Making $ense of Mineral Supplementation

1
Making ense of Mineral Supplementation

• Cody Wright, PhD
• Extension Beef Specialist
• South Dakota State University

2
Introduction

• Animals require numerous minerals (macro and
  trace) for maintenance, growth, and reproduction
• Mineral nutrition is complex and not well
  understood

3
Assessing Mineral Status

• Objectively analyze production
• Rule out other factors
• Determine mineral supply
• Forage, supplement, and water
• SAMPLE, SAMPLE, SAMPLE!!
• Directly sample the animal
• Blood or liver

4
Sampling Feeds

• Trace minerals in clipped and selected samples
  are similar
• Selected samples generally contain greater levels
  of Ca and P than clipped samples
• Sample the forages that cattle are grazing

5
Sampling Feeds

• Sample silages or delivered feeds periodically to
  monitor changes
• Minerals in feeds and forages are not 100
  available
• 50 is a reasonable guideline
• Dont forget the water

6
Assessing Mineral Status

• Compare mineral supply to requirements
• Consider intake
• Feed and mineral

7
Requirements

• Depend on
• Age
• Size
• Sex
• Physiological state
• Level of performance
• Breed
• Presence of antagonists

8
Antagonists

• Sulfur
• gt 500 ppm in water can ? Cu absorption
• Alone or in combination with Mo
• Molybdenum
• CuMo ratio of 4.51 and dietary S gt .25
• Iron
• gt 50 ppm

9
Meeting Requirements

• Primary sources of minerals
• Forage (grazed or harvested)
• Supplemental feed ingredients
• Supplemental minerals
• Fed
• Bolus
• Injected

10
Western Wheatgrass
Mineral Live Dead
------------------ of DM ------------------ ------------------ of DM ------------------
Ca .25 .22
P .16 .07
Mg .12 .07
K 1.6 .3
Adapted from Grings et al. (1996) Mineral
concentrations in live and dead tissue differ P lt
.01
11
Western Wheatgrass
Mineral Live Dead
--------------------- ppm --------------------- --------------------- ppm ---------------------
Zn 20 15
Cu 2 2
Mn 47 49
Mo 1 1
Adapted from Grings et al. (1996) Mineral
concentrations in live and dead tissue differ P lt
.01
12
Sandhills Meadow Hay
Mineral Cherry Rock Holt
Cu (ppm) 9.4 6.7 6.5
Zn (ppm) 26.1 25.5 27.5
Mn (ppm) 85.9 111.9 131.5
P () .25 .29 .15
Mg () .17 .19 .16
K () 1.1 1.6 1.3
Adapted from Hickock et al. (1996) 75 of
requirement for gestating cow
13
Formulating Supplements

• Considerations
• Animal requirements
• Minerals in feeds and forages
• Potential antagonists
• Sources and levels
• Expected responses

14
Formulating Supplements

• Phosphorus is generally the most expensive
  mineral to supplement
• So, why do we feed so much?

15
Phosphorus

• Late 1930s
• King Ranch
• ? calf crop by 40 and 41
• ? weaning wt by 69 lb and 49 lb
• ? lb weaned per cow exposed by 156 lb and 165 lb
• Return per 1 invested 3.95 and 12.35

Adapted from Herd (1997)
16
Phosphorus

• Karn (1995 and 1997)
• Less dramatic responses
• Heifers - ? conception rates and weight gain
• Cows - ? weight gain and weaning weights
• Small and inconsistent

17
Formulating Supplements

• General guideline
• Each 1 P costs adds 11 per ton
• Reducing from 12 to 8 P
• ? mineral cost by 44 per ton
• Savings of 1.50 per cow
• 750 per year for a 500 hd operation

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Supplemental P
Body weight, lb Total diet P, Total diet P, Total diet P,
Body weight, lb .05 .15 .25
------ P needed in supplement ------ ------ P needed in supplement ------ ------ P needed in supplement ------
1000 8 6 6
1100 10 6 6
1200 10 6 6
1300 12 6 6
1400 12 6 6
Adapted from Paisley and Hill (2000)
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Supplemental P
Stage of production Total diet P, Total diet P, Total diet P,
Stage of production .05 .15 .25
------ P needed in supplement ------ ------ P needed in supplement ------ ------ P needed in supplement ------
Late gestation 16 6 6
Lactation
10 lb/d 16 6 6
20 lb/d 16 10 6
30 lb/d 16 12 6
Adapted from Paisley and Hill (2000)
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Phosphorus in Feeds
Feed P in feed lb fed per day lb fed per day lb fed per day
Feed P in feed 2 4 6
------- P added to diet ------- ------- P added to diet ------- ------- P added to diet -------
CGF .95 .07 .14 .21
DDG .83 .06 .12 .19
SFM 1.02 .08 .15 .23
WM 1.00 .08 .15 .23
Gestating cows require .17 to .22 Lactating cows
require .22 to .39
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Formulating Supplements
Mineral of NRC requirement of NRC requirement of NRC requirement
Mineral 75 100 125
Cobalt 9.6 12.8 16
Copper 960 1280 1600
Iodine 48 64 80
Manganese 384 5120 6400
Selenium 9.6 12.8 16
Zinc 2880 3840 4800
Assumes 1200 lb cow consuming DM at 2 of body
weight and mineral intake of 3 oz per day
22
Maximum Levels

• Selenium
• 3 mg/hd/d or .3 ppm in diet
• Iodine
• 10 mg/hd/d
• Well below level claimed to prevent footrot

23
Mineral Sources

• Critical to formulating cost-effective programs
• Cost per unit of mineral
• Consider mineral concentration and bioavailability

24
Bioavailability

• Most bioavailable
• Organic
• Sulfate and chloride
• Carbonates
• Oxides
• Least bioavailable
• IN GENERAL, BUT NOT ALWAYS!!

25
Organic Minerals?

• Two supplements
• 100 of NRC _at_ 3 oz per day
• 100 inorganic 580/ton
• 50/50 blend 680/ton
• 17.2 ? in cost (3.42 per cow)

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Responses

• Key to evaluating changes
• Potential benefits
• Health
• Weaning weight
• Growth performance
• Reproductive efficiency

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Responses
? Immune Function
? Growth or Fertility
Clinical Signs
Sub-Clinical
Clinical
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Responses

• Cost / benefit analysis
• Must be able to pay for any increase in cost
• Can we reduce cost without sacrificing production?

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Strategic Supplementation

• Supplement only when needed
• Begin 45 days before calving
• Continue through breeding season

30
Strategic Supplementation

• Year round
• 400 per ton _at_ 2 oz per day
• 9.13 per cow
• Strategic (Feb 1 to July 1)
• 400 per ton _at_ 3 oz per day
• 5.63 per cow (38 less)
• 1750 savings on 500 hd operation

31
Summary

• Objectively evaluate current herd mineral status
• Rule out other factors
• Sample forages, supplements, and water to
  determine mineral intake and level of antagonists

32
Summary

• Formulate or purchase mineral supplements to
  correct imbalances
• Develop strategic mineral program to reduce
  expenses
• Estimate and objectively evaluate production
  responses