Bovine Nutrition and Metabolic Disease 3 - Ration Formulation

Question 1

2 basic ways to rear calves?

Answer 1

Suckle system / cow-calf operation.
- calf reared with cow and suckles from cow.
Artificial rearing system.
- calf receives colostrum from cow, then removed from cow and fed with either milk or a milk substitute.
– whole milk / waste milk (not great) / milk substitute (not always entirely milk) (added variables such as temperature and concentration).

Question 2

1. Consistent preparation of milk substitute?
2. Other factors that need to be kept consistent when feeding calves?

Answer 2

1. 150-175g/L concentration.
   - affects milk clotting in the abomasum.
   Temperature.
   Slow changes in volume / concentration only!
2. Order of feeding and time of day.
   - reduce stress and excitement.
   - controlled and slower drinking to digest milk properly.

Question 3

1. Consistent presentation of the milk to the calves.
2. 3 C’s?

Answer 3

1. Raised buckets / Wyedale feeder.
   Individual buckets.
   Regular cleaning.
   Low number of calves per teat.
2. Cleanliness.
   Concentration.
   Consistency.

Question 4

1. As well as milk, what else should calves have constant access to?
2. Feeding compound feed to calves.
3. Summarise what calves need to ingest.

Answer 4

1. Ad lib clean fresh water.
   - for hydration.
   - enables feeding of forage and concentrates to develop the rumen.
2. Calf pellets or course mix.
   CP 18% (increased DUP e.g. soya).
   Constant free access.
   Aim for 0.75-1kg/day growth rates by weaning.
3. Milk - at least twice daily.
   Forage - straw.
   Concentrate / creep feed - rumen microbes need a source of protein.
   Water - ad lib, fresh, clean.

Question 5

Supplying calves with roughage.

Answer 5

Good quality barley straw (or hay).
Constantly available.
Stimulates rumen development (scratchy).
Feed from a rack.
- cleanliness (NB coccidiosis).
- maximise DMI.

Question 6

1. When are spring-born beef suckler calves usually weaned?
2. When are autumn-born beef suckler calves usually weaned?
3. At what age are dairy calves normally weaned?

Answer 6

1. The following autumn.
2. The following summer.
3. At 6-8wks old.

Question 7

Intensively reared beef cattle?

Answer 7

Cereal/barley beef.
- fed predominantly cereals
– barley.
–> grain.
—> not much fibre.
—> rapidly fermentable carbohydrate&raquo_space; lots of acid&raquo_space; rumenal acidosis.
- also have access to straw.
- need additional protein supplementation.
- efficiently allow finishing young (10-12mths).

Question 8

Cereal/barley beef management and feeding?

Answer 8

Dairy / Dairy x Continental.
Housed all year round.
Finish at ~12mths / 500kg.
DLWG ~ 1.3kg/day.
Ad lib rolled barley + protein premix with mineral and vitamins.
Ad lib fresh barley straw (~1kg/day).
- high in phosphorus, if not enough calcium, can get spontaneous bone fractures.
- can get hypovitaminosis A and blindness.

Question 9

Grass silage beef system.

Answer 9

1kg/day DLWG.
16mths / 525kg finish.
1 tonne cereal, 40kg protein concentrate, 6 tonnes silage.

Question 10

18 month beef system.

Answer 10

0.8kg DLWG.
18mths / 500kg finish.
1 tonne concentrates, 5 tonnes silage.

Question 11

Extensive beef system.

Answer 11

0.6-1kg DLWG.
22-24mths / 550-600kg finish.
0.5 tonnes concentrates and 5 tonnes silage.

Question 12

Feeding the beef suckler cow.

Answer 12

Usually tight calving pattern (spring/autumn).
Calves at 7-9mths of age (or younger/older).
Milk yield:
- 8-11L in first month.
- 5-6 as lactation progresses.
Summer grazing.
Winter forage - silage +/- straw.
Loose housing.
May need some vitamin/mineral/ protein supplementation.
Minimise feed costs by max production from grass.
BCS management.
- calve at low BCS in spring, gain BCS over summer with grazing, lose BCS again through winter.

Question 13

Objective of a beef suckler system?

Answer 13

Produce a calf per year per cow at the least cost.

Question 14

ME requirements in suckler cows.

Answer 14

Similar to dairy cows.
Pregnancy:
- 25wks – 5MJ.
- 30wks – 10MJ.
- 35wks – 20MJ.
- 40wks – 45MJ.
Lactation - 5MJ/L.

Question 15

Dairy feeding system.

Answer 15

Feed mixed ration or feed component (concentrate and forage separately).
- concentrate feeding can be in the parlour, out of the parlour, mid-day feeds, in mixed ration.
- forage and concentrate systems allow individual feeding.
- forage can be self feed – reduce intake, can be dangerous.
- forage can be fed from trough or feeder or from floor – can affect palatability.
- Mixed rations mixed in wagons with weighing scales and mixer to measure and combine components of the ration. – increase palatability by adding water etc.
– increase DMI, increase yield, improves rumen function and reduces acidosis, cheaper with straights, not concentrates.
– is a capital investment, requires storage and time, can get fat cows, can be slow into the parlour, cash flow issues.

Question 16

Partial mixed rations.

Answer 16

Mixed ration fed outside of the parlour.
Small amount of concentrates fed in parlour.

Question 17

What is best if got multiple groups on a farm?

Answer 17

Have partial mixed ration with different ration and different concentrates given to each group.
++ increased precision, avoid fat/thin cows, improved management, reduce standing times helps with lameness.
– increased bullying when animals are moved. increased complexity, increased time.

Question 18

1. What does feeding to yield mean?
2. What does flat rate feeding mean?
3. Stepped feeding system?

Answer 18

1. Measuring milk yield per week and calculating concentrate to modify ration each week.
   - works well with smaller herds.
   - means do not waste food for cows that do not need it.
   - steeper lactation curves.
2. Where all cows and groups fed the same.
   - flatter lactation curve.
3. Mid-point between feeding to yield and flat rate feeding.
   - Early lactation, mid-lactation, late lactation groups each fed differently.

Question 19

Feeding to yield - what is fed?

Answer 19

Ad lib forage.
Concentrate according to yield.
- increased yield, increased concentrate (~0.3-0.4kg/L).
- “Lead” or “challenge” fed early in lactation to avoid reduced DMI.
- after peak, increased yield, increased concentrate.

Question 20

Fat rate feeding - what is fed?

Answer 20

Ad lib forage.
Concentrate based on target yield.
- predicted total concentrate intake for lactation calculated.
- divided equally for every day of lactation.
Total yield similar but longer, flatter lactation curve.

Question 21

1. Feeding to yield advantages?
2. Feeding to yield disadvantages?
3. Flat rate feeding advantages?
4. Flat rate feeding disadvantages?

Answer 21

1. Simple, avoids overfeeding / underfeeding.
2. Increased acidosis, increased metabolic stress, steep decline after peak lactation.
3. Simple, reduced metabolic stress, reduced acidosis.
4. Risk of underfeeding / overfeeding, increase BCS loss around peak.

Question 22

Stepped feeding - what is fed?

Answer 22

Ad lib forage and concentrate in parlour.
Stepped levels of concentrate e.g. 9kg first 100d, 6kg second 100d, 3kg third 100d.

Question 23

Ration formulation?
Considerations for ration formation?

Answer 23

Computer-based.
- e.g. DietCheck, Rumnut.
- “Fag packet” calculations for DMI and energy, but protein more difficult.
Remains a best guess based on info provided.
What the animals actually do is most important.
Considerations:
- level of production expected / required (energy, protein, minerals).
- farm policy/ethos.
- animal type.
- labour.
- feed/forage availability.

Question 24

Key questions to consider when formulating a ration?

Answer 24

What DMI is likely to be achieved?
How much energy is required?
What energy density will be needed?
How much protein is required?
What forages are available?
What is the quality of the available forages?

Question 25

Formulating diets?

Answer 25

Calculate DMI, ME and MP requirements.
Forage forms basis of diet but inadequate to supply ME and MP.
- grass silage: 10.5MJ and 15% CP.
- maize silage: 11.5MJ and 9% CP.
Specify base.
Identify available supplementary feeds.
Iterate to meet animals requirements.
Add minerals and vitamins.
Supplementary feeds:
- forage type / quality / quantity.
- energy or protein.
- availability and storage.
- location and cost.
- farm history.
Energy feeds:
- wheat (13.6MJ/kg DM).
- molasses (12.7MJ/kg DM)
– increases palatability.
- fat (35MJ/kg DM).
Protein feeds:
- rape seed meal (418g/kg).
- soya bean meal (504g/kg DM).
- high energy contents (12 and 13.5 MJ/kg DM respectively).