DAIRY FARM SYSTEMS FOR GOOD ECONOMIC AND

ENVIRONMENTAL PERFORMANCE

VICKI BURGGRAAF1

IRIS VOGELER1

PIERRE BEUKES2

DAVE CLARK2

1 AGRESEARCH LTD 2 DAIRYNZ

NEW ZEALAND $$$$

How can we farm profitably with a low environmental footprint?

48% NZ GREENHOUSE GAS

OVERVIEW

Model dairy farm with increased efficiency

1. Dairy intensification in NZ2. Causes of environmental issues3. Strategies to reduce negative impacts4. Model effects on production, profit, GHG, N leaching5. Effects of year to year climate variability

DAIRY INTENSIFICATION

DAIRY INTENSIFICATION

Since 1990:• 78% increase in dairy land area• 20% increase in SR (cows/ha)• 85% increase in total no. cows

DAIRY INTENSIFICATION

Since 1990:• 78% increase in dairy land area• 20% increase in SR (cows/ha)• 85% increase in total no. cows

Increased feed intake per hectare• Pasture utilisation• Increased use of nitrogen fertiliser• Increased use of bought-in supplements

DAIRY INTENSIFICATION

Since 1990:• 78% increase in dairy land area• 20% increase in SR (cows/ha)• 85% increase in total no. cows

Increased feed intake per hectare• Pasture utilisation• Increased use of nitrogen fertiliser• Increased use of bought-in supplements

MILK PRODUCTION INCREASED 130%

PROBLEMS OF INTENSIFICATIONMore cows and high N feed: More N fertiliser:

methane

nitrate leached

URINE

nitrous oxide

N fert

REDUCING THE IMPACT1. Fewer animals2. Efficient animals3. Stand-off pasture – less nutrient loss4. Low N feed supplements5. Less N fert use, nitrification inhibitor

Small effects in isolation

STACKED TECHNOLOGIES

PARAMETER BASE FARM EFFICIENT FARMStocking rate (cows/ha) 3.0 2.6Cow genetic merit (BW) 60 120Replacement rate 23% 17%Feed Pasture Pasture + maize grain Stand off pasture No YesEffluent area (% of farm)

20 24

N fertiliser area 180 kg N/ha 50 kg N/ha/yr + nitrification inhibitor

MODELLED DAIRY FARMS

WAIKATO CLIMATE EFFECTS

• Rainfall 1100 mm, temperate climate

• Summer rain: more pasture → milk, profit

• Winter rain: nitrate leaching, nitrous oxide

• Base vs efficient farm:

Low Medium High production Dry Average Wet summer

945 mm 1056 mm 1197 mm rain/yr

WAIKATO SUMMER RAINFALL

Dec Jan Feb Mar0

50

100

150

200

2502003/04

2004/05

2007/08

mm

WHOLE FARM MODEL Pasture production Grain fed Milk production Profit Methane Urinary N

APSIM Nitrate leaching

OVERSEER Total GHG

• Management

• Daily climate

• Management• Annual

rainfall

MODELLING FRAMEWORK

PASTURE PRODUCTION

Dry Average Wet0

5

10

15

20 BaseEfficient

t DM

/ha/

year

TOTAL FEED INTAKE

Dry Average Wet02468

101214

BaseEfficient

t DM

/ha/

year

8% 4% 1% maize grain

MILK PRODUCTION

Dry Average Wet0

200400600800

100012001400

BaseEfficient

kg M

S/ha

OPERATING PROFIT

Dry Average Wet0

50010001500200025003000350040004500

BaseEfficient

$/ha

METHANE EMISSIONS

Dry Average Wet012345678

BaseEfficient

t CO

2 eq

/ha/

yr

TOTAL GHG EMISSIONS

Dry Average Wet0

2

4

6

8

10

12

BaseEfficient

t CO

2 eq

/ha/

yr

N LEACHING

Dry Average Wet0

1020304050607080 Base

Efficient

kg N

/ha/

year

CONCLUSIONSEfficient farm systems:

•Milk production ↑ 8-17%•Profitability ↑ 18-80%•GHG ↓ 23-27%•N leaching ↓ 30-50%

Impact of climate:•Efficient always best•Variability high for leaching, profit

This research was funded by: