scholarly journals Linking a whole farm model to the APSIM suite to predict N leaching on New Zealand dairy farms

2011 ◽  
Keyword(s):  
New Zealand ◽  
Dairy Farms ◽  
N Leaching ◽  
Farm Model

The potential of diverse pastures to reduce nitrogen leaching on New Zealand dairy farms

2014 ◽  
Vol 54 (12) ◽  
pp. 1971 ◽  
Author(s):  
P. C. Beukes ◽  
P. Gregorini ◽  
A. J. Romera ◽  
S. L. Woodward ◽  
E. N. Khaembah ◽  
...  
Keyword(s):  
New Zealand ◽  
System Analysis ◽  
Dilution Effect ◽  
Dairy Farms ◽  
Water Soluble ◽  
Scale Model ◽  
Soluble Carbohydrate ◽  
N Leaching ◽  
Protein Ratio ◽  
Total N

The largest contributor to nitrogen (N) leaching from ryegrass-clover pasture based dairy farms is the surplus feed N excreted as urinary N (UN) onto pastures. Pastures consisting of mixtures of ryegrass, herbs and legumes (diverse pastures) have shown potential to yield similar DM, but with a lower N content and a higher water soluble carbohydrate : crude protein ratio compared with standard ryegrass–clover pastures. These diverse pastures have shown the potential to lower the UN excreted by dairy cows in short-term, late-lactation studies. This modelling study was designed to scale the results from component studies up to farm and over a full season to evaluate the potential of diverse pastures to become a suitable strategy for reducing N leaching on New Zealand dairy farms. The Molly cow model was tested against observed data from one indoor and one outdoor study where feeding diverse pasture resulted in UN (N excreted in urine g/day) reductions of 50% and 17%, respectively. The model predicted UN reductions of 23% and 17%. Farm-scale model scenarios, where 20% or 50% of the farm was sown with diverse pastures, resulted in 2% and 6% reductions in UN deposited onto paddocks. This reduction was smaller than expected with some system interactions related to seasonal feed supply, diet composition and total N intake being likely to play a role. The reduction in UN onto paddocks, together with a dilution effect from larger urine volumes per cow per day as a result of lower DM% of diverse pastures, resulted in N leaching reductions of 11% and 19% for the two scenarios, respectively. This potential to reduce N leaching needs to be evaluated further in the context of farm profitability when other aspects of diverse pastures such as yield, persistency, drought resistance and ability to extract N from the soil becomes part of the farm-system analysis.

scholarly journals Implications of increased use of brought-in feeds on potential environmental effects of dairy farms in Waikato

2017 ◽  
Vol 79 ◽  
pp. 139-145
Author(s):  
S.F. Ledgard ◽  
N.L. Bartlett ◽  
P.J. Van Boheemen ◽  
B.R. Wilton ◽  
S.B. Allen ◽  
...  
Keyword(s):  
Land Use ◽  
New Zealand ◽  
Carbon Footprint ◽  
Environmental Effects ◽  
Dairy Farms ◽  
N Leaching ◽  
Nutrient Efficiency ◽  
High Feed ◽  
On Farm ◽  
Farm System

Abstract The effects of increased use of brought-in feeds were evaluated across 25 dairy farms in central Waikato. Farms were classified into low, medium and high feedinput categories based on 1200 kg DM/cow, covering a range typical of that in the main dairying regions of New Zealand. Average milksolids (MS)/ha was 1087 and 1900 kg in the low and high feed-input categories, but total land-use/tonne MS was the same when all off-farm land was accounted for. Average estimated on-farm nitrogen (N) leaching increased from 26 to 30 kg N/ha/year between the low and high feed-input categories, but off-farm leaching sources were equivalent to an increase of 20 and 84%, respectively. Greenhouse gas emissions/on-farm hectare were 61% higher on high feed-input farms, but the carbon footprint and N leaching per tonne MS were similar across feed-input categories. High feed-input farms used feed-pads and increased effluent area (66 versus 21% of farm) to increase nutrient efficiency. Mitigation analyses indicated that N leaching could be decreased by optimising effluent area, reducing N fertiliser rate and utilising low-N feeds. Keywords: nitrogen leaching, whole farm system, greenhouse gases, land use

scholarly journals Using a climate-driven farm model to predict pasture mass for individual paddocks on New Zealand dairy farms

2008 ◽  
pp. 159-163
Author(s):  
P.C. Beukes ◽  
C.E.F. Clark ◽  
A.J. Romera ◽  
G. Levy ◽  
J.M. Lee
Keyword(s):  
Growth Rate ◽  
Decision Support ◽  
New Zealand ◽  
Dairy Farms ◽  
Visual Assessment ◽  
Accurate Prediction ◽  
Grazing Management ◽  
Farm Model ◽  
Allocation Planning

Accurate prediction of pasture mass on dairy farms would allow for greater precision and feed allocation planning, and therefore greater utilisation and more profit. Current methods to collect these data, e.g. by rising plate meter or visual assessment, are tedious and time consuming. Daily pasture growth rate (kg DM/ha/ day) can be added to a measured post-grazing residual to estimate the increase in pasture mass after a grazing or cutting event. Keywords: decision support, grazing management, pasture growth rate

Automatic Milking Systems: an option to address the labour shortage on New Zealand dairy farms?

2002 ◽  
pp. 39-43
Author(s):  
J.G. Jago ◽  
M.W. Woolford
Keyword(s):  
New Zealand ◽  
Dairy Industry ◽  
Research Programme ◽  
Working Hours ◽  
Dairy Farms ◽  
Small Scale ◽  
Labour Shortage ◽  
Commercial Farms ◽  
Grazing Systems ◽  
Automatic Milking Systems

There is a growing shortage of labour within the dairy industry. To address this the industry needs to attract more people and/or reduce the labour requirements on dairy farms. Current milk harvesting techniques contribute to both the labour requirements and the current labour shortage within the industry as the process is labour-intensive and necessitates long and unsociable working hours. Automated milking systems (AMS) have been in operation, albeit on a small scale, on commercial farms in Europe for a decade and may have the potential to address labour issues within the New Zealand dairy industry. A research programme has been established (The Greenfield Project) which aims to determine the feasibility of automated milking under New Zealand dairying conditions. A Fullwoods MERLIN AMS has been installed on a protoype farmlet and is successfully milking a small herd of 41 cows. Progress from the prototype Greenfields system offers considerable potential for implementing AMS in extensive grazing systems. Keywords: automated milking systems, dairy cattle, grazing, labour

An evaluation of a strategic de-stocking regime for dairying to improve nitrogen efficiency and reduce nitrate leaching from dairy farms in nitrate-sensitive areas

2000 ◽  
pp. 105-110
Author(s):  
Cecile De Klein ◽  
Jim Paton ◽  
Stewart Ledgard
Keyword(s):  
New Zealand ◽  
Nitrate Leaching ◽  
Management Practice ◽  
Field Measurements ◽  
Dairy Farms ◽  
Nitrogen Efficiency ◽  
Management Tool ◽  
Pasture Production ◽  
Leaching Losses ◽  
Sensitive Areas

Strategic de-stocking in winter is a common management practice on dairy farms in Southland, New Zealand, to protect the soil against pugging damage. This paper examines whether this practice can also be used to reduce nitrate leaching losses. Model analyses and field measurements were used to estimate nitrate leaching losses and pasture production under two strategic de-stocking regimes: 3 months off-farm or 5 months on a feed pad with effluent collected and applied back to the land. The model analyses, based on the results of a long-term farmlet study under conventional grazing and on information for an average New Zealand farm, suggested that the 3- or 5-month de-stocking could reduce nitrate leaching losses by about 20% or 35-50%, respectively compared to a conventional grazing system. Field measurements on the Taieri Plain in Otago support these findings, although the results to date are confounded by drought conditions during the 1998 and 1999 seasons. The average nitrate concentration of the drainage water of a 5-month strategic de-stocking treatment was about 60% lower than under conventional grazing. Pasture production of the 5-month strategic de-stocking regime with effluent return was estimated based on data for apparent N efficiency of excreta patches versus uniformlyspread farm dairy effluent N. The results suggested that a strategic de-stocking regime could increase pasture production by about 2 to 8%. A cost/ benefit analysis of the 5-month de-stocking system using a feed pad, comparing additional capital and operational costs with additional income from a 5% increase in DM production, show a positive return on capital for an average New Zealand dairy farm. This suggests that a strategic destocking system has good potential as a management tool to reduce nitrate leaching losses in nitrate sensitive areas whilst being economically viable, particularly on farms where an effluent application system or a feed pad are already in place. Keywords: dairying, feed pads, nitrate leaching, nitrogen efficiency, productivity, strategic de-stocking

Characterisation of AmpC and extended-spectrum beta-lactamase producing E. coli from New Zealand dairy farms

2021 ◽  
Vol 117 ◽  
pp. 104998
Author(s):  
Sara A. Burgess ◽  
Jacinda Aplin ◽  
Patrick J. Biggs ◽  
Georgia Breckell ◽  
Jackie Benschop ◽  
...  
Keyword(s):  
New Zealand ◽  
Dairy Farms ◽  
Beta Lactamase ◽  
Extended Spectrum Beta Lactamase ◽  
E Coli ◽  
Extended Spectrum

scholarly journals Estimation of dairy pastures - the need for standardisation

1997 ◽  
pp. 221-225 ◽  
Author(s):  
N.A. Thomson ◽  
D.A. Mccallum ◽  
S. Howse ◽  
C.W. Holmes ◽  
P.N.P. Matthews ◽  
...  
Keyword(s):  
New Zealand ◽  
Dairy Farms ◽  
Ground Level ◽  
Common System ◽  
Standard Observer ◽  
Standard Calibration ◽  
Standard Set ◽  
Research Centres ◽  
Calibration Equations

A study was undertaken to determine the reason for the differences in the estimation of pasture mass between dairying research centres in New Zealand and to define a common system of estimation that would overcome these differences and be able to describe the pasture situation on commercial dairy farms in different parts of New Zealand. Differences in the visual estimation of pasture between a standard observer and a local observer at the different dairying research centres in the order of 900 kg DM/ha were identified. This was attributed to a lack of regular visual calibration of persons who regularly assessed pasture, as differences between centres in the actual harvested DM yields of the visually assessed plots varied less (200-400 kg DM/ha). To achieve uniformity it is recommended that all centres measure total herbage mass (the amount of herbage above ground level) to regularly calibrate pasture assessment in dairy grazing management studies and on dairy farms. A reasonably consistent estimation of average farm cover, the ranking of paddocks (r2 > 0.9) for the purposes of determining grazing order and the estimation of pre- and post-grazing herbage mass was achieved using the rising plate meter and L'Huillier & Thomson's standard set of calibration equations published in 1988. With these recommendations, estimation of pasture will be more uniform. Standard calibration of the plate meter for the determination of rate of DM disappearance (pre-post grazing) achieved less consistency. Keywords: herbage mass, pasture assessment, pasture height, rising plate meter, visual pasture estimation

scholarly journals ECONOMICS OF NITROGEN USE IN DAIRYING

1982 ◽  
pp. 70-75
Author(s):  
D.A.L. Buxton
Keyword(s):  
New Zealand ◽  
Research Work ◽  
Dairy Farms ◽  
Early Spring ◽  
The Other ◽  
Stocking Rate ◽  
Nitrogen Use

During the last 10 to 15 years, the use of fertiliser N at low rates on New Zealand dairy farms has become more popular. There are many ways in which fertiliser N can be used to increase pasture and milkfat production. Five of those options are analysed, viz. I. High rates of N. 2. Bridging a spring feed deficit. 3. Increasing stocking rate. 4. Earlier calving. 5. More cow condition. Research work is finding the best times and rates of application of N. The extra pasture produced must then be utilised to maximise milkfat responses. Trials have shown that the use of high rates of fertiliser N ( > 80 kg N/ha) is unlikely to be profitable on N.Z. dairy farms. N used to enable more cows to be wintered, and then milked in early spring, appears to be very profitable, due to better utilisation of later spring-autumn pasture growth. The other three options are also profitable, but the increase in total farm milkfat production is only 3 to 4%. The options need to be tested more thoroughly with models and grazing experiments.

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