Silage Advisory Centre

Mr Brandon out-winters spring-born calves as well as in-calf heifers on a system equally suitable for beef producers.

Whilst the year-on-year cost saving and animal health benefits are justification in themselves, the initial rationale for out-wintering was that it allowed the farm to substantially increase herd size and continue rearing its own replacements without the need for additional buildings. Furthermore, as the 26ha used for out-wintering is rented from neighbouring arable farms, the system helps with NVZ compliance by easing stocking rates.

New Buildings Farm is now an entirely grassland unit supporting just over 400 New Zealand Friesian and Jersey cross milking cows on an extended grazing system. Cows are tightly block-calved from February to April and produce close to 6,000 litres from grass and just 480kg/cow of concentrates. Key to such a system is rearing heifers to calve successfully at two years old.

As Steve Brandon explains, attaining the necessary bulling and calving weights is in no way hampered by out-wintering.

“Spring-born calves are weaned off milk at 8-10 weeks of age and are grazed on grass with no supplementary feeding at all from late May,” he says. “These calves will strip graze Swift hybrid brassica from late November to February, during which time they have access to baled grass silage.

“The heifers then go back onto an out-wintering system the following autumn when in-calf, and stay outside until January when they come inside prior to calving.

“We are achieving average growth rates of 0.7kg/head/day on this system and see none of the problems typically associated with housing, such as pneumonia. Heifers will typically calve down at around 500kg.”

With the entire acreage at New Buildings Farm needed to meet the herd’s grazing and silage requirements, Mr Brandon looks to his arable farming neighbours for the land for out-wintering.

Crops are typically direct drilled into cereal stubbles at the end of August, receiving a top dressing of fertiliser but no sprays at all. Taking into account land rental and all the growing costs, plus fencing, labour and silage bales at £15 each, Mr Brandon works out the cost of the out-wintering system to be 69p/head/day, which compares favourably with the estimated £1.40/head/day if cattle were housed.

Good site selection and forward planning are essential in order to maximise utilisation when out-wintering, as well as the correct crop choice, as Helen Mathieu of British Seed Houses points out.

“The advantage of hybrid brassicas such as Swift and Redstart is that they combine the rapid growth characteristics of forage rape with the winter hardiness and yield potential of kale. They can be grown as catch crops after cereals and achieve yields of around 6 tonnes DM/ha from a single grazing, or sown earlier in the season to achieve yields of 10 tonnes DM/ha. They can also produce regrowths for a second or even third grazing, provided they are managed appropriately.

“The important points with out-wintering include selecting sites that offer the stock some shelter, ideally with a run-back area. It is essential to calculate how much the stock require on a daily basis and make this available through long and narrow daily allocations. Brassicas should be supplemented with a fibre source such as hay, silage or straw, and this should be placed in the crop during the crop establishment phase when ground conditions are suitable. You do not want to be creating ruts by needing to access the fields with tractors during the feeding phase.”

Access to water is also essential, as is adequate provision of minerals. As to the question of cross compliance, there should be no issues for well-managed out-wintering systems that avoid the risk of run-off and adhere to the common sense practice of good site selection and preparation.