P1252108908sgWaq

1
The Development of Future Grazing
Systems- Grassland Management and Fertilizer Use
on Intensive Dairy Farms
B. Horan, J. Coleman, B. McCarthy and A. Brennan
Teagasc Moorepark, Fermoy, Co. Cork.
2
Overview

• A change in systems objective
• Appropriate management practice
• Performance results
• Fertiliser Strategy
• Conclusions to date

3
A Change in Research Objective

• Currently have a very good production system

Current Target
NFS
0.15
0.22
Cost per litre excl. labour _at_ 30 c/l ()
0.09
Profit per litre excl. labour _at_ 30 c/l ()
0.23
1,030
Profit per ha ()
2,500
1.77
Profit per kg milk solids ()
2.05
NFS, 2007
4
Milk Price Volatility

• Milk Price will fluctuate between 22 and 40 c/l
  in future

• As a low cost producer Ireland must develop
  systems that will be profitable each year, can
  cope with milk price volatility and allow for
  expansion opportunities

5
A Change in Objective

• To maximise profit per hectare of farm land and
  expand overall system productivity for a post
  milk quota milk production environment
• by

1. developing grazing techniques that maximise
   pasture production and feed value
2. increasing stocking density to maximise feed
   utilisation
3. generating a dairy herd that is both productive
   and highly feed efficient
4. employing supplementation and nutrient use
   practices that facilitate improved environmental
   consequence

6
Appropriate Management Practice..Growing
Harvesting More Grass
Irish dairy farms must deliver sufficient feed to
expand herd size without increasing exposure to
high cost external nutrient sources.
7
Grazing Technology Basic Principles

• Measurement and informed decision making
• Extended grazing season based on feed budget
  (280 days)
• Good roadways / paddock access/ water
  infrastructure
• Supplements included when grass supply is
  limited/ growth reduced

• Excellent soil fertility
• On/off grazing to avoid paddock damage and
  increase grazing efficiency

Curtins Feed Budget
8
Growing more Grass

• Avoid poaching and topping
• Maximise leaf production minimise decay
• Create a green leafy base
• Increase nutrient use efficiency

9
Growing more grass - The LUDF Model
Growth is the product of light, nutrients and
management
2001 - 2005
Pregrazing height 12 13 cm
Residual 6 cm
Growth 12.5 tons /ha
Avoid leaf death Create green leafy base
10
Increase Leaf Production

• Leaf production is maximized by grazing to 3.5cm
  residual height

Bircham and Hodgson (1983)
11
Creating and Maintaining a Green leafy Based Sward
12
(No Transcript)
13
Grass Growth Results
2008 15,964 kg DM/ha
tons DM/ha/yr

• Large paddock to paddock variation unexplained
  by soil fertility
• Potential to grow 18 tons on older swards

• Some underperforming reseeds
• - paddock size / residency time
• - increased requirement for fertiliser

14
Harvesting more Energy

• Higher stocking rates and earlier calving based
  on feed budget

15
System Performance
2001-05 2007 2008
Stocking rate (LU/ha) 2.5 2.65 2.89
Mean calving date 10/2 20/2 24/2
Pre-grazing yield (kg DM/ha) 2,200 1,440 1,390
Residual grazing height (cm) 6.2 5.1 3.5

Concentrate (kg/cow) 350 190 275
Fertilizer (kg N/ha) 300 305 246
Grass growth (t DM/ha/yr) 12.5 14.7 16.0

Milk Solids (kg/cow) (kg/ha) 500 1,250 478 1,254 420 1,214

Surplus feed (t DM/ha) - 1.7 1.6
16
Fertiliser Strategy

• P and K requirements based on an annual soil test

• N is still fundamentally a cheap supplement if
  use efficiently
• Objectives at high SR to maximise efficiency of
  250kg N/ ha
• N savings based on grassland measurement and
  slurry use
• Increase dilute slurry use in January-March
• 33 of area receiving 2,500 gals./ac in January
• 15 of area receiving 2,500 gals./ac in March
• Mid-season fertiliser usage based on grass supply
  targets
• Reduced to 10 units of CAN when growth allows

17
Fertiliser Strategy
Month Kg N/ha Month Kg N/ha
Jan/Feb 21 July 21
March 36 August 21
April 28 September 33
May 43
June 43 Total 246
All area included until April 5th, 60 area
included from April 6th to May 25th, 75 area
included from May 26th to July 15th and all area
subsequently
18
Nutrient Budgeting
2001-2005 2008 Future?
Stocking rate (LU/ha) 2.5 2.82 3.3
Grazing season (days) 275 285 285
Grass (kg DM/cow) 4,040 3,500 3,500
Concentrate (kg/cow) 350 175 250

Fertilizer (kg N/ha) 300 250 250

Milk yield (kg/cow) 6,300 5,500 5,500
Milk Protein (g/100g) 3.55 3.60 3.60

Total N import (kg/ha) 320 270 275
Total N export (kg/ha) 94 96 111
Total N surplus (kg/ha) 226 177 164
N-use efficiency () 29 35 41
Estimates based on available information
October 2008
19
Developments in Irish Grazing Systems

• Growth potential of pastures has been
  underestimated 18 tons

• Stocking rates must match growth 3.3 cows per
  hectare
• Management practice can increase plant growth
• Residual grazing height of 3.5 to 4 cm
• Shorter rotations with 8 9 cm pre-grazing
  height
• Increased use of dilute slurry in spring

20
Preliminary Conclusions

• Profit potential of well run pasture-based
  systems is high

21
Teagasc Moorepark wish to acknowledge Dairy Levy
Funding Weekly updates on Teagasc farms
available at http//www.agresearch.teagasc.ie/mo
orepark