Silage Dry Matter Guessing Game

Silage Dry Matter Guessing Game

Tuesday, November 3, 2009

When visitors to the Dairy Event and Livestock Show, including many consultants, were challenged to estimate the dry matter of six grass silage samples, they proved a proper analysis is worth paying for.

Sciantec Analytical Services only intended the challenge as a bit of fun. But comparing the actual DM content as analysed using standard wet chemistry in the laboratory with the visitor estimates underlines just how difficult assessing DM content can be," says Linda Forbes, one of company's business development managers.

 "Many of those who participated have years of experience and even they found it difficult, especially when it came to estimating the higher DM silages," she adds.

She explains the average estimates for the two highest DM silages were just 49% and 37.5%, but the actual DM values were 61.3% and 55.2%, respectively. In both cases, diet contribution from silage was effectively undervalued which could have led to inflated feed bills.

At the lower end, average estimates were much closer to the actual figures. However, averaging hides a wide variation in individual estimates, as the sample with an actual DM of 27.2% was estimated at levels between a maximum of 60% and a minimum of 17%.

The most reliable way of valuing the nutritional contribution from silage is to test the sample. Silage analysis costs just £13.50.


BGS Members BGS is a membership organisation which acts as a communication forum, through events and publications, for the profitable and sustainable use of grass and forage.

Local Societies

BGS Members Use our Local Society directory to locate your nearest societies, information resources and experts on grassland farming and foraging.