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Full-Text Articles in Agronomy and Crop Sciences
Evaluation Of Sweet Grain Sorghum Silage For Dairy Cows As An Alternative To Irrigated Maize Silage, W. G. Do Nascimento, Y. Barrière, X. Charrier, Christian Huyghe, J. C. Emile
Evaluation Of Sweet Grain Sorghum Silage For Dairy Cows As An Alternative To Irrigated Maize Silage, W. G. Do Nascimento, Y. Barrière, X. Charrier, Christian Huyghe, J. C. Emile
IGC Proceedings (1993-2023)
Under European dairy cattle rearing conditions, whole plant maize silage is the main part of the dairy cow's diet especially during the winter season. Nevertheless maize production can be limited in some areas because summer rainfall is insufficient and so irrigation is necessary. Grain sorghum hybrids, and especially sweet sorghum types, are potentially of great interest to avoid this water consumption (Lemaire et al., 1996, Legarto, 2000). For this reason we evaluated in 2003 the benefits and limits of a sweet grain sorghum silage for dairy milk production, compared to an irrigated maize silage. We paid particularl attention to …
Balancing Water Use Efficiency And Milk Production In The Sub-Tropics, Mark N. Callow, S. K. Kenman
Balancing Water Use Efficiency And Milk Production In The Sub-Tropics, Mark N. Callow, S. K. Kenman
IGC Proceedings (1993-2023)
Queensland dairy farmers have had to confront in the last 5 years deregulation of the milk pricing system, resulting in a 25% reduction in farm gate price for milk in the year 2000, and drought. Many storage dams are significantly below capacity and regulatory authorities have imposed restrictions on irrigation water allocations. Major changes in farm business strategies were needed to overcome the shortfall in milk income. Production systems had to change to deliver more milk more efficiently and become more profitable. A farmlet study was developed in the sub-tropical dairy region of Queensland to evaluate 5 very different farm …
Cap Reform And Nitrate Restrictions: Implications For Irish Grass Based Dairy Production Systems, Anne Marie Butler, M. Wallace, P. Dillon
Cap Reform And Nitrate Restrictions: Implications For Irish Grass Based Dairy Production Systems, Anne Marie Butler, M. Wallace, P. Dillon
IGC Proceedings (1993-2023)
The benefit of a systems approach to analysing production situations has long been recognised in agricultural research. The development and application of production-oriented dairy models offer tremendous capabilities for both encompassing the realities faced by producers while also considering the adaptation possibilities available to them in light of internal and external forces of change. This farm level dairy model represents one such approach. The objectives of the study were: (1) to develop a comprehensive farm-level model of Irish milk production systems and (2) to apply the model to identify optimal adaptation strategies of dairy farmers within the context of European …
Pâtur’In: A User-Friendly Software Tool To Assist Dairy Cow Grazing Management, Luc Delaby, J. L. Peyraud, P. Faverdin
Pâtur’In: A User-Friendly Software Tool To Assist Dairy Cow Grazing Management, Luc Delaby, J. L. Peyraud, P. Faverdin
IGC Proceedings (1993-2023)
The feeding of dairy cows at pasture presents many technical, economic and environmental advantages, while benefiting from a very favourable image. However, the management of grazed land is a complex game of strategy in which the farmer applies decisions in order to manage two unstable and uncertain fluxes of change: growth of grass and intake of the herd. Many tools (platemeter, etc.) and overall methods (local stocking rate references, farm cover, etc.) have been developed as aids to grazing management. Nevertheless, few decision-support systems are currently available that make it possible to anticipate and assess the consequences of a given …
Determination Of Optimal Grazing Management For Dairy Cows In Galicia (Spain) Using A Decision Support System, O. P. Vázquez Yáñez, A. González Rodríguez, J. López Díaz
Determination Of Optimal Grazing Management For Dairy Cows In Galicia (Spain) Using A Decision Support System, O. P. Vázquez Yáñez, A. González Rodríguez, J. López Díaz
IGC Proceedings (1993-2023)
GRAZEMORE is a decision support system (DSS) oriented to evaluate dairy grazing management decisions on pasture growth and milk production. The system integrates a herbage growth model (Barrett et al., 2003) and a herbage intake model (Delagarde et al., 2004) and has been validated in several EU countries. The objective of this work was to use this DSS to determine optimal grazing management of dairy cows at three supplementation levels and three grazing management strategies under Galician conditions.
Methane Emissions Of Dairy Cows In Irish Spring-Calving, Grass Based Production Systems, Frank O'Mara, D. K. Lovett
Methane Emissions Of Dairy Cows In Irish Spring-Calving, Grass Based Production Systems, Frank O'Mara, D. K. Lovett
IGC Proceedings (1993-2023)
Countries which sign up to the Kyoto Protocol on greenhouse gas emissions are required to return annual inventories of greenhouse gas emissions, including methane emissions from farm livestock. Countries with large agricultural emissions are encouraged to derive specific emission factors (annual production of methane per animal in a specified animal class) for their livestock populations, rather than relying on default emission factors provided by IPCC (1996). In this paper, we describe how an emission rate of methane from enteric fermentation for spring-calving dairy cows in Irish production systems has been derived.
Effects Of Perennial Ryegrass Cultivars On Traits For Improved Animal Performance, Harm J. Smit, B. M. Tas, Hassan Z. Taweel, J. Dijkstra, Anjo Elgersma, S. Tamminga
Effects Of Perennial Ryegrass Cultivars On Traits For Improved Animal Performance, Harm J. Smit, B. M. Tas, Hassan Z. Taweel, J. Dijkstra, Anjo Elgersma, S. Tamminga
IGC Proceedings (1993-2023)
The use of quality parameters in grass breeding is limited. There may be options to improve grass cultivars (cvs) for improved animal performance.
Effect Of Red And White Clover Added To A Rye Grass-Based Diet On Intake, Fibre Digestion And Methane Release Of Dairy Cows, Anette H. Van Dorland, Michael Kreuzer, M. Leuenberger, H. R. Wettstein
Effect Of Red And White Clover Added To A Rye Grass-Based Diet On Intake, Fibre Digestion And Methane Release Of Dairy Cows, Anette H. Van Dorland, Michael Kreuzer, M. Leuenberger, H. R. Wettstein
IGC Proceedings (1993-2023)
Forage legumes like white and red clover are widely grown in association with grass, with the intention to improve the quality of grass-based diets. However little is known about the effect of either white or red clover added to a grass-based diet on methane release, and existing studies are not conclusive. The objective of this study, applying the respiratory chamber technique, was to determine the effect of red and white clover added to a rye grass-based diet on intake, fibre digestion and methane release of dairy cows.
Influence Of Giving A Choice Of Grazing Or Maize Silage Offered In The Field Simultaneously On Diet Selection Of Lactating Dairy Cows, O. Hernández‐Mendo, J. D. Leaver
Influence Of Giving A Choice Of Grazing Or Maize Silage Offered In The Field Simultaneously On Diet Selection Of Lactating Dairy Cows, O. Hernández‐Mendo, J. D. Leaver
IGC Proceedings (1993-2023)
Changing the times of access to grazing and to maize silage (MS) offered indoors affects the relative intake of each feed, but has little effect on dairy cow performance (Hernandez-Mendo & Leaver, 2000). Offering the MS in the grazing paddock as an instantaneous alternative to grazing should give an insight into the factors influencing feed intake, and may provide a means of alleviating the high rate of decline in milk yield of grazing dairy cows. The objective of this study was to examine the response in diet preferences and performance of lactating dairy cows when grazing a perennial ryegrass sward …
Estimating Pasture Intake By Dairy Cows, Dennis R. Cosgrove, D. P. Cooper
Estimating Pasture Intake By Dairy Cows, Dennis R. Cosgrove, D. P. Cooper
IGC Proceedings (1993-2023)
Proper nutrient management planning minimizes the environmental impact of manure from dairy farms. Manure output from dairy cows can be predicted from feed intake (Wilkerson et al., 1997). Weighing feed and refusals each day can determine accurately the feed intake of dairy cows in confinement. Intake determination is more difficult for dairy cows on pasture (Vasquez & Smith, 2000). As part of a larger study aimed at estimating manure production of dairy cows on pasture, this study compares 3 methods for estimating pasture yield and feed intake.
The Use Of Forage Supplements To Overcome Seasonal Shortages Of Grazed Herbage In Dairy Production Systems, A. Hameleers, D. J. Roberts
The Use Of Forage Supplements To Overcome Seasonal Shortages Of Grazed Herbage In Dairy Production Systems, A. Hameleers, D. J. Roberts
IGC Proceedings (1993-2023)
In most dairy production systems, grazed herbage is potentially the cheapest forage resource. However, while the availability is affected by seasonal changes in herbage growth, and/or between year variations in climatic conditions, the requirements of dairy production systems tend to remain constant throughout the season. This paper summarises five experiments that examined the effect of the characteristics of the forage supplement (dry matter, DM; metabolisable energy, ME, content; Type) and the effect of stage of lactation and access method to the supplement on animal performance.
Ensiling Characteristics And Nutritive Value Of Browse/Maize Forage Mixtures, F. B. Bareeba, H. Kato, Elly N. Sabiiti
Ensiling Characteristics And Nutritive Value Of Browse/Maize Forage Mixtures, F. B. Bareeba, H. Kato, Elly N. Sabiiti
IGC Proceedings (1993-2023)
The practice of growing fodder tree and shrubs is being advocated for and adopted in smallholder dairy production systems. In Uganda, Calliandra calothyrsus, Gliricidia sepium, and Leucaena leucocephala have been identified and recommended as the most suitable species (Sabiiti, 2001). However tree foliage contains toxic compounds (Lowry, 1990), which may be alleviated by ensiling. The objective of the experiment was to study the ensiling characteristics of browse/ maize forage mixtures and their nutritive value when fed to lactating dairy cows.
Investigation Into Differences In Palatability Among Festulolium Varieties As Haylage, E. Touno, S. Kushibiki, H. Shingu, A. Oshibe
Investigation Into Differences In Palatability Among Festulolium Varieties As Haylage, E. Touno, S. Kushibiki, H. Shingu, A. Oshibe
IGC Proceedings (1993-2023)
In Japan, paddy fields that are no longer used for cultivation of rice are being converted to cultivation of forage crops. Therefore, grass with greater wet resistance and higher quality is required. Festulolium is an interspecific hybrid between the Lolium and Festuca species and combines the characteristics of high-quality ryegrass and resistance to hostile environments from fescues (Thomas & Humphreys, 1991). Among festulolium varieties, there is wide variation in environmental resistance and feeding value. One festulolium variety, Paulita, shows superior wet resistance to Evergreen and the total digestible nutrients of Evergreen was similar to that of cocksfoot (cv. Kitamidori) (Touno …
Whole Crop Cereal Silage In Dairy Production, J. Wallsten, L. Ericson, K. Martinsson
Whole Crop Cereal Silage In Dairy Production, J. Wallsten, L. Ericson, K. Martinsson
IGC Proceedings (1993-2023)
Whole-crop cereal silages (WCCS) are used to some extent in Sweden, but knowledge about the use of this feed for high yielding dairy cows is scarce. The crop is often harvested at different stages of maturity, from heading to yellow ripeness, which gives forages that differ in chemical composition. The purpose of this trial was to compare intake and milk production of dairy cows fed a WCCS based on barley harvested at three different stages of maturity.
Effect Of Potato Pulp Silage Supplementation On Milk Production In Cows Grazing Temperate Pasture, Masaaki Hanada, Y. Aibibula, D. Okumura, Meiji Okamoto
Effect Of Potato Pulp Silage Supplementation On Milk Production In Cows Grazing Temperate Pasture, Masaaki Hanada, Y. Aibibula, D. Okumura, Meiji Okamoto
IGC Proceedings (1993-2023)
In a dairy farming system based on pasture in Japan, maize grain is generally used as an energy source for milking cows, with almost all grain been imported. Potato-pulp is one of the agricultural by-products derived from the starch industry in the northern island of Japan. In our previous study (Aibibula et al., 2004), it was demonstrated that potato pulp could be preserved for a long time by ensiling without additives, and that the digestible energy value of potato pulp silage (13 MJ/kg DM) was almost the same as beet pulp. From these results, it is possible that some …
The Effects Of A High Grass Input Feeding System Compared To High Concentrate Input Feeding System Offered To Spring Calving Dairy Cows In Early Lactation, E. Kennedy, M. O'Donovan, J. P. Murphy, F. P. O'Mara, L. Delaby
The Effects Of A High Grass Input Feeding System Compared To High Concentrate Input Feeding System Offered To Spring Calving Dairy Cows In Early Lactation, E. Kennedy, M. O'Donovan, J. P. Murphy, F. P. O'Mara, L. Delaby
IGC Proceedings (1993-2023)
Grazed grass is the cheapest feed available on Irish dairy farms. The inclusion of grass in the diet of the spring-calving dairy cow in early lactation is recommended. Previous studies focused on introducing grazed herbage into the cows diet in early spring in conjunction with grass silage and concentrate, and compared this to cows fed indoors. The objective of this study was to compare the milk production and feed budget of two contrasting early lactation feeding regimes. One regime was based on a high herbage inclusion with a low concentrate level (HG), while the other was based on a high …
A Comparison Of A Full Time Grazing And A Partial Storage Feeding System, For Dairy Cows, C. P. Ferris, D. C. Patterson
A Comparison Of A Full Time Grazing And A Partial Storage Feeding System, For Dairy Cows, C. P. Ferris, D. C. Patterson
IGC Proceedings (1993-2023)
Partial storage feeding has been adopted by a number of Northern Ireland dairy farmers in recent years. This is due in part to increasing cow numbers, and as such, insufficient pasture close to the milking parlour to permit full time grazing. Partial storage feeding may also have environmental benefits, as well as reducing labour requirements associated with 'droving' and pasture management. In view of this, a study was undertaken to examine animal performance with either a full-time grazing, or a partial storage feeding regime.
The Milk Yield By Cinisara Cows In Different Management Systems: 1. Effect Of Season Of Calving, C. Giosuè, M. Alabiso, M. L. Alicata, G. Parrino
The Milk Yield By Cinisara Cows In Different Management Systems: 1. Effect Of Season Of Calving, C. Giosuè, M. Alabiso, M. L. Alicata, G. Parrino
IGC Proceedings (1993-2023)
The Cinisara cow is Sicilian autochthonous breed; the milk has very interesting qualitative characteristics (chemical, physical and technologic parameters, principally due to its high part β of K casein) and is processed to make Caciocavallo cheese. Characteristics of milk yield are influenced by exogenous factors, such as management system, lactation number and season of calving. Pastures provide the basic feed but grazing is not continuous through the year. The aim of this research was to optimize the distribution of production over the year through the study of the effect of season of calving on qualitative characteristics of milk from Cinisara …
Grazing Suitability Of Various Napier Grass Varieties In Paddocks Of Different Ages, Yasuyuki Ishii, M. M. Mukhtar, Sayan Tudsri, Sachiko Idota, Y. Nakamura, Kiichi Fukuyama
Grazing Suitability Of Various Napier Grass Varieties In Paddocks Of Different Ages, Yasuyuki Ishii, M. M. Mukhtar, Sayan Tudsri, Sachiko Idota, Y. Nakamura, Kiichi Fukuyama
IGC Proceedings (1993-2023)
Previous studies have demonstrated that late-heading type dwarf (DL) Napier grass (Pennisetum purpureum Schumach) introduced to Japan from Thailand by the Dairy Promotion Organization of Thailand was able to overwinter in the lowland areas of southern Kyushu (Mukhtar et al., 2003). The species has a higher proportion of leaf blade than other normal and dwarf varieties. These studies were conducted to assess the suitability of the various Napier grass varieties for grazing (Mukhtar et al., 2004). The objective of this study was to examine the grazing suitability, herbage quality and wintering ability of three Napier grass varieties …
A Comparison Of Perennial Ryegrass Cultivars Differing In Heading Date And Grass Ploidy For Grazing Dairy Cows At Two Different Stocking Rates, M. O'Donovan, G. Hurley, L. Delaby, G. Stakelum
A Comparison Of Perennial Ryegrass Cultivars Differing In Heading Date And Grass Ploidy For Grazing Dairy Cows At Two Different Stocking Rates, M. O'Donovan, G. Hurley, L. Delaby, G. Stakelum
IGC Proceedings (1993-2023)
Animal productivity is the ultimate performance indicator of any new grass cultivar. Direct assessment is complex and expensive. Recent research has identified a number of important sward factors that influence intake and production. The most important factor appears to be green leaf mass. The objective of this two year study was to investigate the effects on milk yield, composition and grass intake of grass cultivars with contrasting heading dates (HD) and grass ploidies (PL) when grazed at different stocking rates.
Does The Feeding Behaviour Of Dairy Cows Differ When Fed Ryegrass Indoors Vs. Grazing?, A. V. Chaves, A. Boudon, J. L. Peyraud, R. Delagarde
Does The Feeding Behaviour Of Dairy Cows Differ When Fed Ryegrass Indoors Vs. Grazing?, A. V. Chaves, A. Boudon, J. L. Peyraud, R. Delagarde
IGC Proceedings (1993-2023)
Dairy cows eating ryegrass ingest smaller boli when grazing than when fed indoors (93 vs. 142 g; Boudon et al., 2004). To investigate whether this difference in bolus affects feeding behaviour of the cows, an automated system (chewing halters) was used to monitor feeding behaviour of cows given ad libitum access to perennial ryegrass in individual feed troughs (indoor feeding, IF) or at pasture (grazing, GR).
Variation Between Individuals In Voluntary Intake And Herbage Intake Of Grazing Dairy Cows, H. M. N. Ribeiro Filho, R. Delagarde, L. Delaby, J. L. Peyraud
Variation Between Individuals In Voluntary Intake And Herbage Intake Of Grazing Dairy Cows, H. M. N. Ribeiro Filho, R. Delagarde, L. Delaby, J. L. Peyraud
IGC Proceedings (1993-2023)
Herbage intake and milk yield of unsupplemented grazing dairy cows are highly variable between animals within a herd (Delaby et al., 2001). The objective of this experiment was to describe the relationship between the individual voluntary intake (VI) of dairy cows measured before turnout and their herbage intake at grazing, at two herbage allowances.
The Meal Criterion Estimated In Grazing Dairy Cattle: Evaluation Of Different Methods, P. A. Abrahamse, D. Reynaud, J. Dijkstra, S. Tamminga
The Meal Criterion Estimated In Grazing Dairy Cattle: Evaluation Of Different Methods, P. A. Abrahamse, D. Reynaud, J. Dijkstra, S. Tamminga
IGC Proceedings (1993-2023)
The meal criterion (MC) has been found a useful tool to pre-treat intake behaviour data in dairy cows. It was defined as the longest interval between bouts that belong to the same meal (Tolkamp & Kyriazakis, 1999), necessary to cluster bouts to meals. The method of Yeates et al. (2001) calculating the loge-transformed intervals between bouts and using the Gaussian-Gaussian-Weibull (GGW) model to calculate the MC was found to provide the best estimation of the MC in biological as well as statistical terms. However, in grazing dairy cattle the MC-estimation has only been carried out by Rook …
Pâtur’In: A User-Friendly Software Tool To Assist Dairy Cow Grazing Management, L. Delaby, J. L. Peyraud, P. Faverdin
Pâtur’In: A User-Friendly Software Tool To Assist Dairy Cow Grazing Management, L. Delaby, J. L. Peyraud, P. Faverdin
IGC Proceedings (1993-2023)
The feeding of dairy cows at pasture presents many technical, economic and environmental advantages, while benefiting from a very favourable image. However, the management of grazed land is a complex game of strategy in which the farmer applies decisions in order to manage two unstable and uncertain fluxes of change: growth of grass and intake of the herd. Many tools (platemeter, etc.) and overall methods (local stocking rate references, farm cover, etc.) have been developed as aids to grazing management. Nevertheless, few decision-support systems are currently available that make it possible to anticipate and assess the consequences of a given …
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
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 (1993-2023)
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).
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
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 (1993-2023)
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.
Effect Of Farm Grass Cover At Turnout On The Grazing Management Of Spring Calving Dairy Cows, M. O'Donovan, L. Delaby, P. Defrance
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 (1993-2023)
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.
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
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 (1993-2023)
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 …
The Effect Of Chop Length And Additive On Silage Intake And Milk Production In Cows, V. Toivonen, T. Heikkilä
The Effect Of Chop Length And Additive On Silage Intake And Milk Production In Cows, V. Toivonen, T. Heikkilä
IGC Proceedings (1993-2023)
Effects of reduced silage chop length on silage intake and milk production by dairy cows have been variable. Chopping of grass at harvest generally improves silage fermentation quality and consequently intake. The objective of this study was to assess the effect of chopping flail harvested silage ensiled with acid or biological additive prior to feeding on intake, milk yield and milk composition in dairy cows.
Feeding Mixed Grass-Clover Silages With Elevated Sugar Contents To Dairy Cows, J. Bertilsson
Feeding Mixed Grass-Clover Silages With Elevated Sugar Contents To Dairy Cows, J. Bertilsson
IGC Proceedings (1993-2023)
Grasses with high sugar content (WSC) have been claimed to increase feed intake and milk production and at the same time give more efficient N utilisation and thus reduce pollution (e.g. Miller et al., 2001). In an ongoing EU-supported project (“Sweetgrass”), we have grown the new varieties of perennial ryegrasses and fed them to dairy cows. Results from the first year’s experiment when pure ryegrass silages made from standard or high-sugar varieties were fed, showed small differences in feed intake, milk production and N partitioning. In order to test the principle, it was therefore decided to increase the difference …