Kim Robinson

Northland Dairy Development Trust (NDDT) is conducting another three-year trial investigating the use of palm kernel extract and other supplements on farm production, profitability and environmental measures.

This project compares a farm that does not import any supplement (pasture only farm) with a farm that only imports palm kernel (PKE only farm) and a farm that imports palm kernel and other supplements (PKE plus farm).

The trial came about as a result of farmers asking whether it was profitable to import other feeds such as DDG to boost production when milk fat evaluation index (FEI) is limiting palm kernel use.

Palm Kernel is fed on the PKE only and PKE plus farms when pasture supply is limiting. Other supplements are fed to the PKE plus farm when FEI levels indicate no further palm kernel can be fed.

The first season of this project is now complete. Climatic conditions were considered average with some challenge from wet conditions during early spring and dry conditions during late summer/ autumn. Feeding of palm kernel was constrained by milk FEI during summer and autumn, but not during spring.

Comparing milk production and supplementation between farms provides a calculation of the response rate to supplements. This shows a response of 100g milksolids (MS)/kg drymatter palm kernel fed on the PKE only farm and a response rate of 94g MS/kg palm kernel, dried distillers’ grain (DDG) and baleage fed on the PKE plus farm.

Monitoring of managers’ stress levels associated with each farm has indicated that the PKE only farm had higher stress than the others during summer/autumn when palm kernel feeding was limited by milk FEI.

Preliminary environmental modelling indicates the pasture only farm has considerably lower carbon emissions than the other farms.

The calculation of operating profit takes into account labour and other costs associated with each farm. The purchase of palm kernel at $268/ tonne average (landed) was profitable at the $6.35 milk price received.

The cost of the extra milk produced was $5.33/kg MS. However, the drop in profit on the PKE plus farm showed that the extra milk produced from DDG ($540/t in silo) and baleage ($80/b delivered) cost $10.51 to produce.

These results have confirmed that higher production per ha does not necessarily lead to higher profit, and farmers should be careful when buying extra supplement to increase production.

Full results of the trial are on and fortnightly updates are posted on Facebook.


NDDT is conducting a plot trial this spring to measure the pasture responses to nitrogen, sulphur and potash combinations. This is to support farmer decisions around the use of Ammo and Urea-Potash fertilisers in spring to increase pasture growth above straight urea. The plots will cover a variety of soil types around Northland and results will be published in December.

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