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- Grazing (66)
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Articles 1471 - 1500 of 1788
Full-Text Articles in Agronomy and Crop Sciences
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
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 (1977-2023)
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) …
Caucasian Clover Is More Productive Than White Clover In Temperate Pastures, A. D. Black, D. J. Moot, R. J. Lucas
Caucasian Clover Is More Productive Than White Clover In Temperate Pastures, A. D. Black, D. J. Moot, R. J. Lucas
IGC Proceedings (1977-2023)
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. …
Response Of Warm-Season Grass Pasture To Grazing Period And Recovery Period Lengths, B. E. Anderson, W. H. Schacht
Response Of Warm-Season Grass Pasture To Grazing Period And Recovery Period Lengths, B. E. Anderson, W. H. Schacht
IGC Proceedings (1977-2023)
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.
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
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 (1977-2023)
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.
Renovation-Year Forage Quality Of Grass Pastures Sod-Drilled With Kura Clover, P. R. Peterson, P. Seguin, G. Laberge, C. C. Sheaffer
Renovation-Year Forage Quality Of Grass Pastures Sod-Drilled With Kura Clover, P. R. Peterson, P. Seguin, G. Laberge, C. C. Sheaffer
IGC Proceedings (1977-2023)
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 …
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
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 (1977-2023)
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.
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
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 (1977-2023)
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.
Genetic Alternatives For Dairy Producers Who Practise Grazing, H. D. Norman, J. R. Wright, R. L. Powell
Genetic Alternatives For Dairy Producers Who Practise Grazing, H. D. Norman, J. R. Wright, R. L. Powell
IGC Proceedings (1977-2023)
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 …
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
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 (1977-2023)
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.
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
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 (1977-2023)
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.
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
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 (1977-2023)
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.
Cattle And Sheep Mixed Grazing 1: Species Equivalence, R. D. Améndola-Massiotti, S. J. C. González-Montagna, P. A. Martínez-Hernández
Cattle And Sheep Mixed Grazing 1: Species Equivalence, R. D. Améndola-Massiotti, S. J. C. González-Montagna, P. A. Martínez-Hernández
IGC Proceedings (1977-2023)
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 …
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
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 (1977-2023)
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) …
Cattle And Sheep Mixed Grazing: 2: Competition, R. D. Améndola-Massiotti, P. A. Martínez-Hernández, R. D. Améndola-Massiotti
Cattle And Sheep Mixed Grazing: 2: Competition, R. D. Améndola-Massiotti, P. A. Martínez-Hernández, R. D. Améndola-Massiotti
IGC Proceedings (1977-2023)
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 …
Pasture Intake And Milksolids Production Of Different Strains Of Holstein-Friesian Dairy Cows, J. L. Rossi, K. A. Macdonald, B. S. Thorrold, C. Holmes
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 (1977-2023)
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.
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 (1977-2023)
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 (1977-2023)
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.
Relationships Between Traits Other Than Production And Longevity In New Zealand Dairy Cows, D. P. Berry, B. L. Harris, A. M. Winkelman, W. Montgomerie
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 (1977-2023)
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 …
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
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 (1977-2023)
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 …
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
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 (1977-2023)
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.
Intake By Lactating Goats Browsing On Mediterranean Shrubland, M. Decandia, G. Pinna, A. Cabiddu, G. Molle
Intake By Lactating Goats Browsing On Mediterranean Shrubland, M. Decandia, G. Pinna, A. Cabiddu, G. Molle
IGC Proceedings (1977-2023)
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.
Adapting The Cropgro Model To Predict Growth And Perennial Nature Of Bahiagrass, S. J. Rymph, K. J. Boote, J. W. Jones
Adapting The Cropgro Model To Predict Growth And Perennial Nature Of Bahiagrass, S. J. Rymph, K. J. Boote, J. W. Jones
IGC Proceedings (1977-2023)
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. …
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
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 (1977-2023)
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.
Modelling Urine Nitrogen Production And Leaching Losses For Pasture-Based Dairying Systems, I. M. Brookes, D. J. Horne
Modelling Urine Nitrogen Production And Leaching Losses For Pasture-Based Dairying Systems, I. M. Brookes, D. J. Horne
IGC Proceedings (1977-2023)
Urine from dairy cattle grazing pastures with high crude protein (CP) concentrations is a major source of N lost in drainage water from New Zealand farms. This paper provides predictions of urinary N leaching losses for a range of stocking rates and levels of supplementation.
A Model To Evaluate Buying And Selling Policies For Growing Lambs On Pasture, P. C. H. Morel, B. Wildbore, I. M. Brookes, P. R. Kenyon, R. W. Purchas, S. Ramaswami
A Model To Evaluate Buying And Selling Policies For Growing Lambs On Pasture, P. C. H. Morel, B. Wildbore, I. M. Brookes, P. R. Kenyon, R. W. Purchas, S. Ramaswami
IGC Proceedings (1977-2023)
In pastoral sheep finishing systems, farmers aim to maximize profitability by deciding on when and how many animals to buy and/or sell, while taking into account feed availability and current prices. This paper describes a stochastic lamb growth simulation model with a set of heuristic rules, which has been developed to financially evaluate different management strategies for growing lambs on pasture.
Sensitivity Analysis Of A Growth Simulation For Finishing Lambs, P. C. H. Morel, B. Wildbore, I. M. Brookes, P. R. Kenyon, R. W. Purchas, S. Ramaswami
Sensitivity Analysis Of A Growth Simulation For Finishing Lambs, P. C. H. Morel, B. Wildbore, I. M. Brookes, P. R. Kenyon, R. W. Purchas, S. Ramaswami
IGC Proceedings (1977-2023)
A stochastic lamb growth simulation model with a set of heuristic rules has been developed to evaluate management strategies for a solely pastoral grazing system in New Zealand (Morel et al., 2005). In the present paper the results of a sensitivity analysis for this model are presented.
Modelling Winter Grass Growth And Senescence, D. Hennessy, S. Laidlaw, M. O'Donovan, P. French
Modelling Winter Grass Growth And Senescence, D. Hennessy, S. Laidlaw, M. O'Donovan, P. French
IGC Proceedings (1977-2023)
In temperate climates, because net grass growth in winter is low, most grass growth models deal with the main growing season (Mar-Oct in the N Hemisphere), with little emphasis on grass growth in winter (Nov-Feb). However, grass tissue turns over continuously (Hennessy et al., 2004) and the fate of herbage entering the winter is important in extended grazing season systems. This study aimed to model winter grass growth for the period 15 Oct 2001 to 28 Jan 2002 for a range of autumn closing dates (1 Sep, 20 Sep and 10 Oct) by modifying an existing model, so that …
Effect Of Nitrogen On The Radiation Use Efficiency For Modelling Grass Growth, R. Lambert, A. Peeters
Effect Of Nitrogen On The Radiation Use Efficiency For Modelling Grass Growth, R. Lambert, A. Peeters
IGC Proceedings (1977-2023)
When nitrogen (N) is not at a sufficient level to permit maximum growth rate, dry matter production is reduced. Models of plant growth in relation to solar radiation intercepted by the crop have been largely used. According to these models, N deficiency can act on the leaf extension and thus on the quantity of radiation intercepted by the crop, but also by reducing the radiation use efficiency of the crop (RUE) (Bélanger, 1990). The effect of N on the RUE of ryegrass swards is determined and discussed.
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 (1977-2023)
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 …
Radiation Use Efficiency Of Ryegrass: Determination With Non Cumulative Data, R. Lambert, A. Peeters
Radiation Use Efficiency Of Ryegrass: Determination With Non Cumulative Data, R. Lambert, A. Peeters
IGC Proceedings (1977-2023)
The growth of a crop is generally described as biomass accumulation per unit time. Monteith (1977) developed a model of growth where biomass accumulation is related to solar radiation intercepted by the crop. This model has been largely used for different crops. The conversion factor between radiation absorbed or intercepted by the crop and the biomass production is called “radiation use efficiency” or “dry matter radiation quotient”. Radiation use efficiency (RUE) is usually calculated as the regression coefficient of the linear relationship between crop biomass measured repeatedly during growth and cumulated intercepted or absorbed solar radiation. Demetriades-Shah et al. …