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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.

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A Single-Cell Gene Expression Atlas Of Human Follicular Aspirates: Identification Of Leukocyte Subpopulations And Their Paracrine Factors, Yohan Choi, Hayce Jeon, Mats Brännström, James W. Akin, Thomas E. Curry, Misung Jo Mar 2023

A Single-Cell Gene Expression Atlas Of Human Follicular Aspirates: Identification Of Leukocyte Subpopulations And Their Paracrine Factors, Yohan Choi, Hayce Jeon, Mats Brännström, James W. Akin, Thomas E. Curry, Misung Jo

UK CARES Faculty Publications

Leukocytes are in situ regulators critical for ovarian function. However, little is known about leukocyte subpopulations and their interaction with follicular cells in ovulatory follicles, especially in humans. Single-cell RNA sequencing (scRNA- seq) was performed using follicular aspirates obtained from four IVF patients and identified 13 cell groups: one granulosa cell group, one thecal cell group, 10 subsets of leukocytes, and one group of RBC/platelet. RNA velocity analyses on five granulosa cell populations predicted developmental dynamics denoting two projections of differentiation states. The cell type-specific transcriptomic profiling analyses revealed the presence of a diverse array of leukocyte-derived factors that can …

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Loss Of Peroxiredoxin Iv Protects Mice From Azoxymethane/Dextran Sulfate Sodium-Induced Colorectal Cancer Development, Pratik Thapa, Hong Jiang, Na Ding, Yanning Hao, Aziza Alshahrani, Eun Young Lee, Junichi Fujii, Qiou Wei Mar 2023

Loss Of Peroxiredoxin Iv Protects Mice From Azoxymethane/Dextran Sulfate Sodium-Induced Colorectal Cancer Development, Pratik Thapa, Hong Jiang, Na Ding, Yanning Hao, Aziza Alshahrani, Eun Young Lee, Junichi Fujii, Qiou Wei

Markey Cancer Center Faculty Publications

Peroxiredoxin IV (Prx4), a typical two-cysteine-containing member of the peroxidase family, functions as an antioxidant to maintain cellular redox homeostasis through the reduction of reactive oxygen species (ROS) via cycles of oxidation–reduction reactions. Under oxidative stress, all Prxs including Prx4 are inactivated as their catalytic cysteines undergo hyperoxidation, and hyperoxidized two-cysteine Prxs can be exclusively repaired and revitalized through the reduction cycle catalyzed by sulfiredoxin (Srx). Previously, we showed that Prx4 is a preferred substrate of Srx, and knockout of Srx in mice leads to resistance to azoxymethane/dextran sulfate sodium (AOM/DSS)-induced colon carcinogenesis. To further understand the significance of the …

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Exposure To Pcb126 During The Nursing Period Reversibly Impacts Early-Life Glucose Tolerance, Brittany Breon Rice, Keegan W. Sammons, Sara Y. Ngo Tenlep, Madeline T. Weltzer, Leryn J. Reynolds, Cetewayo S. Rashid, Hollie I. Swanson, Kevin J. Pearson Mar 2023

Exposure To Pcb126 During The Nursing Period Reversibly Impacts Early-Life Glucose Tolerance, Brittany Breon Rice, Keegan W. Sammons, Sara Y. Ngo Tenlep, Madeline T. Weltzer, Leryn J. Reynolds, Cetewayo S. Rashid, Hollie I. Swanson, Kevin J. Pearson

Markey Cancer Center Faculty Publications

Polychlorinated biphenyls (PCBs) are persistent environmental organic pollutants known to have detrimental health effects. Using a mouse model, we previously demonstrated that PCB126 exposure before and during pregnancy and throughout the perinatal period adversely affected offspring glucose tolerance and/or body composition profiles. The purpose of this study was to investigate the glucose tolerance and body composition of offspring born to dams exposed to PCB126 during the nursing period only. Female ICR mice were bred, and half of the dams were exposed to either vehicle (safflower oil) or 1 μmole PCB126 per kg of body weight via oral gavage on postnatal …

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Chronic Environmental Circadian Disruption Increases Atherosclerosis And Dyslipidemia In Female, But Not Male, Apolipoproteine-Deficient Mice, Jeffrey M. Chalfant, Deborah A. Howatt, Victoria B. Johnson, Lisa R. Tannock, Alan Daugherty, Julie S. Pendergast Mar 2023

Chronic Environmental Circadian Disruption Increases Atherosclerosis And Dyslipidemia In Female, But Not Male, Apolipoproteine-Deficient Mice, Jeffrey M. Chalfant, Deborah A. Howatt, Victoria B. Johnson, Lisa R. Tannock, Alan Daugherty, Julie S. Pendergast

Saha Cardiovascular Research Center Faculty Publications

Shift work chronically disrupts circadian rhythms and increases the risk of developing cardiovascular disease. However, the mechanisms linking shift work and cardiovascular disease are largely unknown. The goal of this study was to investigate the effects of chronically shifting the light-dark (LD) cycle, which models the disordered exposure to light that may occur during shift work, on atherosclerosis. Atherosclerosis is the progressive accumulation of lipid-filled lesions within the artery wall and is the leading cause of cardiovascular disease. We studied ApolipoproteinE-deficient (ApoE−/−) mice that are a well-established model of atherosclerosis. Male and female ApoE−/− mice were housed in control 12L:12D …

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Cervical Spinal Cord Injury Leads To Injury And Altered Metabolism In The Lungs, Emily E. Huffman, Brittany E. Dong, Harrison A. Clarke, Lyndsay E. A. Young, Matthew S. Gentry, Derek B. Allison, Ramon C. Sun, Christopher M. Waters, Warren J. Alilain Mar 2023

Cervical Spinal Cord Injury Leads To Injury And Altered Metabolism In The Lungs, Emily E. Huffman, Brittany E. Dong, Harrison A. Clarke, Lyndsay E. A. Young, Matthew S. Gentry, Derek B. Allison, Ramon C. Sun, Christopher M. Waters, Warren J. Alilain

Saha Cardiovascular Research Center Faculty Publications

High-cervical spinal cord injury often disrupts respiratory motor pathways and disables breathing in the affected population. Moreover, cervically injured individuals are at risk for developing acute lung injury, which predicts substantial mortality rates. While the correlation between acute lung injury and spinal cord injury has been found in the clinical setting, the field lacks an animal model to interrogate the fundamental biology of this relationship. To begin to address this gap in knowledge, we performed an experimental cervical spinal cord injury (N = 18) alongside sham injury (N = 3) and naïve animals (N = 15) to assess lung injury …

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Ferric Chloride-Induced Arterial Thrombosis And Sample Collection For 3d Electron Microscopy Analysis, Smita Joshi, Alexis N. Smith, Kanakanagavalli Shravani Prakhya, Hammodah Rawhi Hammodah Alfar, Joshua Lykins, Ming Zhang, Irina D. Pokrovskaya, Maria A. Aronova, Richard D. Leapman, Brian Storrie, Sidney W. Whiteheart Mar 2023

Ferric Chloride-Induced Arterial Thrombosis And Sample Collection For 3d Electron Microscopy Analysis, Smita Joshi, Alexis N. Smith, Kanakanagavalli Shravani Prakhya, Hammodah Rawhi Hammodah Alfar, Joshua Lykins, Ming Zhang, Irina D. Pokrovskaya, Maria A. Aronova, Richard D. Leapman, Brian Storrie, Sidney W. Whiteheart

Saha Cardiovascular Research Center Faculty Publications

Cardiovascular diseases are a leading cause of mortality and morbidity worldwide. Aberrant thrombosis is a common feature of systemic conditions like diabetes and obesity, and chronic inflammatory diseases like atherosclerosis, cancer, and autoimmune diseases. Upon vascular injury, usually the coagulation system, platelets, and endothelium act in an orchestrated manner to prevent bleeding by forming a clot at the site of the injury. Abnormalities in this process lead to either excessive bleeding or uncontrolled thrombosis/insufficient antithrombotic activity, which translates into vessel occlusion and its sequelae. The FeCl3-induced carotid injury model is a valuable tool in probing how thrombosis initiates and progresses …

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Chalcone Derivative Cx258 Suppresses Colorectal Cancer Via Inhibiting The Top2a/Wnt/Β-Catenin Signaling, Xi Chen, Xiaocheng Lv, Lijie Gao, Jiawei Liu, Wei Wang, Lichao Guo, Mykhaylo S. Frasinyuk, Wen Zhang, David S. Watt, Chunming Liu, Xifu Liu Mar 2023

Chalcone Derivative Cx258 Suppresses Colorectal Cancer Via Inhibiting The Top2a/Wnt/Β-Catenin Signaling, Xi Chen, Xiaocheng Lv, Lijie Gao, Jiawei Liu, Wei Wang, Lichao Guo, Mykhaylo S. Frasinyuk, Wen Zhang, David S. Watt, Chunming Liu, Xifu Liu

Markey Cancer Center Faculty Publications

The deregulation in the Wnt/β-catenin signaling pathway is associated with many human cancers, particularly colorectal cancer (CRC) and, therefore, represents a promising target for drug development. We have screened over 300 semisynthetic and natural compounds using a Wnt reporter assay and identified a family of novel chalcone derivatives (CXs) that inhibited Wnt signaling and CRC cell proliferation. Among them, we selected CX258 for further in vitro and in vivo study to investigate the molecular mechanisms. We found that CX258 significantly inhibited β-catenin expression and nuclear translocation, inducing cell cycle arrest at the G2/M phase in CRC cells. Additionally, CX258 reduced …

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Endogenous Glycoprotein Gpm6a Is Involved In Neurite Outgrowth In Rat Dorsal Root Ganglion Neurons, Gabriela I. Aparicio, Antonella León, Rocío Gutiérrez Fuster, Baylen Ravenscraft, Paula V. Monje, Camila Scorticati Mar 2023

Endogenous Glycoprotein Gpm6a Is Involved In Neurite Outgrowth In Rat Dorsal Root Ganglion Neurons, Gabriela I. Aparicio, Antonella León, Rocío Gutiérrez Fuster, Baylen Ravenscraft, Paula V. Monje, Camila Scorticati

Markey Cancer Center Faculty Publications

The peripheral nervous system (PNS) has a unique ability for self-repair. Dorsal root ganglion (DRG) neurons regulate the expression of different molecules, such as neurotrophins and their receptors, to promote axon regeneration after injury. However, the molecular players driving axonal regrowth need to be better defined. The membrane glycoprotein GPM6a has been described to contribute to neuronal development and structural plasticity in central-nervous-system neurons. Recent evidence indicates that GPM6a interacts with molecules from the PNS, although its role in DRG neurons remains unknown. Here, we characterized the expression of GPM6a in embryonic and adult DRGs by combining analysis of public …

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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.

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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 …

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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.

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Prediction Of Indigestible Ndf Content Of Grass And Legume Silages By Nirs, L. Nyholm, M. Rinne, M. Hellämäki, P. Huhtanen, J. Nousiainen Feb 2023

Prediction Of Indigestible Ndf Content Of Grass And Legume Silages By Nirs, L. Nyholm, M. Rinne, M. Hellämäki, P. Huhtanen, J. Nousiainen

IGC Proceedings (1977-2023)

The future feed evaluation systems based on mechanistic digestion models require reliable estimates of forage digestible and indigestible NDF content (DNDF and INDF). The objective of this study was to examine the potential of near infrared reflectance spectroscopy (NIRS) in predicting INDF content of grass and legume silages.

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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 (1977-2023)

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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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 (1977-2023)

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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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 (1977-2023)

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 (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) …

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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 (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. …

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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 (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.

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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 (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 …

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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 (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.

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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 …

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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 (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.

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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 (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.

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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 (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 …

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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 (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) …

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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 (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 …

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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 (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.

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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 (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).

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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 (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.

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