THIS year’s Scottish silage crops are of high quality, but farmers must calculate stocks and ration to deal with the shortfall.

The advice follows lab tests by SAC Consulting, part of Scotland’s Rural College, which found silage contained a much higher dry matter percentage and more energy, with good fermentation characteristics, compared to 2017.

This means animals will want to eat more silage this winter, but that if they are fed in the same amounts as in wetter years, it will exacerbate the shortfall.

The average dry matter of silage in 2018 is 35% – up 12% on last year. This is particularly significant this year because, although there may be less on a fresh weight basis, on a dry matter basis there is actually more.

For example, a 600kg bale at 35% dry matter equates to 210kg dry matter compared to just 138kg for a bale with just 23% dry matter.

Using the silage analysis, nutritionists have predicted how much of it an animal will eat when offered ad lib – its Silage Intake Potential.

This year’s silage results suggest cattle voluntary intakes could amount to 15% more silage dry matter than last year.

For a 650kg dry spring calving beef cow, this would result in over-eating energy and protein so she gains weight over the winter, resulting in difficulty at calving. It would also mean eating 40% more fresh weight of silage than she needs, using up supplies quicker.

Ruminant nutritionist at SAC Consulting, Mary McDowell, said: “To avoid wasted silage and poorer cow performance, it has never been more important to get silages analysed, get the stocks available calculated, and get appropriate rations planned to ensure target performance is achieved. This will mean that scarce forage supplies are effectively utilised to minimise costs over the winter.

“When restricting silage intake, it’s also vital to ensure plenty trough space is available and that younger, shyer or thin cows are managed separately to avoid them being bullied away from feed.”