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Protection Of Agrobiodiversity: Model Calculations In Rhineland-Palatia: Costs And Implications For Farmers, H. Bergmann Mar 2023

Protection Of Agrobiodiversity: Model Calculations In Rhineland-Palatia: Costs And Implications For Farmers, H. Bergmann

IGC Proceedings (1977-2023)

Biological conservation and production use the same areas of land in less favoured areas. Grassland in these areas makes an important contribution to the protection of agro-biodiversity. However, under existing market conditions and production needs, the use of low yielding grasslands is not economically efficient. The objective of this study was to analyze the economic consequences of different mowing strategies in a small region in Rhineland-Palatia (Germany) that served the protection of two butterfly species.


Managing Resources By Grazing In Grasslands Dominated By Dominant Shrub Species, D. Magda, Cyril Agreil, Michel Meuret, E. Chambon-Dubreuil, P. -L. Osty Mar 2023

Managing Resources By Grazing In Grasslands Dominated By Dominant Shrub Species, D. Magda, Cyril Agreil, Michel Meuret, E. Chambon-Dubreuil, P. -L. Osty

IGC Proceedings (1977-2023)

The European natural grasslands are attracting new attention because of their environmental value as habitats for threatened fauna and flora species and their contribution to the diversity of landscapes. Those responsible for the implementation of the European agri-environmental policy are hence encouraging livestock farmers to adopt grazing practices that contribute to the conservation of grassland biodiversity especially by limiting encroachment by dominant shrubs. However, current scientific knowledge and technical information are often insufficient to connect flock feeding and the impact of grazing on shrub dynamics and livestock farmers are not very enthusiastic about restoring or conserving “plant mosaics” including shrubs …


Effect Of Urea-Treated Pennisetum Pedicellatum And Supplementation Of Concentrates With Urea On Milk Production Of “Mossi” Ewes, V. M. C. Bougouma-Yameogo, A. J. Nianogo Mar 2023

Effect Of Urea-Treated Pennisetum Pedicellatum And Supplementation Of Concentrates With Urea On Milk Production Of “Mossi” Ewes, V. M. C. Bougouma-Yameogo, A. J. Nianogo

IGC Proceedings (1977-2023)

The “Mossi” sheep is a near parent of “Djallonke” sheep that live in sudano-sahelian area of Burkina Faso. However, there are few available results on dairy production from this breed. The treatment of straw with urea is a technique used in several developing countries to improve the nutritional value of gramineous forages (Sourabié et al., 1995). The aim of this study was to test the influence on the performance of “Mossi” ewes and on milk composition of treatment of Pennisetum pedicellatum (Pp) with urea in comparison with addition of urea to the concentrate feed.


Using The N-Alkane Technique To Estimate The Herbage Intake And Diet Composition Of Cattle Grazing A Miscanthus Sinensis Grassland, Y. Zhang, Y. Togamura, K. Otsuki Mar 2023

Using The N-Alkane Technique To Estimate The Herbage Intake And Diet Composition Of Cattle Grazing A Miscanthus Sinensis Grassland, Y. Zhang, Y. Togamura, K. Otsuki

IGC Proceedings (1977-2023)

Plant wax alkanes are now widely used as marker substances (Dove & Mayes 1991) for the estimation of forage intake and diet composition of grazing herbivores. The objective of this study was to evaluate this method with cattle grazing a M. sinensis grassland in Japan.


Selecting Grassland Species For Saline Environments, M. E. Rogers, A. D. Craig, T. D. Colmer, R. Munns, S. J. Hughes, P. M. Evans, P. G. H. Nichols, R. Snowball, D. Henry, J. Deretic, B. Dear, M. Ewing Mar 2023

Selecting Grassland Species For Saline Environments, M. E. Rogers, A. D. Craig, T. D. Colmer, R. Munns, S. J. Hughes, P. M. Evans, P. G. H. Nichols, R. Snowball, D. Henry, J. Deretic, B. Dear, M. Ewing

IGC Proceedings (1977-2023)

In Australia, around 5.7 million hectares of agricultural land are currently affected by dryland salinity or at risk from shallow water tables and this figure is expected to increase over the next 50 years (LWRA, 2001). Most improved grassland species cannot tolerate the combined effects of salt and waterlogging and, therefore, the productivity of sown grasslands in salt-affected areas is low. However, there is potential to overcome the lack of suitably adapted fodder species by introducing new, salt and waterlogging-tolerant species and by diversifying the gene pool of proven species. Potential species include exotic, naturalised and native Australian grass, legumes, …


Effects Of The Stage Of Growth And Inoculation On Proteolysis In Field Pea Silage, L. Cavallarin, G. Borreani, S. Antoniazzi, E. Tabacco Mar 2023

Effects Of The Stage Of Growth And Inoculation On Proteolysis In Field Pea Silage, L. Cavallarin, G. Borreani, S. Antoniazzi, E. Tabacco

IGC Proceedings (1977-2023)

Ensiling legumes is a good way of providing home-grown protein in dairy farms but severe protein degradation can occur when conserving legumes. Peas (Pisum sativum L.) are legumes with a high crude protein and starch content, that provide a high forage yield in a short growing period. Very little information is available on the protein value of field pea silage. The aim of the study was to investigate the effect of stage of maturity and inoculant application on proteolysis in field pea silage in the Po Valley, NW Italy.


Grass Silage: Factors Affecting Efficiency Of N Utilisation In Milk Production, P. Huhtanen, K. J. Shingfield Mar 2023

Grass Silage: Factors Affecting Efficiency Of N Utilisation In Milk Production, P. Huhtanen, K. J. Shingfield

IGC Proceedings (1977-2023)

Key points

  1. Low efficiency of N utilisation for milk production in cows fed grass silage-based diets is mainly due to excessive N losses in the rumen.
  2. The type and extent of in silo fermentation can alter the balance of absorbed nutrients.
  3. There is very little experimental evidence that the capture of N in the rumen can be improved by a better synchrony between energy and N release in the rumen. Nitrogen losses in the rumen can be reduced by decreasing the ratio between rumen degradable N and fermentable energy.
  4. Rapeseed meal has increased milk protein output more than isonitrogenous soybean …


Decision Support For Grassland Systems In Developing Countries, P. K. Thornton Mar 2023

Decision Support For Grassland Systems In Developing Countries, P. K. Thornton

IGC Proceedings (1977-2023)

Key points

1. Information flows in complex systems are often themselves highly complex, and decision support approaches based on linear input-output processes may have only limited impact.

2. How decisions are made, and how they can be appropriately supported, is often incompletely understood, in part because of inadequate understanding of the objectives and attitudes of all the decision makers involved.

3. Much of the developing world faces daunting problems in the coming 30 years, and appropriate information could play a critical role in dealing with these.

4. System complexity, household variability, and institutional intricacies have to be embraced rather than …


Effect On Sward Botanical Composition Of Mixed And Sequential Grazing By Cattle And Sheep Of Upland Permanent Pasture In The Uk, J. E. Vale, M. D. Fraser, J. G. Evans Mar 2023

Effect On Sward Botanical Composition Of Mixed And Sequential Grazing By Cattle And Sheep Of Upland Permanent Pasture In The Uk, J. E. Vale, M. D. Fraser, J. G. Evans

IGC Proceedings (1977-2023)

Previous work has shown benefits of sequential grazing by cattle and sheep, with superior liveweight gains being recorded for lambs grazing swards previously grazed by cattle. A preliminary study of the effects of mixed sheep and cattle grazing also suggested that more extensively grazed swards offer scope for complementary grazing between sheep and cattle. The aim of this experiment was to directly compare these two approaches of integrating the grazing of cattle and sheep.


Effects Of Breed And Stage Of Growing Season On The Metabolic Profile Of Sheep Grazing Moorland, V. J. Theobald, M. D. Fraser, J. M. Moorby Mar 2023

Effects Of Breed And Stage Of Growing Season On The Metabolic Profile Of Sheep Grazing Moorland, V. J. Theobald, M. D. Fraser, J. M. Moorby

IGC Proceedings (1977-2023)

Previous studies have shown that the diet of sheep grazing heather moorland is affected by season (Grant et al., 1987) and the proportion of Calluna vulgaris cover (Osoro et al., 2000). In order to investigate the impact of these factors on the associated nutrient supply of animals grazing heathland, blood samples were taken to monitor the metabolic status of different breeds of sheep at different stages of the growing season when grazing sites with different proportions of heather cover.


Nutritional Value Of Pasture Forage For Sheep In Krkonoše National Park, P. Homolka Mar 2023

Nutritional Value Of Pasture Forage For Sheep In Krkonoše National Park, P. Homolka

IGC Proceedings (1977-2023)

This study describes the nutritional value of pastures in extreme mountain conditions in Krkonoše Mountains National Park. The Park performs important ecological and environmental functions. Extensive sheep grazing serves in the preservation of rare, protected and endangered species of plants (including endemics) and in the restoration of the biodiversity of meadows. The objective of this experiment was to estimate the production of plant biomass in these pastures and its digestibility by sheep.


Intensifying A Crop–Fallow System: Impacts On Soil Properties, Crop Yields, And Economics, S. J. Ruis, S. Stepanovic, Humberto Blanco-Canqui Mar 2023

Intensifying A Crop–Fallow System: Impacts On Soil Properties, Crop Yields, And Economics, S. J. Ruis, S. Stepanovic, Humberto Blanco-Canqui

Department of Agronomy and Horticulture: Faculty Publications

Intensifying crop–fallow systems could address increased weed control costs, increased land or rental costs, reduced crop diversity, and degraded soil properties in water-limited environments. One strategy to intensify such systems could be the insertion of a short-season crop during fallow. But, how this strategy affects soils, crop production, and farm economics needs further research. Thus, we studied the impacts of replacing fallow in a winter wheat (Triticum aestivum L)–corn (Zea mays L.)–fallow system with a short-season spring crop [field pea (Pisum sativum L.)] on crop yields and economics from 2015 to 2019 and 5-yr cumulative effects on …


Evaluating Metabolic And Genomic Data For Predicting Grain Traits Under High Night Temperature Stress In Rice, Ye Bi, Rafael Massahiro Yassue, Puneet Paul, Balpreet Kaur Dhatt, Jaspreet Sandhu, Phuc Thi Do, Harkamal Walia, Toshihiro Obata, Gota Morota Feb 2023

Evaluating Metabolic And Genomic Data For Predicting Grain Traits Under High Night Temperature Stress In Rice, Ye Bi, Rafael Massahiro Yassue, Puneet Paul, Balpreet Kaur Dhatt, Jaspreet Sandhu, Phuc Thi Do, Harkamal Walia, Toshihiro Obata, Gota Morota

Department of Agronomy and Horticulture: Faculty Publications

The asymmetric increase in average nighttime temperatures relative to increase in average daytime temperatures due to climate change is decreasing grain yield and quality in rice. Therefore, a better genome-level understanding of the impact of higher night temperature stress on the weight of individual grains is essential for future development of more resilient rice. We investigated the utility of metabolites obtained from grains to classify high night temperature (HNT) conditions of genotypes, and metabolites and single-nucleotide polymorphisms (SNPs) to predict grain length, width, and perimeter phenotypes using a rice diversity panel. We found that the metabolic profiles of rice genotypes …


Ruminal Proteolysis In Forages With Distinct Endopeptidases Activities, G. Pichard, C. Tapia, R. Larrain Feb 2023

Ruminal Proteolysis In Forages With Distinct Endopeptidases Activities, G. Pichard, C. Tapia, R. Larrain

IGC Proceedings (1977-2023)

Improving livestock efficiency in utilisation of nitrogen resources continues to be a major environmental and economic objective. Zhu et al. (1999) have shown that plant endopeptidases are activated as a response to cutting stress. Previous work in our laboratory explored over 300 entries of forage genotypes and found a broad diversity in enzymatic activity by means of hydrolysis in gelatine and direct autolysis assays in forage tissues. The objective of this work was to assess if the species previously identified as having high or low endopeptidase activity, would behave consistently when exposed to ruminal microbial proteolysis.


Effects Of Particle Size In Forage Samples For Protein Breakdown Studies, G. Pichard, C. Tapia Feb 2023

Effects Of Particle Size In Forage Samples For Protein Breakdown Studies, G. Pichard, C. Tapia

IGC Proceedings (1977-2023)

Coupling ruminal processes of hydrolysis and synthesis continues to be a research issue where more progress is needed. This requires the development of good protein assessment methods, particularly when representing the breakdown processes that occur in fresh pastures eaten by herbivores. Laboratory analyses need to deal with small and homogeneous samples, but the mechanical reduction of particle size may not reflect the actual digestion kinetics occurring when the original fresh forage is consumed. Such physical traits may alter the release of non-structural compounds and the penetration of microbial enzymes (Boudon et al., 2002). The objective of this work was …


A New System For The Evaluation Of The Fermentation Quality Of Silages, K. Weiß, E. Kaiser Feb 2023

A New System For The Evaluation Of The Fermentation Quality Of Silages, K. Weiß, E. Kaiser

IGC Proceedings (1977-2023)

Depending on the content of nitrate in green forage, the pattern of fermentation products in silages differ significantly (Weiß & Kaiser, 2001). The systems, which are now common in practice for evaluating the quality of silage fermentation, characterise fermentation quality incorrectly because the evaluation is influenced by the chemical composition of green forage. The aim of this work was to derive an evaluation system for fermentation quality, which is independent from the chemical composition of green forage.


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 (1977-2023)

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.


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 (1977-2023)

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.


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 (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 Feb 2023

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. …


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 (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 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 (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 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 (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.


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 (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 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 (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).


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 (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 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 (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 Feb 2023

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.


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 (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 Feb 2023

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.