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Articles 3211 - 3240 of 12120

Full-Text Articles in Physical Sciences and Mathematics

The Effects Of A New Plastic Film On The Microbial And Fermentation Quality Of Italian Ryegrass Bale Silages, G. Borreani, E. Tabacco Feb 2023

The Effects Of A New Plastic Film On The Microbial And Fermentation Quality Of Italian Ryegrass Bale Silages, G. Borreani, E. Tabacco

IGC Proceedings (1993-2023)

Problems associated with big bale silage include the high permeability of plastic wrapping films to O2, their low resistance to damage and the large amount of plastic that must be used to limit aerobic deterioration during conservation. Low permeability film, used in the packaging of food and recently proposed for bunker silos (Degano, 1999), could reduce fungal development in bale silage. The aim of this work was to compare the microbial and fermentation quality of big-baled silage, wrapped with commercially available plastic film and a new stretch film with low O2 permeability, over different conservation periods.


The Effect Of Neutralising Formic Acid On Fermentation Of Fresh And Wilted Grass Silage, E. Saarisalo, S. Jaakkola Feb 2023

The Effect Of Neutralising Formic Acid On Fermentation Of Fresh And Wilted Grass Silage, E. Saarisalo, S. Jaakkola

IGC Proceedings (1993-2023)

Rapid drop in pH is essential for minimising proteolysis and successful ensiling. Use of acid additives typically reduces protein degradation and restricts fermentation. The effects of acid additive depend on application rate and type of herbage. Corrosiveness and risks in handling formic acid (FA) can be reduced by using salts of FA like ammonium formate (AF). Increasing proportions of AF replacing FA were applied into grass at two dry matter (DM) contents to evaluate the effects of neutralised FA on silage pH and fermentation.


Influence Of Different Alfalfa-Grass Mixtures And The Use Of Additives On Nutritive Value And Fermentation Of Silage, P. Lättemäe, U. Tamm Feb 2023

Influence Of Different Alfalfa-Grass Mixtures And The Use Of Additives On Nutritive Value And Fermentation Of Silage, P. Lättemäe, U. Tamm

IGC Proceedings (1993-2023)

Legumes have a high nutritive value but they are known to be difficult to ensile and often result in poorly fermented silage. This is usually due to high buffering capacity and low available sugar concentration. However, the results have shown that silage quality can considerably be improved by using additives or when legume-grass mixtures are ensiled (Lättemäe & Tamm, 2002). Different legume-grass mixtures differ in their ensiling properties and also may affect the fermentation. The objective of this experiment was to study the effect of alfalfa-grass mixtures and the use of additives on nutritive value and fermentation of silage.


Effects Of Inoculation Of Lab On Fermentation Pattern And Clostridia Spores In Easily Ensilable Grass Silages, J. Thaysen, G. Pahlow, E. Mathies Feb 2023

Effects Of Inoculation Of Lab On Fermentation Pattern And Clostridia Spores In Easily Ensilable Grass Silages, J. Thaysen, G. Pahlow, E. Mathies

IGC Proceedings (1993-2023)

Clostridia can damage the protein quality of grass silages. They cause high gas losses during the fermentation process and quality problems in dairy products like semi-hard cheeses. In comparison to the effect of chemicals such as nitrite on undesirable clostridia in grass silages the respective inhibitory mechanism of LAB requires further investigation. The objective of this experiment was to study under laboratory conditions novel isolates of lactic acid bacteria (LAB), selected for their inhibitory effect on clostridia in grass silages.


Effect Of Biological Additives In Red Clover – Timothy Conservation, A. Olt, H. Kaldmäe, E. Songisepp, O. Kärt Feb 2023

Effect Of Biological Additives In Red Clover – Timothy Conservation, A. Olt, H. Kaldmäe, E. Songisepp, O. Kärt

IGC Proceedings (1993-2023)

Red clover at early flower bud formation is difficult to ensile. For efficient improvement of the quality of leguminous silages, chemical additives are used. The present research focuses on the effectiveness of biological additives with different composition on the fermentation and quality of clover silage.


Application Of A New Inoculant “Chikuso-1” For Silage Preparation Of Forage Paddy Rice, Y. Cai, C. Xu, S. Ennahar, N. Hino, N. Yoshida, M. Ogawa Feb 2023

Application Of A New Inoculant “Chikuso-1” For Silage Preparation Of Forage Paddy Rice, Y. Cai, C. Xu, S. Ennahar, N. Hino, N. Yoshida, M. Ogawa

IGC Proceedings (1993-2023)

Forage paddy rice is currently one of the most important silage crops in Japan. In fact, the use of paddy rice culture for silage production has been steadily increasing in recent years, not only because this represents a new way towards achieving self-sufficiency in animal feed, but also because of the interest of combining crop cultivation and livestock farming as a more effective use of idle paddy fields that often remain unused. However, the preparation of quality silage from paddy rice and its long-term storage are often challenging (Cai et al., 1999, 2003). In this study, a new bacterial …


The Influence Of The Application Of A Biological Additive On The Fermentation Process Of Red Clover Silage, Ľ. Rajčáková, R. Mlynár, M. Gallo Feb 2023

The Influence Of The Application Of A Biological Additive On The Fermentation Process Of Red Clover Silage, Ľ. Rajčáková, R. Mlynár, M. Gallo

IGC Proceedings (1993-2023)

In Slovakia, mainly in the submontane and mountainous regions, growing of red clover is an important source of proteinous feeds. It is grown on 3.0% of arable land. It was the aim of this work to verify the possibilities of using a biological additive in red clover silage conservation.


Synergism Of Chemical And Microbial Additives On Sugarcane (Saccharum Officinaruml.) Silage Fermentation, T. F. Bernardes, G. R. Siqueira, R. P. Schocken-Inturrino, A. P. T. P. Roth, R. A. Reis Feb 2023

Synergism Of Chemical And Microbial Additives On Sugarcane (Saccharum Officinaruml.) Silage Fermentation, T. F. Bernardes, G. R. Siqueira, R. P. Schocken-Inturrino, A. P. T. P. Roth, R. A. Reis

IGC Proceedings (1993-2023)

Sugarcane has a high productive potential (30 t DM/year) and it is commonly used in its fresh form. The ensiling of sugarcane is increasing but little research has been carried out to reduce nutrient losses during fermentation.


Effects Of Stage Of Growth And Inoculation On Fermentation Quality Of Field Pea Silage, G. Borreani, L. Cavallarin, S. Antoniazzi, E. Tobacco Feb 2023

Effects Of Stage Of Growth And Inoculation On Fermentation Quality Of Field Pea Silage, G. Borreani, L. Cavallarin, S. Antoniazzi, E. Tobacco

IGC Proceedings (1993-2023)

Field peas (Pisum sativum L.) are a short-term catch crop with a high crude protein content, which provides a high forage yield in a short growing period. Since field peas are a succulent crop and are difficult to field cure, it is preferable to directly ensile them to prevent weather damage and excessive grain losses. The onset of lodging is delayed in field pea varieties, since the crop is supported by the tendrils in a more erect manner, and this allows easy harvesting without soil contamination even at advanced stages of maturity (Koivisto et al., 2003). To …


Inoculant Effects On Ensiling And In Vitro Gas Production In Lucerne Silage, R. E. Muck, I. Filya, F. E. Contreras-Govea Feb 2023

Inoculant Effects On Ensiling And In Vitro Gas Production In Lucerne Silage, R. E. Muck, I. Filya, F. E. Contreras-Govea

IGC Proceedings (1993-2023)

Inoculants are the most common additives used in making silage. While inoculant effects on fermentation and dry matter (DM) recovery are understood, animal performance effects are often greater than expected. In vitro analyses may help uncover how inoculants affect rumen fermentation and ultimately dairy cattle performance. Our objective was to study how inoculation of lucerne silage affected in vitro gas production.


A Novel Bacterial Silage Additive Effective Against Clostridial Fermentation, E. Mayrhuber, M. Holzer, W. Kramer, E. Mathies Feb 2023

A Novel Bacterial Silage Additive Effective Against Clostridial Fermentation, E. Mayrhuber, M. Holzer, W. Kramer, E. Mathies

IGC Proceedings (1993-2023)

Silage quality is determined by factors including the content of butyric acid and ammonium-N. These parameters have to be restricted especially in lightly wilted silages due to a higher risk of clostridia contamination. In this study a novel silage additive was tested in grass silages of low dry matter content. The objective of this experiment was to explore the effect of the silage additive on quality parameters in comparison to an untreated control.


In Vitro Gas Production And Bacterial Biomass Estimation For Lucerne Silage Inoculated With One Of Three Lactic Acid Bacterial Inoculants, F. E. Contreras-Govea, R. E. Muck, I. Filya, D. R. Mertens, P. J. Weimer Feb 2023

In Vitro Gas Production And Bacterial Biomass Estimation For Lucerne Silage Inoculated With One Of Three Lactic Acid Bacterial Inoculants, F. E. Contreras-Govea, R. E. Muck, I. Filya, D. R. Mertens, P. J. Weimer

IGC Proceedings (1993-2023)

Silages inoculated with microbial inoculants frequently have a lower pH than non-inoculated crops. Less often inoculated crops have a positive effect on milk production (Weinberg & Muck, 1996). One hypothesis is that bacterial inoculants produce a probiotic effect that could enhance animal performance (Weinberg & Muck, 1996). Our objective was to use the method of Blümmel et al. (1997) to study differences in in vitro fermentation among lucerne silages inoculated with three microbial inoculants.


Paying For Our Keep: Grasslands Decision Support In More-Developed Countries, Andrew D. Moore Feb 2023

Paying For Our Keep: Grasslands Decision Support In More-Developed Countries, Andrew D. Moore

IGC Proceedings (1993-2023)

Key points

1. A survey of decision support (DS) tools in grassland agriculture illustrates the diversity of decisions supported and of delivery technologies that are used. Larger, whole-enterprise planning tools are undergoing a period where their user interfaces are being adapted to better reflect the requirements and practice of advisory users.

2. The history of use of GrassGro, a ‘versatile simulator’, is used to illustrate how versatile tools attract a diverse range of users and uses. Lessons learnt by the GrassGro team are discussed.

3. Uptake rates of DS tools in grasslands are generally lower than was expected a decade …


Survey Of Tetraploid And Diploid Perennial Pastures In The Waikato For Number Of Spores Produced By The Fungus Pithomyces Chartarum, J. P. J. Eerens, W. W. Nichol, J. Waller, J. M. Mellsop, M. R. Trolove, M. G. Norriss Feb 2023

Survey Of Tetraploid And Diploid Perennial Pastures In The Waikato For Number Of Spores Produced By The Fungus Pithomyces Chartarum, J. P. J. Eerens, W. W. Nichol, J. Waller, J. M. Mellsop, M. R. Trolove, M. G. Norriss

IGC Proceedings (1993-2023)

Facial eczema (FE) is a disease of livestock, caused by a toxin released into the bloodstream after digestion of spores of Pithomyces chartarum, a fungus residing in necrotic plant material in the base of pastures (di Menna & Bailey, 1973). Spore numbers tend to be highest in warm, humid conditions, where high post grazing residuals have lead to a build up of necrotic plant material. Tetraploid perennial ryegrass pastures tend to be more palatable, and with lower post gazing residuals, than equivalent diploid pastures; thus we hypothesised that spore numbers would be lower in tetraploid pastures. A survey of …


A Survey Of European Regional Adaptation In Italian Ryegrass Varieties, T. J. Gilliland, A. J. P. Wijk Feb 2023

A Survey Of European Regional Adaptation In Italian Ryegrass Varieties, T. J. Gilliland, A. J. P. Wijk

IGC Proceedings (1993-2023)

Ryegrass is widely adapted to cool temperate eco-zones and breeders often submit individual varieties for testing in a number of EU countries. National testing programmes often combine data from several trial sites that may differ climatically, but not from sites in other member states, despite the possibility of high ecological similarity. Given increasing interest in ‘animal value’ characters (soluble sugars, lipids, sward geometry), additional testing for these would be valuable but is prohibited by capped or declining funding. Data sharing between EU national authorities could be advantageous but is inhibited by the lack of statistically valid data on the sensitivity …


Correlation Between Epiphytic Microflora And Microbial Pollution And Fermentation Quality Of Silage Made From Grasses, B. Osmane, J. Blūzmanis Feb 2023

Correlation Between Epiphytic Microflora And Microbial Pollution And Fermentation Quality Of Silage Made From Grasses, B. Osmane, J. Blūzmanis

IGC Proceedings (1993-2023)

Grass forage in Latvia is the main and inexpensive cow feed, however its composition and nutritive value differ during the growth period of grasses. The traits of grasses, their natural ensilage capacity, count of epiphytic microflora, the timing of harvest and ensilage making technology affecting the quality of grass silage are important issues to be studied. Silage making for the winter period is the treatment of green material to minimise the breakdown of nutrients being the results of biochemical and microbiological processes. The aim of the research was to clarify the methodologies to reduce the count of epiphytic microflora and …


Perennial Ryegrass Variety Differences In Nutritive Value Characteristics, T. J. Gilliland, R. E. Agnew, A. M. Fearson, F. E. A. Wilson Feb 2023

Perennial Ryegrass Variety Differences In Nutritive Value Characteristics, T. J. Gilliland, R. E. Agnew, A. M. Fearson, F. E. A. Wilson

IGC Proceedings (1993-2023)

Animal grazing performance at grass is predominately determined by herbage intake rates, with high yielding dairy cows requiring up to 20 kg/d DM within a limited grazing time (Gibb, 1998). Grass nutritional factors such as seasonal patterns in digestibility and water-soluble carbohydrate levels have been linked to animal productivity (Davies et al., 1991), while sward surface height, herbage mass, bulk density and green leaf mass have been shown to promote high grazing intake (Barrett et al., 2001). Furthermore, fatty acid profiles have been shown to improve the unsaturated fatty acid composition of milk, with potential human health benefits …


Management Of Pasture Quality For Sheep On New Zealand Hill Country, D. I. Gray, J. I. Reid, P. D. Kemp, I. M. Brookes, D. Horne, P. R. Kenyon, C. Matthew, S. T. Morris, I. Valentine Feb 2023

Management Of Pasture Quality For Sheep On New Zealand Hill Country, D. I. Gray, J. I. Reid, P. D. Kemp, I. M. Brookes, D. Horne, P. R. Kenyon, C. Matthew, S. T. Morris, I. Valentine

IGC Proceedings (1993-2023)

The control of pasture quality over spring is central to the achievement of high levels of sheep performance on hill country. Despite this, with the exception of the work of Lambert et al. (2000), little is known about how farmers actually manage pasture quality. The purpose of this research was to describe how a high performing hill country farmer manages pasture quality on their sheep area over spring and from this develop a framework that will assist other farmers improve their pasture management.


Production And Plant Density Of Sulla Grazed By Sheep At Three Growth Stages, H. Krishna, P. D. Kemp Feb 2023

Production And Plant Density Of Sulla Grazed By Sheep At Three Growth Stages, H. Krishna, P. D. Kemp

IGC Proceedings (1993-2023)

Sulla is one of the few temperate forage legumes that contain enough condensed tannins to improve the efficiency with which livestock use protein (Marshall et al., 1979). However, it usually is productive only for approximately 14 months in New Zealand, and little is known of its response to grazing. This paper reports on the production and persistence of Sulla cv. Necton, when using growth stage as the criterion for time of grazing by sheep in a maritime, temperate environment.


Spring Calving Suckler Beef Systems: Influence Of Grassland Management System On Herbage Availability, Utilisation, Quality And Cow And Calf Performance To Weaning, M. J. Drennan, M. Mcgee, S. Kyne, B. O'Neill Feb 2023

Spring Calving Suckler Beef Systems: Influence Of Grassland Management System On Herbage Availability, Utilisation, Quality And Cow And Calf Performance To Weaning, M. J. Drennan, M. Mcgee, S. Kyne, B. O'Neill

IGC Proceedings (1993-2023)

Suckler beef systems in Ireland are primarily based on grass. Suckler systems vary in intensity but many operate low input systems and participate in REPS (Rural Environmental Protection Scheme). As there is a considerable cost associated with second-cut silage this research compared a two-cut system with a simplified low input one-cut system.


The Importance Of Patch Size In Estimating Steady-State Bite Rate In Grazing Cattle, E. D. Ungar, N. Ravid, T. Zada, E. Ben-Moshe, R. Yonatan, S. Brenner, H. Baram, A. Genizi Feb 2023

The Importance Of Patch Size In Estimating Steady-State Bite Rate In Grazing Cattle, E. D. Ungar, N. Ravid, T. Zada, E. Ben-Moshe, R. Yonatan, S. Brenner, H. Baram, A. Genizi

IGC Proceedings (1993-2023)

Since the pioneering work of Black and Kenney (1984), various intake studies have been conducted at the spatial scale of a single feeding station ("patch") to elucidate the processes that determine instantaneous intake rate (e.g. Laca et al., 1994). While these are well-suited for patch depletion studies, it is less clear how well they represent non-patchy and relatively homogeneous environments (Ungar & Griffiths, 2002). Clearly, grazing should be restricted to the upper grazing horizon (i.e. layer of bites), but sample duration may be insufficient to characterize steady-state behaviour, especially when grazing commences on an empty mouth. We examined the …


Performance Of Meat Goats Grazing Winter Annual Grasses In The Piedmont Of The Southeastern Usa, J-M. Luginbuhl, J. P. Mueller Feb 2023

Performance Of Meat Goats Grazing Winter Annual Grasses In The Piedmont Of The Southeastern Usa, J-M. Luginbuhl, J. P. Mueller

IGC Proceedings (1993-2023)

In the Southeastern United States, meat goats (Capra hircus hircus) are becoming increasingly important contributors to the income of many small producers. Meat goats perform well in grazing situations if grazing management practices match their grazing behavior. Nevertheless, little research data are available from the region specifically directed toward forage feeding programs for goats reared for meat production. Hart et al. (1993) reported that growing Alpine, Angora and Nubian kids grazed on high quality Triticum aestivum forage gained 50 g/d, whereas Kiesling et al. (1994) reported gains ranging from 65 to 141 g/d in growing Angora …


The Effect Of Early And Delayed Spring Grazing On The Milk Production, Grazing Management And Grass Intake Of Dairy Cows, E. Kennedy, M. O'Donovan, J. P. Murphy, L. Delaby, F. P. O'Mara Feb 2023

The Effect Of Early And Delayed Spring Grazing On The Milk Production, Grazing Management And Grass Intake Of Dairy Cows, E. Kennedy, M. O'Donovan, J. P. Murphy, L. Delaby, F. P. O'Mara

IGC Proceedings (1993-2023)

Earlier access to pasture can increase the overall proportion of grazed grass in the diet of the spring calving dairy cow. Further benefits can also be achieved from early turnout, including improved animal production, increased sward utilisation and enhanced sward quality (O’Donovan et al., 2004). The objective of this study was to compare the effect of initial spring grazing date and stocking rate on the performance of spring calving dairy cows.


Intake Characteristics Of Diploid And Tetraploid Perennial Ryegrass Varieties When Grazed By Simmental X Holstein Yearling Heifers Under Rotational Stocking Management, R. J. Orr, J. E. Cook, K. L. Young, R. A. Champion, A. J. Rook Feb 2023

Intake Characteristics Of Diploid And Tetraploid Perennial Ryegrass Varieties When Grazed By Simmental X Holstein Yearling Heifers Under Rotational Stocking Management, R. J. Orr, J. E. Cook, K. L. Young, R. A. Champion, A. J. Rook

IGC Proceedings (1993-2023)

Orr et al. (2003) measured large differences in dry matter (DM) intake rate between 15 intermediate-heading perennial ryegrass varieties when they were continuously stocked with sheep and subsequently explored the extent to which, for 5 of these varieties, these differences could be explained by chemical and morphological traits (Orr et al., 2004a) which could be targeted in grass breeding programmes. Here, four of the 15 varieties, which within ploidy had low or high intake characteristics when grazed by sheep, were rotationally stocked with cattle and intake and sward factors were measured.


Optimising Financial Return From Grazing In Temperate Pastures, P. Dillon, J. R. Roche, L. Shalloo, B. Horan Feb 2023

Optimising Financial Return From Grazing In Temperate Pastures, P. Dillon, J. R. Roche, L. Shalloo, B. Horan

IGC Proceedings (1993-2023)

Key Points

  1. The increased interest in pasture-based systems of milk production in recent years has been largely generated through lower product prices and rising costs of production.

  2. Pasture based systems of milk production decrease unit production costs, through lower feed and labour expenses, and reduced capital investment.

  3. Systems utilising grazed pasture will be optimised in regions where pasture production potential is high, variability in seasonal pasture supply and quality is low, manufacturing milk accounts for a large proportion of total production, and where large areas of land are available at relatively low cost.

  4. Pasture based systems may allow greater global …


Challenges And Opportunities For Animal Production From Temperate Pastures, D. A. Clark Feb 2023

Challenges And Opportunities For Animal Production From Temperate Pastures, D. A. Clark

IGC Proceedings (1993-2023)

Key points

  1. Temperate pastures offer a major opportunity to reduce the feed costs associated with ruminant production.

  2. Pastures offer unique opportunities for producing high value components in feedstuffs that are beneficial to human health.

  3. The increased use of pasture will not automatically lead to improved environmental outcomes – difficult challenges exist in reducing nitrogen and greenhouse gas pollution.

  4. Grazed pasture systems offer advantages in animal welfare, provided management avoids the problems associated with climatic extremes, and the toxins associated with some pastures.

  5. To remain competitive with total mixed ration systems, and environmentally acceptable, pastures with higher intake characteristics that allow …


Decision Support For Temperate Grasslands: Challenges And Pitfalls, J. R. Donnelly, L. Salmon, R. D. H. Cohen, Zl. Liu, Xp. Xin Feb 2023

Decision Support For Temperate Grasslands: Challenges And Pitfalls, J. R. Donnelly, L. Salmon, R. D. H. Cohen, Zl. Liu, Xp. Xin

IGC Proceedings (1993-2023)

Key points

  1. Successful adoption of decision support tools (DS tools) to address grassland management issues requires careful attention in design to ensure ease-of-use, accuracy in prediction and the flexibility to simulate actual practices.

  2. DS tools must handle spatial variability and where possible include facilities for automatic sourcing of essential information for initialisation.

  3. Advances in the development of DS tools will depend on resolution of scientific issues in grassland biology including investment in dedicated experiments to determine parameter values for model equations.

  4. The use of mechanistic models, the integration of remote sensing technology and cooperation between research groups to develop modular …


Modelling Of Herbage Intake And Milk Production By Grazing Dairy Cows, Rémy Delagarde, M. O'Donovan Feb 2023

Modelling Of Herbage Intake And Milk Production By Grazing Dairy Cows, Rémy Delagarde, M. O'Donovan

IGC Proceedings (1993-2023)

Key-points

  1. Models predicting intake and performance of grazing ruminants from animal, sward, grazing and supplements characteristics are rare, but they are now included in several decision support systems (DSS).

  2. An evaluation of the performance and accuracy of published models are rarely undertaken by their authors, but this is proposed in this paper.

  3. There is still a need for experimental research but also for the development of generic and dynamic models to predict intake and performance over a wide range of grazing conditions.


Grass Growth Modelling: To Increase Understanding And Aid Decision Making On-Farm, P. D. Barrett, A. S. Laidlaw Feb 2023

Grass Growth Modelling: To Increase Understanding And Aid Decision Making On-Farm, P. D. Barrett, A. S. Laidlaw

IGC Proceedings (1993-2023)

Key points

  1. Crop and grass growth models have been developed over the last 50 years, or so, but general appreciation of their benefits and potential has been recognised only relatively recently. The most popular application of grass growth models has traditionally been for knowledge understanding.

  2. There is growing awareness of the potential of models in decision support systems (DSS) applications to aid pasture management and grassland budgeting on dairy farms.

  3. Although some models have been developed for DSS, their widespread uptake in industry has been slow; challenges still exist which need to be addressed in order to improve their precision …


Genetic Characteristics Required In Dairy And Beef Cattle For Temperate Grazing Systems, F. Buckley, C. Holmes, M. G. Keane Feb 2023

Genetic Characteristics Required In Dairy And Beef Cattle For Temperate Grazing Systems, F. Buckley, C. Holmes, M. G. Keane

IGC Proceedings (1993-2023)

Key points

  1. Only about 10% of the world’s milk is produced from grazing systems. Consequently the majority of dairy cattle have not been selected under grazing, nor on seasonal systems. This is not true for beef cattle, for which the majority, especially the dams, are managed under seasonal grazing systems.

  2. In grazing systems daily feed intake is limited to lower levels than are achievable on concentrate plus conserved forage rations. Consequently, cows most suited to grazing environments are likely to have a lower genetic potential for milk production than cows selected in high concentrate systems, to minimise their relative energy …