Partners Networking to Advance South Island Dairying

LUDF Current Research


Environmental Research Project. K Cameron, LU
Effects of ‘eco-n’ on nitrate leaching and pasture production. K Cameron LU
Pest and weed monitoring - AgRsch
The role of nutrition in lameness in Canterbury (including rumen function studies). J Gibbs, LU
Rumen Function Studies at LUDF. J Gibbs, LU
Real time, on-line monitoring for animal health and environmental impact monitoring. A C Bywater, LU
Monitoring clover root weevil establishment and build up. M McNeill, AgRsch
Calibration of the C-Dax rapid pasture meter for all New Zealand. D Dalley, DairyNZ
Pasture mass assessment by radar imagery - proof of concept. D Dalley, DairyNZ
Pasture mass assessment by satellite - testing of the Waikato algorithm on irrigated Canterbury pastures. D Dalley, DairyNZ
Measuring source and fate of agricultural nitrate: a dual-isotope approach. N Wells, LU
Improving reproductive performance in large herds - added value component. C Burke, DairyNZ
Milk progesterone sampling. C Burke, DairyNZ
Determining herbage litter yields during grazing events. T Clough, LU
Forage footpring wintering. J de Ruiter, P&F Research
Native plants rhizosphere and soil pore water quality. N Dickson, LU
2012 Online Survey of Canterbury and North Otago Farmers. A Murphy, M Pangborn, K Woodford, LU



Online Survey of Canterbury and North Otago Farmers

The objective of the online survey was to assess the LUDF's influence on defined farm management practices on South Island dairy farms. Launched in December 2012, the online survey collected data on Canterbury and North Otagoe dairy farmers demographics, their views of the farm management changes implemented at the LUDF in 2011/12, as well as their use of these 'new' and previously trialled LUDF farm management techniques.

Further indepth analysis of the survey date is on-going however, to date, the 2012 survey data suggests that participating Canterbury and North Otago dairy farmers are progressive, entrepreneurial and highly productive dairy farmers. Survey data also indicates that the LUDF provides a robust source of information on emerging issues and is an important platform for conducting innovative dairy research. Further information on survey results will be forthcoming.

Congratulations to our lucky prize winner, a dairy farmer from mid Canterbury, who has chosen the iPad.

[Researchers: A Murphy, M Pangborn, K Woodford, Lincoln University. Funded by SIDDC and Lincoln University.]




Environmental Research Project

The objective of this project is to monitor the environmental footprint of Lincoln University Dairy Farm.

The project involves measuring changes in groundwater quality using nine monitoring wells across the farm; measuring nitrate leaching losses using 60 large lysimeters installed in the pasture soil; and measuring nitrate losses in drainage water from the farm using six 100m2 drainage plots.

Results to date show that there has been little, if any, microbial contamination of the groundwater below the LUDF. The drainage plot and lysimeter studies show that with the use of eco-n nitrification inhibitor less than 30 kg N/ha/y is leached under the LUDF.

(Researchers: Keith Cameron, Hong Di, and Jim Moir, Lincoln University. Funded by Lincoln University).

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Pest and weed monitoring

Pest and weed population dynamics are being recorded to help predict and control pest damage. This information will give the farm manager advance warning and enable him to take appropriate action.

(Conducted in collaboration with AgResearch.)

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The role of nutrition in lameness in Canterbury

The project began in Spring 2005 and was completed at drying off in May 2006. The project has two arms; the on-farm recording of all lameness (> 40 farms and >30,000 cows) has been very successful, with enthusiastic producer uptake and compliance. As a 'proof of concept' it has paved the way for further use of this method of dairy health data gathering in this and other fields. While the data obtained must be considered preliminary until the final formal analysis is complete, they demonstrate a clear difference from previous published levels of lameness in NZ herds (a two-fold increase), and indicate there are significant errors in the widely held and promulgated beliefs about other aspects of the impact of lameness (e.g. on reproduction, on production, and the actual cost of lameness).

The second arm is a season long investigation of the actual rumen pH and activity of five high production cows in the LUDF herd. This work has been the first to develop a robust method to achieve this in grazing dairy cows, and in addition it is particularly valuable that this has been done in a strictly commercial, high production herd. The preliminary results indicate that previous understanding of the range and extremes of rumen pH in NZ grass fed cows is almost certainly incorrect, with pH values recorded that are far lower for longer periods than has been accepted. This work has immediate application to further research in nutritional lameness, but also to other aspects of rumen metabolism in the current NZ systems. Results for other measurements (rumination cycles, volatile fatty acid fluxes, ammonia levels) are pending.

The project has been funded for a further three years jointly by the Sustainable Farming Fund (MAF) and Dairy InSight. Future work includes an expansion of the number and geographic regions of the farms from which lameness data is obtained (Southland and the West Coast), and a comprehensive series of focused rumen function trials assessing the actual impact of altered nutritional management. From this body of work the primary South Island factors associated with the high incidence of lameness recorded are being determined, and practical, achievable strategies for reducing lameness are being developed.

(Researchers: Jim Gibbs, Jose Laporte and Richard Dewhurst. Funding from MAF (SFF), Dairy InSight, and Lincoln University).

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Rumen function studies at LUDF

A series of experiments have been completed to investigate factors affecting rumen pH in dairy cows grazing ryegrass/white clover pasture.

Rumen pH, temperature and motility were recorded in herd cows across the lactation season, beginning in the winter, including the transition period, and finishing in April. The bulk of this work consisted in describing typical rumen function in high production cows managed under a representative South Island system, and was an extension of the work begun in the previous season. This work has demonstrated that existing rumen pH thresholds for normal rumen function in grass systems do not describe high production cows under intensive management typical of the South Island . It has also demonstrated a marked diurnal variation in these rumen parameters that is directly associated with grazing management, which is in contrast to rumen function patterns reported in ration fed systems overseas.

There were also two additional experiments conducted to investigate specific feeding practices. The first of these investigated the effect of supplementary barley straw fed after the afternoon milking on diurnal variation in pH and motility of the rumen. The study has been completed and results largely analysed (we are still awaiting some alkane analysis). The study has shown no effect of straw supplementation on rumen pH, but reduced rumen motility; existing understanding of this practice appears to be incorrect. This is a topical and interesting result, and a follow up study will be conducted in late 2007 to repeat this work.

The second study has investigated effects of different levels and rates of feed intake on rumen pH and motility. The experimental model used here was to compare highly-productive dairy cows (high intake rate) and non-lactating cows (low intake rate). The animal work for this study was completed in February but still has data to be analysed. Analysis should be completed by June.

(Researcher: Jim Gibbs and Jose Laporte; funding from SIDE, $4000 2006)

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Real-time, on-line monitoring for animal health and environmental impact monitoring

The primary objective of this research is to develop the science content of real-time, on line monitoring systems which will allow development of remote monitoring and control systems for dairy farmers.

Summary Report dated January 2009.

This project has three components

A. Breath Analysis for Metabolic Stress.

The objective is to develop an automated system for analysing acetone in breath or milk head-space as an indicator of abnormal body fat mobilisation in milking cows. To date we have established acetone levels in breath and milk head space associated with milking at different times. Due to difficulties with dilution by ambient air, we decided against breath analysis and are now concentrating on a photo-ionisation detector (PID) that can detect acetone in milk head space in the range required to identify nutritional stress

Milk and blood samples from recently calved cows have been collected on one commercial farm and the LUDF to determine whether we are able to relate milk-head space acetone to blood ketone bodies under commercial conditions and to health and reproductive indices later in lactation. Milk samples were collected weekly for six weeks from 46 and 51 cows on the two farms in early lactation, and blood samples were collected from 12 cows on each farm on two occasions, three weeks apart. Milk head space was analysed using the PID and liquid milk analysed by LIC for acetone. Blood samples were analysed for βHydroxyButyrate (βHB).

We experienced some difficulties with the PID clogging up with condensation after some period of use so samples were frozen and analysed at a later time. We are attempting to find ways of overcoming this problem so that milk samples can be analysed in situ without having to be stored for later analysis. Preliminary analysis of the data indicate a very close relationship between acetone in milk head space and milk acetone concentration and a weaker relationship between either milk or head space acetone and blood βHB, which is also time dependent. Further analysis is required to determine whether this relationship is seasonal or dependent on time after calving. Health and reproduction records are being collated for analysis against the sample results.

 

B. Assessment of the Risk of Hypomagnesaemia through Monitoring Magnesium in Urine.

The objective of this work is to develop a system for monitoring magnesium in urine samples to manage the risks of hypomagnesaemia. We had previously established that a meter designed for Mg testing in wastewater from Hanna Instruments, is sufficiently accurate and robust over a range of conditions for on-farm use.

The meter as supplied does not have the capacity to download data directly to an external device so we have been re-engineering a meter to allow this. At this point we are able to intercept the signal from the processor to the display but have struck a problem with downloading the software onto a test board obtained to test the system. We are confident that this is solvable with some re-programming but this has not yet been completed. As an alternative, we are also in communication with the manufacturers of the meter to see whether they are able and willing to add a short piece of code to the meter’s programmable memory which would allow the signal from the processor to be echoed to another chip from which it would be directed to a serial or USB port.

In the meantime, a protocol for urine sample collection and analysis on farm has been developed and we are in the process of obtaining the components to implement this system. The system is designed to facilitate collection and identification of a sample so that it is electronically linked to the cow ID, and subsequently linked to the results from analysis of the sample, with the data then transferred to the farm computer. Once the Hanna meter has been modified to download data directly to an external device, the system will be implemented on the LUDF and tested to ensure that it is practical and provides the data necessary for risk assessment.

 

C. Monitoring Nitrogen in Drainage Water.

This project involves development of automatic on-farm measurement of nitrate concentrations in groundwater and drainage water from dairy farms using a nitrate specific electrode. We have successfully modified a nitrate electrode from the UK, calibrated it against standard assays in the laboratory, installed it in monitor wells on the LU dairy farm, developed an interface with a data logger and collected time series estimates of nitrate concentrations in well water samples, and established a telemetry link from the data logger to a computer situated in the laboratory on campus.

We have found that temperature fluctuations along the nitrate electrode causes variations in readings from the electrode which affects its accuracy. A new unit has been built which houses the electrode in an insulated pipe where the water is passed around the full electrode body thus reducing the temperature differential. Laboratory testing has shown that this new temperature equilibration unit has reduced variations in readings from the electrode. Field testing is now being conducted to check the effectiveness of the new assembly in monitor wells on the farm.

(Conducted by A C Bywater, K Cameron, G Edwards, A Sykes, Lincoln University , and R Pellow, SIDDC)

(Funded by Dairy InSight)

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Monitoring clover root weevil establishment and buildup

Clover root weevil (CRW), Sitona lepidus, is a pest of white clover and occurs throughout the North Island. It was first detected in the South Island in 2006 and has since spread to many South Island areas, though some areas free of CRW still occur in South Canterbury, North Otago and Southland. The weevil spreads naturally by flying and walking, but is also transported through human related activities. CRW was first found on the Lincoln University Dairy Farm (LUDF) on 10 December 2008. In response to this find, AgResearch entomologists began monitoring CRW at key times of the weevil lifecycle on the farm.
This work includes:

  • Soil coring to measure larval density, and a suction device to collect and measure adult numbers.

  • Information on adult weevil reproductive condition and parasitism.

  • Flight traps have been deployed at key times (Dec-May) to monitor adult flight activity.

  • The biocontrol agent of CRW, Microctonus aethiopoides, is established in the Lincoln area and is expected to lead to a reduction in CRW populations. CRW adults and larval populations are being measured to gauge the benefit of biocontrol.

  • The spread of the biocontrol agent from the Lincoln area was monitored in 2011 and this will be repeated in the winter of 2012. Results will be used inform farmers of the agent’s distribution in relation to their farms. The distribution map is regularly updated at www.agresearch.co.nz/crw .

In late 2010, white clover rapidly disappeared from the LUDF pasture where sampling indicated moderate larval densities of <300 m-2. Feeding by CRW larvae on the clover root system was unlikely to have been solely responsible for the observed decline, but the combination of weevil damage, root diseases, a wet winter and grazing together may have contributed to the observed losses. This loss in clover is not permanent and the percentage clover present in the pasture is now increasing again.

The work on CRW and its biocontrol agent is complemented by other research undertaken on the LUDF including the agronomic performance of pastures. Taken as a whole, these measurements will provide the LUDF with information on CRW impacts with and without biocontrol, and the benefits that biocontrol of CRW bring to the dairy platform.

(Conducted by M McNeill, AgResearch.)
(Funded by Industry/MSI).

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Calibration of the C-Dax rapid pasture meter for all New Zealand

The objective of the project is to develop calibration equations for the Rapid Pasture meter which are robust across the range of perennial herbage masses which will occur on sheep, beef and dairy pastures in NZ. The specific objective of this proposal is to develop calibration(s) for irrigated dairy pastures in Canterbury.

Pasture utilisation is well correlated with animal production and on-farm profitability. The dairy industry strategic plan wants an increase of 4 tonnes dry matter (t DM)/ha/yr in pasture utilisation by 2015. This equates to an extra 285 kg milksolids (MS)/ha (based on a conversion efficiency of 14 kg DM/kg MS). To achieve such a target management tools are required to lift the average pasture utilisation on New Zealand dairy farms. LUDF has demonstrated the benefits in terms of pasture utilisation and quality from weekly assessment of pasture mass on farm and incorporation of this information into daily management decisions.

While many farmers are acutely aware of the need to generate such information for their own property time is a premium on dairy farms and in larger operations finding the 3-6 hours a week to walk the farm with a plate meter results in this task failing to occur. The C-Dax rapid pasture meter has been developed to simplify this task, however robust calibration equations for all regions of NZ are required. While many farmers have already purchased units there is a risk that without such calibrations they will be under utilised or the information misinterpreted and the industry will not make the gains required.

(Researchers: Dawn Dalley, DairyNZ, Robyn Dynes, AgResearch.)

(Funded by Pastoral 21 project.)

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Pasture mass assessment by radar imagery – proof of concept

The objective of the project is to assess the potential of radar imagery for estimating pasture mass from irrigated dairy pastures.

Pasture utilisation is well correlated with animal production and on-farm profitability. The dairy industry strategic plan wants an increase of 4 tonnes dry matter (t DM)/ha/yr in pasture utilisation by 2015. This equates to an extra 285 kg milksolids (MS)/ha (based on a conversion efficiency of 14 kg DM/kg MS). To achieve such a target management tools are required to lift the average pasture utilisation on New Zealand dairy farms. LUDF has demonstrated the benefits in terms of pasture utilisation and quality from weekly assessment of pasture mass on farm and incorporation of this information into daily management decisions.

While many farmers are acutely aware of the need to generate such information for their own property time is a premium on dairy farms and in larger operations finding the 3-6 hours a week to walk the farm with a plate meter results in this task failing to occur. Recent research has been investigating the opportunity to use satellite imagery to estimate average pasture cover on each paddock on farms. While this method is working well in Western Australia problems with cloud cover in the Waikato have raised questions as to the suitability of this method for NZ conditions. The recent launch of the German TerraSAR-X satellite now provides an alternative approach in radar imagery which can occur independent of cloud cover. Radar imagery is already widely used in biomass assessment of tree plantations. Whether the technique is sensitive enough to accurately assess biomass at pasture cover levels requires investigation.

(Researchers: D Dalley, DairyNZ, R Dynes, AgResearch, and D Pairman, Landcare Research.)

(Funded by Pastoral 21 Project)

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Pasture mass assessment by satellite – testing of the Waikato algorithm on irrigated Canterbury pastures

The objective of the project is to assess the Waikato PfS algorithm for estimating pasture mass from irrigated dairy pastures.

Pasture utilisation is well correlated with animal production and on-farm profitability. The dairy industry strategic plan wants an increase of 4 tonnes dry matter (t DM)/ha/yr in pasture utilisation by 2015. This equates to an extra 285 kg milksolids (MS)/ha (based on a conversion efficiency of 14 kg DM/kg MS). To achieve such a target management tools are required to lift the average pasture utilisation on New Zealand dairy farms. LUDF has demonstrated the benefits in terms of pasture utilisation and quality from weekly assessment of pasture mass on farm and incorporation of this information into daily management decisions.

While many farmers are acutely aware of the need to generate such information for their own property time is a premium on dairy farms and in larger operations finding the 3-6 hours a week to walk the farm with a plate meter results in this task failing to occur. Recent research work in the Waikato has been investigating the opportunity to use satellite imagery to estimate average pasture cover on each paddock on farms. While this method is working well in Western Australia problems with cloud cover in the Waikato have created problems in delivering weekly data to farmers. In this regard a parallel project is developing a pasture growth prediction model that could be used in conjunction with satellite imagery to deliver timely information to farmers. Different weather patterns and larger farms may result in Canterbury being more suitable to this technology than other areas.

(Researchers: Dawn Dalley, DairyNZ, Robyn Dynes, AgResearch.)

(Funded by Pastoral 21 project.)

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Measuring source and fate of agricultural nitrate: a dual isotope approach

Concern over declining water quality in New Zealand is driving intensive agriculture industries (e.g. Fonterra) to require use of farm nutrient budgeting models such as AgResearch's Overseer. In order for such models to enable enhanced nitrogen (N) management on farms, and within catchments, direct and simple environmental indicators are needed. We propose using natural abundances of nitrate’s (NO3) stable isotopes as the foundation for such a precise and reliable monitoring system, based on the knowledge these isotopes will reflect the sources and processes of production and consumption of NO3.

This project is part of a 10-year long multi-partner FRST grant (overseen by Geologic and Nuclear Sciences (GNS)) to develop stable isotope indicators to i) classify vulnerability of farm units to ongoing losses of N, ii) identify proportions of river N loads from differing farm types, and iii) quantify the proportion of NO3 lost during transport.

This project, including work on the Lincoln University Dairy Farm, aims to fulfil objective iii. It is hypothesized that quantitatively linking the impact of N cycling with isotope fractionation will enable calculation of net NO3 losses (attenuation) at the catchment scale. The stable isotope indicators will be developed through evaluation of the fate and transport of NO3 and its isotopes within New Zealand grazed pastures.

(Conducted by N Wells, T Clough, R Sherlock, Lincoln University, and T Baisden, Geologic and Nuclear Sciences.)

(Funded by FRST).

 

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