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Grass Production and Feed Efficiency

Grass Production and Feed Efficiency

Measurement of dry matter intake and feed conversion efficiency (FCE)

Assessing dry matter intakes is a key element for success. Measuring milk production, knowing how much cows are consuming in dry matter terms and predicting feed conversion efficiency will ensure that action can be taken to adjust the diet. The efficiency can be calculated by; expressing the energy corrected milk production as a function of dry matter intake. Ratios of 1.1-1.2 or less, are common in non-buffer feeding situations. FCE values of 1.2 –1.4 or more (more efficient) are achievable by feeding a balanced TMR besides grazing.

Grass growth

So far this year, according to AHDB data, grass growth has been more segmented compared to previous years; more than likely due to a sudden change of weather. Countries from the midlands have the highest growth over the UK.




Grass protein

Grass quality from this year’s AHDB figures seems normal and nicely follows the values of the previous year. As the crude protein rate is normally decreasing, farmers need to think to increase the protein level of the buffer diet.


AHDB sources show a big variation into the protein value of fresh grass. Mid June, it did vary 30% to as low as 15%.



InTouch customer data:

Across England, Scotland and Wales, data has been collected for April and May, looking at the grass DM intake VS. Feed Efficiency and cost.

April 2017

April was not a month where the amount of fresh grass in the diet was important. Farmers were saving the crop for their first cut silage, and the lack of rain made the growth very slow.

  FCE Milk kg/D Total intake Grass intake Margin over feed cost in £ Cost/litre


In pence




1.27 21.61 17.02 5.7 3.47 10.71



1.19 28.03 23.61 4 3.93 14.1

May 2017

Sun and rain were excellent during May, fresh grass intake shot up in most of the diets.

  FCE Milk kg/D Total intake Grass intake Margin over feed cost in £ Cost/litre


In pence




1.28 24.48 19.19 10 4.43 9.99



1.16 23.77 20.54 5 3.37 12.36

Grazing grass is a cheap way of producing milk, but can be an expensive one if not managed properly. With the data collected, we can see that there is a certain correlation between grass intake, feed efficiency and profit.

The use of well formulated grazing TMRs provides a much more considered route when optimisation of cow performance and feed utilisation are recognised as crucial to the financial viability of the business. It brings better opportunities to exploit the cheapness of grazed grass and optimise returns from higher yielding cows.