Purchasing forage, especially round bale silage, is very similar to purchasing lucky bags; you never know what you’re going to get. Its feed value also needs to be taken into account. As silage gets expensive, there may be more value in feeding concentrates and minimum forage. The best way to compare costs is to compare feeds on a dry matter basis or a UFL basis to get a fair comparison.

For example, purchasing very wet silage just means you’re paying to haul water. Low dry matter feeds need to be converted to a dry matter value to get a good comparison.

The UFL value of a feed is another word for the energy value of a feed. One UFL is the equivalent of 1kg of air-dried barley. Energy is required for maintenance, milk production, body weight gain and pregnancy.

Table 1 gives an indication of the value of purchased silage. You will need to make sure you have 50% of the diet as forage feed for winter months. One tonne of concentrates will replace 6t of silage. This calculation is based on 68DMD silage and UFL at 0.75. Concentrate UFL is based at 0.9 UFL.

As you can see from Table 1, if you are able to buy your concentrate ration at €280, you shouldn’t be paying any more than €47/t fresh weight for purchased silage or €37.60 for an 800kg bale of silage. If you are able to buy your ration at €250/t, the equivalent value of silage drops to €41/t or €32.80 for a 800kg round bale of silage.