Treat silage as grazing by-product

Silage should be treated as a by-product of milking cow grazing, but this means finding contractors who want to work with customers, says New Zealand dairy consultant Peter Gaul.

“Cow silage is a by-product of grazing.

Our aim is to present the best feed to grazing cows at all times.

We want to train cows to eat consistently to residuals and manage any surplus to maintain pasture quality,” he said.

Mr Gaul told delegates at this year’s Pasture to Profit conference, Stafford, that a contractor who was customer focused would recognise what a grazing-focused milk producer was trying to achieve.

He recommended UK milk producers thought through the significance of paying more to cut surplus for silage, rather than shooting themselves in the foot by simply avoiding a higher charge.

“Ask your contractor how much it would cost to get him to drop cutting height.”

As consultant to Lincoln University Dairy Farm in New Zealand’s South Island, Mr Gaul said the farm operated a policy of taking light crops of silage after grazing.

“Silage dilutes diets and our aim is to avoid using it wherever possible.

We no longer feed it to milking cows in spring.

“We make baled silage from 3400-3600kg DM/ha of cover so that in 22 days’ time, pasture can be grazed again.

We don’t want to wait for a heavier cut to suit contractors.

We also ask them to cut it low, 3.5cm, to get paddocks ready for the next grazing.

“This means we need a flexible contractor who can do the job as soon as possible.

Removing surplus grass quickly is the key to quality pasture.

It costs more – 11c/kg DM instead of 9c/kg DM – but is worth it for quality.”

Eight cuts have been baled so far in the NZ milking season, averaging 12MJ of ME and 40% dry matter.

The only problem Mr Gaul reported was a high pH, which meant silage did not keep long and had to be used the same season.

But the policy appears to be paying off.

It grew more high quality grass.

Increasing stocking rates to use it had added NZ$200,000 (82,645) extra income in the first three years, said Mr Gaul.

“We added 300kg/ha milk solids at no extra cost, except a bit of management.

But we did not do better just because we grew more grass.

We estimate grass growth and measure what goes off the farm.

We use a rising plate meter weekly, cut and test grass and weigh all supplements fed,” he added.