Vitamins and Minerals
Pages 260 - 265
• Why add them?
– Provide balance
– Bring up to
requirements
– Add value
– Shelf life
• How are they added?
– Pre weighed for a
particular inclusion
level
– Specialized
companies that
formulate and mix premixes
Minerals
• Minerals are inorganic compounds (Ash)
• Concentration in plant based feedstuffs
– Mineral content of the soil (varies by region)
– Mineral content of the water
– Mineral content of the fertilizer used
• Concentration in an animal's body varies and reflects
– Species
– Age
– Diet
Selenium
United States Geochemical Survey (USGS)
Mineral Resources
Animal Composition
Calcium = 1.29%
Phosphorus = 1.46%
Ca:P = 0.88
Calcium = 2.01%
Phosphorus = 1.52%
Ca:P = 1.19
MINERAL SUPPLEMENTS
• Classifications: macrominerals (major) or microminerals (trace).
– Macrominerals
• Greater than 100 ppm in an animal's body
• Usually fed in grams/day or %
• Na, Cl, Ca, P, Mg and sometimes K and S
– Microminerals
• Less than 100 ppm in an animal’s body
• Usually fed in the ug/d or mg/d range (ppm, mg/kg, ug/g)
• Cu, Fe, I, Mn, Se, Zn and Co
• Adequate concentrations and balance between minerals are very
important.
– Excessive amounts of one mineral may interfere with utilization of
one or more other minerals.
Minerals: More is not better!
• Minerals interact with one
another
• Even if no interaction occurs,
minerals may be outright toxic
• Maximal levels are of some
concern
in many situations
• Federal and State laws often
require maximum specifications
listed on labels
Figure 8.1 Mineral interactions.
Performance
Mineral Intake vs. Performance
OPTIMAL
Severe
Deficiency
Subclinical
Deficiency
Subclinical
Toxicity
Severe
Toxicity
Bioavailable Trace Mineral Intake
MINERAL SUPPLEMENTS
• Specialized companies formulate
• Most diets are formulated by computer
programs designed to minimize cost
– This can lead to problems with pre-mixes.
– Often nutritionists responsible for formulating
mineral supplements will specify which
mineral sources are to be used and not allow
the software to select minerals based on
price.
– Pre-mixes need to be formulated based on
need in the diet not cost.
Mineral Considerations
• Chemical form
• Affects biological availability
• Carbonates, chlorides, oxides, sulfates, chelates, etc.
• Physical form
• Especially fineness
• Influences how well it mixes with other ingredients
• Absence of harmful impurities
• Requirements
• Fast growing animals (swine, poultry) have greater mineral
requirements to support bone growth/health
MINERAL SUPPLEMENTS
Figure 8.2 Examples of common mineral supplements.
MINERAL SUPPLEMENTS
Salt (NaCl)
•
•
•
•
Common salt, practically pure sodium chloride
Most common mineral supplement
Often used in diets to regulate feed intake
Palatable – animals typically consume enough
to meet requirements
– Not a problem, given adequate supplies of water
• Used as a carrier for other elements or
materials a feeder wants animals to consume
– Medications (anti-parasitic, anti-bloating, etc…)
MINERAL SUPPLEMENTS
Salt (NaCl)
• Necessary for water balance in the body; therefore,
specifically required for production.
– Requirements increase as fluid losses increase, as when
sweating or when milk production increases.
• Ruminants & horses: 0.5 to 1% salt
• Poultry & pigs: 0.25 to 0.5% salt
• When salt is mixed in feed, it should be fairly
fine in texture, non-caking, and free flowing.
– Salt is often fed ad libitum to ruminants & horses, as their
requirements are higher than swine or poultry.
• Feeding methods and strategies allow this practice.
Salt (NaCl)
• Salt may be fed in loose form or as compressed blocks.
– Blocks tend to restrict intake compared with loose salt
– Convenient to use
– More weather resistant than loose salt
– Advances in technology
Salt (NaCl)
• Toxicity concerns
– Swine & poultry are much more susceptible
– Water restriction increases risk
– High salinity water or soil may reduce need to
supplementation
• Iodized salt
– supply a minimum of 0.007% iodine.
• Trace-mineralized salt is commercially
available
– Co, Cu, Fe, I, Mn, & Zn.
Calcium and Phosphorus
• Most animal diets require supplementation
– Skeletal growth, lactation, egg production, muscle
contraction.
• Many feedstuffs are borderline to deficient in
Ca & P or they are not in proper balance (1:1
to 2:1)
– Phosphorus can be an issue for high forage fed
herbivores.
– Calcium can be an issue for high cereal grain fed
herbivores.
– Improper balance: urinary calculi
• Ca Deficiency: milk fever
Calcium and Phosphorus
• Most non-plant Ca sources are well utilized by most
animal species
– Although net digestibility may be low, there is little difference
between Ca sources
• Not the case for P
• The usual recommendation is to consider only half of
plant P available for non-ruminant species (phytates)
– Ruminants utilize phytin P due to production of phytase, which
releases P from the phytin complex.
– Methods to increase biological digestibility of P in non-ruminants
has resulted in commercial availability of phytase products.
Calcium and Phosphorus
• Marked differences also exist in the biological
availability of some inorganic P sources.
– Phosphoric acid and the mono-, di-, and
tricalcium phosphates are well utilized.
– Curacao Island and colloidal (soft) phosphates
are utilized less well by most animals.
• Some sources from rock phosphates must be
defluorinated.
– Otherwise, long-term consumption may produce
chronic fluorine toxicity.
Calcium and Phosphorus
• Dicalcium phosphate is one of the more common supplements for
both Ca and P.
– Processed bones (steamed bone meal, bone ash, etc.)
– Chemically treated bones
– Adding Ca to phosphoric acid: Di-Ca-P precipitates
• Additional Ca & P sources include monocalcium and tricalcium
phosphates.
• Salts such as calcium oxide
• Calcium sulfate (gypsum) is sometimes added
to ruminant rations containing non-protein N to provide needed S.
• Calcium carbonate (limestone) – useful when you don’t want more
phosphorus in the diet.
• Calcium acetate binds P
• Calcium citrate can acidify urine
• Anionic salts (magnesium sulfate, calcium chloride) make ration
more acidic increasing Ca absorption (implication for milk fever)
Magnesium
– Function
• Electrolyte
• Major cation cofactor for enzymatic reactions including
transfer of P from ATP – ADP – AMP (over 300 rxns)
– Mg oxide is most common supplemental form.
• 52 – 56% Mg
– Magnesium carbonate or sulfate are also used
• Sulfate has a laxative effect, more expensive
– Dolomite limestone contains about 12% Mg
– Deficiency: grass tetany
• Fertilize with N or K = worse
Potassium
• Potassium
– Function
• acid-base balance and electrical and chemical gradients (interacts with
Cl and Na) and nerve function
– Deficiency
• Typically not an issue in animal diets and often not needed in
supplemental form (except lactating dairy cattle or other ruminants fed
high concentrate diets)
– Not palatable at high levels so voluntary intake will decrease
– Forms: chloride, bicarbonate, carbonate, acetate, citrate, sulfate,
phosphate, iodide, and gluconate
– Higher requirement for ruminants on high-concentrate diets,
lactating, water losses, heat stress
•
•
•
•
Poultry – 1,500 – 5,000 mg/kg
Swine – 1,500 – 3,000 mg/kg
Feedlot cattle – 5 – 7,000 mg/kg
Dairy cattle - 10,000 mg/kg
Sulfur
• Sulfur
– Widely distributed in nature (gypsum, epsom salts)
– Many forms: calcium sulfate, magnesium sulfate,
sulfur containing AA’s
– Function: sulfur containing compounds (Methionine,
cysteine, taurine, thiamin, chondroitin, glutathione)
– Deficiency not common if protein is adequate
– Toxicity
• Principal species of concern: Ruminants
(Polioencephalomalacia)
• Reacts and forms complexes with other minerals – reducing
availability
Microminerals (Trace Minerals)
• Microminerals most commonly added to animal
diets include:
– Cobalt; Copper; Iodine; Iron; Manganese; Selenium; Zinc.
• Iron (Fe)
– Component of hemoglobin and myoglobin, transports oxygen
– Considerable iron oxide (rust) is used as a coloring agent in
things such as trace-mineralized salt
– Other forms: iron carbonate and ferrous sulfate
– Deficiency common in piglets – Fe injection at birth
Microminerals (Trace Minerals)
• Copper (Cu)
– is most commonly added as the sulfate
– Oxide, carbonate & hydroxide are used sometimes
– Component of many enzymes, hemoglobin synthesis,
hair pigmentation
– Most deficiencies are due to other mineral
antagonists (molybdenum, sulfur and iron)
• Sheep are extremely sensitive
– 10 mg/kg Cu if diet is high in molybdenum and Fe, is tolerated.
If Mb and Fe are low, that level will be toxic
Trace Minerals
• Manganese (Mn) is usually required in poultry diets (high
in corn)
– Deficiencies on normal diets: cattle, swine, poultry –
resulting in bone abnormalities and poor metabolism
– Interacts with Ca, P, Fe
– Oxide and sulfate are most often used in feeds
– Considered one of the least toxic minerals
• Cobalt (Co) is required only by rumen microorganisms.
– To synthesize vitamin B12
– Most often added as the carbonate or sulfate.
Trace Minerals
• Iodine
– required for synthesis of thyroid hormones to control metabolism
– is a very reactive mineral most often fed as iodized salt, but also fed
in various other forms (kelp, seaweed – pet diets)
– Problematic in all meat diets (pets)
• Zinc
– is required biochemically in zinc-finger protein domains
(DNA/RNA), protein synthesis
– frequently needed in most animal diets commonly supplied as Zinc
oxide/sulfate.
• Selenium is required for at least 12 enzymes
– Can be very toxic
– Deficiency more common in conjunction with Vitamin E (White
muscle disease in ruminants; liver necrosis in other species)
Trace Minerals
• For trace minerals added to premixes, regulations
require the minimum amount to be specified.
– Selenium (Se) is the only trace mineral closely
regulated in the United States by the FDA.
• Feeding of chelated minerals (“organic minerals”)
has been promoted to prevent formation of
insoluble complexes in the GI tract & reduce
amount of a particular mineral required in the diet.
– Chelates are compounds with the mineral atom bound
to an organic complex. (amino acid, carbohydrate, etc.)
– Chelated minerals are commonly used in rations.
Mineral Marketing and Propaganda
• Bioavailability
– Measure of use of mineral to support a physiological
function
• Little information on how much of the minerals in
feeds are truly bioavailable
– Will not be 100%
– Difficult to study – need to use radioactive isotopes
– Significant biological recycling of minerals in the body
– Variation among species utilization
PROBLEMS WITH COMMERCIAL
MINERAL SOURCES
• Feedstuff variability
• Generalized commercial mineral supplements may
not be as accurate as they should be
– May not meet specific need/deficiency
• Livestock feeders must be careful to reasonably
ensure mineral needs of their animals are met
– Cost of mineral is small in comparison to benefits
– Pay particular attention to needs of operation
VITAMIN SOURCES
• Almost all feedstuffs contain some vitamins,
but concentrations in plant or animal tissues
varies tremendously.
– Plant vitamin variation affected by:
• Harvesting, processing, and storage conditions, as well
as by plant species and plant part.
– Animal vitamin variation affected by:
• Age, portion of the body used (liver and kidney are
generally good sources of most of the vitamins).
– Yeasts and other microorganisms are also
excellent sources, particularly of the B vitamins.
VITAMIN SOURCES
• As a rule, vitamins are not stable
– easily destroyed by heat, sunlight, oxidizing
conditions, or mold growth.
• If question of dietary adequacy arises, it is
better to err on the high side than risk a
deficiency.
• Difficult and very expensive to analyze in
diets (HPLC)
Optimum Vitamin Nutrition and
influencing factors
McDowell, 2004
Vitamin Considerations
• Vitamins likely to be limiting in natural diets:
– A, D, E, riboflavin, pantothenic acid, niacin,
choline, and cobalamin (B12)
– Biotin may also be a problem in swine, poultry,
horses, pets (plays a role in hoof/skin health).
– Thiamin + vitamin E are major concerns for
managed piscivorous species
– Vitamin K may be needed because some feed
additives may inhibit adequate
synthesis
– Niacin may aid fat metabolism &
ketosis prevention
Vitamin Supplementation
• Monogastrics
– Corn-soy diet generally adequate in E, thiamin, B6, and
biotin
– Pigs and poultry -supplement Vit A, D, E, K, niacin,
riboflavin, pantothenic acid, B12
– Layers need higher A, D, E vs. broilers
• Ruminants
– Vit C, D synthesized, and rumen bacteria make B vitamins
– Generally supplement Vit A,E, sometimes D
– Pre-ruminant calves would need B vitamins
• Start making B vitamins as early as 8 days of age
– Concentration of vitamins in colostrum is greater than in
milk
Fat-Soluble Vitamins - A
• Best feed sources of carotenes (provitamin A)
are green and yellow plants.
– Commercially, dehydrated alfalfa leaf and alfalfa
meals or sun-cured alfalfa are typical sources.
– Concentrated sources, such as carrot oil or alfalfa
extracts, are also used.
– Dry products in which carotene has been
absorbed on a millfeed product
– Carotene products in vegetable or animal oils
– Cats cannot meet Vitamin A requirement through
carotenoids
Fat-Soluble Vitamins - A
• Vitamin A, itself, is not found in plants, but only
in animal tissues.
– The liver & liver oils and kidneys from fish are good
sources (cod liver oil)
• Though still used commercially, fish liver oils have
been largely replaced by synthetically produced
vitamin A, due to cost differences.
– For feeds, vitamin A is normally sold in a dry, gelatincoated form to which antioxidants have been added.
– The common chemical form is the ester, usually as
vitamin A acetate, propionate, or palmitate.
Vitamin A
Stirs controversy
• Retinyl palmitate – ester of vitamin A
combined with the saturated fatty acid
palmitic acid from palm oil
• Marketing concerns for feed
and pre-mix manufacturers
due to conservation and
environmental concerns
– Roundtable on Sustainable
Palm Oil (RSPO)
Fat-Soluble Vitamins - A
• Vitamin A preparations normally are quite stable
and can be added to most feed mixes or liquid
supplements without much loss of vitamin
activity during normal storage periods.
• Grinding a feed makes it susceptible to vitamin
loss due to heat involved, and because ground
feed is more exposed to oxygen.
– It is now a common practice to add antioxidants
to premixes to minimize vitamin destruction.
– Supplemental sources are protected by coating them
with emulsifying agents, antioxidants, gelatin & sugar.
VITAMIN SOURCES
Fat-Soluble Vitamins - A
• Other factors that may reduce vitamin A
content:
– Time in storage, temperature, exposure to
ultraviolet light, and trace mineral content of
the diet.
– Moisture or hygroscopic compounds such as
choline chloride or urea.
VITAMIN SOURCES
Fat-Soluble Vitamins - D
• Feedstuff sources: sun-cured forages, fish liver
oils, and synthetic vitamin D produced by
irradiating yeast, plant, or animal sterols with
ultraviolet light.
– Most commercial feeds have vitamin D added.
• Four-footed animals are able to convert vitamin D2
to D3, but poultry utilize D2 very inefficiently.
– For poultry, vitamin D is standardized in International
Chick Units (preparations containing crystalline D3).
– Use of D3 in feeds for animals other than poultry is
more efficient, resulting in lower dietary requirements.
VITAMIN SOURCES
Fat-Soluble Vitamins - D
• Vitamin D3 is found naturally in animal products,
but vitamin D produced from irradiation of plant or
yeast products is in the D2 form.
– D-activated animal sterol is available dissolved in oil
or absorbed by flour or other fine powders.
– Vitamin D2 supplements & irradiated are available.
• Vitamin D is relatively stable in mixed feed
– Rapid losses can occur when mixed directly with
limestone, oxidizing compounds & and some organic
ingredients.
VITAMIN SOURCES
Fat-Soluble Vitamins - E
• Vitamin E (primarily a-tocopherol) is present
in most common feedstuffs, but found in
highest concentrations in the germ or germ
oil of plants.
– Moderate concentrations in green plants or hays
or in dehydrated alfalfa meal.
– Synthetically produced concentrates are
available.
• Vitamin E is an antioxidant; thus, it is lost
rapidly in any situation resulting in oxidizing
conditions.
– Heat, light, high trace mineral content of feed,
etc.
VITAMIN SOURCES
Fat-Soluble Vitamins - K
• Vitamin K is widely distributed in green plant
material & produced by microbes in the GI tract.
• Important in blood-clotting cascade
• Many compounds have vitamin K activity, but
menadione, a naturally occurring compound,
is usually the normal reference standard.
– It is fat soluble, stored in relatively high
concentrations in animal tissues or in seeds such as
soybeans.
– Two common water-soluble forms, menadione
sodium bisulfite and menadione dimethylpyrimidinol
bisulfite, are often used as feed supplements.
VITAMIN SOURCES
Water-Soluble Vitamins
• Animal & fish by-products, green forages, yeast,
fermentation products, milk by-products, oilseed
meals, and some seed parts are usually good
sources of the water-soluble vitamins.
– Cereal grain bran layers are fair to moderate sources.
– Roots and tubers are poor to fair sources.
• Cobalamin (B12) is the only required vitamin that is
not found in plants.
– It is produced exclusively by microorganisms, so
good sources are yeast or similar products.
– Animal manures also contain B12.
VITAMIN SOURCES
Water-Soluble Vitamins
• Water-soluble vitamins produced
synthetically may be used when especially
high vitamin content is needed in some
particular situation.
– Thiamin hydrochloride; Riboflavin; Nicotinic
acid or nicotinamide.
– Pyridoxine; Choline chloride; Ascorbic &
Pantothenic acid.
Examine Your Mineral Tag