial
element" and "apparent beneficial intake (ABI)" are in use. In humans, for
example, the ABI for maximal benefit ofF relates to its proven benefits for dental
health and its suggested role in maintaining bone integrity. The ABI seems more
appropriate for the elements with beneficial, if not essential, actions that can be
extrapolated from animals to humans; these elements include, in addition to F,
arsenic (As), lithium (Li), nickel (Ni), silicon (Si), and vanadium (V).
More recently discovered trace elements since 1970are referred to as "new trace
elements." These newer trace minerals are elements with an established or highly
suspected requirement for one or more species, and include aluminum (AI), As,
boron (B), bromine (Br), F, germanium (Ge), Li, Ni, lead (Pb), rubidium (Rb), Si,
tin (Sn), and V. The essentiality of these last 13elements is based on growth and
other effects with animals under highly specialized conditions, such as improved
proceduresfor purification ofdiets and useofmetal-freeisolatorsystemsfor raising
animals. Furthermore, more precise and accurate methods ofdetermining minute
quantities oftrace elements have been developed. Although markedly different in
their chemistry, mode of action, and effective levels, the newer essential trace
elementshave in common the facts that they were first known for their toxic effects
and that induction of a dietary deficiency is often difficult.
An additional 20 to 30trace elements occur regularly in feeds and animal tissue,
and it isunknown whether they serve some useful purpose or are merely incidental
contaminants. It is likely using advanced methodology that some ofthese elements
one day will be considered essential. It is also possible that some of the more
tentativelyestablishedessentialelements may bedeclared non-essential with further
studies.
Eight mineral elements can also be classified as cations, including calcium (Ca),
magnesium (Mg), potassium (K), Na, Fe, Mn, Cu, and Zn. Six other elements are
either anions or are usually found in anionic groupings. These are chloride (CI-),
iodine (1-), phosphate (PO~),molybdate(MoO;), selenite (SeO) and sulfate S04'.
Likewise, they can be classified on the basis ofvalence number and on their group
position in the periodic chart of the elements. These classifications can be useful
because they describe physical and chemical attributes ofimportance in nutrition
(Miller, 1979). For example, the monovalent cations, K and Na have a very high
absorption percentageand majorinterrelationshipsexist between them. In contrast,
the absorption percentage ofthe divalent cations (Ca, Mg and Zn) is much lower.
Numerous factors may alter the availability ofthe essential anions and cations.
The most soluble and absorbable form ofany ofthe elements should be the simple
ionic state of the atom or ionic group of atoms (for example, as Ca++, Mg++,
Mn++). However, many electronegative compounds in nature are looking for a
cation with which it can share its electrons, thereby forming a stable compound
(Leeson and Summers, 200I). Often the resultant compound is highly insoluble in
water but nevertheless dissociates to a sufficient extent in the intestinal tract to
4 General Introduction
allow absorption of the essential cations. This isinfluenced by the gastric acidity of
hydrochloric acid in the stomach, which converts the cations temporarily into
chloride salts, which allows good absorption from the intestinal tract. Therefore,
even Mn oxide, Cu sulfide, or Zn oxide, which are highly insoluble chemical
compounds, are converted to Mn chloride, Cu chloride, or Zn chloride which are
forms more easily absorbed.
III. mSTORY
The purpose of this section is to provide an overview of the historical
development of knowledge concerning the essential nature ofmineral elements as
related to deficiency and excess.Table 1.2summarized chronologically the history
of important events relating to the nutrition of mineral elements. Most research
accomplishments will not be cited in the Literature Review, and the reader should
consult additional reports (i.e., Maynard, 1937; McCollum, 1956; Underwood,
1966,1981;McCay, 1973;Loosli, 1978,1991;Georgievskii et al., 1981;McDowell,
1985; Underwood and Mertz, 1987) for a more comprehensive treatment of the
subject. Likewise,historical treatmentofthe various minerals iscovered inchapters
2through 16ofthis book. Mineral nutrition ofdomesticanimals wasconsidered to
be of limited importance as late as the early 1900s (Ammerman and Goodrich,
1983).Armsby (1880) had concluded in his book, Manual ofCattle Feeding, that
"In practice, in the feeding of mature animals intended to be kept in a medium
condition, or to befattened, a lack ofthe necessary mineral matters isscarcely ever
to be feared. They are, indeed, generally in excess. Only common salt is in certain
respects, an exception..."
The history ofdeficiencydiseases must date from antiquity. However, before the
middle of the 19th century, only the most nebulous ideas existed as to the nature,
origin, and functions of the mineral constituents of plant and animal tissues
(Underwood, 1981).In1874,Forsterobservedthat the mineralsinthe ash oftissues
are required to support animal life (McCollum, 1956). This observation helped
establish the dietary essentiality of mineral elements. It should be recognized that
only when methods weredevised to identify and measure mineral elements in body
tissues and feedsand to characterize responses to pure elements, was it possible to
replace supposition with facts about the essential nature of any nutrient. Much of
the earlier knowledge about nutrition resulted from systematic observations
stimulated by a need to solve critical health problems with people and their
domestic animals. Often, a newscientificdiscovery has proven to bea confirmation
of common beliefsofnative people and an explanation of why the beliefs are true
(Loosli, 1974).
Much information about mineral needs of animals gained by trial and error over
centuries was never recorded, and there is no way oflearning what was practiced
(Loosli, 1978). There is a view that the "fall of Thebes was hastened by heavy
livestock mortalities caused by unidentified agents when grazing apparently
luxuriant pastures" (Underwood, 1966).There is also the suggestion that part of
History 5
TABLE 1.2
History ofNutritional ImportanceofMineralElements
29BC The "FallofThebes" washastened byheavylivestockmortalitiescaused by
unidentifiedagents whilegrazing luxuriantpastures.
40-120AD Saltfedto domesticanimals during thetimeofPlutarch.
23-79AD Virgiland Plinyrecommended saltsformilkproduction.
1295 ClinicalsignsofSetoxicosiswereapparentlydescribedby Marco Polo as
affectinggrazing livestockinChina.
1669 Brand isolatedphosphorusfrom urine.
Before1680 Sydenham treated anemia withiron filings.
1747 Menghini found iron in blood.
1748 Gahn reported phosphoruspresent in bones.
1770 Scheelereported that bonescontaincalciumphosphate.
1784 Scheelereported sulfur inproteins.
1791 Fordyce showedthat canaries need"calcareousearth"supplemented tograin diets.
1811-1825 Work byCourtois, Coindet, and Boussingault ledto thediscoveryofiodine, the
effectivenessofiodineinburnt spongesand specificallythat iodinewasthe
onlycure forgoiter.
1823 Proust reported chlorine inthehydrochloric acidingastricjuice.
1842 Chossat found pigeonsrequired calcium for bonegrowth.
1847 Liebigreported potassium inanimal tissues.
1847 Boussingaultconductedthefirstexperiment that cattle needcommon salt.
1850-1854 Chatin publishedstudies relatingenvironmentaliodinedeficiencyto incidenceof
endemicgoiter inmanand animals.
1869 Raulin discoveredtheessentialityofzincforthemicroorganism Aspergillus niger.
1873 VonBungeput forward thehypothesis ofantagonismbetweensodium and
potassium and betweensodium and chlorine.
1880 Forsterdemonstrated that animals require minerals, and feedingdogsonly
meat resulted indeficiencies.
1893-1899 VonBungeand Abderhaldenshowedthatyounganimals receivingmilk
require supplemental iron.
1905 Babcockstudied salt requirements ofcattle, noting particularimportancefor
lactating cows.
1919 Kendall isolated and named thyroxin from thyroid gland; the hormone
wasfound tocontain 65%iodine.
1920 Bertrand inFrance and McHargue inthe United States initiated the useof
purifieddietsto study the needand function ofvarious minerals
1922 Bertrand and Berzonshowedzincwasnecessaryfor rat growth and hair development.
1922 McCollum and co-workers found that inaddition tocalcium and phosphorus,
ricketsiscaused byvitamin Ddeficiency.
1924 Theilerand co-workers illustrated phosphorusdeficiencyfor grazingcattle and
found that supplementationcorrected bonechewing,prevented death lossfrom
botulism. and increasedgrowth and reproductive rates
1926 Leroyshowedthat magnesiumincreasesthe growth ofmice.
1928-1933 Warburgestablishedthat respiratory enzymesinanimals containan iron porphyrin
group.
1931 Neal, Beckerand Shealyestablishedcopper asan essentialelement for ruminants.
1931-1933 Kemerer and McCollum showedmanganese wasessentialfor ratsand mice,a
deficiencycausing tetany. Sjollemarelated a lickingdiseaseincattle tocopper
deficiency.
(Continued)
6 General Introduction
TABLE 1.2 (Continued)
1935 Frankeand Potteridentifiedseleniumasthe factor inforage responsible for alkali
diseaseinfarm animals.
1935 Duncan and Huffman observedtetany incalvesdue to lowmagnesiumcontentofmilk.
1935 Underwood and Filmer and, independently, Marstonand Linesfound thatenzootic
marasmus insheepwasacobalt deficiency.
1936-1937 Wilgus,Norris and Houser reported that manganese deficiencyresultedin aperosis
inchicks.
1937 Beckerand co-workersestablished that the "saltsick" conditionofcattle inFlorida
(USA)wascaused bya combinationofpasturedeficienciesofcobalt, copper and iron.
Bennetsand Chapman demonstrated that enzootic ataxia ofnewborn lambs resulted
fromewesreceivinginsufficientcopper during pregnancy.
1938 Ferguson, Lewisand Watson showedthat molybdenum toxicityresulted inasevere
diarrhea for grazingcattle.
1938-1942 Hevesyand others beganto useradioisotopes to study mineral metabolism.
1940 Keilinand Mann reported zincasacomponentoftheenzymecarbonic anhydrase.
1946 Moultonestablished that smallconcentrationsoffluorine indrinkingwater prevented
dental caries.
1948 Rickesand co-workers and, independently, Smithshowed that Co isan integral part of
vitamin B12•
1950-1954 Dick noted metabolicinterrelationshipsamong copper, molybdenum and inorganic
sulfatesinruminants.
1953 Richert and Westerfieldisolated molybdenum from the metalloenzyme xanthine oxidase.
1954 Needyand Harbaughfound thathighfluorineconcentrationsindrinking water
resultedinmottling oftooth enamel.
1955 Tucker and Salmondiscoveredthat parakeratosis, a severeskin disease,wasazinc
deficiencyfor swine.
1957 Schwartzand Foltz identifiedseleniumasa factor that prevents livernecrosisinrats.
1958-1959 Scott preventedexudative diathesis inpoultrywithselenium,whileMuth, Oldfield,
Remmert, McLean, Thompson,Claxton and others prevented white-musclediseasein
ruminants withthiselement.
1959 Schwarzand Mertzshowedthat chromium wasessentialfor glucosemetabolism.
1970-1997 The most recentlydiscoveredelements("newtraceelements") wereestablished using
highlypurifieddietsand metal-freeisolatorsystems.Theseelementsincluded aluminum,
arsenic,boron, bromium, fluorine,germanium, lead, lithium, nickel,rubidium, silicon,
tin, and vanadium.
'Compiledfromanumberofsources,includingMaynard,1937;McCollum,1956;Underwood, 1966,1981;McCay,
1973;Loosli, 1978;Georgievskii etal.,1981;McDowell, 1985;Underwoodand Mertz, 1987.
thereason for the"fall ofRome" wasrelated to infertilitycaused byPb toxicosisof
the upper classdue to useof metal versus clay cooking utensils.
Common salt was an item of trade before recorded history to satisfy the salt
cravingsofgrazinganimals and for useto flavor foods. Wars wereevenfought and
children were sold into slavery to obtain the precious commodity, salt. Feeding
"salts" to domestic animals can betraced to the time ofPlutarch (40to 120A.D.).
Virgiland Pliny(23to 79A.D.) recommended salts for milk production. There are
many referencestothe feedingofsalt inBritain after 1750followingland enclosure.
Phosphorus wasisolated from urine in 1669by Brand, and both Ca and P were
shown to beconstituents ofbone byGahn in 1748. In 1842, Chossat demonstrated