Are you leaving milk solids behind?

Failing to provide dairy cows with grass at the optimum pre-grazing yield could be hitting the income potential on some dairy farms.

Joining James Dunne, Teagasc Dairy Specialist, on a recent episode of the Dairy Edge podcast, Senior Research Officer, Dr Michael Dineen touched on the important factors farmers need to bear in mind when balancing grass quality and quantity to maintain milk production throughout the summer months.

Central to the discussion was pre-grazing yield, with Dr Dineen outlining the role it plays in terms of grass quality and cow production. Previous studies, he explained, identified pre-grazing yields of 1,400-1,500kg DM/ha as the optimum when balancing both cow performance and pasture production.

Where pre-grazing yields exceed this point and push toward 2,000kg DM/ha and above, a common practice witnessed on some farms recording covers through PastureBase Ireland, grass quality falls, digestibility lowers due to the inclusion of more stem and dead material, the cow’s intake potential is limited, and this ultimately leads to a reduction in milk solids production.

Citing studies from Dr Michael O’Donovan’s team in the Teagasc Grassland Department in Moorepark, Dr Dineen explained how moving from the optimal pre-grazing yield of 1,500kg DM/ha to covers of 2,000kg DM/ha and above impact on milk solids production.

“They typically seen across the lactation a reduction in performance when you go past the 1,500kg DM/ha [to the 2,000kg DM/ha covers] and it would equate to just under 0.1kg/cow/day of milk solids. That can accumulate up to be a lot of milk solids and it’s quite consistent when we look at a couple of different studies, you do lose animal performance.”

Running from the April to November period and encompassing a 120-day period, Dr Dineen also provided an example as to how this reduction in performance as found in these studies would affect the potential income of a 100-cow herd. Using a guide price of €5/kg of milk solids, he noted that it can equate to a reduction in income of €6,000-9,000 due to poorer grassland management practices.

“It’s quite a large number when we think about it. It’s relatively a free thing to achieve. It does take labour, input, thought and effort, but it doesn’t cost a huge amount to maintain that good grassland management,” he added.

Listen to the full episode of the Dairy Edge podcast below where Dr Dineen also provides insights into grass allocations, post-grazing sward heights and concentrate supplementation rates:

More episodes from the Dairy Edge podcast

Also read: Don’t obsess about peak milk, obsess about grass quality to drive milk solids