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 pre-mixes

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

SeleniumUnited 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.

Figure 8.1 Mineral interactions.

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 concernin many situations

• Federal and State laws often require maximum specifications listed on labels

Mineral Intake vs. Performance

Bioavailable Trace Mineral Intake

Perf

orm

ance

OPTIMAL

SubclinicalToxicity

SubclinicalDeficiency

SevereToxicity

SevereDeficiency

Bioavailable Trace Mineral Intake

Perf

orm

ance

OPTIMAL

SubclinicalToxicity

SubclinicalDeficiency

SevereToxicity

SevereDeficiency

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 fairlyfine 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 addedto 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 COMMERCIALMINERAL 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, gelatin-coated

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 feedand pre-mix manufacturersdue 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 vitaminactivity 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