RUMINANT NUTRITION

Andy Macdonald and Chris Kneale

with thanks also to Colin Morgan

SAC Animal Nutritionist

1

Ruminant Nutrition

Aims:

• To understand the basic processes and terms used in ruminant nutrition

• To be able assess feed quality from feed labels and feed analysis

• To understand the basic principles of rationing for beef and sheep

• To be understand how to alter feeding to manipulate finishing periods and timing

2

Workshop Topics

• 1. Basic Principles of Ruminant Nutrition

• 2. Assessing Feed Quality

• 3. Feeding Suckler Cows

• 4. Feeding Ewes

• 5. Feeding Lambs

• 6. Feeding Beef Cattle

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1. BASIC PRINCIPLES OF RUMINANT NUTRITION

4

RUMINANT DIGESTIVE TRACT

5

RUMEN - MICROBIAL DIGESTION (Volac/KW Alternative Feeds)

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ENERGY SOURCE FOR MICROBES AND HOST

• Host animal provides microbes with ideal continuous fermentation conditions – nutrients, water, waste removal

• Microbes ferment fibre, starch etc to produce energy, building blocks for new cells and by-products are volatile fatty acids, carbon dioxide and methane

• VFA absorbed by host and used to supply energy or for fat or glucose synthesis

7

Dry Matter – why is it important? • Know what you are feeding, and how much you

need to feed

• Most breakdowns of feed quality (energy, protein etc) measured in terms of dry matter

• All animals’ feed intake capacity relates back to dry matter

• Dry matter content will also affect feed intakes, especially fresh and preserved forage

8

METABOLISABLE ENERGY (M.E.)

• ME – essential information for rationing!

• Energy in food (released when it is burnt)

minus energy in faeces

minus energy in urine

minus energy in methane

• Used with varying efficiencies according to use (maintenance, growth, milk)

• To supply energy that the animal actually uses

• Units Megajoules MJ/kgDM (1 MJ = 240 calories= 1 Twix!)

• D Value %: digestible organic matter in the dry matter

9

TYPICAL METABOLISABLE ENERGY VALUES OF FEEDS (MJ/kgDM)

Barley 13.2 Hay 8.5

Wheat 13.6 Silage 10.5

Oats 12.0 Straw 6.5

Rapeseed meal 12.0 Draff 11.1

Soyabean meal 13.8 Pot ale syrup 14.2

Molasses 12.7

Malt dist grains 12.2

Wheat dist grains 13.5 Ewe nuts 12.5

Beans 13.3 Dairy cakes 12.5-13.5

Peas 13.5 Beef nuts 12-13

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DIGESTION OF PROTEIN – RUMINANTS (MLC)

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METABOLISABLE PROTEIN SYSTEM TERMS 1

• Effective Rumen Degradable Protein (ERDP)

- protein captured by rumen bugs

• Fermentable Metabolisable Energy (FME) for bugs

=ME - ME from fat – ME from ferm. acids

• Undegradable Dietary Protein (UDP)

- protein which escapes rumen degradation and passes into small intestine for digestion

12

METABOLISABLE PROTEIN SYSTEM TERMS 2

• Digestible Undegradable Dietary Protein (DUP)

• Metabolisable Protein (MP)

- total protein absorbed from the small intestine to meet animal’s requirements and

= Digestible Microbial Protein + DUP

Protein type • Some feeds more degradable than others - urea 100%; RapeseedM 75%; SoyabeanM 65%

13

ERDP REQUIREMENT

• Requirement for rumen microbial growth

• Calculated as g ERDP/MJ FME

• Deficiency results in

– insufficient supply for rumen microbes

– reduced microbial activity

– reduced digestibility and intake

– reduced performance

SO IS ESSENTIAL IN ALL DIETS

Extreme deficiency , very low protein diets, straw

- little or no rumen microbial activity and can cause death due to rumen impaction

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PROTEIN COMPOSITION OF RUMINANT FEEDS

Feed FME ERDP DUP ERDP DUP

MJ/kg g/kgDM g/kgDM

DM r = 0.05 r = 0.08

(Intensive diet)

Silage 7.6 97 15 94 18

Hay 8.0 44 23 39 28

Barley 12.7 105 14 99 19

Rapeseed meal 10.8 288 57 265 78

Soya bean meal 12.7 376 123 323 171

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METABOLISABLE PROTEIN REQUIREMENTS

• Microbial protein usually supplies enough MP

• But if MP from microbes not sufficient then need to supply more as DUP

because MP = digestible Bug protein + DUP

• DUP required in diets for animals producing high protein output

• high yielding dairy cows

• rapidly growing young animals

• ewes in late pregnancy and lactation

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2. ASSESSING FEED QUALITY FROM ANALYSIS AND LABELS

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Silage Analysis

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Silage Analysis – What to Look For

• Dry Matter (DM) – can vary widely depending on time of cutting, wilting, age of grass, weather, etc. Target usually 25-35%

• M.E. – very important, can also vary widely 7-12 MJ/Kg DM

• Protein – important, and again can be variable. 103g/Kg DM = 10.3%

• D value – digestibility, range from 45 - 78

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Silage Analysis – What to Look For

• pH, VFA, Lactic Acid – measure of fermentation. VFA indicates poor fermentation and risk of spoiling in pit

• NDF – amount of fibre – high indicates older/later cut grass, likely to be lower D value

• PAL – potential acid load – risk of acid load in rumen

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Silage Analysis

• Scottish Pit Silages (2008)

Average Range

DM g/kg 286 164-530

ME MJ/kgDM 10.4 7.4-12.2

CP g/kgDM 111 74-156

• Big Bale Silages (2008)

DM 342 165 - 811

ME 9.9 5.9 - 12.0

CP 111 48 - 169

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Feed Labels – What to Look For

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Feed Labels – Know What to Look For

• Why are you buying the feed - energy or protein?

• Protein usually stated in freshweight e.g. HiPro Soya – 50% fresh = 56% dry

• ME rarely stated on label - be careful!

• Label ingredients ordered by decreasing inclusion rate. Used to be highest to lowest, now in range of %

• Oatfeed, palm kernel expeller, shea nut, etc – lower energy and palatability- often used as cheap “filler”, but may contribute to protein

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Feed Labels – Know What to Look For

• Be aware of urea as an ingredient and contribution to “protein” content – not true protein

• High fibre and ash contents can indicate lower digestibility, cheaper feeds – depends on end use as well – may be appropriate for situation

• Watch label allowances–4 ingredients with a protein content of less than 16% can’t give a compound with 18% protein!!!

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FEED PRICES AND RELATIVE VALUES

Barley £140/tonne; Rapeseed meal £300/tonne. Values based on NE and UDP with RDP allowance

Price Relative Value

Wheat 140 141

Oats 130 116

Hipro soya 480 408

Wheatfeed 170 168

Beans 200 235

Peas 200 227

Beet pulp 200 130

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3. Rationing Suckler Cows

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Rationing Suckler Cows

OBJECTIVES

• produce viable calf at birth

• maintain cow health

• maximise reproductive efficiency

• high calf growth rates - milk

• least cost

• DRIVEN BY CONDITION SCORE

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Condition Scoring

• Simple Assessment of body condition from 1 (thin) to 5 (fat)

• Assessment of subcutaneous fat levels

• 2 main sites on body to assess C.S.

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Condition Scoring

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Condition Scoring

•Condition score 1 - The individual spinous processes are sharp to the touch and easily distinguished.

•Condition score 2 - The spinous processes can be identified individually when touched, but feel rounded rather than sharp.

•Condition score 3 - The spinous processes can only be felt with very firm pressure and the areas on either side of the tail head have some fat cover.

•Condition score 4 - Fat cover around the tail head is easily seen as slight mounds, soft to the touch. The spinous processes cannot be felt.

•Condition score 5 - The bone structure of the animal is no longer noticeable and the tail head is almost completely buried in fatty tissue.

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Target CS for Spring Calvers

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Spring Calver Feed Requirements

• Weaning to calving CS 3.0 at weaning, target 2.5 at calving, lose 0.5CS over

120d Flat rate feeding over last 16 weeks of pregnancy Cow weight kg weight change kg/d 550 -0.30 650 -0.35 75 MJME/d 750 -0.41 • Alternatively, feed at 80-85MJ until last 8 weeks, then reduce if necessary to avoid over-fat cows at calving • Post calving - as for autumn calver

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Example Diet for Spring Calver

• 75 MJ energy requirement

• 28 Kg average silage (ME 10.5MJ/Kg, 25% DM) – 75 MJ

• Plus minerals

• Autumn calver in November needs 120 MJ per day, spring calver 75MJ 45 MJ difference = 17Kg silage, or 4Kg barley

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Rules of Thumb

• Maintenance 0.11xW MJME/d

• Milk 5 MJME/kg milk

• Pregnancy (last 8 weeks) 15 MJME/d

• Weight loss 30 MJME/kg

• First calved heifer gain 0.3kg/d(10MJ)

• Dry Matter Intake 2% liveweight

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Body Condition at Calving and Reproductive

Performance

CS Calves Calving weaned

interval (d) per 100 cows to bull

Below 2 418 78

2 to 2.5 382 85

2.5 to 3 364 95

Over 3.5 358 93

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Suckler Rations

• Try to group cows according to condition

• Take particular care with 1st and 2nd calvers, and shy feeders

• CS2.5 at calving = 7.7% assisted calvings. CS 3.5 at calving = 14.3% assisted calvings!

• Autumn calvers – timing of energy demand very different to spring calver -120MJ/day in winter compared to 65-70 for spring calver

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4. RATIONING SHEEP

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NUTRIENT REQUIREMENTS OF PREGNANT EWES

• Maintenance

• Pregnancy – foetus and placenta

• Condition score (weight) change

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BODY CONDITION SCORE

Body Condition Score Targets

Hill Ewes Upland Ewes

Lowland Ewes

At Weaning 2 2 2.5

At Tupping 2.5 3 3.5

Mid- Pregnancy

2 2.5 3

At Lambing 2 2.5 3

At Weaning 2 2 2.5

0

0.5

1

1.5

2

2.5

3

3.5

4

Hill

Upland

Lowland

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BODY CONDITION SCORE

• Monitor condition regularly

• Group according to CS at weaning

• Lean group get priority grazing

• 8 weeks of good grazing will raise CS by 1

• Younger ewes will recover BC faster than older ewes.

• High energy/high intake feed blocks can help thin ewes or where limited quality grazing available to boost lambing % 10-20%

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EARLY & MID PREGNANCY

Early Pregnancy

• Minimise stress

• Maintain plane of nutrition – for at least three weeks post ram removal.

Mid-Pregnancy

• Ewes should not gain or loose more than half a BCS (5% of Body weight – 3-4kg)

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TARGETS FOR PREGNANT EWES

• Grass grazing 4-6cm Ideal.

• 1 unit CS = 0.13 x weight

70kg ewe, 1 unit=9.1kg, 0.5 units/56d=0.08kg/d weight loss

65kg ewe = 8.45kg

75kg ewe = 9.75kg.

80kg ewe = 10.4kg

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FEEDING LEVELS(70kg lowland ewe BCS 3)

Weeks before lambing: 8 6 4 2 1

Silage (11MJ/kg DM) 18% CP compound (kg/day)

Single 0 0 0 0.2 0.2

Twin 0 0 0.3 0.4 0.6

Triplet 0 0.2 0.4 0.6 0.8

Silage (10MJ/kg DM) 18-20% CP compound (kg/day)

Single 0 0 0 0.2 0.2

Twin 0 0.2 0.4 0.6 0.8

Triplet 0.2 0.4 0.6 0.8 1.0

Silage (9MJ/kg DM) 18-20% CP compound (kg/day)

Single 0 0 0.2 0.3 0.5

Twin 0.2 0.4 0.6 0.8 0.9

Triplet 0.3 0.5 0.7 0.9 1.2 43

FEEDING LEVELS

• Concentrate inputs should start 2 weeks earlier and be 0.2 kg/day higher than those shown in the above table when –

– ewes are in poor condition

– poorer quality silage is offered

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FEEDING LEVELS(70kg lowland ewe BCS 3)

Weeks before lambing: 8 6 4 2 1

Hay (9MJ/kg DM) 18-20% CP compound (kg/day)

Single 0 0 0.2 0.3 0.5

Twin 0.2 0.4 0.6 0.8 0.9

Triplet 0.3 0.5 0.7 0.9 1.2

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CONCENTRATES FOR PREGNANT EWES

• Compound feeds

Minimum 12MJ ME/kgDM

Protein content of 18%CP – no indication of quality (ERDP & DUP)

DUP good for colostrum quality and can lower worm burdens.

Good quality: cereals, cereal by-products, maize gluten sugar beet pulp, soya hulls.

Poor quality: oatfeed, olive pulp, shea nut, cocoa shells, coffee residues

List on the label: descending order of inclusion

Poorer quality feeds will result in extra feed being required which may compromise forage intake.

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CONCENTRATES FOR PREGNANT EWES

• Home mixes (kg/t):

18% 21%

Barley 575 475

Molassed s. beet pulp 100 100

Soya bean meal 150 200

Peas 150 200

Min/vit supplement 25 25

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MINERALS FOR EWES Trace Element When to sample

Copper

Swayback ill-thrift

•Ewes – pre tupping •Lambs at weaning •Cases of ill thrift

Blood – 7-10 Liver -3

Cobalt

ill-thrift Poor fertility Neonatal Losses

•Ewes pre tupping and pre lambing •Lambs at weaning •Cases of ill thrift

Blood –10 Liver -3

Selenium

ill thrift Poor fertility High Barren rate Still births White muscle disease

•Ewes pre tupping and pre lambing •Lambs at weaning •Cases of ill thrift

Blood – 3-5 Liver -3

Iodine Helps new born lambs to control body temperature and prevent hypothermia

Speak to vet Forage samples will also help

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MINERALS FOR EWES • Lamb vigour Vitamin E & Selenium – shown to increase lamb vigour at

birth. Moist grain diets increase demand. Iodine – essential to the newborn lamb to help control

body temperature and avoid hypothermia • Blood sampling – provide the most effective guide to

situation. • Energy intake and avoiding acidosis

– Introduce slowly – 0.25kg/d, increasing by 0.05 to 0.1kg/d – No more than 0.45kg/feed – Whole grains (except silage diets)

• Worm Burden will reduce uptake of nutrients and minerals.

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FEED BLOCKS

Type and typical intake

Cost per tonne £

Labour cost of feeding

% of daily energy Req. for

maintenance

% of daily min & Vit req.

60g hard poured bucket

620 V Low 10 60

0.15kg standard block 430 V Low 15 100

0.25kg premium energy block

460 Low 30 100

0.2l liquid feed 290 Mod. 20 10

0.15kg lifeline bucket 675 V Low 20 100

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FINISHING LAMBS

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FINISHING LAMBS Short keep Medium Keep Long Keep

35kg + 30-35kg <30kg

30-40days 40-70 days 70 days +

140-160g DLWG 90-110g DLWG 80-100g DLWG

Energy Energy & Protein Energy & Protein

Whole cereals 14-16%CP mix 17/18%CP Mix

Intakes of concentrate feeds will be 1-1.5kg/hd/day – build gradually risk of bloat & death.

FCR vary from 6:1 – 10:1

Animal health should be good – Worms/feet/ventilation

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FINISHING LAMBS

% inclusion

Whole Barley 75 72.5 80 82.5

SB pellets 12.5 0

Soya 10 0 5 5

Peas 0 25 12.5

Beans 10

Mins 2.5 2.5 2.5 2.5

15% CP ration.

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6. FEEDING BEEF CATTLE

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PHASES OF GROWTH

• Three phases of growth

– Rearing – birth to 200kg – target is for a well grown, weight for age

with no severe health challenges.

– Growing 200-450/500kg – target is for a well framed beast ready to

be finished. 0.5-0.8kgDLWG

– Finishing the last 60-90days – target DLWG 1-1.5kg to maximise

weight grade and KO%

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TARGET GROWTH RATES DLWG (Kg/day)

Birth to Weaning (suckled) 1.0-1.2

Winter (pre-summer grazing) 0.6-0.85

Summer grazing 0.8-1.0

Finishing period 1.0-1.5

Lower rates for heifers and earlier maturing breeds Higher rates from steers and continental breeds Avoid interruptions to steady growth rates –can delay finishing, reduce carcass and meat quality.

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CREEP FEEDING

• Increase calf weaning weights

• Typical FCR of approx 4:1 – 120kg creep=30kg lw gain.

• Improve cow condition

• Wean calves from thin dams earlier.

• More efficient to feed calf than cow

• 11-15%CP mineralised high energy ration.

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Concentrates for Weaned Calves

• Immature under-developed rumen

• Used to digesting milk (and creep), not

well suited to digesting long forage

• Will take many weeks for rumen to

develop fully 58

RATION GUIDELINES

Growing Cattle Finishing Cattle

Dry Matter intake 2.3% of body weight 2% of body weight

DLWG 0.6-1.3kg/day >1.4kg/day

Dry matter 30-60% 30-60%

Crude Protein (CP) 14-16% 12-15%

ME (MJkg/DM) 10.5-11.4 >12.2

NDF (neutral detergent fibre) >40% >25%

Fat <3% <6%

Starch & Sugar <20% >33%

Calcium 0.8% 0.6% 59

Concentrates for Weaned Calves

Constant Increasing Decreasing

1st 50 days (Kg/hd/day) 2 1 3

2nd 50 days (Kg/hd/day) 2 2 2

3rd 50 days (Kg/hd/day) 2 3 1

Start weight (Kg) 300 300 300

Finish weight (Kg) 425 420 430

Total concentrates 300 300 300

Total silage (t) 3.2 3.1 2.9

% silage at turnout 75 60 90

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Concentrates for weaned calves

• When turned out to grass, the animals on a 90% forage diet will have a rumen well suited to digesting forage – no “check” in growth

• Works best where calves have been creep fed prior to weaning

• If using decreasing pattern, introduce GRADUALLY

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Suckler Calves - Heifers

• Common issue with finishing suckler heifers – too small and too fat at slaughter

• Can be breed and genetic effects, and from weaning – 10 months is key

• Target diet to approx 0.6 Kg/day liveweight gain

• “Frame” growth until 300-350 Kg liveweight

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Compensatory Growth

0.20 0.30 0.40 0.50 0.60 0.70 0.80 0.90 1.00

Winter gain (kg/ day)

0.60

0.70

0.80

0.90

1.00

1.10

1.20

Sum

mer G

ain (kg/day)

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Compensatory Growth

• Winter gains - 0.46 and 0.8kg/day for 127days

• Difference in LWt at turnout - 43kg

• After 4months grazing - 50% compensation

• After 7months grazing - only 68% compensation

• Compensation hardly ever complete for grass finished

cattle

• Length of grazing season major factor

• Target winter gains 0.6 - 0.8kg/day

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GROWTH FROM GRASS

Sward height/cm

Conc Kg/d 6.5 7.8 9 10 11

0 0.84 1.08 1.17 1.21 1.2

1.6 0.95 1.11 1.19 1.2 1.22

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Conc kg/d Grass DMI (kg/d) DLWG (kg) KO%

0 9.6 0.51 52

2.5 9.5 0.82 53.9

5.0 8.8 1.05 53.7

GROWTH FROM GRASS

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GROWTH FROM GRASS

• Quality and quantity of concentrates fed determined by silage quality.

• Feed a max of 0.5kg cereals/compound per 100kg LW per single feed to reduce risk of acidosis.

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SILAGE QUALITY vs CONCENTRATES

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FINISHING CATTLE ON SILAGE BASED DIETS

IMPLICATION

• Point at which adding more cereals to silage diet :

– not beneficial

– may even reduce performance (substitution)

– increase risk of acidosis etc

• Safer and more effective to ad lib concentrates

and feed straw i.e. barley beef

• When concentrates make up 65-70% diet DM

- i.e. 7-8kg concs/day

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SILAGE QUALITY Silage ME (MJ/kg DM) 9.4 10.0 10.0 11.3

Conc (kg/hd/day) 3.3 2.5 5 2.5

Silage DMI (kg) 5.3 6.3 5.3 6.9

DLWG (kg) 0.78 0.96 1.22 1.18

KO% 54.2 56 56.5

Carcass gain (kg) 0.43 0.54 0.76 0.76

Increase in carcass weight 64.5 81 114 114

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SILAGE QUALITY Silage ME (MJ/kg DM)

9.4 10.0 10.0 11.3

Conc (kg/hd/day)

3.3 2.5 5 2.5

Silage DMI (kg) 5.3 6.3 5.3 6.9

DLWG (kg) 0.78 0.96 1.22 1.18

KO% 54.2 56 56.5

Carcass gain (kg) 0.43 0.54 0.76 0.76

Increase in carcass weight

64.5 81 114 114

Days to grow 100kg(lw)

128 104 82 85

Cost 100kg gain £168 £110 £158 £91

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DUNG SIGNALS What does Manure look like Possible dietary causes (not disease)

Loose manure •High protein (total or soluble); pasture •Insufficient fibre in ration

Diarrhoea

•Spoiled, mouldy feed or silage •Ruminal acidocis •Increased hindgut fermentation

Foamy manure or mucin casts (pieces of gut lining that indicate gut damage)

•Ruminal acidocis •Increased hindgut fermentation

Large particles of undigested feed

•Cattle sorting feed, slow feeding •Not enough chewable fibre/forage/feed •Ruminal Acidosis

Manure variable in group •Cattle are sorting feed; feeding slowly •Spoiled, mouldy feed or silage

If rumen is working well, you should see: Few feed particles over 1.5cm long, little recognisable feed, 80% of cattle not sleeping, eating or drinking should be ruminating

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Intensive Beef SYSTEM

• Ad-lib high energy concentrates and straw

– cattle eat about 13% DMI as straw

– long straw increases LWG by 0.1kg/day

• High average LWt gains 1.3 - 1.5kg/day

• Finish at 12 - 14 months of age

• Good FCR

• Was/is Low cost/kg LWG? – know your costs!

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Intensive Beef

Option 1 Option 2 Option 3

Quality of ME (energy) most important, DO NOT overfeed protein.

Barley 90% 40% 34%

Wheat 40% 38%

HiPro Soya 10%

Peas 28%

Beans 20%

plus intensive min/vit supp.

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Intensive Beef

• Cereal processing important

–minimum processing

– roll to half or a third original thickness

– some whole grain in dung

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Protein sources for intensive beef

450kg steer gaining 1.5kg/d Clean, long straw to appetite Barley 8.9 9.2 8.7 8.4 8.2 7.5 Soya 0.9 - - - - - Rapeseed - 1.2 - - - - Wheat DG - - 1.6 - - - Maize DG - - - 1.7 - - Beans - - - - 1.9 - Peas - - - - 2.2 plus intensive min/vit supp.

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INTENSIVE BEEF • Barley/wheat/oats - high starch foods

– lowest FCR, lowest cost/kg LWG

• 2 week minimum build-up to ad lib intake

– start with 16 -17% protein - helps with adaptation

– 2 feeds of 2kg/day

– introduce a third midday feed

– increase quantities until feed left

– fill hoppers and if hoppers get empty, start again

– In last 8 weeks before slaughter, reduce protein in ration to

encourage fat deposition

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MAXIMISE DM INTAKE

• Smooth, clean surface

• Eating surface – about 10cm above hoof

• Brisket board to prevent pulling though of feed

• Clear away refused food – x3 week

• Careful siting of water

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FEED SUPPLEMENTS

79

LIVE YEAST SUPPLEMENTS

• Mop up oxygen

• Stabilise rumen pH

• Increase rate of fibre digestion

• Provide growth factors for microbes

• Boost protein supply

• Reduce methane production

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YEAST and PERFORMANCE

• Harper Adams UC: Bulls & heifers barley/soya

Yea-Sacc Control Start wt kg 285.5 282.1 Slaughter wt kg 520.4 520.1 Days to slaughter 169.3 190.3 LWG kg/d 1.38 1.24 Feed intake kg/d 8.1 8.73 FCR 5.87 6.98 Cost/kg gain p/kg 67 78

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Yeast and Other Supplements

• Yeasacc, Biotal, Crina, etc

• Check inclusion rates and cost

• If with minerals, likely to be more expensive and less accurate for both supplement and minerals – include separately

• Blocks with minerals and/or supplements NOT suitable for finishing diets (or any other diet?)

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TAKE HOME MESSAGES

1. Know your stock

Weights and condition

2. Know your feeds

Quality of available feeds

3. Set targets and ration accordingly

Maximise animal performance

Value ££.

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MINERAL & VITAMINS

Major Minerals Trace elements Vitamins

Calcium (Ca) Cobalt (Co) A

Phosphorus (P) Copper (Cu) D

Magnesium (Mg) Iodine (I) E

Potassium (K) Iron (Fe)

Sodium(Na) Manganese (Mn)

Sulphur (S) Selenium (Se)

Zinc (Zn)

84

MINERALS FOR CATTLE

Trace Element

Copper Essential in enzyme function

•Poor growth •Scouring •Infertility •Reduced pigmentation

Cobalt Energy Metabolism •Lethargy/weak •Poor appetite

Selenium Immune function •Ill thrift •Infertility

Iodine Energy Metabolism Foetal development & growth

•Weak newborns •Retained afterbirths

Close interaction between most vits and mins. Speak to vet Blood sample to confirm deficiency. Forage samples will also help

85

MINERAL & VITAMIN SUPPLEMENTATION

• Always needed with home-grown feeds or un-mineralised blends or straights

• Use of compound feeds reduces or eliminates need

• Mixed and varied diets less likely to be deficient than single feeds

• Free-Access Minerals: very variable intake

86

MINS & VITS - SPECIAL CONSIDERATIONS

• Urea treated grain or ammonia treated straw need Sulphur

• Brassicas need Copper, Iodine, Selenium

• Intensive diets - Ca:P>2:1; P<4.6g/kgDM; Mg<2.3g/kgDM

• Hypomagnesaemia – extra available Magnesium at risk periods

87

MINERAL RATES

Ration A Ration B

Silage 18kg 16kg

Barley 2kg 4kg

Min/vit 100g 100g

100/2=50g/kg 100/4=25g/kg

50kg/tonne 25kg/tonne

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TRACE ELEMENT SUPPLEMENTATION

Cost - £ Effectiveness Ease of Use

Free Choice Minerals

£ * ***

In Feed Minerals £ ** ***

Drench £ ** **

Injections ££ *** **

Bolus ££ *** *

Top Dressing Pasture

£££ * **

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END

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