Galway dairy farmer Eamonn Connaughton was the keynote speaker at the Teagasc once-a-day milking conference held online last week.

Eamonn switched to once-a-day (OAD) milking in 2018 and is currently milking 140 cows producing 410kg MS/cow, with a six week calving rate of almost 90% and profits comparable to his twice-a-day milking days.

The loss of leased land close to the parlour in 2018 nudged Eamonn into OAD milking for the first time.

Prior to this, Eamonn had grown the herd from 110 cows to 160 cows, but when he lost the land close to the parlour, the farm became more elongated, making regular long walks of up to 2.5km and multiple road crossings inevitable.

Having attended a previous OAD milking conference, Eamonn weighed up his options and considered that he would be able to milk off all his farm, even the areas furthest away that were previously used for rearing heifers, if he went OAD. Because of the distance and the fact that he had to cross three roads to access this land, milking twice-a-day wouldn’t be feasible.

Eamonn found 2018 challenging on a number of fronts, not least the bad weather in spring, losing the land and then the summer drought.

He says he kept the 160 Jersey crossbred cows for the first year, as he was prepared to have to cull cows not suited to OAD. However, as he didn’t know which cows these would be he adopted a wait-and-see approach, which meant running a high stocking rate of 3 cows/ha. As a result, a lot of extra winter feed had to be purchased in due to the drought.

Even with a 14 unit parlour and 10 rows, milkings are taking 2.5 hours at peak so Eamonn is considering increasing the size of the parlour in the future to accommodate more units. He says OAD is not a viable long-term option for those looking to milk a lot of cows, because the morning milking takes much longer than if milking twice-a-day.

/ Donal O' Leary

Prior to going OAD, the herd was milking 454kg MS/cow in 2017. This dropped to 374kg MS/cow in 2018, a 17% reduction.

“I had lost about one-third of the farm, so I accepted there had to be a reduction in income.

“I had attended the OAD conference that year and heard about the expected 20% drop in production. I was quite happy, when comparing myself to previous years or to my discussion group, that I hadn’t dropped more than what would be expected when on once-a-day,” Eamonn says.

Milk solids yield has been increasing year on year, and the herd hit 410kg MS/cow in 2021, with an average SCC of 178,000.

Eamonn says he expects that in three or four years’ time, he will be back at 450kg MS/cow while remaining on OAD milking. He says he hasn’t done much culling, even on those that go dry in August. Instead, he doesn’t breed them to dairy and will cull them when their time comes.

On SCC, while he’s happy with an average of 178,000, he says it’s at a dangerous point and will need to be managed carefully to avoid it ballooning. He didn’t milk record in 2020, but did it last year and will record again early this lactation. This will allow him to take action on cows that haven’t been cured.

In terms of profit, according to profit monitor data, the farm made a net margin per cow of €702, or €1,847/ha in 2020. This is before capital repayments, tax and Eamonn’s own drawings. Heifers are contract reared since 2018, so all the 54ha farm is considered milking platform.

Prior to going OAD, the farm made a net margin of €954/cow or €1,955/ha in 2017, which was a better milk price year than 2020.

Cost control has always been good on the Connaughton farm, with variable costs of €701/cow and fixed costs of €361/cow in 2020.

“Simple is often best I find. A lot of people complicate their systems for no particular reason and they end up spending more money as a result. Whereas if you keep it very simple and get the cows to grass, harvest the grass and then harvest the milk, that’s all you have to farm in a very profitable way,” Eamonn says.

Financially, he says he’s no worse off now than when he was on twice-a-day milking.

Back then, he had more labour in the system and lease payments. With that gone, he says his bottom line hasn’t changed much.

Teagasc researcher Emer Kennedy gave an update on the once-a-day research happening at Moorepark. OAD trials have been going on since 2019 and the most recent study looked at the impact of short-term OAD milking.

This involves milking OAD for three weeks at the start of calving in the spring and for the last nine weeks in the autumn before drying off.

In total, cows were on OAD milking for a total of 84 days and went on OAD from 4 October until dry off in early December.

Emer found a 7% reduction in milk solids yield for the cows on the short-term OAD milking compared to those on twice-a-day for the full lactation.

Milk solids production averaged 504kg MS/cow for the herd on twice-a-day all season and it was 469kg MS/cow for the herd on the short-term OAD. During the period of OAD in spring, daily milk solids yield reduced by 11%.

There was no impact on peak milk production and as soon as cows went back on twice-a-day milking in spring, their milk yield increased in line with those on twice-a-day milking.

Emer said that in a farm situation, the impact of OAD in spring will be less, because most cows in the herd will be on OAD for a shorter period than three weeks.

For example, cows calving on day 11 will only be milked OAD for 10 days before going back to twice-a-day milking. However on the trial, all cows were milked OAD for three weeks.

Milk solids yield dropped more in the autumn, with a 23% reduction in milk solids yield per cow for those milked OAD for the last nine weeks of lactation compared to twice-a-day milking.

Previous Teagasc research has found a faster drop in milk yield when cows are milked OAD in the autumn. Total lactation length was the same for both treatments at 287 days and cows remained at grass until the end of the trial.

Emer Kennedy, Teagasc, speaking at the Positive Farmers Conference in Clonmel. / Donal O'Leary

“The somatic cell count increased with cows on once-a-day. We’re suggesting that you’d need a cell count of less than 100,000 before you change over [to OAD in the autumn]. You can possibly dry off any high cell count cows before switching to once-a-day to facilitate this,” Emer says.

On average over the last three years, the herd on fulltime OAD milking has seen a 21% reduction in milk solids yield compared to their twice-a-day compatriots.

Interestingly, there has been no recovery in milk solids yield by year three of OAD in Moorepark, with cows consistently producing about 20% less each year.

In terms of cow type, Emer said the cows on the trial were not selected specifically for OAD, but are all high-EBI with an average EBI of €214, with one-third of the herd Jersey crossbred.

She stressed the importance of good grassland management in OAD systems, saying the target in Moorepark is to graze covers at between 1,400kg and 1,600kg and to achieve a good clean out.

She also said providing grass in the diet for as long as possible in the autumn is also important.