Taking stock of forage

Maximising output from forage depends on many factors. Objectives will vary from farm to farm, with some focussing on output per animal and others on the output per hectare. Stocking rates will have a significant impact.

Key factors include not only having enough forage but the correct balance, which should be related to production objectives. For example, milk contracts favouring milk protein will benefit from higher maize silage inclusions, but these rations need supplementing with adequate fibre levels. In these cases, it may be worth cutting silage a little later to produce a higher fibre crop to help reduce purchased straw costs. Similarly, higher maize inclusion rations need adequate protein, so Maxammon (urea) treatment of grain and wholecrop can help to save on purchased protein costs. Table 1 shows possible forage alternatives and how these rations might be balanced for this coming winter (options one to three).

2. Maize silage utilisation

The cow will be able utilise maize silage much more efficiently if it’s left in the clamp for a few months after harvesting - ideally until the new year. So, what can be done to facilitate this? Firstly, clamp space availability needs to be considered - something which is commonly a problem. If there’s no old season maize silage left, consider wholecrop as a supplementary forage for the late autumn/early winter to ‘buy’ time. Alternatively, fodder beet can supply the additional fermentable energy to allow the new season maize to ferment. Rations can also be supplemented with maize grain if required to maintain starch levels. 

3. Prioritising straw to specific groups

Over the last winter, straw has been both expensive and scarce. Straw is important in supporting structural fibre in many rations, especially where butterfat is important. It will also help milk from forage by supporting good rumen health. Straw is also crucial in many dry cow rations. It offers low energy, bulk rumen fill with a low Dietary Cation Anion Balance (DCAB) value to help manage milk fever. Wherever possible, good straw should be prioritised for dry cows. If additional fibre is needed for lactating rations, consider making specific high fibre silage, by cutting a few days later than normal. If straw is not available for dry cows, make specific dry silage or haylage. Inherently, this silage should have reduced fertiliser and slurry applications (especially potash) to reduce the DCAB value and should be cut at an advanced stage to achieve the high fibre, low density crop.

4. Forage consistency

Maintaining silage consistency throughout the year is very important. Cows prefer a consistent ration and mid-winter ration changes need to be minimised. Forward planning in the summer, both in cropping and ensiling can help. It’s quite common to see milk production and quality decline when rations change from entirely first cut to subsequent cuts. Ask yourself if pits can be layered/arranged so that a consistent forage is presented through most of the winter.

Aiming to produce the best silage possible and understanding what stocks you have on farm is also important. Silage quality can vary hugely between farms (see Table 2). Assuming 12kg of forage dry matter intake, the difference in potential milk output between these extreme silages is over 5 litres per cow; effectively saving or costing 2kg of concentrates (36 tonnes over a winter for 100 cows).

That said, realistically, the biggest challenge will come from subtle changes through the clamp. Frequently, dry matters vary (not least with rainfall affecting surface dry matter), along with other parameters, often affecting rumen stability and consistency. Forage consistency should be a key goal.

Summary

In starting to consider next winter’s rations, contemplate objectives; these will be unique to each farm. Traditionally these will have included yield, product quality and of course cost, but increasingly sustainability and environmental aspects are becoming prevalent. Mole Valley Farmers’ Precision Nutrition can now help assess these factors