Roles for Silage in Beef Enterprises

Introduction

The challenge in using silage in beef enterprises is to consistently meet selected market specifications, on time, and with a high proportion of cattle falling within the specifications for carcass weight, fat cover and meat quality.

Silage is one of the supplementary feeds that can be used to achieve production goals. It is suitable for all classes of cattle, including calves from three months old.

Full production feeding

Silage can be fed as the sole diet or with concentrates. It is suitable for use in large- scale or small, on-farm opportunity feedlots.

Temporary feedlotting may occur in paddocks where pasture availability is severely limited and represents only a small proportion, probably <10%, of total intake.

Drought feeding

Producers should always aim for high quality when conserving silage as a drought reserve. High-quality silage is cheaper to produce, on an energy basis and allows increased management flexibility.

Depending on the available reserves, silage can be used to maintain breeding stock and finish growing cattle for sale.

A feed budget should be prepared to determine the numbers of cattle that can be fed for maintenance or for production, and those which need to be sold because they cannot be adequately fed.

Silage made on-farm is a valuable source of high-quality roughage and is usually much cheaper than hay purchased during a drought. Having sufficient reserves of silage allows cattle to be fed in small ‘sacrifice’ paddocks, protecting the rest of the farm from overgrazing.

Supplementary feeding

There are a number of situations where silage can be used as a supplement to pasture, filling gaps in the quantity and/or quality of pasture available:

• Ensure adequate nutrition for cows prior to calving;
• Meet cow requirements during early lactation when nutritional demands are high (this can be critical in ensuring fertility and maintenance of the calving pattern, particularly in more marginal grazing areas);
• Maintain growth rates of weaners and young, growing cattle to meet market specifications for slaughter or feedlot entry; and
• Maintain heifer growth rates to ensure fertility, particularly in more marginal areas where poor growth rate may mean that heifers do not conceive until they are more than two years old.

Other strategic supplementary feeding

There are a number of other situations where full or supplementary feeding with silage can improve cattle management, production and health:

• Calves can be fed in holding yards at weaning. This is most effective when the calves have been fed silage while still with the cows.
• Silage can be fed to cattle as part of a pre-conditioning program, prior to feedlot entry.
• Silage supplementation will reduce the risk of bloat in cattle grazing lucerne or legume-dominant pastures.
• Silage supplementation will reduce the incidence of grass tetany in cattle grazing young, lush pastures.

Production benefits

Most beef enterprises have marked seasonal variation in pasture production and quality. Much of the surplus DM produced during the period of peak pasture growth is not utilised because stocking rates usually reflect the number of stock that can be carried over the whole year. Utilisation of the total annual production from a pasture can be as low as 30-40% of the potential.

Beef production per hectare may be increased if surplus, high-quality pasture is cut for silage, although this will depend on stocking rate (see Figure 1.4) and beef prices. Estimates of the potential beef production per tonne of forage and per hectare are provided for a range of pastures and crops in Table 1.5.

Integrating silage into a beef enterprise has a number of potential benefits:

One of the main options for silage use is to increase stocking rate — and production per hectare — without changing the production per head or the market specifications for the animals being sold. Producers can either increase the size of their breeding herd or increase the number of animals turned off from a steer-growing enterprise.

The other main option for silage use is to increase production per head, thereby increasing production per hectare. A higher proportion of the current turn-off can be finished for sale or slaughter, or turned off earlier and/or at higher weights, independent of prevailing pasture conditions.

This will improve the producer’s capacity to supply the target market. If the objective is to turn off animals at a younger age, this resulting reduction in the effective stocking rate will provide an opportunity to run more stock.

Some producers will choose a combination of the two options above.

Additional benefits

Within a beef enterprise, silage can also:

• Act as a pasture management tool, improving pasture productivity and composition, and reducing weed content (see Chapter 3);
• Reduce the reliance on purchased supplementary feeds (purchased hay can be low in quality and is often more expensive per unit of energy or protein fed than silage produced on-farm);
• Provide the supplementary feed that may be required to change calving time, allowing producers to target higher- value markets at alternative times of the year or improve reproduction rates (calving percentage); and provide producers with the flexibility to target cattle for alternative markets (e.g. heavy grass-fed steers for the Korean market, which is not feasible in many pasture-based enterprises in Australia).

Beef: determining the role for silage

1. Set clear production goals for the physical and financial components of the beef enterprise. Identify the areas that need change.

2. Assess the forage (pasture, crop, conserved forage) resources available on the farm:

• When will surplus forage be available for silage production?
• What silage quality can be achieved from the available forage?
• Will the quality/quantity match that required for the new production system?

3. Is silage the best strategy for providing the additional feed required for the changed production system?

4. Will silage use change turn-off times, allow access to higher prices, or incur extra costs? Will these need to be budgeted for in a cash flow assessment?

5. How will the new system influence overheads and labour requirements?

6. What is the impact on the cost per Kg beef produced from the farm, and how does this compare with beef prices — is it profitable?

Conclusion

Incorporating silage into a beef enterprise has the potential to increase farm profitability if the silage is of high quality and losses are kept to a minimum. A target ME content of 9.5-10 MJ/kg DM or higher is essential if high levels of beef production per tonne of silage, and per hectare, are to be achieved.

The two key areas where silage will have the most impact will be an improvement in production per head (improved compliance with market specification, achieved earlier) and an increase in stocking rate.