‘Aim to maintain the lactation curve for the remainder of the year’

Despite the shortage of grass on many farms – as a result of drought conditions – dairy farmers must aim to maintain the lactation curve of their dairy cows for the remainder of the year, Glanbia’s Martin Ryan said.

Giving an example of a 100-cow herd, with a mean calving date of mid-March, Ryan said the difference between a 2% yield fall-off per week and a 3% fall-off per week between here and the end of lactation is 50,000L.

“Clearly there’s a strong reason to try and hold the lactation curve as best we can. Whatever length this current drought situation holds, we’ve several months afterwards which we will suffer income wise if we don’t try to hold milk yields.

“Normally at this time of year, cows would consume 18kg of dry matter; 2kg might be going in at the parlour and 16kg would be grass.

Where we are short 25-30% of grass – and everywhere is gone beyond that now – you’re looking firstly at feeding 6kg in the parlour.

“Historically, we might have said a couple of kilograms of meal and straights would have sorted that out. But on many farms, they’re well short of at least 50% grass and in some cases a good bit more than that.

“What we really need to do there is to go to 6kg in the parlour and add 4-5kg of soya hulls. When we get to here, that means that half of your total dry matter intake would be in the form of a concentrate-type material.

“If you’re passing that point, you definitely need to get some long fibre into the diet to get the rumen working,” the Glanbia nutritionist said at the recent Kildalton Open Source Sustainable Dairy Farm Open Day.

Martin noted that might be in the form of bales and a small number of kilograms will actually do the trick.

“It’s really then about how much grass do you have to cut back in terms of demand in that scenario.

We’d normally be saying to open silage, but the problem we have today is that we don’t have enough. Any silage we are going to use now is going to have to be replaced for next winter.

“It’s better off to hold what we can here and maybe even graze what silage ground we can if the covers are suitable to bridge the gap.”

The Glanbia representative also commented that there will be some scenarios where farmers will use alfalfa or haylage to provide the cows with long fibre.

“Its real purpose is to actually hold the diet together in terms of keeping the rumen right, digestion right and keeping the lactation right.”