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Pasture Growth

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Date

 

Pasture growth rates was measured on the 17th May and were estimated to average 38 kgDM/Ha/day.

This was above average (24 kgDM/ha) for this time of year.

Simple feed demand vs feed supply calculation

Stocking rate (cows/ha) x intake from pasture (KgDM/cow/day) = target feed demand offered (KgDM/ha/day)

If we want to be able to fully feed the cows their current energy demands from pasture only then our feed demand is currently;

2.3 X 17.5kgDM = 40 kgDM/Ha/day. 

Pasture Grown season to date (from 1/6/15) is 13556 kgDM/Ha, this is 285 kgDM/Ha below last season and 336 kgDM above the long term average at SDF.

Total pasture grown for the 14/15 season is 15574kgsDM/Ha; this is 1927kgsDM/Ha less than the 13/14 season and 744kgsDM/Ha ahead of the 8-year average for SDF.

The accumulated total DM grown/ha to date for last 3 seasons is shown below. The long-term average growth per ha for SDF is 14.83 tons DM per year.

 

Discussions within the management team around mowing, either pre or post grazing centre around the following principles:

- Pre mow paddocks that have seed head present and are at least 100-200KgDM/ha above pre grazing requirement

- Those paddocks that are deemed to be less than 10-15% seed head and within the pre graze requirement are to be left for the cows to graze - this is one of the checks to ensure residuals are in the optimum range of 1550 -1650KgDM/ha from grazing with the cows. Once a mower is used the residual is set and it can take away one of your measures to check correct intakes are being achieved

- With the warmer weather and wilting factor we are aiming to pre mow as the cows enter the paddock or as near to, this ensures ME doesn't decline due to plant respiration and also maintain moisture conetent for the cows

- Ensure the blades are sharp for a clean cut rather than ripping / tearing the pasture for even regrowth and to avoid patches or lines of seed head regrowth

Click HERE for some practical pointers around mowing strategies to think about within your system.

 

Two pre grazing herbage samples were taken this past week to check pasture quality. Both paddocks were grazed by cows and not pre mown.

Looking at the two herbage samples pasture quality is being maintanied with MjME/KgDM showing 12.2 and 12.6 respectively.

SDF Pasture Analysis1 

SDF Pasture Analysis2

Refering to Dairy NZ Facts & Figures Page 14  provides an outline of the nutritional requirements at this stage of lactation as follows

% of the diet required

Protein % - 20%

Fibre % (NDF minimum) - 35%

Fat % - 3%