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Articles 16711 - 16740 of 302420

Full-Text Articles in Physical Sciences and Mathematics

Analysis Of Silage Fermentation Characteristics Using Transflectance Measurements By Near Infrared Spectroscopy, A. Martínez, A. Soldado, R. Garcia, D. Sánchez, B. De La Roza-Delgado Feb 2023

Analysis Of Silage Fermentation Characteristics Using Transflectance Measurements By Near Infrared Spectroscopy, A. Martínez, A. Soldado, R. Garcia, D. Sánchez, B. De La Roza-Delgado

IGC Proceedings (1993-2023)

The fermentation end products as lactic acid, volatile fatty acids and ammonia-nitrogen, are important indicators of the efficiency of silage fermentation and are closely related to nutritive value of them (Jaster, 1995). Drying is problematic in the case of silage as many fermentation products are volatile and may get lost during the drying process. This may be a reason why NIR technology is being little used for the evaluation of silage fermentation characteristics. The feasibility of using near infrared transflectance spectroscopy to evaluate the content in fermentation end products of grass and maize fresh silage was investigated in this study.

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A Simple Method For The Correction Of Fermentation Losses Measured In Laboratory Silos, F. Weissbach Feb 2023

A Simple Method For The Correction Of Fermentation Losses Measured In Laboratory Silos, F. Weissbach

IGC Proceedings (1993-2023)

Dry matter (DM) losses caused by formation of gaseous fermentation products can be measured by different methods. The most common method (A) is measuring the difference between the DM input and output of a silo. Other methods are based on the measurement of the fermentation gases which spontaneously leave the silo, either directly by collecting them (B) in a special absorbent like KOH or, much more easily, by weighing the filled silo at the beginning and the end of the fermentation process (C). The figures obtained by B and C are substantially smaller than those by A. This difference represents …

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Development Of A Method For The Fast And Complete Assessment Of Quality Characteristics In Undried Grass Silages By Means Of An Nir-Diode Array Spectrometer, H. Gibaud, C. Paul, J. M. Greef, B. Ruser Feb 2023

Development Of A Method For The Fast And Complete Assessment Of Quality Characteristics In Undried Grass Silages By Means Of An Nir-Diode Array Spectrometer, H. Gibaud, C. Paul, J. M. Greef, B. Ruser

IGC Proceedings (1993-2023)

Traditionally, the determination of grass silage is very time consuming and needs a lot of manpower and chemicals. The advantages of conventional laboratory NIRS instruments are well known but their disadvantage lies in their lacking suitability for on-farm use. A new type of spectrometer based on diode arrays may be used for this purpose. However, these new instruments still need to be calibrated for an accurate estimate of the fermentative and nutritive value of wet and unchopped grass silage.

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Prediction Of Red Clover Content In Mixed Swards By Near-Infrared Reflectance Spectroscopy, B. Deprez, D. Stilmant, C. Clément, C. Decamps, A. Peeters Feb 2023

Prediction Of Red Clover Content In Mixed Swards By Near-Infrared Reflectance Spectroscopy, B. Deprez, D. Stilmant, C. Clément, C. Decamps, A. Peeters

IGC Proceedings (1993-2023)

Because of the legume fixation capacity, their high protein content, digestibility and intake characteristics, more and more attention is paid to grassland clover content. In field experiments, clover content must often be determined, for example to quantify nitrogen flux or the best practices to manage such species (Stilmant et al., 2004). However hand sorting of clover and grass, even if accurate, is time-consuming and has a high labour cost. In comparison, accuracy of visual estimation of clover content, directly in the field, varies according to training and experience. Near-infrared reflectance spectroscopy (NIRS) has been proposed as a method for …

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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 Feb 2023

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.

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Intake And Milk Production Of Lactating Dairy Cows Grazing Diverse Forage Mixtures Over Two Grazing Seasons, K. Soder, M. A. Sanderson, J. L. Stack, L. Muller Feb 2023

Intake And Milk Production Of Lactating Dairy Cows Grazing Diverse Forage Mixtures Over Two Grazing Seasons, K. Soder, M. A. Sanderson, J. L. Stack, L. Muller

IGC Proceedings (1993-2023)

Voluntary intake and stocking rate are key determinants of animal performance on pasture. Greater plant diversity in grassland plant communities has been linked to increased primary production, greater stability in response to disturbance, and reduced weed pressure. Thus, increasing plant diversity may be one approach to improving animal productivity. An experiment was conducted to determine the effects of forage diversity on intake and milk production of lactating dairy cows over two grazing seasons.

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In Situ Rumen Degradability Of Perennial Ryegrass Cultivars Differing In Ploidy And Heading Date In Ireland, V. Olsson, J. J. Murphy, F. P. O'Mara, M. O'Donovan, F. J. Mulligan Feb 2023

In Situ Rumen Degradability Of Perennial Ryegrass Cultivars Differing In Ploidy And Heading Date In Ireland, V. Olsson, J. J. Murphy, F. P. O'Mara, M. O'Donovan, F. J. Mulligan

IGC Proceedings (1993-2023)

Grazed grass is the predominant feed in Irish dairy and beef cattle production systems. Knowledge of the degradability characteristics of protein in Irish forages is necessary for the establishment of protein values (PDIE and PDIN values) for these. This knowledge would also facilitate more accurate formulation of supplements for grass diets with the potential to reduce nitrogen (N) excretion.

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Grazing Behaviour Of Beef Steers Grazing Kentucky 31 Endophyte Infected Tall Fescue, Q4508-Ar542 Novel Endophyte Tall Fescue, And Lakota Prairie Grass, H. T. Boland, G. Scaglia, J. P. Fontenot, A. O. Abaye, R. Smith Feb 2023

Grazing Behaviour Of Beef Steers Grazing Kentucky 31 Endophyte Infected Tall Fescue, Q4508-Ar542 Novel Endophyte Tall Fescue, And Lakota Prairie Grass, H. T. Boland, G. Scaglia, J. P. Fontenot, A. O. Abaye, R. Smith

IGC Proceedings (1993-2023)

Tall fescue is the most dominant grass used for pasture in the U.S. covering over 14 million ha. As a result, fescue toxicosis is a major concern among producers, especially during the summer months when the symptoms, such as reduced weight gains, are most pronounced. Producers need alternative forages for grazing cattle that do not have the negative effects associated with endophyte infected tall fescue. The objective of this experiment was to determine the grazing behaviour of cattle on Kentucky 31 endophyte infected (E+) tall fescue (Festuca arundinacea Schreb.), Q4508-AR542 (Q) novel endophyte tall fescue, and Lakota (L) …

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Caucasian Clover Is More Productive Than White Clover In Temperate Pastures, A. D. Black, D. J. Moot, R. J. Lucas Feb 2023

Caucasian Clover Is More Productive Than White Clover In Temperate Pastures, A. D. Black, D. J. Moot, R. J. Lucas

IGC Proceedings (1993-2023)

White clover (wc) (Trifolium repens) is present and is often the dominant legume in the >11 m ha of grassland in New Zealand (NZ). However, wc has limitations and normally contributes less than 20% of total annual pasture dry matter (DM) production. The use of a wider range of legume species is one way to increase legume percentage in wc/grass pastures. Caucasian (Cc) or Kura clover (Trifolium ambiguum) is a persistent legume which is slower to establish than wc but can increase total legume production (Cc plus volunteer wc) and hence N2 fixation and animal productivity. …

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Response Of Warm-Season Grass Pasture To Grazing Period And Recovery Period Lengths, B. E. Anderson, W. H. Schacht Feb 2023

Response Of Warm-Season Grass Pasture To Grazing Period And Recovery Period Lengths, B. E. Anderson, W. H. Schacht

IGC Proceedings (1993-2023)

Grazing period and recovery period lengths are key variables influencing grassland production and composition. Systems with short grazing periods and lengthy recovery periods require numerous pastures. Relatively high facility and management costs associated with multiple-pasture systems can be justified only if plant response is favorable and/or if livestock production is improved. This study determined the effects of 4 different combinations of grazing period/recovery period lengths on percentage basal cover (PBC) and relative species composition (RSC) of seeded, warm-season grass pasture.

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Yield Components In A Signal Grass-Clitoria Mixture Grazed At Different Herbage Allowance, R. Jiménez-Guillen, S. Rojas-Hernández, J. Olivares-Pérez, A. Martínez-Hernández, J. Pérez-Pérez Feb 2023

Yield Components In A Signal Grass-Clitoria Mixture Grazed At Different Herbage Allowance, R. Jiménez-Guillen, S. Rojas-Hernández, J. Olivares-Pérez, A. Martínez-Hernández, J. Pérez-Pérez

IGC Proceedings (1993-2023)

A Signal grass-Clitoria mixture provides good quality forage in the dry tropic of southern Mexico. However, its response in leaf and stem yields to grazing at different daily herbage allowances is not well documented. The objective of this study was to determine available and residual leaf and stem yields in a Signal grass (Brachiaria decumbens)-Clitoria (Clitoria ternatea) mixture grazed at different daily herbage allowance.

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Renovation-Year Forage Quality Of Grass Pastures Sod-Drilled With Kura Clover, P. R. Peterson, P. Seguin, G. Laberge, C. C. Sheaffer Feb 2023

Renovation-Year Forage Quality Of Grass Pastures Sod-Drilled With Kura Clover, P. R. Peterson, P. Seguin, G. Laberge, C. C. Sheaffer

IGC Proceedings (1993-2023)

Including legumes can enhance yield, quality, and animal performance potential of grass pastures. Kura clover is an exceptionally winter hardy forage legume with high forage quality (Taylor & Smith, 1998). However, its seedling vigor is poor. Herbicide sod suppression prior to sod drilling enabled kura clover to establish in the north central USA and eastern Canada (Cuomo et al., 2001; Laberge et al., 2005), but its percentage of renovation-year forage yield was less than for sod-seeded red or white clover. The objective of this study was to determine the influence of herbicide suppression and clover species on renovation-year …

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Forage Yield And Quality Of Signal Grass-Clitoria Mixture Grazed At Different Frequencies, R. Jiménez-Guillen, J. Olivares-Pérez, S. Rojas-Hernández, A. Martínez-Hernández Feb 2023

Forage Yield And Quality Of Signal Grass-Clitoria Mixture Grazed At Different Frequencies, R. Jiménez-Guillen, J. Olivares-Pérez, S. Rojas-Hernández, A. Martínez-Hernández

IGC Proceedings (1993-2023)

A Signal grass-Clitoria mixture provides good quality forage in the dry tropic of southern Mexico. Grazing frequency is a management tool that determines yield, botanical components and quality of pastures. The objective of this study was to determine forage yield, quality and botanical components in a Signal grass (Brachiaria decumbens)-Clitoria (Clitoria ternatea) mixture when grazed at different frequencies.

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Farm Performance From Holstein-Friesian Cows Of Three Genetic Strains On Grazed Pasture, K. A. Macdonald, B. S. Thorrold, C. B. Glassey, J. A. S. Lancaster, G. A. Verkerk, J. E. Pryce, C. W. Holmes Feb 2023

Farm Performance From Holstein-Friesian Cows Of Three Genetic Strains On Grazed Pasture, K. A. Macdonald, B. S. Thorrold, C. B. Glassey, J. A. S. Lancaster, G. A. Verkerk, J. E. Pryce, C. W. Holmes

IGC Proceedings (1993-2023)

Dairy selection objectives and farm production systems in USA and Europe are different from those in New Zealand (NZ). The use of overseas semen in NZ in the last 20 years has changed the genetics of the former NZ Holstein-Friesian (HF) strain. This trial was designed to demonstrate the genetic progress in the NZ HF dairy herd in the last 25 years and how high production potential North American HF cows perform under pasture-based feeding systems.

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Genetic Alternatives For Dairy Producers Who Practise Grazing, H. D. Norman, J. R. Wright, R. L. Powell Feb 2023

Genetic Alternatives For Dairy Producers Who Practise Grazing, H. D. Norman, J. R. Wright, R. L. Powell

IGC Proceedings (1993-2023)

The decline in cow fertility has had a negative impact on all dairy producers, especially those that practise seasonal calving with pasture-based dairying. One alternative that is being tried in the United States (US) by a few graziers is to use bulls from New Zealand (NZ) because NZ producers have practised seasonal calving for some time. However, genotype-environment interaction is a concern; genetic correlations that were derived by the International Bull Evaluation Service (2004) between bull rankings from different countries were often lower for NZ than for other countries. The objective of this study was to compare the performance of …

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Suitability Of Small And Large Size Dairy Cows In A Pasture-Based Production System, M. Steiger Burgos, R. Petermann, P. Hofstetter, P. Thomet, S. Kohler, A. Munger, J. W. Blum, P. Kunz Feb 2023

Suitability Of Small And Large Size Dairy Cows In A Pasture-Based Production System, M. Steiger Burgos, R. Petermann, P. Hofstetter, P. Thomet, S. Kohler, A. Munger, J. W. Blum, P. Kunz

IGC Proceedings (1993-2023)

Pasture-based dairy production with greatly reduced supplemental feeding and block-calving in spring is increasingly applied in Switzerland. The prevalent cow type has been selected mainly for high individual production in a barn feeding system with balanced diet. This cow type has continuously increased in size over the last 30 years. The question arises whether this type is suitable for the new system, and particularly if cow size is a critical factor. Theoretically a large, heavy type of cow has a higher intake capacity, while the nutrient requirements for a small, light type are easier to satisfy.

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Effect Of Stocking Rate And Grazing System On Fine And Superfine Merino Wool Production And Quality On Native Swards Of Uruguay, I. De Barbieri, F. Montossi, E. J. Berretta, A. Dighiero, A. Mederos Feb 2023

Effect Of Stocking Rate And Grazing System On Fine And Superfine Merino Wool Production And Quality On Native Swards Of Uruguay, I. De Barbieri, F. Montossi, E. J. Berretta, A. Dighiero, A. Mederos

IGC Proceedings (1993-2023)

Modern textile tendencies show that consumers prefer light, soft, resistant, natural, and comfortable clothes, for which fine and superfine wools are in great demand, particularly at the high value markets (Whiteley, 2003). The main objective of the present study was to define sustainable stocking rates and grazing systems on native swards for fine and superfine wool production in the Basaltic region of Uruguay.

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The Effect Of Stocking Rate And Lamb Grazing System On Sward Performance Of Trifolium Repens And Lotus Corniculatus In Uruguay, F. Montossi, R. San Julián, M. Nolla, M. Camesasca, F. Preve Feb 2023

The Effect Of Stocking Rate And Lamb Grazing System On Sward Performance Of Trifolium Repens And Lotus Corniculatus In Uruguay, F. Montossi, R. San Julián, M. Nolla, M. Camesasca, F. Preve

IGC Proceedings (1993-2023)

Lambs have a great potential to diversify and stimulate meat and wool production and economical returns within the industry. The main objective of this study was to evaluate different feeding and management alternatives for the production of high quality wool and meat as well as their effects on sward characteristics in the Basaltic region of Uruguay.

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Cattle And Sheep Mixed Grazing 1: Species Equivalence, R. D. Améndola-Massiotti, S. J. C. González-Montagna, P. A. Martínez-Hernández Feb 2023

Cattle And Sheep Mixed Grazing 1: Species Equivalence, R. D. Améndola-Massiotti, S. J. C. González-Montagna, P. A. Martínez-Hernández

IGC Proceedings (1993-2023)

The effects of mixed grazing of cattle and sheep depend on stocking rate (SR) and species ratio (Nicol, 1997). Calculations of SR and species ratio require the use of species equivalence. Equivalents are often estimated in terms of intake requirements calculated on the basis of LW0.75. Freer (1981) stated that LW0.9 would be more appropriate for comparisons of intake requirements for maintenance of sheep and cattle. Nonetheless, Nolan & Connolly (1977) stated that the equivalence is system-specific and depends on the species being considered. The objective of this experiment was to estimate species equivalence for the evaluation …

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Effect Of Strain Of Holstein-Friesian Cow And Feed System On Reproductive Performance In Seasonal-Calving Milk Production Systems Over Four Years, B. Horan, J. F. Mee, M. Rath, P. O'Connor, P. Dillon Feb 2023

Effect Of Strain Of Holstein-Friesian Cow And Feed System On Reproductive Performance In Seasonal-Calving Milk Production Systems Over Four Years, B. Horan, J. F. Mee, M. Rath, P. O'Connor, P. Dillon

IGC Proceedings (1993-2023)

In Ireland most dairy farms operate seasonal calving grass-based milk production systems. Feed demand and supply are matched by having calving highly concentrated in spring. This requires high pregnancy rates within a short time following the start of mating in late April or early May, but has become increasingly difficult to achieve due to declining fertility in Irish dairy herds (Mee, 2004). In New Zealand, cows of North American Holstein-Friesian origin have poorer fertility than New Zealand Holstein-Friesians on pasture-based seasonal calving systems (Harris & Kolver, 2001). The present study sought to determine the effect of strain of Holstein-Friesian (HF) …

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Cattle And Sheep Mixed Grazing: 2: Competition, R. D. Améndola-Massiotti, P. A. Martínez-Hernández, R. D. Améndola-Massiotti Feb 2023

Cattle And Sheep Mixed Grazing: 2: Competition, R. D. Améndola-Massiotti, P. A. Martínez-Hernández, R. D. Améndola-Massiotti

IGC Proceedings (1993-2023)

The outcome of mixed grazing depends on the degrees of complementarity and competition between animal species. Complementarity increases the utilisation of herbage resource but competition may be desirable when one grazing species has a higher priority ranking in the farming system. A species wins in the competition by harvesting a higher proportion of the available herbage than the other (Nicol, 1997). De Wit (1960) used the replacement series based on degrees of substitution of species, for the quantification of the outcome of mixtures experiments. The use of species equivalence is required in order to apply this approach to the analysis …

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Pasture Intake And Milksolids Production Of Different Strains Of Holstein-Friesian Dairy Cows, J. L. Rossi, K. A. Macdonald, B. S. Thorrold, C. Holmes Feb 2023

Pasture Intake And Milksolids Production Of Different Strains Of Holstein-Friesian Dairy Cows, J. L. Rossi, K. A. Macdonald, B. S. Thorrold, C. Holmes

IGC Proceedings (1993-2023)

Cows of high yield potential require high daily dry matter intakes (DMI) to meet their increased energy demand. For this reason, DMI may be constrained in a pasture-based system. Daily milksolids yield and DMI of three strains of Holstein-Friesian dairy cows farmed at low and high feeding level during season 2002- 2003 are reported.

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Does The Feeding Behaviour Of Dairy Cows Differ When Fed Ryegrass Indoors Vs. Grazing?, A. V. Chaves, A. Boudon, J. L. Peyraud, R. Delagarde Feb 2023

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).

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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 Feb 2023

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.

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Relationships Between Traits Other Than Production And Longevity In New Zealand Dairy Cows, D. P. Berry, B. L. Harris, A. M. Winkelman, W. Montgomerie Feb 2023

Relationships Between Traits Other Than Production And Longevity In New Zealand Dairy Cows, D. P. Berry, B. L. Harris, A. M. Winkelman, W. Montgomerie

IGC Proceedings (1993-2023)

Reduced longevity in dairy cattle is recognised world-wide to be a considerable cost to the dairy industry, especially in seasonal calving grazing production environments. The objective of the present study was to investigate the relationships among traits other than production (TOP) and true and functional longevity in purebred and crossbred New Zealand cows from commercial herds operating seasonal calving grass-based systems of milk production. This study made use of survival analysis, a technique used to allow the inclusion of incomplete (i.e., censored) longevity data in the analysis while simultaneously accounting for the skewed distribution of longevity data and the changing …

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Modelling The Effect Of Breakeven Date In Spring Rotation Planner On Production And Profit Of A Pasture-Based Dairy System, P. C. Beukes, B. S. Thorrold, M. E. Wastney, C. C. Palliser, G. Levy, X. Chardon Feb 2023

Modelling The Effect Of Breakeven Date In Spring Rotation Planner On Production And Profit Of A Pasture-Based Dairy System, P. C. Beukes, B. S. Thorrold, M. E. Wastney, C. C. Palliser, G. Levy, X. Chardon

IGC Proceedings (1993-2023)

The breakeven date is the expected date when pasture supply exceeds cow demand. This date is used to plan the rotation rates, slow during the winter, when pasture growth is low and cows are dry, to a fast rotation in spring, when growth is accelerating and most cows lactating. This date is influenced by regional climate, mainly rainfall and soil temperature, which affects timing and rate of growth acceleration. The objective of this modeling exercise was to explore the effect of the breakeven date on milksolids (MS), grass silage, farm cover and economic farm surplus (EFS) over different climate years …

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Development Of A Model Simulating The Impact Of Management Strategies On Production From Beef Cattle Farming Systems Based On Permanent Pasture, M. Jouven, R. Baumont Feb 2023

Development Of A Model Simulating The Impact Of Management Strategies On Production From Beef Cattle Farming Systems Based On Permanent Pasture, M. Jouven, R. Baumont

IGC Proceedings (1993-2023)

Grazing systems in Europe increasingly have to meet environmental objectives, which influence management strategies. A deterministic model describing farming system dynamics is being developed in order to elucidate interactions between nature-friendly management practices, as for example late (after flowering) hay harvest or moderate stocking rate, and agricultural output.

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Intake By Lactating Goats Browsing On Mediterranean Shrubland, M. Decandia, G. Pinna, A. Cabiddu, G. Molle Feb 2023

Intake By Lactating Goats Browsing On Mediterranean Shrubland, M. Decandia, G. Pinna, A. Cabiddu, G. Molle

IGC Proceedings (1993-2023)

In Mediterranean regions goat feeding systems are mainly based on shrubland that contain a wide variety of species. There are only a few equations for predicting feed intake of stall-fed goats (Luo et al., 2004). The objective of this study was to develop a model for predicting the intake of lactating goats browsing on Mediterranean shrubland.

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Adapting The Cropgro Model To Predict Growth And Perennial Nature Of Bahiagrass, S. J. Rymph, K. J. Boote, J. W. Jones Feb 2023

Adapting The Cropgro Model To Predict Growth And Perennial Nature Of Bahiagrass, S. J. Rymph, K. J. Boote, J. W. Jones

IGC Proceedings (1993-2023)

The objective of this research was to modify an existing crop growth model for ability to predict growth and composition of bahiagrass (Paspalm notatum Flügge) in response to daily weather and management inputs. The CROPGRO–CSM cropping systems model has a generic, process-oriented structure that allows inclusion of new species and simulating cropping sequences and crop rotations. An early adaptation of CROPGRO-CSM “species files” for bahiagrass over-predicted growth during late fall through early spring, and totally failed in re-growth if all foliage was lost from freeze damage. Revised species parameters and use of “pest damage” offered only a partial solution. …

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The Impact Of Concentrate Price On The Utilization Of Grazed And Conserved Grass, P. Crosson, P. O'Kiely, F. P. O'Mara, M. J. Drennan, M. Wallace Feb 2023

The Impact Of Concentrate Price On The Utilization Of Grazed And Conserved Grass, P. Crosson, P. O'Kiely, F. P. O'Mara, M. J. Drennan, M. Wallace

IGC Proceedings (1993-2023)

A linear programming model was designed and constructed to facilitate the identification of optimal beef production systems under varying technical and policy scenarios. The model operates at a systems level and most activities that could occur in Irish spring-calving, suckler beef production systems are included. In this paper, the components of the model are described together with a simple application of the model involving changing concentrate prices.

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