Feeding livestock: The benefits of grass vs other feeds

A long winter and wet spring have exhausted forage reserves on many farms. So, while conditions allow, it is important to maximise grazing opportunities when feeding livestock. Crucially, grazed grass is much more cost-effective compared to other feeds, explains grassland expert Harley Brown-Keech.

Relative costs of grazed grass vs other feeds

When comparing pence per megajoule (MJ) of metabolisable energy (ME), grass is much more cost-effective than other feed options. The largest difference is between grazed grass and concentrates, which are 2.20p/MJ of ME in DM more expensive in the table below.

Cost of livestock feeds

*Direct drilled

Source: John Nix Handbook 2024

While grass silage is 0.70p/MJ more expensive than grass, it is 1.50p/MJ cheaper than concentrates. So, when preparing for winter, grass silage can still be cheaper than concentrates.

Ultimately, grazed grass is the most cost-effective source of quality feed for livestock. When comparing cost per tonne of DM, grass is £280 cheaper, further highlighting its cost-effectiveness.

Advice for feeding livestock with grass

Feeding livestock with grass will help control costs, ensuring you can conserve forage and deploy concentrates when they are most impactful – for example: when finishing. This should be your preferred strategy to maximise profit and operate more sustainably.

Weather permitting, aim for an early turnout as the feed value of spring grass is similar to concentrates at this point. If grazing ground is still soft, grass silage can be used, if available.

When grazing, the ideal growth stage is when grass has three leaves. This helps maximise growth and yield because grass will have the optimum leaf area to capture sunlight. AHDB has found that grazing below the two-leaf stage can decrease growth by up to 85%.

To maximise grassland production, your grazing strategy is also crucial. To ensure high utilisation, rotational or paddock grazing are more effective grazing systems than set stocking or continuous.

Comparing grazing systems

Source: AHDB

Switching to rotational or paddock grazing can increase annual yield to 10.2t DM/ha. Meanwhile, paddock grazing can deliver 80% utilisation and 8.2t DM/ha of useable yield. Thus, investing in electric fencing and water troughs can significantly improve forage production.

Best forage options for feeding livestock

Autumn is an ideal time to plan your forage production ahead of spring. Weather-permitting, reseeding with high-quality grass and forage can increase the production of older pasture.

Grazed grass is a natural source of protein and Germinal’s Aber High Sugar Grasses improve protein use efficiency by providing more water-soluble carbohydrates (WSC) to the rumen.

This provides the rumen with extra energy, helping it capture more protein from grass, which can drive liveweight gain by 20% and milk production by 6%.

The high WSC in Aber HSG also ensure less protein is wasted as ammonia and nitrous oxide emissions. With Aber HSG, you can increase livestock production while also helping the environment.

Offering 27% crude protein, white clover can be a game-changer in grazing leys by increasing DM in perennial ryegrass leys. See below how it compares with grass and nitrogen applications of 200kg N/ha/year. Grazing grass and white clover can be even more cost-effective than concentrates.

Grass-only swards vs grass and white clover

Source: IBERS

White and red clover can both naturally fix around 150kg of nitrogen per hectare per year in soil. While helping to reduce input costs, grass-clover swards are also sustainable by requiring much less artificial fertiliser when established.

Like white clover, red can also boost grass performance. With quality grass silage containing 12-14% protein, a mixture with red clover can lift this to 16-20%. Click here to learn more about red clover silage.

To further enhance grassland production, consider combining grass with multi-species. Germinal Horizon research has found that a nine-component multi-species mixture produced 33.1% more yield compared with a grass-only sward.

Multi-species swards can provide a more consistent supply of quality forage through the different grazing seasons. As well as production, multi-species can improve soil fertility and structure.

Ask a forage expert

For advice on feeding livestock with quality homegrown forage or to refine your plans ahead of spring, contact your local Germinal expert.

William Fleming, Area Sales Manager (Scotland, Northeast England)

T: 07971640428

E: [email protected]

Paul Morgan, Area Sales Manager (Southern England, South Wales)

T: 07713 878069

E: [email protected]

Harley Brown-Keech, Area Sales Manager (Central England, North Wales)

T: 07880469645

E: [email protected]