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First Insight On The Genesis Of Iron Oxide-Hydroxide Biospeleothems In Rancho Chico Lava Tube, Mexico, Rafael López-Martínez, Elizabeth Solleiro-Rebolledo, Rocio Alcántara-Hernández, Teresa Pi Puig, Sergey Sedov, Daisy Valera Fernández, M. Nayeli Luis-Vargas, Yasmany Lima Vera, Jesús Solé, Ramon Espinasa-Pereña Jun 2025

First Insight On The Genesis Of Iron Oxide-Hydroxide Biospeleothems In Rancho Chico Lava Tube, Mexico, Rafael López-Martínez, Elizabeth Solleiro-Rebolledo, Rocio Alcántara-Hernández, Teresa Pi Puig, Sergey Sedov, Daisy Valera Fernández, M. Nayeli Luis-Vargas, Yasmany Lima Vera, Jesús Solé, Ramon Espinasa-Pereña

International Journal of Speleology

Iron is a common element in lava tube systems, typically observed as thin crusts or inferred from the reddish coloration of secondary mineral deposits. In this study, we describe iron oxide-hydroxide biospeleothems discovered in the Rancho Chico Lava Tube, located within the Xalapa Monogenetic Volcanic Field in Mexico. We adopt an integrative approach combining petrography, soil micromorphology, scanning electron microscopy, mineralogy, and 16S rRNA gene metabarcoding. DNA sequencing reveals the presence of microorganisms such as Acidithiobacillus, Gallionella, and members of the Leptospirillaceae family, which may be involved in the oxidation of Fe²⁺ within the lava tube. The source …


Hydrochemical Assessment And Geospatial Analysis Of Borehole Water Quality In Effurun, Delta State, Nigeria, Ojo Odunayo Tope, Ike Joy Chiaka, Austin Emeka Okoli, Namdie Joseph Inyang Jun 2025

Hydrochemical Assessment And Geospatial Analysis Of Borehole Water Quality In Effurun, Delta State, Nigeria, Ojo Odunayo Tope, Ike Joy Chiaka, Austin Emeka Okoli, Namdie Joseph Inyang

Al-Bahir

Borehole water is a primary drinking water source in Effurun, Delta State, Nigeria, making its quality a critical public health concern. Contaminants such as major ions and trace metals can affect water safety, necessitating comprehensive assessment. This study evaluates the hydrochemical characteristics of borehole water, identifies contamination sources, and assesses compliance with World Health Organization (WHO) and Nigerian Standard for Drinking Water Quality (NSDWQ) guidelines. The study aims to determine the spatial distribution of major ions and trace metals in borehole water, assess water quality variations, and identify contamination patterns due to natural and anthropogenic influences. Water samples were collected …


Harboring Change: Legacy Contamination, Plant-Metal Dynamics, And The Fate Of A Boston Marsh, Emma Brooks Jun 2025

Harboring Change: Legacy Contamination, Plant-Metal Dynamics, And The Fate Of A Boston Marsh, Emma Brooks

Graduate Masters Theses

Coastal wetlands within the Boston Harbor watershed provide numerous ecosystem services and community benefits but are challenged by anthropogenic influence including a legacy of pollution and increasing mean sea level. In this thesis, I will consider the historic and present sources of contamination in Boston Harbor, the role an individual salt marsh species (Salicornia depressa) plays in the movement of heavy metals, and how projected sea level rise and urbanization may affect future marsh viability. These complex issues are explored through a case study of Pattens Cove, a 9.6-acre parcel of state-managed land in Dorchester, MA home to …


Analyzing Human - Nonhuman Primate Conflict Mitigation Techniques In Mto Wa Mbu, Northern Tanzania, Lil Adams Jun 2025

Analyzing Human - Nonhuman Primate Conflict Mitigation Techniques In Mto Wa Mbu, Northern Tanzania, Lil Adams

Undergraduate Theses, Capstones, and Recitals

Human-wildlife conflict is a widespread challenge faced by those living in regular contact with wildlife that can have profound impacts on livelihood outcomes for humans, wildlife, and their shared environment (Barua et al., 2013; Blackie, 2023). Human – non-human primate conflict is particularly crucial due to primates’ high capacity to live among human populations (Chapman & Chapman, 1990; Alberts & Altmann, 2006; Reader et al., 2011; Sinha & Vijayakrishnan, 2017), and is currently on the rise due to increasing contact between human and non-human primates (Hockings, 2016; Uddin et al., 2020). To characterize and analyze techniques currently being used to …


Tracking The Kinetics Cellular Glycolysis And Glutaminolysis Pathways Using Vibrational Spectroscopy, Combined With Multivariate Statistical And Machine Learning Approaches For Data Mining, Zohreh Mirveis, Nithin Patil, Hugh Byrne Jun 2025

Tracking The Kinetics Cellular Glycolysis And Glutaminolysis Pathways Using Vibrational Spectroscopy, Combined With Multivariate Statistical And Machine Learning Approaches For Data Mining, Zohreh Mirveis, Nithin Patil, Hugh Byrne

SAML-25 Workshop on Statistical and Machine Learning

Understanding dynamic metabolic processes within living cells is crucial for gaining insights into cellular function and disease mechanisms. The kinetics of glycolysis and glutaminolysis pathways play significant roles, as alterations in their activity have been linked to various disorders, including cancer and mental health conditions such as bipolar disorder. These pathways therefore hold potential as biomarkers for disease diagnosis and therapy. However, real-time monitoring of their kinetics remains challenging due to the lack of suitable non-invasive techniques. Current gold-standard fluxomics approaches, such as mass spectrometry, are destructive to cells and thus unsuitable for time-resolved studies. In this study, we evaluate …


Motionteller: Multi-Modal Integration Of Wearable Time-Series With Llms For Health And Behavioral Understanding, Aiwei Zhang, Arvind Pillai, Andrew Campbell, Nicholas C. Jacobson Jun 2025

Motionteller: Multi-Modal Integration Of Wearable Time-Series With Llms For Health And Behavioral Understanding, Aiwei Zhang, Arvind Pillai, Andrew Campbell, Nicholas C. Jacobson

Computer Science Senior Theses

As wearable sensing becomes increasingly pervasive, a key challenge remains: how can we generate natural language summaries from raw physiological signals such as actigraphy - minute-level movement data collected via accelerometers? In this work, we introduce MotionTeller, a generative framework that natively integrates minute-level wearable activity data with large language models (LLMs). MotionTeller combines a pretrained actigraphy encoder with a lightweight projection module that maps behavioral embeddings into the token space of a frozen decoder-only LLM, enabling free-text, autoregressive generation of daily behavioral summaries.

We construct a novel dataset of 54,383 ⟨actigraphy, text⟩ pairs derived from real-world NHANES recordings, and …


Molecular Insights Into The Role Of Estrogen Receptor Beta In Ecdysterone Mediated Anabolic Activity, Syeda Sumayya Tariq, Madiha Sardar, Muhammad Shafiq, Hendrick Heinz, Mohammad Nur-E-Alam, Aftab Ahmad, Zaheer Ul-Haq Jun 2025

Molecular Insights Into The Role Of Estrogen Receptor Beta In Ecdysterone Mediated Anabolic Activity, Syeda Sumayya Tariq, Madiha Sardar, Muhammad Shafiq, Hendrick Heinz, Mohammad Nur-E-Alam, Aftab Ahmad, Zaheer Ul-Haq

Pharmacy Faculty Articles and Research

Ecdysterone, often dubbed a “natural steroid,” has garnered significant attention among athletes for its reputed growth-promoting and anabolic properties. Unlike synthetic anabolic steroids, which are classified as controlled substances, ecdysteroids remain largely unregulated in many countries and are widely marketed as dietary supplements. Notably, ecdysterone has been included in the World Anti-Doping Agency (WADA) monitoring program, highlighting its potential impact on athletic performance and raising questions about its regulation. Emerging evidence indicates that, unlike traditional anabolic steroids that act primarily via the Androgen Receptor (AR), ecdysterone’s anabolic effects may be mediated through Estrogen Receptors (ERs), particularly Estrogen Receptor beta (ERβ). …


"Maine Office Of Behavioral Health’S Section 17 Self-Direction Pilot Program: Evaluation Report", Rachel M. Gallo Mph, Sarah Goan, Emma Schwartz, Aaron Rose Jun 2025

"Maine Office Of Behavioral Health’S Section 17 Self-Direction Pilot Program: Evaluation Report", Rachel M. Gallo Mph, Sarah Goan, Emma Schwartz, Aaron Rose

Publications

Maine’s Office of Behavioral Health conducted a nine-month pilot of Self-Directed Care to support adults with serious mental illness in Cumberland, Hancock, and Washington Counties. The program allowed eligible participants receiving MaineCare Section 17 services to manage a personal budget, guided by trained Support Brokers from Alpha One, to purchase goods and services that would advance their recovery goals. The pilot aimed to increase participant choice, autonomy, and flexibility in managing their mental health needs. Support Brokers worked closely with participants and Case Managers to develop and approve individualized purchase plans, monitor expenditures, and ensure alignment with treatment objectives. A …


Poa Annua Ecology, Biology, And Integrated Weed Management Practices In Turfgrass, David Ervin Jun 2025

Poa Annua Ecology, Biology, And Integrated Weed Management Practices In Turfgrass, David Ervin

Environmental Science and Management Faculty Publications and Presentations

Poa annua L. is one of the most widespread and troublesome weeds of turfgrass. It persists as both an annual and perennial and is adaptable to almost any static maintenance regime, including adaptation to mowing heights and evolution of herbicide resistance. This management guide is intended to provide stakeholders with a summary of new and existing knowledge on integrated Poa annua management. Here we review the basic biology and ecology, as well as practical integrated weed management (IWM) strategies developed for its control.


The Influence Of Black Soldier Fly Residue On Watermelon Growth And The Properties Of A Coarse-Textured Ultisol, Benedict Onyebuchi Unagwu, Chidiebere Fransica Odu, Chinedu Felix Amuji, Michael Onyedika Eze, Nancy Ekene Ebido, Chidike Ude Abara, Chioma Rosita Igboka, Uchechukwu Paschal Chukwudi Jun 2025

The Influence Of Black Soldier Fly Residue On Watermelon Growth And The Properties Of A Coarse-Textured Ultisol, Benedict Onyebuchi Unagwu, Chidiebere Fransica Odu, Chinedu Felix Amuji, Michael Onyedika Eze, Nancy Ekene Ebido, Chidike Ude Abara, Chioma Rosita Igboka, Uchechukwu Paschal Chukwudi

Chemistry Faculty Research & Creative Works

Improving the fertility status of nutrient-depleted soils is critical to achieving food security. The negative effects of chemical fertilizers on soils necessitate the global quest for eco-friendly, effective, and sustainable alternatives. This work assessed the effect of black soldier fly (BSF) residue application on soil properties and watermelon growth. The study was set up in a completely randomized design with six replications. The treatments were BSF1 (BSF applied at 10 t ha−1), BSF2 (20 t ha−1), BSF3 (30 t ha−1), and control. The plant data collected in this study were vine length, leaf width, …


Raising The Roof For All: Integrating Companion Planting Ecology, Policy And Community In Portland's Green Roof Future, Zoe Edelman Jun 2025

Raising The Roof For All: Integrating Companion Planting Ecology, Policy And Community In Portland's Green Roof Future, Zoe Edelman

University Honors Theses

Green roofs, or ecoroofs, provide environmental and social benefits in urban areas. Ecoroofs manage stormwater by absorbing rainfall, reducing rooftop temperatures, supporting pollinators, and offering green space in densely developed cities. Portland, Oregon has adopted progressive policies that encourage green roof installation through incentives and building requirements. However, many ecoroofs in the city are underperforming due to poor maintenance, low public awareness, and limited access to rooftop spaces. This thesis explores whether companion planting can improve the ecological performance and long- term viability of extensive green roofs. A rooftop experiment at Portland State University tested the growth of radishes, with …


Hd-Epic: A Highly-Detailed Egocentric Video Dataset, Toby Perrett, Ahmad Darkhalil, Saptarshi Sinha, Omar Emara, Sam Pollard, Kranti Kumar Parida, Kaiting Liu, Prajwal Gatti, Siddhant Bansal, Kevin Flanagan, Jacob Chalk, Zhifan Zhu, Rhodri Guerrier, Fahd Abdelazim, Bin Zhu, Davide Moltisanti, Michael Wray, Hazel Doughty, Dima Damen Jun 2025

Hd-Epic: A Highly-Detailed Egocentric Video Dataset, Toby Perrett, Ahmad Darkhalil, Saptarshi Sinha, Omar Emara, Sam Pollard, Kranti Kumar Parida, Kaiting Liu, Prajwal Gatti, Siddhant Bansal, Kevin Flanagan, Jacob Chalk, Zhifan Zhu, Rhodri Guerrier, Fahd Abdelazim, Bin Zhu, Davide Moltisanti, Michael Wray, Hazel Doughty, Dima Damen

Research Collection School Of Computing and Information Systems

We present a validation dataset of newly-collected kitchenbased egocentric videos, manually annotated with highly detailed and interconnected ground-truth labels covering: recipe steps, fine-grained actions, ingredients with nutritional values, moving objects, and audio annotations. Importantly, all annotations are grounded in 3D through digital twinning of the scene, fixtures, object locations, and primed with gaze. Footage is collected from unscripted recordings in diverse home environments, making HDEPIC the first dataset collected in-the-wild but with detailed annotations matching those in controlled lab environments. We show the potential of our highly-detailed annotations through a challenging VQA benchmark of 26K questions assessing the capability to …


A Digital Dive: Redesigning The Cabrillo High School Aquarium Website, Jacob V. Cacho Jun 2025

A Digital Dive: Redesigning The Cabrillo High School Aquarium Website, Jacob V. Cacho

Graphic Communication

Tucked away on the Central Coast in Lompoc, you’ll find the Cabrillo High School (CHS) Aquarium. Started in 1986, the CHS Aquarium is the only high school aquarium of its kind in the nation run entirely by high school students. This 10,000+ square foot aquarium serves an underserved community at a Title I school, where students manage all aspects of animal care, nutrition, breeding, educational curriculum development, and visitor tours.

This program is truly one-of-a-kind and deserves the spotlight for just how unique it is. As a CHS graduate, I felt the current website lacked in many areas and could …


Status And Distribution Of Diseases Caused By Phytoplasmas In Africa, Shakiru Adewale Kazeem, Agnieszka Zwolińska, Joseph Mulema, Akindele Oluwole Ogunfunmilayo, Shina Salihu, Joy Oluchi Nwogwugwu, Inusa Jacob Ajene, Justina Folasayo Ogunsola, Adedapo Olutola Adediji, Olubusola Fehintola Oduwaye, Kouamé Daniel Kra, Mustafa Ojonuba Jibrin, Wei Wei Jun 2025

Status And Distribution Of Diseases Caused By Phytoplasmas In Africa, Shakiru Adewale Kazeem, Agnieszka Zwolińska, Joseph Mulema, Akindele Oluwole Ogunfunmilayo, Shina Salihu, Joy Oluchi Nwogwugwu, Inusa Jacob Ajene, Justina Folasayo Ogunsola, Adedapo Olutola Adediji, Olubusola Fehintola Oduwaye, Kouamé Daniel Kra, Mustafa Ojonuba Jibrin, Wei Wei

All Peer-Reviewed Publications

Phytoplasma (“Candidatus Phytoplasma” species) diseases have been reported globally to severely limit the productivity of a wide range of economically important crops and wild plants causing different yellows-type diseases. With new molecular detection techniques, several unknown and known diseases with uncertain etiologies or attributed to other pathogens have been identified as being caused by Phytoplasmas. In Africa, Phytoplasmas have been reported in association with diseases in a broad range of host plant species. However, the few reports of Phytoplasma occurrence in Africa have not been collated together to determine the status in different countries of the continent. Thus, this paper …


Biochar Suppresses Growth, Pupation And Eclosion Success Of A Specialist (Manduca Sexta) And A Generalist (Spodoptera Frugiperda) Insect Herbivore, Nischal Wagle, Soumya Unnikrishnan, Satinderpal Kaur, Engil Isadora Pujol Pereira, Rupesh R. Kariyat Jun 2025

Biochar Suppresses Growth, Pupation And Eclosion Success Of A Specialist (Manduca Sexta) And A Generalist (Spodoptera Frugiperda) Insect Herbivore, Nischal Wagle, Soumya Unnikrishnan, Satinderpal Kaur, Engil Isadora Pujol Pereira, Rupesh R. Kariyat

School of Earth, Environmental, & Marine Sciences Faculty Publications

Biochar is a charcoal-like substance made by the pyrolysis of organic material from agricultural and forestry waste. While biochar is well documented for altering soil physicochemical conditions, few studies have investigated its possible effects on the management of arthropod pests. Tobacco hornworm (Manduca sexta) and fall armyworm (Spodoptera frugiperda, FAW) are specialist and generalist insect herbivores respectively, that can cause significant defoliation in natural and agricultural ecosystems. In this study, we examined whether walnut shell biochar can affect growth and development of these herbivores. Specifically, we investigated how biochar influences parameters such as mass gain, length …


California Kelp Forests: An Analysis Of Macrocystis Pyrifera And Nereocystis Luetkeana Restoration After Decades Of Decline, Gabrielle K. Farrer May 2025

California Kelp Forests: An Analysis Of Macrocystis Pyrifera And Nereocystis Luetkeana Restoration After Decades Of Decline, Gabrielle K. Farrer

Master's Projects and Capstones

California’s kelp forests are some of the most biodiverse and productive ecosystems on the planet. Centuries of anthropogenic degradation via habitat destruction and climate change have culminated in decreased kelp forest habitat at an accelerated rate since at least the 1850s (Scarborough et al. 2022; Rogers-Bennett & Catton, 2019; Kumagai et al. 2024; Smith et al. 2023). This study synthesizes major threats, past and present, to California’s kelp forests, including the overharvesting of multiple species, pollution from coastal development, and climate change impacts. I also examine current management practices regarding kelp forests such as the use of marine protected areas …


Soybean Oil-Derived Acrylate/Methacrylate Ether For High Resolution Additive Manufacturing (3d Printing) Technology, Tanuj Patel May 2025

Soybean Oil-Derived Acrylate/Methacrylate Ether For High Resolution Additive Manufacturing (3d Printing) Technology, Tanuj Patel

Electronic Theses & Dissertations

Additive Manufacturing is one of the rapidly developing techniques, as industries continue to explore new ways to create prototypes and end-use parts, one of the significant challenges that remains is the reliance on petroleum-based plastics for 3D printing, especially in the production of photocurable resins. that may be used to prototype complex structures and sophisticated geometries that are typically challenging to produce with conventional methods. Thus, replacing petroleum-based plastics with renewable resources is increasingly important for additive manufacturing (3D printing) of photocurable resins. The use of bio-based renewable resources in AM is a feasible alternative to traditional petroleum-based plastics. Henceforth, …


Real-World Implementation Of A Noninvasive, Ai-Augmented, Anemia-Screening Smartphone App And Personalization For Hemoglobin Level Self-Monitoring, Robert G. Mannino, Julie Sullivan, Jennifer K. Frediani, Paul George, Jeremy Whitson, James Tumlin, L. Andrew Lyon, Erika A. Tyburski, Wilbur A. Lam May 2025

Real-World Implementation Of A Noninvasive, Ai-Augmented, Anemia-Screening Smartphone App And Personalization For Hemoglobin Level Self-Monitoring, Robert G. Mannino, Julie Sullivan, Jennifer K. Frediani, Paul George, Jeremy Whitson, James Tumlin, L. Andrew Lyon, Erika A. Tyburski, Wilbur A. Lam

Engineering Faculty Articles and Research

Anemia, characterized by low blood hemoglobin (Hgb) levels, afflicts >2 billion individuals worldwide. Here, we report real-world data generated by a smartphone app that noninvasively screens for anemia using only “fingernail selfies.” App data for anemia screening were obtained from >1.4 million uses across the United States enabling geographic mapping of Hgb levels. Of those, 9,061 users also self-reported complete blood count Hgb levels for comparison, resulting in accuracy and performance that match gold standard laboratory testing and a sensitivity and specificity of 89% and 93%, respectively, when using an anemia cutoff of 12.5 g/dL. Geotagged data enabled construction of …


Chemical Reversal Of Beta-Lactam Resistance And Induction Of Hyper-Susceptibility In Pseudomonas Aeruginosa By Limiting Horizontal Gene Transfer Under Beta-Lactam Stress, Aimee Iradukunda May 2025

Chemical Reversal Of Beta-Lactam Resistance And Induction Of Hyper-Susceptibility In Pseudomonas Aeruginosa By Limiting Horizontal Gene Transfer Under Beta-Lactam Stress, Aimee Iradukunda

Dissertations - ALL

The emergence of antibiotic resistance poses a significant threat to global health, with certain bacterial strains evolving to resist multiple drugs. Urgent action is necessary to develop new antibacterial agents that effectively target these resistant strains; however, no new classes of antibiotics have been approved in recent decades. This research employs innovative biological tools to identify and highlight factors influencing resistance dynamics. Additionally, this study refines the novel approach by utilizing adjuvants to chemically repurpose existing antibiotics and improve their effectiveness against antibiotic-resistant strains. Pseudomonas aeruginosa, recognized for its adaptability, persistent infections—especially in cystic fibrosis patients—and widespread antibiotic resistance, serves …


Challenges Us Study Abroad Students Face When Acculturating To A Foreign Food Environment, Sydney C. Davis May 2025

Challenges Us Study Abroad Students Face When Acculturating To A Foreign Food Environment, Sydney C. Davis

Honors Theses

Studying abroad presents a unique opportunity for college students to immerse themselves in new cultures, including experiencing different food environments and dietary customs. However, adapting to a foreign food culture can pose various challenges that impact students’ overall health, eating behaviors, and study abroad experiences. The purpose of this study to develop a survey instrument designed to investigate the extent to which U.S. study abroad students embrace, accept, and face challenges with different aspects of Italian food culture, using the Social Ecological Model (SEM) as a guiding framework. Initial survey items were developed with information obtained from focus group discussions …


Dynamic Riskscapes For Prey: Disentangling The Impact Of Human And Cougar Presence On Deer Behavior Using Gps Smartphone Locations, Heather N. Abernathy, Mark A. Ditmer, David C. Stoner, Kent R. Hersey, Kathryn A. Schoenecker, Pat J. Jackson, Kristin N. Engebretsen, Julie K. Young, George Wittemyer May 2025

Dynamic Riskscapes For Prey: Disentangling The Impact Of Human And Cougar Presence On Deer Behavior Using Gps Smartphone Locations, Heather N. Abernathy, Mark A. Ditmer, David C. Stoner, Kent R. Hersey, Kathryn A. Schoenecker, Pat J. Jackson, Kristin N. Engebretsen, Julie K. Young, George Wittemyer

Wildland Resources Faculty Publications

Prey species adjust their behavior along human-use gradients by balancing risks from predators and humans. During hunting seasons, prey often exhibit strong antipredator responses to humans but may develop tolerance in suburban areas to exploit human-mediated resources. Additionally, areas with high human activity may offer reduced predation risk if apex predators avoid such locations. This study examined mule deer Odocoileus hemionus behavioral responses to risks from humans and their primary predators, cougars Puma concolor, contextualized by differences in risk levels between study sites, individual risk exposure, and human habituation. We framed our investigation using three non-mutually exclusive hypotheses: (H1) …


Evaluation Of Tree Legumes Species At Different Agroclimatic Zones Of Indonesia, Mas'ud Panjaitan, R Jessop, W W. Stur May 2025

Evaluation Of Tree Legumes Species At Different Agroclimatic Zones Of Indonesia, Mas'ud Panjaitan, R Jessop, W W. Stur

IGC Proceedings (1977-2023)

The population of Indonesia is over 145 million and more than 56 % of them earn their living from agriculture (Bi. Stat. Ind., 1983). A major problem in the development of improved animal production has been the shortage of feed and the generally low nutritive value of tropical forages which limit livestock pro­duction in Indonesia (Asian Agriculture Survey, 1969). The production of feed of adequate quality for ruminants is an important consideration particularly for small holders. In many situations, nitrogen fixing legume trees can be used as a high protein feed supplement which improves the utilization of grasses and crop …


Valeur Nutritive D'Un Parcours Mixte A Acacia Cyanophylla, Atriplex Nummularia Et Medicago Arborea, Y Saadani, C Kayouli May 2025

Valeur Nutritive D'Un Parcours Mixte A Acacia Cyanophylla, Atriplex Nummularia Et Medicago Arborea, Y Saadani, C Kayouli

IGC Proceedings (1977-2023)

II existe tres peu de donnees concernant la valeur nutritive des arbustes fourragers ; les rares etudes realisees en Tunisie ont porte surtout sur leur productivite, la charge animale et sur leur appetence (Hamrouni et Sarson, 1975; Ben Boubaker, 1985). L'objectif de ce travail est d'etudier la valeur nutritive des feuilles et brindilles d' Acacia cyanophylla, d' A triplex nummula­ria et de Medicago arborea ainsi que leur contribution dans la ration de caprins et d'ovins.


Forage Production And Nutritive Value Of Leucanea Leucoephala In Southern Puerto Rico, L E. Tergas, R Milton Martinez, A V. Mendez Cruz May 2025

Forage Production And Nutritive Value Of Leucanea Leucoephala In Southern Puerto Rico, L E. Tergas, R Milton Martinez, A V. Mendez Cruz

IGC Proceedings (1977-2023)

Leucaena leucocephala (L.) is a perennial schrub native to Mexico, Central America and the Caribbean, considered by investigators as a valuable forage legume because of its capacity for high production of digestible forage with a high protein content and tolerance to drought in semiarid regions with annual rainfall less than 1,000 mm (Skerman, 1977). The soil fertility of the semiarid region in southern Puerto Rico is adequate, but rainfall distribution is limiting for forage production and nutritive value. There is a demand for a suit­able and inexpensive source of high quality forage to improve the diet of the grazing cattle …


Apparent Digestibility, Dynamics Of Rumen Fermentation And Sites Of Digestion Of Hays Of Leucaena Leucocephala (Lam) De Wit Cv. Peru, N M. Rodreiguez, I Borges May 2025

Apparent Digestibility, Dynamics Of Rumen Fermentation And Sites Of Digestion Of Hays Of Leucaena Leucocephala (Lam) De Wit Cv. Peru, N M. Rodreiguez, I Borges

IGC Proceedings (1977-2023)

Protein deficiency, among others, is a common problem for livestock production in tropical regions. The use oflegumes has been suggested as a solution and Leucaena leucocephala has shown a great potential due to its capacity of nitrogen (N) fix­ation and dry matter (DM) production (NAS, 1984). However, very little is known about its nutritive value regarding its protein-energy balance and the process of digestion. The present work aimed the evaluation of the nutritive value of hays of Leucaena leucocephala cut at two stages of growth, through trials of apparent digestibility, dynamics of rumen fer­mentation and partition of digestion.


In Situ Degradation Of Cell Wall Neutral Sugars Of Normal And Brown Midrib Sorghum X Sudangrass Hybrids, K J. Moore, J O. Fritz, E H. Jaster May 2025

In Situ Degradation Of Cell Wall Neutral Sugars Of Normal And Brown Midrib Sorghum X Sudangrass Hybrids, K J. Moore, J O. Fritz, E H. Jaster

IGC Proceedings (1977-2023)

The nutritive value of forage for ruminants is limited by the digestibility of the complex polysaccharides cellulose and hemicellulose by rumen microbes. In grasses, the polysacchar­ide fraction of the cell wall is composed largely of polymers of neutral sugars and to a lesser extent uronic acids. Cellulose is a high molecular weight linear polymer of B-1 ➔ 4) linked D­gluco-pyranose units. Hemicellulose is a complex mixture of linear and branched-chain heteropolymers containing xylose, arabmose, mannose, galactose, glucose, and uronic acids (Van Soest, 1982). Lignification of the cell wall is a primary factor limiting the digestion of cell wall polysaccharides. Close …


Feed Evaluation Using Mobile Dacron Bags And Influences Of The Diet Composition, H Anzola, F N. Owens May 2025

Feed Evaluation Using Mobile Dacron Bags And Influences Of The Diet Composition, H Anzola, F N. Owens

IGC Proceedings (1977-2023)

The Mobile Nylon Bag (MNB) technique has been used successfully in protein nutrition studies with swine (Sauer et al., 1983) to determine amino acid availability from protein in specific feedstuffs. Canadian researchers also have tested this technique to predict site of digestion in ruminants (Kirkpatrick and Kennelly, 1987). Differences in small intestinal digestion may explain why animal responses differ to dietary protein sources which have similar ruminal escape values (Owens, 1986). The MNB holds promise to appraise the intestinal avail­ability of undegraded dietary protein though further develop­mel).t and testing are needed. The objective of this experiment was to examine the …


Sites Of Digestion Of Nitrogen Of Hays Made With The Tropical Legume Neonotonia Wightii, R R. Vera, E A. Pizarro, A Toscano, N M. Rodriguez May 2025

Sites Of Digestion Of Nitrogen Of Hays Made With The Tropical Legume Neonotonia Wightii, R R. Vera, E A. Pizarro, A Toscano, N M. Rodriguez

IGC Proceedings (1977-2023)

Tropical pasture species are of well-known lower quality than temperate species and there is evidence that some tropical legumes may contain antiquality factors that reduce further their nutritive value. Nonetheless, the nutritive value of Neonotonia wightii is generally moderate to high (Pizarro et al., 1983 ; Ribeiro et al., 1980), although there is little information on the factors that affect its quality, and none on the rate and sites of digestion within the gastrointestinal tract of ruminants. The aim of the work reported here was to examine the effect of age on the chemical composition, apparent digestibility and sites of …


Nutritive Value Of Perennial Ryegrass Swards Grazed By Sheep In Autumn In The Uk, J A. Milne, H Dove, A M. Sibbald May 2025

Nutritive Value Of Perennial Ryegrass Swards Grazed By Sheep In Autumn In The Uk, J A. Milne, H Dove, A M. Sibbald

IGC Proceedings (1977-2023)

A knowledge of the nutrient supply from grazed herbage for ewes in the autumn in N. Europe is required to predict the consequences for their subsequent reproductive performance. Herbage intake has been found to be positively related to sward height over this period at low sward heights but there is no information over a wider range of heights, on the amounts of non-ammonia nitrogen (NAN) available for absorption in the small intestine nor on the digestion of organic matter in the rumen. Experiments on frozen or artificially dried herbage harvested in the autumn have given variable results for the amounts …


Comparison Of Laboratory Methods For Estimating Herbage Digestibility, Francoise Riviere, P Maupetit, G Blanchard May 2025

Comparison Of Laboratory Methods For Estimating Herbage Digestibility, Francoise Riviere, P Maupetit, G Blanchard

IGC Proceedings (1977-2023)

Forages are an important source of nutrients for ruminants and recently interest has been shown in using forages for a greater proportion of the nutrients in ruminant production. The feeding value of forages mainly depends on their digestible organic matter contents. Feeding of forages to animals is the most accurate method of evaluation but such trials are expens­ive and very slow. Many laboratory procedures have been developped for esti­mating forage nutritive value. Recently, near infrared reflec­tance has been developped to provide a fast and reliable alter­native method. The aim of the study is to compare laboratory methods of forage evaluation …