Chapter 21: Nutritional Contributions of Minerals to Humans and Animals

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Chapter 21: Nutritional Contributions
of Minerals to Humans and Animals
• Chapter overview:
– Chapter 21 presents the impacts of minerals on
animal health:
• identification and major sources of minerals
• functions of minerals
• impacts of mineral deficiencies
General Comments:
• There appears to be little difference in
requirements for the minerals between
species
• Requirements can be significantly impacted
by other organic or inorganic components of
the diet
– Example: phytin binds phosphorus and
increases zinc requirement
General Comments:
• Minerals are abundant in many natural
feedstuffs, but
• Supplementation of feeds and foods with
common inorganic major sources of
minerals is typical
The Minerals:
• Minerals are generally categorized as:
– Macrominerals: those required in larger
amounts, such as Ca, P, Mg, Na, Cl, K, S
• example: calcium requirement may be 0.5% in some
diets
– Microminerals: those required in very small
amounts, such as Fe, Cu, I, Co, Zn, Mn, Se,
Mo, F
• example: Zn requirement may be 50mg/kg (0.005%)
in some diets
The Macrominerals:
Calcium (Ca):
• Functions - bone and tooth formation,
blood clotting, muscle contraction
• Deficiency symptoms - rickets, slow
growth, osteomalacia, tetany, thin-shelled
eggs
• Major sources - milk, legumes, bone meal,
dicalcium phosphate, limestone
Phosphorus (P):
• Functions - bone and tooth formation; part
of DNA, RNA, and many enzyme systems
• Deficiency symptoms - rough hair coat,
pica, slow growth
• Major sources - milk, eggs, oilseeds, cereal
grains, bone meal, dicalcium phosphate
Magnesium (Mg):
• Functions - enzyme activator, component of
skeletal tissue
• Deficiency symptoms - anorexia,
hyperirritability, muscular twitching and
tetany, profuse salivation
• Major sources - abundant in feeds,
especially green, leafy vegetables and grains
Sodium (Na):
• Functions - muscle contraction,
maintenance of osmotic pressure of body
fluids
• Deficiency symptoms - loss of appetite and
weight, salt craving, soil eating,
• Major sources - common salt added to
supplements or in free-choice blocks
Chlorine (Cl):
• Functions - maintenance of osmotic
pressure of body fluids, acid-base activity,
production of HCl in stomach
• Deficiency symptoms - craving for salt,
reduced appetite
• Major sources - common salt added to
supplements or in free-choice block form
Potassium (K):
• Functions - maintenance of electrolyte
balance, enzyme activator, muscle function
• Deficiency symptoms - heart lesions,
weight loss, reduced appetite, muscle
weakness, poor wool growth
• Major sources - widely distributed
throughout feeds and foods
Sulfur (S):
• Functions - component of sulfur-containing
amino acids
• Deficiency symptoms - slow growth, poor
feed efficiency, slow wool growth in sheep
• Major sources - oilseed meals, forages,
cereal grains
The Microminerals:
Iron (Fe):
• Functions - carrier of oxygen as a
component of hemoglobin and myoglobin,
component of many enzyme systems
• Deficiency symptoms - anemia, diarrhea,
loss of appetite
• Major sources - eggs, forages and grains,
soil (example: rooting by pigs in soil)
Copper (Cu):
• Functions - erythropoiesis, component of
coenzyme system, hair pigmentation,
collagen and elastin synthesis
• Deficiency symptoms - depraved appetite,
stunted growth, diarrhea, bleached hair and
wool, ataxic gait, anemia
• Major sources - common in normal grains
and forages
Iodine (I):
• Functions - component of thyroxine
• Deficiency symptoms - goiter, hairless pigs
and woolless lambs at birth, poor
performance
• Major sources - added to almost all salt
sources (“iodized salt”), cod-liver oil
Cobalt (Co):
• Functions - component of vitamin B12, red
blood cell formation, rumen microorganism
function
• Deficiency symptoms - loss of appetite and
emaciation, weakness, rough hair coat,
anemia
• Major sources - inorganic cobalt
supplementation in the diet
Zinc (Zn):
• Functions - enzyme activator and
component
• Deficiency symptoms - poor growth,
feathering, and hatchability; anorexia;
parakeratosis
• Major sources - widely distributed in
feeds, with forages being major sources
Manganese (Mn):
• Functions - growth, bone formation,
enzyme activator
• Deficiency symptoms - lowered egg shell
strength and hatchability, perosis in poultry,
lameness and stiffness
• Major sources - widely distributed in
cereal grains, oilseeds, and legumes
Selenium (Se):
• Functions - related to vitamin E function,
destroys peroxides (antioxidant)
• Deficiency symptoms - necrosis of liver,
white muscle disease in ruminants
• Major sources - oilseeds and grains
• Note - excess is quite toxic
Molybdenum (Mo):
• Functions - component of enzyme systems
• Deficiency symptoms - deficiency
relatively unknown
• Major sources - widely distributed in feeds
and foods
• Note - deficiency of Mo accentuates Cu
toxicity, excess Mo reduces Cu absorption
Fluorine (Fl):
• Functions - tooth enamel formation,
prevention of tooth decay in humans
• Deficiency symptoms - poor enamel
formation
• Major sources - fluoride added to water
• Note - narrow range of “requirement”;
excess causes tooth enamel abnormalities
Other mineral considerations:
• Although only produced under
laboratory conditions, deficiency
symptoms can be created for:
–
–
–
–
Vanadium
Arsenic
Nickel
Tin
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