Thursday, 28 June 2018 14:55

Caring for cows on crops

Written by  Helen Thoday, animal care team manager at DairyNZ
Helen Thoday. Helen Thoday.

Wintering cows on crops is a common strategy to help keep them in good condition, but it may result in them getting sick. 

Farmers can reduce this risk in several ways. 

Monitor the herd carefully and keep an eye out for sick cows or those not keen to feed when the rest of the herd is feeding.  

Treat sick cows promptly, especially in poor weather, and call your vet as soon as possible. 

To speed up a sick cow’s recovery, provide a suitable recovery site such as a grass paddock with good shelter, a low stocking rate and extra, highly palatable feed and water. 

Your vet will advise you on the best recovery plan for your stock.

Think carefully about weather when wintering cows on crops. 

Cattle tolerate cold conditions by making physical changes, i.e. thickening their skins and coats and drawing on their fat reserves. 

If a cow is clean and dry and there is little wind or rain, cold stress is rare until ambient temperature falls below -10°C.

The factors that increase the risk of cold stress are very low temperature, wind, rain and mud, low condition scores and low feeding levels.

During periods of cold and wet, the energy required by cows can increase by at least 12 MJ ME/day depending on the severity of the conditions. Also, cows’ feed utilisation may decline, increasing the gap between energy intake and requirement. To keep cattle in the right condition during extreme winter weather offer additional feed.  

For a typical crop-based wintering diet aimed at gaining 0.5 BCS units during a dry period, during mild weather a 500kg cow needs to eat about 124 MJ ME/day. Typical diets to provide this include:

9.5kg kale and 4kg average quality pasture baleage (assuming 80% utilisation of the crop and 85% utilisation of the baleage) 

9.8kg DM swede and 4kg average quality pasture baleage (assuming 80% utilisation of the crop and 85% utilisation of the baleage)

8.3kg fodder beet and 3.5kg average quality pasture baleage (assuming 90% utilisation of the crop and 85% utilisation of the baleage).

If this same cow were exposed to prolonged cold and wet conditions, then her energy requirement would increase to at least 136 MJ ME/day.  To achieve this increased energy requirement, assuming the same feed utilisation, either provide more crop or more supplement. 

For a herd of 160 cows this extra energy could be provided by an extra bale/day of average quality pasture silage (220kg DM equivalent, 10 ME) or additional crop: 

Kale: 160m2 for 160 cows grazing a 12t crop (1.2kg DM/cow)

Swedes: 120m2 for 160 cows grazing a 16t crop (1.2kg DM swedes)

Fodder beet: not recommended because it requires at least an additional 1kg DM/cow/day which could result in digestive upsets in some animals even when they were fully transitioned. 

Depending on the BCS of the herd, and the weather, wet and windy conditions require an additional 0.5 - 3kg DM/cow/day. 

For more information visit https://www.dairynz.co.nz/feed/crops/wintering-cows-on-crops/winter-crop-management/

• Helen Thoday is animal care team manager at DairyNZ

More like this

Turning data into dollars

If growing more feed at home adds up to $428 profit per tonne of dry matter to your bottom line, wouldn’t it be good to have a ryegrass that gets you there quicker?

Featured

Carrfields invests in new Ashburton R&D hub

The Ashburton-based Carrfields Group continues to show commitment to future growth and in the agricultural sector with its latest investment, the recently acquired 'Spring Farm' adjacent to State Highway 1, Winslow, just south of Ashburton.

Elite sheep dogs to go head-to-head at Ashburton A&P Show

A major feature of the Ashburton A&P Show, to be held on October 31 and November 1, will be the annual trans-Tasman Sheep Dog Trial test match, with the best heading dogs from both sides of the Tasman going head-to-head in two teams of four.

National

Machinery & Products

New pick-up for Reiter R10 merger

Building on experience gained during 10 years of making mergers/ windrowers, Austrian company Reiter has announced the secondgeneration pick-up on…

Krone EasyCut B1250 fold

In 2024, German manufacturer Krone introduced the F400 Fold, a 4m wide disc front mower, featuring end modules that hinge…

» Latest Print Issues Online

Milking It

Microplastics problem

OPINION: Microplastics are turning up just about everywhere in the global food supply, including in fish, cups of tea, and…

Job cuts

OPINION: At a time when dairy prices are at record highs, no one was expecting the world's second largest dairy…

» Connect with Dairy News

» eNewsletter

Subscribe to our weekly newsletter