A dry May has helped Stafford-based James and Lucy Muir’s dairy herd get back on top of grazing at Hopton, having taken out 73 hectares (180 acres) for first cut silage.
Despite focusing the family-owned 450-strong New Zealand spring-calving herd on making the most of grazed grass, James and Lucy Muir believe there is a balance to be struck.
Mr Muir says: “Dare I say it, but the dry spell played in our favour. Grass growth raced ahead of our ability to utilise it during spring, but by late May, growth was 79kg DM/ha with just 11mm of rainfall for the month, compared to 134kg DM/ha with 73mm of rain last year.
“We have been able to take about 1,500 tonnes of good quality dry silage into the clamp which is the herd’s core winter feed.
“Last week, silage aftermaths had 4,000 gallons/acre of dirty water applied from our lagoons and a top dressing of 40kg/ha of nitrogen.
“Once recovered, the herd will move on to these paddocks freeing up others in the original 19-day rotation to be closed for second cut silage. If growth continues at pace, the amount of fertiliser applied will be halved.”
Peak milk production was achieved on May 1 at 30 litres/cow and is now slowly tailing off at about 27 litres/head at 4.14 per cent butterfat and 3.41 per cent protein. This was down slightly on May 2016 figures of 4.35 per cent and 3.50 per cent, respectively, due to drier conditions.
The decision was taken earlier this year to keep feeding 2kg/cow/day of concentrate in the parlour, despite surplus grass being available.
Mr Muir says: “The herd benefits from minerals in the cake, which reduced cases of grass staggers seen this spring. With 400 cows at milk, an alternative would have been to put minerals in drinking water, which would be more costly and complex in the long run.”
The plan is to keep monitoring grass growth rate twice/week through summer, allotting grazing according to needs and best use of available grass.
The herd will still access fresh grazing after each milking, but more mature paddocks set aside for second cut silage, 23ha (57 acres) to date, can be brought back into the rotation should growth rate tail off.
Mr Muir says: “Our average cover in late May was 2,437kg DM/ha, so we are not short, but it is all about managing the resource.
“Fortunately, having historic data from previous years helps tailor grazing plans on a day-by-day basis.
“A 24-acre area has been reseeded with a mix of AberMagic and AberChoice at 15kg seed/acre. Both are high sugar grasses and we hope to turn it around in eight or nine weeks, allowing youngstock to graze it lightly to encourage tillering. Once recovered, it will be included as part of the rotation.”
All AI service work will be finished shortly and a pedigree Hereford sweeper bull will go in to complete a 12-week service period.
Mr Muir says: “It went reasonably well. I had a target of 90 per cent to be served within a 21-day period and we achieved 81 per cent.”