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Pastoral 21 Next Generation Dairy Systems was a five-year farming programme focusing on lifting dairy production while minimising nutrient loss. The programme set up farmlets in four regions - Southland, Canterbury, Manawatu, and Waikato - targeting region-specific challenges. The key strategies involved reducing nitrogen inputs, capturing urine during high-risk periods, and safeguarding wet soils to minimise nutrient runoff. They also aimed for efficient milk production using optimal pasture management, with nitrogen fertilisers plugging deficits rather than boosting surpluses. DairyNZ collaborated with three commercial farms to apply the P21 methods, sharing advice on successful transitions to the new system and ways to maintain efficiency.
Pastoral 21 Next Generation Dairy Systems was a collaborative* five-year farm programme that aimed to provide proven, profitable, simple, adoption-ready systems that lifted production and reduced nutrient loss.
Alongside the research, the project captured farmer experience through the use of P21 Focus Farms and case studies.
Farmlets were set up in four regions (Southland, Canterbury, Manawatu and Waikato) with the aim to address issues relevant to each region, the farmlets:
See DairyNZ Technical Series March 2017 for a summary of the P21 research programme.
DairyNZ's Scott Farm, Hamilton
Project leader: Kevin MacDonald, Dairy NZ senior scientist
Project goal: To show that an average Waikato farm could increase annual milk production by up to 200kg/ha with increased profit per hectare, while reducing N leaching from 35-50+kg/ha/year down to 20-30kg/ha/year.
Project details: Two 13ha farmlets were compared. One represented a typical Waikato farm (Current), with a stocking rate of 3.2 cows/ha. The other with a stocking rate of 2.6 cows/ha, represents a farm managed more efficiently (Future).
Summary: Using a combination of approaches (lower N inputs, a stand-off pad, higher BW cows) on the 'Future' farmlet, N leaching was reduced by 40-50% over the four winters measured.
However, milk production for the Future system was not improved, with milksolid/ha yields at c. 97% of the Current farmlet. This resulted in net profitability of the Future farmlet being about 5% less than for the Current farmlet, the difference being the cost of the standoff pad. Both farms performed at c. 20% better than the median for Waikato dairy farms.
Further reading on this project.
Massey University's No. 4 Dairy Farm, Palmerston North
Project leader: Professor Mike Hedley, Massey University
Project goal: To develop a practical housing system for the lower North Island region, that combines high production and profit with lower nitrogen (N) leaching and phosphorus (P) loss.
Project details: Two dairy systems, one with cows housed part-time in the freestall barn (2.8 cows/ha). This was compared to a more typical management system with a herd grazed-off in winter and a feed pad used on wet days in spring and winter (2.7 cows/ha).
Summary: By the 2015/2016 lactation season both the standard and housed systems had met the productivity (1,250kg MS/ha) and environmental targets (N and P loss less than 15kgN/ha/yr and 1.6kg P/ha/yr). This was mainly achieved through improved feed utilisation and longer lactations and lower urine N loads, respectively.
In 2015/2016, urinary N loads on pasture, which drives N leaching, were on average 19% lower for the house system compared with the standard system. Using autumn housing only, the subsequent N leaching reduction between the standard and house systems averaged 28% between the 2014 and 2015 drainage seasons. Total milksolids production per hectare was on average 8% higher on the house system than the standard system across the trial period. This increased production was not sufficient to cover the costs of the increased capital investment and supplementary feed required by the housed system. In 2014-2015 season the breakeven milk prices to cover capital and operating costs for Standard and House systems would need to be $4.45/kg MS and $5.75/kg MS.
Further reading on this project
Lincoln University Research Dairy Farm and Lincoln University's Ashley Dene Farm
Project leader: David Chapman, DairyNZ principal scientist
Project goal: To develop practical dairy farming systems that combine high production and profit with lower nitrate leaching.
Project details: The project included two farmlets, one with a stocking rate of 3.5 cows/ha and the other with 5 cows/ha, plus three different wintering systems (kale only, kale and oats, fodder beet only).
Summary: Environmental targets for the Dairy Farm were achieved. Averaged across the 3-year monitoring period, estimated N losses (including wintering) were reduced by >30%. Milksolids production from the farmlet 4% greater than target. Operating profit was driven greatly by milk price, a milk price of $6.30 was the tipping point, greater than this and 5 cows/ha was more profitable, less than this and 3.5 cows/ha was more profitable.
Further reading on this project
Telford Farms Dairy Unit, Telford Farm Training Institute, near Balclutha
Project leader: Ross Monaghan, AgResearch senior scientist and Dawn Dalley, DairyNZ senior scientist
Project goal: To investigate ways dairy farmers in the region can manage soils, animals and forage crops during the challenging shoulder and winter seasons, so they optimise their business and reduce their environmental footprint.
Project details: The project included two 110 cow farmlets, plus a 385 cow control herd. One farmlet treatment was managed more traditionally, using winter crop feeding while the other involved the use of an off paddock facility for indoor wintering.
Summary: Environmental targets set for the project were achieved. Averaged across the 3-year monitoring period, estimated whole-system N and P losses were reduced by > 24%, while sediment losses were reduced even further. Operating profits were not increased, however, and milksolids production from the treatment farmlets was 2-3% less than for the control.
Further reading on this project.
DairyNZ worked with three commercial farms that made changes to their farm system based on the P21 trials:
The focus farm operators had the following advice:
Eleven P21 case studies from Southland, Canterbury and Manawatu captured farmer experience in:
The Pastoral 21 experience (pdf) - The Pastoral 21 (P21) project reviewed BCS gain achieved during transitioning and winter grazing on to fodder beet and two treatments of kale crops over three winters.
Transitioning on to winter crops (pdf) - A critical factor in profitable winter grazing and targeted Body Condition Score (BCS) gain is the efficient transitioning of cows on to crop.