Outwintering livestock: Implementation

Ensuring livestock receive balanced nutrition in bale-grazing systems is essential for maintaining their health, productivity and maintenance. It can be helpful to analyse your deferred grazing and hay as this will provide valuable insights into the quality of the diets and their suitability for your livestock.

Assessing available forage in kg DM/ha means grass can be rationed according to livestock requirements. 

Without accurate allocation there is a risk of: 

• Underestimating available forage and wasting a low-cost feed source 

• Overestimating forage availability, resulting in loss of body condition and reduced performance 

• Reduced grazing efficiency and poorer pasture utilisation 

Deferred grazing requires a flexible approach and regular monitoring. Aim for dense swards with a high proportion of leaf material to maximise forage quality. 

Permanent pasture and long-term leys are generally best suited to winter grazing due to their dense sward structure and reduced risk of soil damage. 

Use the results from forage analysis to inform your dietary choices to support the nutritional needs of your cattle at different stages.

Suckler cows (maintenance requirement) need a minimum of 9% crude protein (CP) and 9 MJ ME/kg DM to sustain body condition.

Growing and finishing youngstock need more nutrients, with a target of 11–13% CP and 10–12 MJ ME/kg DM, depending on growth stage and target weight gain.

Deferred grass

• Sufficient to meet maintenance needs for protein and energy
• May not provide adequate ME to support significant growth or finishing

Hay

• Lower-quality hay (e.g. 7.1 MJ ME/kg DM and 7.6% CP) falls short of maintenance requirements if fed alone
• When combined with deferred grass, hay contributes to a balanced diet that meets livestock needs

Estimate available forage

Next, calculate the total forage available from both deferred grass and bales. 

Deferred grass

Before the start of winter, paddocks should be rested to build up forage reserves.

Ideally, deferred grass should have 3,000–4,000 kg of dry matter (DM) per hectare. Measure pasture cover in the autumn to estimate the available DM.

For example, if you have 10 hectares with 3,500 kg DM/ha, the total available deferred forage is 35,000 kg DM. However, you need to take residue into consideration. 

Hay bales

When using hay bales, calculate the amount of DM provided by each bale.

A typical 4-foot round bale weighs approximately 400–450 kg fresh weight, with around 80–85% DM content. One of these bales would, therefore, provide 320–380 kg DM.

Target grass covers

Knowing your target grass covers can help you plan ahead and maximise grass utilisation.

Recommended targets 

• Entry cover: 3,250 kg DM/ha 

• Exit cover: 1,500 kg DM/ha 

• Average farm cover before winter: 2,000-2,500 kg DM/ha 

Maintaining appropriate residuals helps: 

• Reduce wastage 

• Improve tiller density 

• Improve spring grass quality 

• Protect soil structure

Feed budgeting is essential to ensure livestock have adequate forage throughout the winter.

By combining bales and deferred grass, you can strike a balance between feed supply and grazing demand while minimising feed waste and pasture damage.

How to plan and manage feed efficiently

The first step in feed budgeting is calculating how much forage your livestock will need.

This depends on several factors, including the type and number of animals, their body weight and expected intake.

The dietary requirements of a mature cow during the winter period depend on factors such as pregnancy status, body condition score (BCS), breed and environmental conditions. Nutritional targets include:

Energy requirements (metabolisable energy (ME))

• Dry cows (maintenance): 9 MJ ME/kg DM
• Pregnant cows (mid to late gestation): 10–11 MJ ME/kg DM (increasing in late gestation)
• Lactating cows (early lactation): 11–12.5 MJ ME/kg DM

Energy intake must support maintenance, pregnancy and lactation, while also taking into account colder weather, which increases energy demands due to heat loss.

Protein requirements (crude protein (CP))

• Dry cows: > 9% CP
• Pregnant cows (mid gestation): 10–11% CP
• Late-gestation and lactating cows: 11–13% CP

Now that you know how much forage your livestock will need, and how much you have available, you need to match the supply to the demand. 

Forage allocation

If you plan to use both deferred grass and bales, divide the total available feed into daily or weekly allocations.

For example, if you have 100 cows needing 1,500 kg DM per day, you could allocate part of that from deferred grass and part from bales.

If your deferred grass provides 30 kg DM per hectare per day, and you have two hectares, you will need to make up the remaining 1,440 kg with hay bales (about four or five bales per day).

Daily dry matter (DM) and energy requirements

Livestock typically consume 2–3% of their body weight in dry matter per day.

Estimate available forage and energy

Evaluate forage supplies for both DM and energy content.

Deferred grass

Grass energy content varies but typically ranges from 9–11 MJ ME/kg DM.

Hay bales fed on the ground

Hay energy content varies from 8–10 MJ ME/kg DM, depending on quality. Assume a typical bale provides 9 MJ ME/kg DM.

If hay bales are fed on the ground with a 65-75% utilisation rate, the available dry matter (DM) and energy. Therefore, 75% of the bale is consumed instead of 100%.

If hay is fed on the ground, utilisation rates typically range from 50% to 75%, depending on factors such as:

• Weather conditions (wet/muddy conditions increase waste).
• Stocking density (higher density can lead to more trampling and fouling).
• Feeding frequency (daily feeding reduces waste compared to ad lib feeding).

Forage allocation

Allocate forage and energy resources to meet livestock requirements.

If you have 50 cows, each requiring 77 MJ ME/day, their total daily energy demand is:

• 50 x 77 MJ ME/day = 3,850 MJ ME/day

If grazing deferred grass provides 2,000 MJ ME/day (e.g. 2 hectares grazed daily at 10 MJ ME/kg DM), you need to provide an additional 1,850 MJ ME/day from hay bales:

• 1,850 MJME/day divided by 3,060 MJ ME/bale = 0.6 bales/day

Every feed budget should include contingency plans. Consider: 

• Snow cover 

• Heavy rainfall 

• Frozen ground 

• Extended wet periods 

Emergency forage reserves should be available in the form of: 

• Silage 

• Hay 

• Sacrifice paddocks 

Additional considerations 

• Increase allowances during wet and windy periods 

• Move livestock more frequently in wet conditions 

• Protect productive grazing areas from poaching 

• Monitor soil compaction risk 

Throughout winter monitor: 

• Body condition score 

• Liveweight performance 

• Grass covers 

• Remaining forage stocks 

• Ground conditions 

If livestock performance falls below target: 

• Increase supplementation 

• Reallocate grazing areas 

• Adjust stocking pressure 

• Consider housing vulnerable stock 

Further information and next steps