Dave will summarise some of the recent work at SRUC Dairy Research Centre, Crichton Royal Farm Dumfries. Two dairy farming systems were compared between 2003 and 2010 with cattle on high forage and a low forage system.
The enteric methane production from the cows on these systems was estimated and cattle on the high forage system produced approximately 25% more methane /litre of milk than the cows on the low forage system. A desk top study was also undertaken which showed that improved silage quality resulted in lower enteric methane production per litre of milk. The effect of soil compaction by machinery and cattle in the autumn on spring grass yield and nitrous oxide emissions has been investigated in an experiment funded by DairyCo.
The compaction treatments had an effect on N2O emissions with the mean tractor compacted plots showing the greater emissions compared to the trampled and control plots (24.5g ha-1 increase compared to the control over the growing season), especially after the first fertiliser application (14.9h ha-1 increase in emissions compared to the control). These experiments and the new dairy farming systems , including one with all feed grown on farm, will be discussed.