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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 (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.


Effect Of Nitrogen On The Radiation Use Efficiency For Modelling Grass Growth, R. Lambert, A. Peeters Feb 2023

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 Feb 2023

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 Feb 2023

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. …


Modelling The Digestibility Decrease Of Three Grass Species During Spring Growth According To The Age Of The Grass, The Thermal Age And The Yield, M. E. Salamanca, R. Lambert, M. Gomez, A. Peeters Feb 2023

Modelling The Digestibility Decrease Of Three Grass Species During Spring Growth According To The Age Of The Grass, The Thermal Age And The Yield, M. E. Salamanca, R. Lambert, M. Gomez, A. Peeters

IGC Proceedings (1977-2023)

The nutritive value of forage changes during growth. For the protein content, a general evolution curve was found with the yield increase (Salette & Lemaire, 1984). The digestibility of the organic matter decreases during growth as cellulose and lignin content increase. Regrowth age is the main factor, which explains the digestibility decrease (Demarquilly & Jarrige, 1981). The crop age can be expressed in number of growth days but also in thermal age (cumulated temperature). We compared the digestibility change of three grass species during spring growth for two years as a function of yield increase, thermal age or number of …


Pâtur’In: A User-Friendly Software Tool To Assist Dairy Cow Grazing Management, L. Delaby, J. L. Peyraud, P. Faverdin Feb 2023

Pâtur’In: A User-Friendly Software Tool To Assist Dairy Cow Grazing Management, L. Delaby, J. L. Peyraud, P. Faverdin

IGC Proceedings (1977-2023)

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 …


Enhancing Grasslands Education With Decision Support Tools, H. G. Daily, J. M. Scott, J. M. Reid Feb 2023

Enhancing Grasslands Education With Decision Support Tools, H. G. Daily, J. M. Scott, J. M. Reid

IGC Proceedings (1977-2023)

We have successfully used Decision Support Tools (DST) relevant to the management of grazing enterprises to enhance problem solving skills of undergraduates in Australia. Tools such as GrassGro™ (Moore et al., 1997) and GrazFeed™ (Freer et al., 1997) are accessed from a central server by authorised users at many widely dispersed Universities across Australia using remote access to thin-client technology via an Internet portal. This has been supplemented with training for lecturers. Experience in developing appropriate teaching and learning materials and the reliable delivery of simulation software to many clients has enhanced learning outcomes at tertiary level. We …


Using The Grassgro Decision Support Tool To Evaluate The Response In Grazing Systems To Pasture Legume Or A Grass Cultivar With Improved Nutritive Value, H. Dove, J. R. Donnelly Feb 2023

Using The Grassgro Decision Support Tool To Evaluate The Response In Grazing Systems To Pasture Legume Or A Grass Cultivar With Improved Nutritive Value, H. Dove, J. R. Donnelly

IGC Proceedings (1977-2023)

Decision support tools (DST) based on models of grazing systems allow the evaluation of changes in enterprise management on productivity and profitability. The Grassgro DST (Moore et al., 1997) uses historical weather data on a daily time step to simulate pasture growth and the resultant productivity of either grazing sheep or cattle. Different pasture species are represented within a parameter set that describes the response of pasture species to their environment. Manipulation of these parameters provides a means of evaluating, a priori, the likely responses of livestock production to ‘improved cultivars’. We report the results of simulations conducted …


Field Testing Of A Turnip Growing Protocol On New Zealand Dairy Farms, J. P. J. Eerens, P. M. S. Lane Feb 2023

Field Testing Of A Turnip Growing Protocol On New Zealand Dairy Farms, J. P. J. Eerens, P. M. S. Lane

IGC Proceedings (1977-2023)

Summer droughts are a regular occurrence in central North Island districts of New Zealand, which causes pastures to wilt, lose their nutritive value and stop growing. The resulting summer feed gap depresses farm productivity (Clark et al., 1996). Turnips optimally sown mid-late October (more often sown in November or even December) are grown to fill this feed gap. Recorded average yields of 7.4 t dry matter (DM)/ha are below the economic breakeven point of 8-10 t DM/ha (Clark et al., 1996). A turnip growing protocol was developed from published data (Eerens & Lane 2004) and tested on commercial …


Use Of Alkanes To Estimate Dry Matter Intake Of Beef Steers Grazing High Quality Pastures, G. Scaglia, H. T. Boland, I. Lopez-Guerrero, R. K. Shanklin, J. P. Fontenot Feb 2023

Use Of Alkanes To Estimate Dry Matter Intake Of Beef Steers Grazing High Quality Pastures, G. Scaglia, H. T. Boland, I. Lopez-Guerrero, R. K. Shanklin, J. P. Fontenot

IGC Proceedings (1977-2023)

Pastures remain the most important source of nutrients for ruminant livestock and nutrition is critical to optimize animal production. The daily quantity of dry matter that is consumed by an animal is a critical measurement to make nutritional inferences about feed and subsequent animal response. Researchers are facing the dilemma that, while estimates of individual animal performance are readily obtained, it is still difficult to estimate the herbage intake of individual animals. The objectives of this experiment were to estimate forage intake in beef steers grazing tall fescue (Festuca arundinacea Schreb.) and alfalfa (Medicago sativa)/tall fescue pastures …


Objectives And Benefits Of Molecular Breeding In Forage Species, T. Lübberstedt Feb 2023

Objectives And Benefits Of Molecular Breeding In Forage Species, T. Lübberstedt

IGC Proceedings (1977-2023)

  1. The amount of resources and information provided by forage crop genomic programs has dramatically increased during the past few years.
  2. Trait-based forward genetic procedures such as mapping and expression profiling have successfully provided new candidate genes or genome regions affecting forage quality. Respective information can easily be transferred across related forage species.
  3. Since several genes in major biochemical pathways related to forage traits have been isolated, gene-based reverse genetic approaches (transformation, association studies) are promising.
  4. Most genetic experiments are conducted under simplified "artificial" conditions such as on single-spaced plants. Therefore, transferability of respective genetic information to breeding practice needs to …


Exploring The Existence Of Transformational Education In The Nys Social Studies Curriculum And Civic Readiness Initiative, Gregory Vincent Massara Feb 2023

Exploring The Existence Of Transformational Education In The Nys Social Studies Curriculum And Civic Readiness Initiative, Gregory Vincent Massara

Educational Policy & Leadership Other Graduate Student Scholarship

The enormity and perniciousness of economic, social, and environmental sustainability challenges are evident through several avenues. The Intergovernmental Panel on Climate Change is issuing increasingly dire warnings for the future of life on Earth. Threats to social cohesion, evidenced particularly in the institutionalization of injustices and the current fragility of democracy in the United States, highlight the need for increased social cohesion. Furthermore, rising economic inequality, inequities based on gender and race, and the increasing cost of damages caused by climate events highlight economic challenges. In 2015, the United Nations put forth an agenda to address economic, social, and environmental …


Update On Options For Managing Thin Alfalfa Stands, Jimmy C. Henning Feb 2023

Update On Options For Managing Thin Alfalfa Stands, Jimmy C. Henning

Kentucky Alfalfa and Stored Forage Conference

Alfalfa is the highest yielding, highest quality hay crop grown in Kentucky. Well cured alfalfa and alfalfa‐grass hay is in high demand for dairy and in particular, horse owners. Alfalfa stands in Kentucky remain productive from four to as long as 8 years or more depending on several factors. Long stand life is favored by:

1. Using an improved variety with high resistance to the major diseases of Kentucky and that is proven to be high yielding in relevant trials such as conducted at the University of Kentucky.

2. Deep, well drained soils,

3. Soils that have been limed to …


Attacking The Yield Plateau: Assessing The Nutrient Status Of Kentucky Alfalfa Stands, W. R. Fleming, C. D. Teutsch, E. L. Ritchey, J. H. Grove Feb 2023

Attacking The Yield Plateau: Assessing The Nutrient Status Of Kentucky Alfalfa Stands, W. R. Fleming, C. D. Teutsch, E. L. Ritchey, J. H. Grove

Kentucky Alfalfa and Stored Forage Conference

Soil and tissue analyses indicated that alfalfa yields may be limited in some cases by soil fertility. Soil pH was below the optimal range in more than 40% of the fields sampled. This may result in decreased nitrogen fixation and nutrient availability. Potassium was reported low in approximately one‐quarter of the sampled stands according to tissue analysis. This was not unexpected since hay production removes large quantities of potash. Sulfur and magnesium were reported low in 13 and 23 percent of stands, respectively. More work is needed to better understand if these two 2023 Kentucky Alfalfa and Stored Forage Conference …


Hay Production In The Deep South: Bermudagrass And Alfalfa A Perfect Combination, Jennifer J. Tucker Feb 2023

Hay Production In The Deep South: Bermudagrass And Alfalfa A Perfect Combination, Jennifer J. Tucker

Kentucky Alfalfa and Stored Forage Conference

No abstract provided.


National Producer And Consumer Survey: Increasing Alfalfa Hay Sales To Horse Owners, Krista Lea, Bob Coleman, Laurie Lawrence, Jen Zimmerman, Ray Smith Feb 2023

National Producer And Consumer Survey: Increasing Alfalfa Hay Sales To Horse Owners, Krista Lea, Bob Coleman, Laurie Lawrence, Jen Zimmerman, Ray Smith

Kentucky Alfalfa and Stored Forage Conference

Horse owners were surveyed regarding their hay feeding choices. Unique factors of this market are discussed.


Hygienic Value And Mycotoxins Level Of Grass Silage In Bales For Horses, A. Potkański, J. Grajewski, K. Raczkowska-Werwińska, B. Miklaszewska, A. Gubała, M. Selwet, M. Szumacher-Strabel Feb 2023

Hygienic Value And Mycotoxins Level Of Grass Silage In Bales For Horses, A. Potkański, J. Grajewski, K. Raczkowska-Werwińska, B. Miklaszewska, A. Gubała, M. Selwet, M. Szumacher-Strabel

IGC Proceedings (1977-2023)

Mycotoxins are secondary metabolites of moulds which have adverse effects on humans, animals, and crops and result in illnesses and economic losses. The toxins may occur in storage under conditions favourable for the growth of the toxin-producing fungus or fungi. The highest forage concentration of toxins was found in horizontal storage methods such as bunker silos and feed piles, which were left open to oxygen. In any fermentation storage system, temperature and the presence of moisture is sufficient for toxin production. In a plastic covered storage system, oxygen penetration is slowed but not eliminated. The longer silage is stored, the …


Appearance Of Two Distinct Clusters Of Glucose Dysregulation In Chronic Intractable Migraine, Roshni Jogin, Kaitlyn Mcfarland, Aparna Naik, Tanner Williford, Matthew Conway, Amar Paul, John A. Kriak, David W. Sant, Kyle B. Bills Feb 2023

Appearance Of Two Distinct Clusters Of Glucose Dysregulation In Chronic Intractable Migraine, Roshni Jogin, Kaitlyn Mcfarland, Aparna Naik, Tanner Williford, Matthew Conway, Amar Paul, John A. Kriak, David W. Sant, Kyle B. Bills

Annual Research Symposium

No abstract provided.


Association Between Vitamin D And Cardiovascular Disease: Findings From A National Study, Monica Ocampo, Amir Mohajeri, Man Hung Feb 2023

Association Between Vitamin D And Cardiovascular Disease: Findings From A National Study, Monica Ocampo, Amir Mohajeri, Man Hung

Annual Research Symposium

ABSTRACT

Introduction

Many studies have investigated the association between vitamin D and cardiovascular disease (CVD), but literature has shown various results. The aim of this study was to investigate the role of vitamin D in CVD.

Methods

Data source

The data were obtained from the 2015-2018 National Health and Nutrition Examination Survey database and included adults aged 20 years and older with a history of CVD. Descriptive statistics for participants’ demographics, vitamin D levels, CVD status, and risk factors were reported. Chi-square tests and t-tests were performed to examine differences in participant characteristics among those who had CVD and did …


Aerobic Stability And Nutritive Value Of Low Dry Matter Maize Silage Treated With A Formic Acid-Based Preservative, I. Filya, E. Sucu, A. Karabulut Feb 2023

Aerobic Stability And Nutritive Value Of Low Dry Matter Maize Silage Treated With A Formic Acid-Based Preservative, I. Filya, E. Sucu, A. Karabulut

IGC Proceedings (1977-2023)

Aerobic stability is one of the major problems of the ensiling process, especially in warm climates. Ashbell et al. (2002) have shown that at 30°C, the development of aerobic yeast and moulds in silages is most intensive. In Turkey all silages are susceptible to air penetration during storage and unloading with a large proportion of the silage spoiled and in extreme cases all the silage is spoiled. The purpose of the present work was to study the effects of formic acid-based preservative (FAB; Kemisile® 2000, Kemira Oyj-Industrial Chemicals, Finland) on the aerobic stability and nutritive value of maize silage.


The Effects Of The Growth Stage And Inoculant On Fermentation And Aerobic Stability Of Whole-Plant Grain Sorghum Silage, E. Tabacco, G. Borreani Feb 2023

The Effects Of The Growth Stage And Inoculant On Fermentation And Aerobic Stability Of Whole-Plant Grain Sorghum Silage, E. Tabacco, G. Borreani

IGC Proceedings (1977-2023)

Grain sorghum (Sorghum bicolor) is well adapted to environments with limited rainfall and low soil fertility. Today, on dry land, improved grain sorghum hybrids may be a valid alternative to maize silage and they may give DM yields and digestible energy that are comparable to maize, but at lower production costs (Legarto, 2000). Harvesting crops for silage at an early stage of maturity (low DM content) may result in silage with a higher acid content and low nutritional quality, while harvesting crops at a later stage of maturity may make the forage more difficult to chop and pack. …