Winter Feeding: A guide to feeding adult dairy cows through winter

You can feel the chill in the 5am air. Winter is coming. And that means it’s time to forward-plan your adult dairy herd’s winter feeding regimes. Cows don’t like change, so as they move indoors it’s crucial to keep dietary alterations as non-disruptive as possible. Minimise change, maximise production.

Here’s a quick guide.

BRINGING COWS IN FROM THE COLD

While Jack Frost is working overtime through the winter months, it’s too cold for your cows to be outside. (A bovine’s body temperature needs to stay around 38˚C.i) But as well as a change in surroundings, bringing your cows indoors also spells a change in diet - from grazing on fresh grass to eating grass silage or other forages. It’s crucial to manage this transition carefully. To remain as productive as possible, adult dairy cows require a steady diet that gives them all the necessary nutrients.

WHY COWS ARE FUSSY FEEDERS

Four stomachs aren’t always a blessing. It takes the microflora in the rumen three weeks to adjust to any ration change, during which time food may not be digested as efficiently as it should be - potentially leading to nutrient loss. Any changes should be made gradually.

With the dairy herd this usually means gradually increasing the buffer feeding of trough rations as access to fresh grass becomes impractical. Again, the easier the transition, the more productive your herd is likely to be.

BEWARE THE BUFFER RATION

When formulating a buffer ration to be fed alongside grazing, make sure the content does not present a rumen acidosis risk. Some cows - particularly those that are lame - may choose to feed solely on buffer ration in preference to grazing.

GRASS QUALITY IS HIGHLY VARIABLE

Before planning your over-winter feeding, it’s important to note what your herd is used to. Grass quality varies from region to region - and even from one farm to anotherii - in terms of energy, protein and dry matter content.

AUTUMN GRAZING QUANTITIES

Extending natural grazing into the autumn requires knowing the dry matter of your grass. Dry matter reduces naturally as the season progresses, which in turn affects the quantity of grass a cow needs to consume to stay healthy and productive. For example, in order to consume 10kg of dry matter when the grass is at 20% dry matter, the cow needs to eat 50kgs of fresh grass. If the dry matter of the grass drops to 15%, the cow needs 66kgs of fresh grass.

OPTIMUM DRY MATTER OF FORAGES

Similarly, calculating the dry matter of grass silage and forages is crucial to making sure your cows get the nutrients they need to stay healthy and productive through the winter. The ideal silage should be cut at 16%-20% dry matter, and harvested at 30%-35% for a pit and 35%-40% for baled silage. This will help ensure the best fermentation and optimum intakes.

How to calculate dry matter of samples

TIME TO PLAN YOUR WINTER FEEDING

Now is the time to begin planning and preparing your winter feeding regime and stocks. The first step is to assess forage stocks in order to plan rations to spread forage usage across the winter period. Volume of forage in the clamp is calculated and then multiplied by the estimated forage density using the following table.iii

winter feeding silage density table

NB: Grass, maize and wholecrop silages are of a similar density for stocks estimation purposes.

If your forage stocks are limited, now is the time to investigate availability and cost and nutrient content of forage replacers - such as pressed pulp - that can be fed to your dairy herd for a healthy, happy and productive winter. Over to you.

References:

i OMAFRA: Hot tips for cool cows - omafra.gov.on.ca/english/livestock/dairy/facts/info_hottips.htm [accessed 24.08.16]

ii AHDB Dairy: Latest grazing measurements - https://dairy.ahdb.org.uk/technical-information/grassland-management/forage-for-knowledge/latest-measures/#.V-pgKPkrJD8 [accessed 11.10.16]

iii AHDB Dairy: Feeding+ - Planning your feeding - https://dairy.ahdb.org.uk/resources-library/technical-information/feeding/feedingplus-section-3-planning-your-feeding/#.V_IzHfkrJD8

For further information, please see the product SPC, or contact your veterinary surgeon, SQP or Zoetis UK Ltd, Walton Oaks, Dorking Road, Walton on the Hill, Tadworth, Surrey, KT20 7NS. Customer Support 0845 3008034. www.zoetis.co.uk. Always seek the advice of your medicines provider. Use medicines responsibly (www.noah.co.uk/responsible).

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