09 July 2020

Want 50kg more winter weight gain for no extra cost? Cut silage in May instead of June

Research conducted at Teagasc Grange has shown that cattle fed high quality 75% dry matter digestibility (DMD) silage gained almost 50kg additional live-weight over a 5 month winter compared to similar cattle fed 65% DMD silage. Joe Patton explains the results of this research.

Average silage quality for beef farms nationally remains at around 65% DMD however, with a typical range of 58 to 78% DMD. While average-type silage is suitable for dry suckler cows, farms feeding with growing cattle or calved cows over the winter stand to benefit from focussing more on quality for first cut crops.

What can make the difference for quality? Large gains in DMD are to be made by bringing cutting date forward into May, and taking out swards before stem and seed heads emerge.

This requires good management of soil fertility and fertilizer in spring to ensure nutrients are applied in good time at the right rates. Reseeded swards tend to grow faster and are easier to ensile at an earlier cutting date. It is always advised to test the standing crop for sugars and nitrate content around cutting date, rather than waiting for fertilizer Nitrogen to be used up based on application dates. Some farms may wish to wait into June to ‘bulk up’ first cuts but research has shown that this may actually reduce annual yield of feed due to reduced second cuts and less autumn grazing.

Feed is the single biggest cost on cattle farms and about 40% of feed cost in a typical system is due to silage. It is therefore very important that silage quality is managed in tandem with quantity. An industry shift to cutting silage in mid-late May for higher performance cattle is needed.