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Articles 5911 - 5940 of 14774

Full-Text Articles in Agricultural Science

Understanding Livestock Grazing Impacts: A Decision Support Tool To Develop Goal-Oriented Grazing Management Strategies, S. J. Barry, K. Guenther, G. Hayes, R. Larson, G. Nader, M. Doran Feb 2023

Understanding Livestock Grazing Impacts: A Decision Support Tool To Develop Goal-Oriented Grazing Management Strategies, S. J. Barry, K. Guenther, G. Hayes, R. Larson, G. Nader, M. Doran

IGC Proceedings (1977-2023)

Managing grasslands in the western United States has become much more complex over the last few decades. A century ago the goal was to survive as a livestock producer, and grassland management involved using forage effectively and overcoming obstacles such as predators and shortages of water and feed. Today the successful grassland manager also needs to consider the diversity and health of the ecosystem as a whole. Livestock grazing can negatively and/or positively affect riparian areas, sensitive plants, and endangered wildlife. Since the impact on a specific factor will vary depending on the timing, intensity and class of livestock grazed, …

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Enhancing Grasslands Education With Decision Support Tools, H. G. Daily, J. M. Scott, J. M. Reid Feb 2023

Enhancing Grasslands Education With Decision Support Tools, H. G. Daily, J. M. Scott, J. M. Reid

IGC Proceedings (1977-2023)

We have successfully used Decision Support Tools (DST) relevant to the management of grazing enterprises to enhance problem solving skills of undergraduates in Australia. Tools such as GrassGro™ (Moore et al., 1997) and GrazFeed™ (Freer et al., 1997) are accessed from a central server by authorised users at many widely dispersed Universities across Australia using remote access to thin-client technology via an Internet portal. This has been supplemented with training for lecturers. Experience in developing appropriate teaching and learning materials and the reliable delivery of simulation software to many clients has enhanced learning outcomes at tertiary level. We …

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A Farmer Friendly Feed Budget Calculator For Grazing Management Decisions In Winter And Spring, M. Curnow, M. W. Hyder Feb 2023

A Farmer Friendly Feed Budget Calculator For Grazing Management Decisions In Winter And Spring, M. Curnow, M. W. Hyder

IGC Proceedings (1977-2023)

The Western Australian (WA) environment is Mediterranean with annual legume/grass pastures and a 6 month growing season. In autumn where over grazing can impact pasture establishment and in spring, prior to senescence, when under grazing can mean significant losses of efficiency are crucial times for grazing management. Pasture utilisation is typically low (25-35%) due to conservative stocking regimes; key to increasing productivity is increasing pasture utilisation (Grimm, 1998). Increased levels of productivity require farmer sophistication in the way they feed budget. To this end, satellite technology is being used to provide farmers in southern Australia with weekly estimates of pasture …

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Simulation Of Pasture Phase Options For Mixed Livestock And Cropping Enterprises, L. Salmon, A. D. Moore, J. F. Angus Feb 2023

Simulation Of Pasture Phase Options For Mixed Livestock And Cropping Enterprises, L. Salmon, A. D. Moore, J. F. Angus

IGC Proceedings (1977-2023)

In southern Australia, 50% of grain-producing farms also run beef and/or sheep enterprises. Legume pasture leys are used to replace soil nitrogen and manage crop disease risks. Deep-rooted perennials, predominantly lucerne (Medicago sativa), are replacing annual Trifolium subterraneum-based leys to increase pasture production. They also have the environmental benefits of limiting soil acidity, rising water tables and dryland salinity. After recent droughts depletion of soil water by lucerne has penalised wheat yields. Decision support tools can help farmers evaluate the long-term effects of grazed annual and perennial leys on animal and crop production at the whole farm …

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Grasscheck: Monitoring And Predicting Grass Production In Northern Ireland, P. D. Barrett, A. S. Laidlaw Feb 2023

Grasscheck: Monitoring And Predicting Grass Production In Northern Ireland, P. D. Barrett, A. S. Laidlaw

IGC Proceedings (1977-2023)

No abstract provided.

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Effect Of Strategy Of Forage Supplementation And Of Turnout Date In A Medium Stocking Rate System On The Main Characteristics Of Dairy Cows Grazing, P. Defrance, L. Delaby, J. M. Seuret, M. O'Donovan Feb 2023

Effect Of Strategy Of Forage Supplementation And Of Turnout Date In A Medium Stocking Rate System On The Main Characteristics Of Dairy Cows Grazing, P. Defrance, L. Delaby, J. M. Seuret, M. O'Donovan

IGC Proceedings (1977-2023)

Having a stocking rate of 2.9 cows per hectare of grassland (35 ares/cow) in Brittany offers many options for turnout date and forage supplementation strategies. For a farmer, knowing the consequences of the different options during the course of the grazing season makes grazing management decisions easier. As experiments on grazing management require considerable resources and are hardly generalisable, various spring scenarios have been tested using a dynamic decision support system, Pâtur’IN (Delaby et al., this volume).

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Grass Growth Profiles In Brittany, P. Defrance, J. M. Seuret, L. Delaby Feb 2023

Grass Growth Profiles In Brittany, P. Defrance, J. M. Seuret, L. Delaby

IGC Proceedings (1977-2023)

For farmers, knowing the local grass growth profile and the possible variations between years is very helpful in managing grazing. Indeed, the comparison with herd needs and anticipated farm cover change allows decisions to be made that will maintain the cover at the desired level. This paper proposes a ten-days grass growth profile corresponding to Brittany’s different conditions of soil, climate and pasture management.

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Using The Grassgro Decision Support Tool To Evaluate The Response In Grazing Systems To Pasture Legume Or A Grass Cultivar With Improved Nutritive Value, H. Dove, J. R. Donnelly Feb 2023

Using The Grassgro Decision Support Tool To Evaluate The Response In Grazing Systems To Pasture Legume Or A Grass Cultivar With Improved Nutritive Value, H. Dove, J. R. Donnelly

IGC Proceedings (1977-2023)

Decision support tools (DST) based on models of grazing systems allow the evaluation of changes in enterprise management on productivity and profitability. The Grassgro DST (Moore et al., 1997) uses historical weather data on a daily time step to simulate pasture growth and the resultant productivity of either grazing sheep or cattle. Different pasture species are represented within a parameter set that describes the response of pasture species to their environment. Manipulation of these parameters provides a means of evaluating, a priori, the likely responses of livestock production to ‘improved cultivars’. We report the results of simulations conducted …

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Pasture Land Management System Decision Support Software, G. E. Groover, S. R. Smith, N. D. Stone, J. J. Venuto, J. M. Galbraith Feb 2023

Pasture Land Management System Decision Support Software, G. E. Groover, S. R. Smith, N. D. Stone, J. J. Venuto, J. M. Galbraith

IGC Proceedings (1977-2023)

Controlled or rotational grazing provides benefits to producers and society through profitable and sound management of grazing land and livestock. Pasture land management system (PLMS) is a decision support system developed to help university, government, and professionals provide technical pasture management assistance to beef and dairy producers. The PLMS focuses on the balance between seasonal forage supply and nutrient demand in a dairy or beef cattle operation. It allows users to explore and compare alternatives (dividing fields into multiple paddocks, changing stocking rates, and forage species) through a visual display and embedded simulation. Users enter a description of the farm …

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Forecast Of Herbage Production Under Continuous Grazing, K. Søegaard, J. Berntsen, K. A. Nielsen, I. Thysen Feb 2023

Forecast Of Herbage Production Under Continuous Grazing, K. Søegaard, J. Berntsen, K. A. Nielsen, I. Thysen

IGC Proceedings (1977-2023)

The utilization of pasture is very sensitive to oscillations in herbage growth. The farmer’s daily planning involves decisions on pasture use as well as on the amount and composition of supplement feeding. In this planning, expected daily growth rate is an important factor. Often the knowledge and experience about the growth rate is first available after changes in management should have been made. A different growth rate than expected should lead to changes in the grazing area or in the supplement feeding. Therefore, a simple model of grass/clover growth under grazing and irrigated conditions was developed. From spring 2004, the …

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A Decision Support Tool For Seed Mixture Calculations, B. P. Berg, G. Hutton Feb 2023

A Decision Support Tool For Seed Mixture Calculations, B. P. Berg, G. Hutton

IGC Proceedings (1977-2023)

Grassland species are normally seeded in mixtures rather than monocultures. In theory, seeding rates for mixtures are simply a sum of the amount of pure live seed (PLS) of each seed lot in the mix, an amount sufficient to ensure establishment and survival of each species. Mixtures can be complex because of the number of species used (especially in conservation and reclamation programs) and variations in seed purity and seed size. Soil limitations and seeding equipment settings need to be considered and in Canada, a metric conversion may be required. All these conditions make by-hand calculations of mixtures containing more …

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Risk-Efficiency Assessment Of Haying, A. J. Romera, J. Hodgson, S. T. Morris, S. J. R. Woodward, W. D. Stirling Feb 2023

Risk-Efficiency Assessment Of Haying, A. J. Romera, J. Hodgson, S. T. Morris, S. J. R. Woodward, W. D. Stirling

IGC Proceedings (1977-2023)

Pastoral livestock farms are complex, dynamic systems subject to many forms of external disturbance. Farm Management strategies are therefore typically designed to minimize system variation. The objective of this study was to explore the impacts of different haying policies, in terms of expected profit and risk, for cow-calf farms in the Salado Region of Argentina.

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Environmental Clustering Of New Zealand Dairy Herds, J. R. Bryant, N. López-Villalobos, J. E. Pryce, C. W. Holmes Feb 2023

Environmental Clustering Of New Zealand Dairy Herds, J. R. Bryant, N. López-Villalobos, J. E. Pryce, C. W. Holmes

IGC Proceedings (1977-2023)

Previous studies have found that milk yield (a proxy for feeding level) and temperature-humidity index (THI) are important factors in explaining genotype x environment (G x E) interactions, indicating differences between the abilities of genotypes to forage or consume concentrates effectively or to cope with thermal stress (Ravagnolo and Misztal, 2000; Zwald et al., 2003). The objective of this study was to quantify and cluster (CL) herd environments within New Zealand (NZ) based on production levels, a summer heat load index (HLI) and geographical location.

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Irish Dairy Farming: Effects Of Introducing A Maize Component On Grassland Management Over The Next 50 Years, A. J. Brereton, N. M. Holden Feb 2023

Irish Dairy Farming: Effects Of Introducing A Maize Component On Grassland Management Over The Next 50 Years, A. J. Brereton, N. M. Holden

IGC Proceedings (1977-2023)

Typical management of Irish dairy units is based on a low-cost spring-calving strategy with 90% of annual feed derived from grass grown on the farm. Almost 70% of feed is from grazed grass managed by rotational grazing, the remainder is conserved forage and concentrates. The objectives of the work were to examine how the management system has to be modified when part of the dairy unit land is allocated to maize silage instead of grass silage production, and to examine how climate change over the next 50 years will impact on grass and maize management within the production system.

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Autumn Root Reserves Of Lucerne Affected Shoot Yields During The Following Spring, D. J. Moot, E. I. Teixeira Feb 2023

Autumn Root Reserves Of Lucerne Affected Shoot Yields During The Following Spring, D. J. Moot, E. I. Teixeira

IGC Proceedings (1977-2023)

Frequent grazing affects shoot yield of lucerne (Medicago sativa L.) by limiting radiation interception (Teixeira et al., 2005b) and the accumulation of endogenous reserves (C and N) in perennial storage organs like crowns and taproots (Teixeira et al., 2005a). In temperate regions, the impact of low level of perennial reserves is particularly evident during early-spring, when lucerne regrowth resumes after an overwintering period. The analysis of lucerne yield can be fragmented into its yield components of plant population, shoots per plant and yield per shoot (Volenec et al., 1987). The objective of this research was to quantify …

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Lucerne Crown And Taproot Biomass Affected Early-Spring Canopy Expansion, E. I. Teixeira, D. J. Moot, A. L. Fletcher Feb 2023

Lucerne Crown And Taproot Biomass Affected Early-Spring Canopy Expansion, E. I. Teixeira, D. J. Moot, A. L. Fletcher

IGC Proceedings (1977-2023)

Leaf area index (LAI) quantifies canopy expansion in crops and is used in lucerne (Medicago sativa L.) simulation models to predict daily PAR interception (PAR i). This then drives yield through radiation use efficiency (RUE) (Gosse et al., 1984). In perennial crops, like lucerne, the level of biomass stored in crown and taproot may affect canopy expansion in subsequent regrowth cycles (Avice et al., 1997). In temperate regions the impact of this is likely to be greatest in early-spring, when low temperatures delay development. The objective of the current research was to identify whether contrasting levels of winter biomass in …

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Extending The Grazing Season With Turnips, P. Thomet, S. Kohler Feb 2023

Extending The Grazing Season With Turnips, P. Thomet, S. Kohler

IGC Proceedings (1977-2023)

A comparison of the actual feeding costs on 86 typical Swiss dairy farms confirmed that the production of hay and grass silage is very expensive with costs from the field to intake in the range of 20-25 Euro cents/kg of dry matter (DM). Options to extend the grazing season for dairy cows in the late autumn and early winter, and hence reduce winter feeding costs, would therefore be welcome (Penrose et al., 1996). The aim of the study was to compare the DM production potential of summer-seeded turnips with other brassicas and Italian ryegrass and to test whether dairy cows …

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Milk Production Performance Based On Grazed Grassland In Switzerland, P. Thomet, H. Menzi Feb 2023

Milk Production Performance Based On Grazed Grassland In Switzerland, P. Thomet, H. Menzi

IGC Proceedings (1977-2023)

A common feature of profitable dairy systems is the use of large amounts of low cost feed. One approach to improve the competitive ability of the dairy production therefore is to promote grazing (Dillon et al., 1995). A comparison of the actual feeding costs on typical Swiss dairy farms showed that hay and grass silage were four times and concentrates seven times more expensive than grazed grass. A maximum utilisation of grazed grass can be achieved with a seasonal production system, which synchronises the cow’s feed requirements with pasture growth. This strategy was implemented and consistently optimised on an …

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The Effect Of Inclusion Of A Range Of Supplementary Feeds On Herbage Intake, Total Dry Matter Intake And Substitution Rate In Grazing Dairy Cows, S. J. Morrison, D. C. Patterson, S. Dawson, C. P. Ferris Feb 2023

The Effect Of Inclusion Of A Range Of Supplementary Feeds On Herbage Intake, Total Dry Matter Intake And Substitution Rate In Grazing Dairy Cows, S. J. Morrison, D. C. Patterson, S. Dawson, C. P. Ferris

IGC Proceedings (1977-2023)

The milk production potential of dairy cows has increased substantially over the past two decades. This development presents new challenges for managing dairy cows during grazing, particularly where the objective is to maximise the proportion of energy in the diet derived from forage. The objective of the current study was to explore supplementation strategies to maintain high total forage intakes from grazed grass supplemented with alternative forage supplements in dairy cows during the grazing season. A second objective of the study was to examine the effect of supplement on substitution rate (SR) and milk yield response.

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White Clover Soil Fatigue: An Establishment Problem On Large And Intensive Dairy Farms, K. Søegaard, K. Møller Feb 2023

White Clover Soil Fatigue: An Establishment Problem On Large And Intensive Dairy Farms, K. Søegaard, K. Møller

IGC Proceedings (1977-2023)

In recent years a new constraint, clover soil fatigue, has appeared for the establishment of white clover (Trifolium repens) in Denmark. Increasing dairy farm size has led to more intensive use of clover in crop rotation schemes in the grazing areas located at convenient distances from stables. It has become common practice to establish new clover/grass in the fields just after ploughing clover/grass swards, and soil fatigue is becoming more common. On fatigued land the clover plants emerge, then become stunted and eventually disappear within the same year. The problem tends to cover the full field area. Obviously, …

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Effect Of Farm Grass Cover At Turnout On The Grazing Management Of Spring Calving Dairy Cows, M. O'Donovan, L. Delaby, P. Defrance Feb 2023

Effect Of Farm Grass Cover At Turnout On The Grazing Management Of Spring Calving Dairy Cows, M. O'Donovan, L. Delaby, P. Defrance

IGC Proceedings (1977-2023)

Early spring grazing is an objective for most Irish dairy farmers. If more grass is included in the diet of the cow in early lactation, the profitability of the farm system can be increased. Post turnout, dairy cow feeding management varies with the amount of farm grass cover (FC) available. Experiments on the consequences of different FC at turnout require large resources and all scenarios cannot be accounted for. Consequently, a decision support system, Pâtur’IN (Delaby et al., this volume), was used to describe the effects of various FC at turnout on grazing management in spring.

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What Supplementation Type For Spring Calving Dairy Cows At Grass In Autumn?, M. O'Donovan, E. Kennedy, T. Guinee, J. J. Murphy Feb 2023

What Supplementation Type For Spring Calving Dairy Cows At Grass In Autumn?, M. O'Donovan, E. Kennedy, T. Guinee, J. J. Murphy

IGC Proceedings (1977-2023)

In spring-calving herds the requirement for conserved forages for indoor feeding is very limited but these feeds may have a role to play as buffer feeds in the spring and autumn periods when grass supply is less than required or as alternatives to concentrates on pasture for cows in early lactation. The objective of this experiment was to compare alternative forages and concentrates as buffer feeds on pasture with spring-calving cows in the autumn.

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Manipulation Of Grass Growth Through Strategic Distribution Of Nitrogen Fertilisation, M. Stettler, P. Thomet Feb 2023

Manipulation Of Grass Growth Through Strategic Distribution Of Nitrogen Fertilisation, M. Stettler, P. Thomet

IGC Proceedings (1977-2023)

The objective of this study was to evaluate possibilities and limits of manipulating the grass growth of pastures by different nitrogen (N) application strategies with the aim to better synchronise grass supply and feed demand. In Switzerland, the use of N is strongly restricted by legislation. An efficient and well allocated N fertilisation is therefore important.

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A Comparison Of Three Systems Of Milk Production With Different Land Use Strategies, L. Shalloo, P. Dillon, J. J. Murphy Feb 2023

A Comparison Of Three Systems Of Milk Production With Different Land Use Strategies, L. Shalloo, P. Dillon, J. J. Murphy

IGC Proceedings (1977-2023)

Under the Luxemburg agreement FAPRI-Ireland (Breen & Hennessey 2003) projects that milk price will decrease by 5.0 to 5.5 c/l because of reductions in support for butter and skimmed milk powder. These changes mean that many dairy farmers need to reappraise their systems of milk production and consider necessary adjustments that will ensure viability in the longer term. The objective of this study was to model three different systems of milk production in scenarios where quota, cow numbers or land was restricted.

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Project Opti-Milk: Optimisation And Comparison Of High Yield And Low Input Milk Production Strategies On Pilot Farms In The Lowlands Of Switzerland, H. Menzi, T. Blaettler, P. Thomet, B. Durgiai, S. Kohler, R. Staehli, R. Mueller, P. Kunz Feb 2023

Project Opti-Milk: Optimisation And Comparison Of High Yield And Low Input Milk Production Strategies On Pilot Farms In The Lowlands Of Switzerland, H. Menzi, T. Blaettler, P. Thomet, B. Durgiai, S. Kohler, R. Staehli, R. Mueller, P. Kunz

IGC Proceedings (1977-2023)

Compared to other European countries milk production costs in Switzerland are high. Therefore Swiss milk producers must drastically reduce their costs. The high yield strategy (HY) and the full grazing (FG) or low-cost strategy appear most promising, at least for the lowland regions. Although the basic knowledge is available for both strategies, they have been applied very little in Switzerland in a consistent and optimised form.

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Assessment Of Grass Production And Efficiency Of Utilisation On Three Northern Ireland Dairy Farms, A. J. Dale, P. D. Barrett, C. S. Mayne Feb 2023

Assessment Of Grass Production And Efficiency Of Utilisation On Three Northern Ireland Dairy Farms, A. J. Dale, P. D. Barrett, C. S. Mayne

IGC Proceedings (1977-2023)

Recent research has shown that grazed grass can be an expensive forage for milk production, particularly if herbage production is low or utilisation is inefficient. There is very limited data on the level of herbage grown and utilised on commercial farms. The objective of this project was to quantify grass production and efficiency of utilisation on farm to substantiate the potential of grazed grass for profitable milk production.

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The Effect Of Grassland Management On Bovine Nitrogen Efficiency, N. J. Hoekstra, R. P. O. Schulte, E. A. Lantinga, P. C. Struik Feb 2023

The Effect Of Grassland Management On Bovine Nitrogen Efficiency, N. J. Hoekstra, R. P. O. Schulte, E. A. Lantinga, P. C. Struik

IGC Proceedings (1977-2023)

Nitrogen (N) losses through grazing bovines are at the heart of the current debate on environment and agriculture. N utilisation of grazing bovines is predominantly determined by the form and amount of energy and protein in their diet, which in Ireland consists mainly of grazed grass. The two main problems of grazed grass with respect to animal N utilisation are 1) the imbalance between total N content and energy content, and 2) the lack of synchronisation between the release of N and carbohydrates in the rumen. It was hypothesised that both the balance and synchronisation of N and energy in …

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The Effect Of Stocking Rate And Initial Grass Height On Herbage Production And Utilization, And Milk Production Per Unit Area Under Set Stocking By Lactating Dairy Cows, H. Nakatsuji, T. Endo, S. Bawm, T. Mitani, M. Takahashi, K. Ueda, S. Kondo Feb 2023

The Effect Of Stocking Rate And Initial Grass Height On Herbage Production And Utilization, And Milk Production Per Unit Area Under Set Stocking By Lactating Dairy Cows, H. Nakatsuji, T. Endo, S. Bawm, T. Mitani, M. Takahashi, K. Ueda, S. Kondo

IGC Proceedings (1977-2023)

In our previous study with lactating dairy cows (Nakatsuji et al., 2004), annual herbage production and utilization, and milk production per unit area under set stocking was not always lower than under rotational grazing at the same stocking rate (6 cows/ha). Furthermore, there was a possibility that set stocking could increase pasture utilization and milk production over rotational grazing when cows were grazed at adequate stocking rate and at the appropriate initial date of grazing. The purpose of the present study was to evaluate the effect of stocking rate and initial grass height on herbage production and utilization, and …

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Better Dairy Farm Management Increases The Economic Return From Phosphorus, J. D. Morton Feb 2023

Better Dairy Farm Management Increases The Economic Return From Phosphorus, J. D. Morton

IGC Proceedings (1977-2023)

Some 60% of New Zealand dairy farms on allophanic and sedimentary soils have soil Olsen phosphorus (P) levels to 75 mm depth above the target range for near-maximum pasture production of 20-30 µg/ml (Roberts & Morton 1999). For an economic response in milksolids (MS) production from high Olsen P, the pasture needs to be capable of high production, and the extra pasture grown be converted to milk. This paper seeks to justify this contention and outline some of the farm management practices required to achieve it.

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The Effect Of Two Magnesium Fertilisers, Kieserite And Mgo, On Herbage Mg Content, M. B. O'Connor, A. H. C. Roberts, R. Haerdter Feb 2023

The Effect Of Two Magnesium Fertilisers, Kieserite And Mgo, On Herbage Mg Content, M. B. O'Connor, A. H. C. Roberts, R. Haerdter

IGC Proceedings (1977-2023)

Supplementing Mg to dairy cows is widely practised in New Zealand. Various methods are used including drenching, pasture dusting, water trough treatment and adding to hay, silage and other feedstuffs (Young et al., 1979). Fertiliser Mg (calcined magnesite, MgO) is widely used to maintain soil Mg status but research has shown that using fertiliser Mg to achieve good soil, pasture and animal Mg status requires large inputs of Mg (120 kg/ha) and maintaining blood serum Mg status in dairy cows tends to be short-lived without further animal supplementation (O’Connor et al., 1987). The objective of these experiments was …

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