Profitable winter-milk systems rely on the availability of high-quality silage, with 75-80 dry matter digestibility (DMD) targeted to lessen the requirement for concentrate feed over the winter months, Teagasc has said.
Advisor on the Teagasc/Aurivo Joint Programme, John McCabe pointed to a number of cutting dates farmers should aim for to ensure the production of quality silage for their winter-milk herds.
The aim is to produce high yields of very digestible silage that is well preserved, McCabe said.
As the cutting date moves later into May, more fibre will be present on account of the additional bulk, second-cut yields will be reduced, and an expensive winter diet for cows will follow, he said.
Winter-milk silage
Alternatively, McCabe said that where an early May cutting date is achieved, less fibre will be present in the silage, a heavier second-cut will be obtained, and a cheaper winter diet based on a silage capable of supporting higher intakes will result.
“The more fibre that you push into your silage by delaying it out into May, the less the cow is going to be able to eat.
“We want to reduce the amount of fibre, the amount of stem, because we want the cows to eat more silage and we want the cows to eat better silage,” McCabe said.
After a challenging spring, McCabe pointed to a cutting date between May 5-10 as the “optimum” for silage for winter-milk systems.
He noted that this will allow sufficient time to achieve high yields in the second cut in late June. However, this will vary depending on the level of grazing achieved on farm this spring, the advisor said.
There is ground that has been un-grazed since the end of September or the start of October which, he said, needs to be gone by May 5 to feed a winter-milk cow in a “profitable way”.
If these grounds weren’t to be cut by early May, the Teagasc/Aurivo Joint Programme advisor said that the silage could drop from good quality to poor quality in the space of a week.
“If it was grazed bare in autumn or spring, we would say it needs to be cut before May 12, and if it is grazed recently, it needs to be cut before May 18-20 for a winter-milk cow,” McCabe said.