Dried manure solids as a bedding material for dairy cows

THERE appears to be increasing interest among UK dairy farmers in the use of dried manure solids (DMS or 'green bedding') as an alternative bedding material for dairy cows, either on top of mattresses or mats, or as deep bedding in cubicle systems.

The practice has seen use in the USA and in some European countries for several years and has been recently adopted by a small number of units in the UK. Several types of DMS exist depending on the method of production and it is important to recognise that there can be large differences between these in terms of dry matter percentage, organic matter percentage and bacterial counts.

Probably the simplest method of DMS production (and likely to be the most common currently in the UK) is to pass slurry through an industrial screw press separator to achieve solids with a dry matter of between 35 per cent and 40 per cent, which are then applied 'fresh' to cubicle beds, on the same day as they are separated. Other methods of DMS production involve composting the separated solids in piles or windrows (a common system in the USA), composting the separated solids in a heated drum at approximately 700°C...