Digital Commons Network^™

Spatial Transcriptome Reveals Histology-Correlated Immune Signature Learnt By Deep Learning Attention Mechanism On H&E-Stained Images For Ovarian Cancer Prognosis, Chun Wai Ng, Kwong-Kwok Wong, Barrett C Lawson, Sammy Ferri-Borgogno, Samuel C Mok

Faculty, Staff and Student Publications

Background: The ability to predict the prognosis of patients with ovarian cancer can greatly improve disease management. However, the knowledge on the mechanism of the prediction is limited. We sought to deconvolute the attention feature learnt by a deep learning convolutional neural networks trained with whole-slide images (WSIs) of hematoxylin-and-eosin (H&E)-stained tumor samples using spatial transcriptomic data.

Methods: In this study, 773 WSIs of H&E-stained tumor sections from 335 patients with treatment naïve high-grade serous ovarian cancer who were included in The Cancer Genome Atlas (TCGA) Pan-Cancer study were used to train, and validate, and to test a ResNet101 CNN …

Animal-Based Economy And Local Ecology: The Early Bronze Age Ii Fauna From Qiryat Ata––Area S (Pp. 99–109), Edward F. Maher

'Atiqot

The species exploited at Qiryat Ata are dominated by domestic animals, the most common being sheep and goats. Very few wild animals are present in the assemblage, comprising less than 6% of the identifiable remains, including fallow deer, wild pig and sea turtle.

Mollusk Shells From Bet She’An (Youth Hostel) (Hebrew Pp.149–151; English Summary, P. 132*), Frida Ben-Ami

'Atiqot

Five mollusk shells were retrieved from the excavation at the site of the Bet She’an Youth Hostel: Hexaplex trunculus, Glycymeris glycymeris, Spondylus gaederopus, Charonia sp., Tridacna maxima. Four shells originated in the Mediterranean Sea, and one, in the Red Sea. One specimen, the Charonia sp., is not found along the shore of Israel, and was most probably collected somewhere else in the Mediterranean basin, possibly Italy. One of the shells found at the site, H. trunculus, is known to have been used for dyeing in biblical times. The other four were used as decorative ornaments (beads), or as storage containers, …

Human Skeletal Remains From Late Roman Tombs On Sallah Ed-Din Street, Jerusalem (Pp. 73–79), Yossi Nagar

'Atiqot

Poorly preserved human skeletal remains, belonging to at least 77 individuals, were recovered from Burial Cave I and 43 rock-cut cist tombs on Sallah ed-Din Street. Most of the cist tombs contained a single primary burial. Pathologies in the sample include three traumatic lesions, which are relatively common in skeletal populations. Individuals from both sexes were almost equally represented; infants were underrepresented. The burials indicate a civilian population, similar to other reported Roman-Byzantine populations in the country.

Faunal Remains From The 1994–1996 Excavations At The Temple Mount, Jerusalem (Pp. 19–34), Ronny Reich, Ya'akov Billig, Dalia Hakker-Orion, Omri Lernau

'Atiqot

This study focused on the faunal remains (N = 3618) retrieved from three strata unearthed above the Second Temple-period stone-paved road along the southern part of the western wall of the Temple Mount. The three strata date to the Early Roman (first century BCE and first century CE–70 CE; Stratum 4), the Late Roman–Byzantine (second–sixth centuries CE; Stratum 3) and the Early Islamic (seventh–eighth centuries CE; Stratum 2) periods. The faunal remains from the Early Roman period reflect the large amounts of waste created by the various populations in the city, with a predominance of Jewish pilgrims. Following the destruction …

In Silico Analysis Of Cd40 Mutations And Their Implications For Quinoline-Benzoic Acid Derivatives Based Therapy In Graves' Disease, Luluk Yunaini, Diyah Kristanty, Puji Sari, Surya Dwira, Dwi Anita Suryandari, Arleni Bustami

Indonesian Journal of Medical Chemistry and Bioinformatics

Graves' disease is an autoimmune disorder in which the CD40-CD154 interaction plays a critical role in T-cell activation. In this study, in silico methods were employed to analyze the binding interactions of quinoline-benzoic acid derivatives (NSB, FSB, and NQB) with the CD40 receptor and to investigate the implications of specific CD40 mutations for drug efficacy. In this reseach conducted by molecular simulation approach with molecular docking Results Mutation analysis of CD40 identified alterations in key residues, such as R203C, which may impact ligand-independent activation and downstream TRAF binding, crucial for signal transduction. These findings highlight the therapeutic potential of quinoline-benzoic …

A Global Dataset Of Nitrogen Fixation Rates Across Inland And Coastal Waters, Robinson W. Fulweiler, Megan E. Berberich, Shelby A. Rinehart, Jason M. Taylor, Michelle Catherine Kelly, Nicholas E. Ray, Autumn Oczkowski, Sawyer J. Balint, Alexandra H. Geisser, Catherine R. Mahoney, Mar Benavides, Matthew J. Church, Brianna Loeks, Silvia E. Newell, Malin Olofsson, Jimmy C. Oppong, Sarah S. Roley, Carmella Vizza, Samuel T. Wilson, Peter M. Groffman, J. Thad Scott, Amy Marcarelli

Michigan Tech Publications

Biological nitrogen fixation is the conversion of dinitrogen (N2) gas into bioavailable nitrogen by microorganisms with consequences for primary production, ecosystem function, and global climate. Here we present a compiled dataset of 4793 nitrogen fixation (N2-fixation) rates measured in the water column and benthos of inland and coastal systems via the acetylene reduction assay, 15N2 labeling, or N2/Ar technique. While the data are distributed across seven continents, most observations (88%) are from the northern hemisphere. 15N2 labeling accounted for 67% of water column measurements, while the acetylene reduction assay accounted for 81% of benthic N2-fixation observations. Dataset median area-, volume-, …

Development And Validation Of Rapid Edna Detection Method For Yellow Mud Turtle, Kinosternon Flavescens: A Field Study In South Texas, Usa, Sakib Tahmid Rishan, Richard Kline, Md Saydur Rahman

School of Earth, Environmental, & Marine Sciences Faculty Publications

The conservation of freshwater turtle species depends on precise and effective monitoring techniques. Environmental DNA (eDNA) analysis is a potential method for identifying cryptic and elusive turtle species in aquatic ecosystems. eDNA analysis can help to identify key regions for conservation efforts and monitor changes in population levels over time. This study aims to evaluate the effectiveness of a rapid eDNA detection method for the yellow mud turtle (Kinosternon flavescens, an indicator species that is endangered in some states in the USA), which inhabits local oxbow lakes (e.g., resacas) in Cameron County, South Texas. A species-specific nested PCR …

Inhibition Of Vascular Smooth Muscle Cell Perk/Atf4 Er Stress Signaling Protects Against Abdominal Aortic Aneurysms, Brennan Callow, Xiaobing He, Nicholas Juriga, Kevin D Mangum, Amrita Joshi, Xianying Xing, Andrea Obi, Abhijnan Chattopadhyay, Dianna M Milewicz, Mary X O'Riordan, Johann Gudjonsson, Katherine Gallagher, Frank M Davis

Faculty, Staff and Student Publications

Abdominal aortic aneurysms (AAA) are a life-threatening cardiovascular disease for which there is a lack of effective therapy preventing aortic rupture. During AAA formation, pathological vascular remodeling is driven by vascular smooth muscle cell (VSMC) dysfunction and apoptosis, for which the mechanisms regulating loss of VSMCs within the aortic wall remain poorly defined. Using single-cell RNA-Seq of human AAA tissues, we identified increased activation of the endoplasmic reticulum stress response pathway, PERK/eIF2α/ATF4, in aortic VSMCs resulting in upregulation of an apoptotic cellular response. Mechanistically, we reported that aberrant TNF-α activity within the aortic wall induces VSMC ATF4 activation through the …

Fos Expression In The Periaqueductal Gray, But Not The Ventromedial Hypothalamus, Is Correlated With Psychosocial Stress-Induced Cocaine-Seeking Behavior In Rats, Nicole M Hinds, Ireneusz D Wojtas, Desta M Pulley, Stephany J Mcdonald, Colton D Spencer, Milena Sudarikov, Nicole E Hubbard, Colin M Kulick-Soper, Samantha De Guzman, Sara Hayden, Jessica J Debski, Bianca Patel, Douglas P Fox, Daniel F Manvich

Rowan-Virtua School of Osteopathic Medicine Departmental Research

Psychosocial stressors are known to promote cocaine craving and relapse in humans but are infrequently employed in preclinical relapse models. Consequently, the underlying neural circuitry by which these stressors drive cocaine seeking has not been thoroughly explored. Using Fos expression analyses, we sought to examine whether the ventromedial hypothalamus (VMH) or periaqueductal gray (PAG), two critical components of the brain's hypothalamic defense system, are activated during psychosocial stress-induced cocaine seeking. Adult male and female rats self-administered cocaine (0.5 mg/kg/inf IV, fixed-ratio 1 schedule, 2 h/session) over 20 sessions. On sessions 11, 14, 17, and 20, a tactile cue was present …

Mitochondrial Mrna And The Small Subunit Rrna In Budding Yeasts Undergo 3'-End Processing At Conserved Species-Specific Elements, Michael Anikin, Michael F Henry, Viktoria Hodorova, Hristo B Houbaviy, Jozef Nosek, Dimitri G Pestov, Dmitriy A Markov

Rowan-Virtua School of Osteopathic Medicine Departmental Research

Respiration in eukaryotes depends on mitochondrial protein synthesis, which is performed by organelle-specific ribosomes translating organelle-encoded mRNAs. Although RNA maturation and stability are central events controlling mitochondrial gene expression, many of the molecular details in this pathway remain elusive. These include

Climate Influence On Both Spatial And Temporal Patterns Of Rocky Intertidal Community Structure In San Diego, California, Emily Jenkins

Theses

The rocky intertidal ecosystem, the coastal area between high and low tides, serves as a critical buffer between land and sea. This ecosystem supports a diverse array of species and provides rich opportunities for exploration and education. With the influence of climate change, this ecosystem faces significant shifts in species distribution, resilience and recovery from environmental disturbances, as well as habitat loss (Jackson & McIlvenny 2011; Jueterbock et al. 2013; Menge & Gravem 2022; Rilov et al. 2021; Sagarin & Barry 1999). Between 2014-2016, climate anomalies El Niño (ENSO) and the Pacific Decadal Oscillation (PDO) combined to create a period …

Understanding Market Outlooks, Elliott James Dennis

Cornhusker Economics

As 2024 has concluded, many industry analysts will reflect on the market trends and forces that shaped 2024 to make improved decision making in 2025. This is a pivotal time to evaluate the factors influencing commodity markets and plan for the future. Market outlooks play a vital role in this process, offering agricultural producers and industry stakeholders valuable insights into price trends, production forecasts, and market dynamics. By analyzing data from government agencies, universities, and private firms, these outlooks help users anticipate and navigate market fluctuations, whether through short-term forecasts or long-term projections spanning decades. With advances in technology and …

Community-Centered Climate Resilience Strategies For Agriculture In Chile's Los Lagos, Asa B. Stone, Cristián Kremer F., Mark C. Stone

Cornhusker Economics

Community-centered approaches using the SETS framework facilitate equitable community-academia partnerships that co-create climate resilience strategies. By integrating local insights with academic research ethically and equitably, PLL aims to develop evidence-based, culturally relevant, and technologically feasible strategies. This holistic approach not only enhances community resilience but also ensures the sustainable management of water resources in the Los Lagos Region.

Structure And Mechanism Of Biosynthesis Of Streptococcus Mutans Cell Wall Polysaccharide., Jeffrey S. Rush, Svetlana Zamakhaeva, Nicholas R Murner, Pan Deng, Andrew J Morris, Cameron W Kenner, Ian Black, Christian Heiss, Parastoo Azadi, Konstantin V Korotkov, Göran Widmalm, Natalia Korotkova

Molecular and Cellular Biochemistry Faculty Publications

Streptococcus mutans, the causative agent of human dental caries, expresses a cell wall attached Serotype c-specific Carbohydrate (SCC) that is critical for cell viability. SCC consists of a polyrhamnose backbone of →3)α-Rha(1 → 2)α-Rha(1→ repeats with glucose (Glc) side-chains and glycerol phosphate (GroP) decorations. This study reveals that SCC has one predominant and two more minor Glc modifications. The predominant Glc modification, α-Glc, attached to position 2 of 3-rhamnose, is installed by SccN and SccM glycosyltransferases and is the site of the GroP addition. The minor Glc modifications are β-Glc linked to position 4 of 3-rhamnose installed by SccP and …

Optimized Methods To Quantify Tumor Treating Fields (Ttfields)-Induced Permeabilization Of Glioblastoma Cell Membranes, Melisa Martinez-Paniagua, Sabbir Khan, Nikita W Henning, Sri Vaishnavi Konagalla, Chirag B Patel

Faculty, Staff and Student Publications

Glioblastoma (GBM) is a lethal primary brain cancer with a 5.6% five-year survival rate. Tumor treating fields (TTFields) are alternating low-intensity electric fields that have demonstrated a GBM patient survival benefit. We previously reported that 0.5-24 h of TTFields exposure resulted in an increased uptake of FITC-dextran fluorescent probes (4-20 kDa) in human GBM cells. However, this approach, in which a fluorescence plate-based detector is used to evaluate cells attached to glass coverslips, cannot distinguish FITC-dextran uptake in live vs. dead cells. The goal of the study was to report the optimization and validation of two independent methods to quantify …

Stratification System With Dual Human Endogenous Retroviruses For Predicting Immunotherapy Efficacy In Metastatic Clear-Cell Renal Cell Carcinoma, Xiaofan Lu, Yann-Alexandre Vano, Xiaoping Su, Virginie Verkarre, Cheng-Ming Sun, Wenxuan Cheng, Li Xu, Fangrong Yan, Salma Kotti, Wolf Hervé Fridman, Catherine Sautes-Fridman, Stéphane Oudard, Gabriel G Malouf

Faculty, Staff and Student Publications

Background: Endogenous retrovirus (ERV) elements are genomic footprints of ancestral retroviral infections within the human genome. While the dysregulation of ERV transcription has been linked to immune cell infiltration in various cancers, its relationship with immune checkpoint inhibitor (ICI) response in solid tumors, particularly metastatic clear-cell renal cell carcinoma (ccRCC), remains inadequately explored.

Methods: This study analyzed patients with metastatic ccRCC from two prospective clinical trials, encompassing 181 patients receiving nivolumab in the CheckMate trials (-009 to -010 and -025) and 48 patients treated with the ipilimumab-nivolumab combination in the BIONIKK trial. ERV expression was quantified using the ERVmap algorithm …

A Deconvolution Framework That Uses Single-Cell Sequencing Plus A Small Benchmark Data Set For Accurate Analysis Of Cell Type Ratios In Complex Tissue Samples, Shuai Guo, Xiaoqian Liu, Xuesen Cheng, Yujie Jiang, Shuangxi Ji, Qingnan Liang, Andrew Koval, Yumei Li, Leah A Owen, Ivana K Kim, Ana Aparicio, Sanghoon Lee, Anil K Sood, Scott Kopetz, John Paul Shen, John N Weinstein, Margaret M Deangelis, Rui Chen, Wenyi Wang

Faculty, Staff and Student Publications

Bulk deconvolution with single-cell/nucleus RNA-seq data is critical for understanding heterogeneity in complex biological samples, yet the technological discrepancy across sequencing platforms limits deconvolution accuracy. To address this, we utilize an experimental design to match inter-platform biological signals, hence revealing the technological discrepancy, and then develop a deconvolution framework called DeMixSC using this well-matched, that is, benchmark, data. Built upon a novel weighted nonnegative least-squares framework, DeMixSC identifies and adjusts genes with high technological discrepancy and aligns the benchmark data with large patient cohorts of matched-tissue-type for large-scale deconvolution. Our results using two benchmark data sets of healthy retinas and …

Milk Yield Of Cows With Different Genetic Potential On Grass And Grass-Legume Tropical Pastures, C E. Lascano, P Avila

IGC Proceedings (1977-2023)

A grazing experiment was carried out at CIAT's Quilichao research station to assess the effect of legumes selected for acid soils on milk production of cows with different genetic potential. Pastures of Brahiaria dictyoneura cv. Llanero and Andropogen gayanus cv. Carimagua l, alone and in association with Centrosema acutifolium (CIAT 5568) and C. macrocarpum (CJAT 5713), were grazed by Holstein and Zebu crossbred cows using a Latin square crossover design. Fat corrected milk (FCM) yield of Holstein cows was 17 and 19% higher in the associations of B. dictyoneura and A. gayanus, respectively, than in the grass-only pastures. With the …

Fattening Heifers On Nitrogen Fertilized And Irrigated Pastures: A Productive And Sustainable System For The Tropics?, F Champanhet, M Mahieu

IGC Proceedings (1977-2023)

Beef production from nitrogen-fertilised and irrigated pastures was studied for 4,S years on vertisols, South Martinique (rainfall 1400 mm). Digitaria decumbens (pangola) pastures received 230��7S-ISO kg/ha/year N-P·K and were rotationally grazed (S days grazed, 30 days rested) all year round with a fixed stocking rate (6.6 heifers/ha). Mean live-weight gains were: 1121 kg/ha/year and 170 kg/head/ year. Pangola showed good persistence and cover at the end of the experiment exceeded 9S%, It is concluded that heifers fattening on nitrogen-fertilised pastures is a productive and stable system.

Comparative Use Of Digitaria Decumbens And Cynodon Nlemfuensis By Local Suckling Ewes In Martinque (Fwi), Maryline Boval, Gisele Alexandre, M Mahieu, P Cruz, M Meuret

IGC Proceedings (1977-2023)

Pastures of Digitaria decumbens (Dd) and Cynodon nlemfuensis (Cn) were each grazed by 64 native suckling ewes ( 40 ewes/ha) in Martinique. Forage characteristics, ewe feeding behaviour and lamb growth were studied. The available herbage mass (kg DMJLW0-75/day) was lower for the Dd pastures than for the Cn pastures: 295 v. 355 for the leaves (P<0.05) and 820 v, 1360 for the stems (P<0.01), respectively. There was no difference in the diurnal activities (grazing, ruminating) between the ewes in the 2 groups. Number of bites/min was higher on Dd pasture than that for Cn: 31 v. 26 (P<0.001), Pre­weaning daily weight gain (g/day) was higher for the Dd lambs group than for Cn: 170 v. 140 (P<0.01). The lamb mortality rate(%) was respectively: 15 v. 27 (P<0.05). Pasture management problems are discussed.

Stockpiling Of Brachiaria Decumbens For Steer Maintenance During The Dry Season, Esther G. Cardoso, V.P B. Euclides, J.M Da Silva

IGC Proceedings (1977-2023)

A Brachiaria decumbens pasture was evaluated in a factorial experiment (2 stocking rates and 2 pasture managements). Eight steers averaging 370 kg live weight (LW) were allocated to the paddocks at the beginning of the wet season ( 1 December). For the deferred management treatment, half of the area was closed off at the end of the rainy season ( 15 March to 15 June) for utilisation as stockpiled feed during the dry season (15 June to 30 October). B. decumbems was capable of fattening Nellore steers during the rainy ·season, but maintained steer live weight (LW) only in the …

Seasonal Changes In The Chemical Composition Of Cultivated Tropical Grasses In The Savannas Of Brazil, M.C M. Macedo, V.P B. Euclides, M.P De Oliveira

IGC Proceedings (1977-2023)

Five tropical grasses; Brachiaria brizantha cv. Marandu, B, decumbens cv. Basilisk, Panicum maximum cv. Coloniilo, P. maximum cv, Tobiatil, P. maximum cv. Tanzania-I, were planted on a dark red latosol (Oxisol) and grazed for 3 rainy and 3 dry seasons . The original savanna vegetation was removed, the soil cultivated and fertilised with 1000 kg/ha of dolomitic limestone, 350 kg/ha of single superphosphate, 100 kg/ha of KCI and 40 kg/ha of fritted traced elements. Treatments were arranged in a RCB design with 3 replicates. Paddocks were 1.5 ha. Grazing pressure was adjusted to approximately 8 or 15 kg of …

Evaluation Of Panicum Maximum Cultivars Under Grazing, V.P B. Euclides, M.C M. Macedo, A Vieira, M P. Oliveira

IGC Proceedings (1977-2023)

A grazing trial was conducted in Brazil, for a 3-year period, to study animal production from Panicum maximum cultivars (Coloniao, Tobiatii and Tanz5nia-1). Three 1.5-hn paddocks of each cultivar were stocked continuously with 3 steers, and additional grazers were added or removed as required to ensure similar grazing pressure in each treatment. Steers on Tanzania-I had a superior average daily gain (ADG) to those on Tobiatii and Coloniffo. However, the lack of difference in carrying capacity between Tanzdnin and Tobiatil pastures resulted in similar live-weight gain (LWG)/ha. The ADG and LWG/ ha of Coloniilo were significantly lower than the other …

Evaluation Of Brachiaria Decumbens And Brachiaria Brizantha Under Grazing, V.P B. Euclides, A H. Zimmer, M P. Oliveria

IGC Proceedings (1977-2023)

A 3-year grazing trial was conducted in Brazil, to relate changes in sward characteristics of B. decumbens and B. brizantha to animal live-weight gain (LWG). Three 1.5-ha paddocks of each grass species were stocked continuously with 3 steers, and additional grazers were added or removed as required to ensure similar grazing pressure in each treatment. Despite similar (P>0.85) annual average daily gains (ADO) of steers grazing both species, the ADO of steers grazing B. brizantha pasture was significantly (P<0.05) higher during the wet season, and significantly (P<0.05) lower in the dry period, when compared with those on B. decumbens. Annual LWG per area of both species were also similar (P>0.85). The best predictor of ADO was …

Effects Of Grain Supplement For Steers Grazing Stargrass Pastures On Subsequent Feedlot Gains And Carcass Characteristics, G.M.J Horton, W D. Pitman, E M. Hodges

IGC Proceedings (1977-2023)

Performance of steers (181 kg) grazing slargrass pastures was evaluated al 2 levels of grain supplementation in comparison with unsupplemenled cattle and with steers in drylot fed a high-roughage diet. Supplements during the 140-day winter period were fed at 1.0 (moderate) and 1.5% body weight (BW)lday (high), followed by 0.40 kg (moderate) and 0.5% BW/day (high) during the 98-day spring grazing period. Gains during a subsequent 100-dny, high-energy feeding period and resulting carcass characteristics were also compared. Gains during !he grazing period did not differ between !he 2 levels of supplement. Daily rate of gain of unsupplemented cattle (0.44 kg) …

Large-Scale Property Demonstrations Of The Effect Of Sexa Stylo And Phosphorus On Beef Cattle Growth In Central Queensland, Australia, C H. Middleton, K J. Murphy, G W. Blight, Vicki-Lee Hansen

IGC Proceedings (1977-2023)

Seca style (Stylosanthes scabra) was oversown into black speargrass (Heteropogon comortus)•dominant pasture after a burn at 2 sites in central Queensland, and the pasture was continuously grazed. At one site with <5 ppm bicarbonate-extractable soil P, Seca growth was poor and gave only a small animal growth response (18 kg/steer/year) over native pasture. With the addition of superphosphate (27 kg P/ha) the Seca-native grass produced an additional live-weight gain of 70 kg/ steer/year over the native pasture control. At a second site with 6-8 ppm available soil P, Seca grew well, and with a P supplement given to steers, live-weight gains were 40 kg/steer/year more than for P­supplemented animals grazing native pasture. Oversowing Seca into native pasture with P as fertiliser or a supplement can dramatically improve animal performance. The project was conducted on private properties and was aimed to focus producer attention on this technology, which is suited to large areas of northern Australia.

Improving Hill Agriculture Systems In Nepal: A Case Study, B N. Tiwari, J B. Abington

IGC Proceedings (1977-2023)

The Kingdom of Nepal is characterised by complex, diverse smallholder farming systems in which crops, livestock and forest resources are all interlinked. Traditional feeding practices throughout the hills are coming under severe pressure due to the high density of livestock. Consequently, acute shortages of forage are e, experienced, especially during the dry winter season. A case study is presented In which the integration of forage management into the whole farming system is practised, User groups are improving community grazing lands by the introduction of more productive herbage and fodder tree species. Fodder is sold to livestock farmers, animal management is …

Development Of Forage Systems For Dairying In Subtropical Australia, R J. Moss, K F. Lowe

IGC Proceedings (1977-2023)

The development of productive dairy farm systems integrating irrigated temperate pastures with rain-grown tropical pastures in subtropical Australia is described, Milk production increased from 2976-34211/cow (P<0,01) with increased temperate pasture allowance from 0. I to 0.2 ha/cow, and this increase was similar for nitrogen­fertilised ryegrass or clover-ryegrass mixtures, Temperate pastures provided cows with a high protein diet (20-30% crude protein}, enabling energy-rich grain and molasses concentrates to be efficiently used, Increasing supplementation to S kg grain/cow day increased milk yields to S109 I/lactation. Nitrogen fertilisation of perennial tropical grasses enabled higher stocking rates to be used and, together with the increases in production/cow, increased farm output from 464S I/ha to 7300 I/ha.

Use Of Blood Urea Nitrogen Concentration To Predict Response To Protein Or Energy Supplementation In Grazing Cattle, A C. Hammond, W E. Kunkle, D B. Bates, L E. Sollenberger

IGC Proceedings (1977-2023)

In healthy ruminants, blood urea nitrogen (BUN) concentrations are positively correlated with ruminal ammonia nitrogen concentrations and are indicative of the protein to energy ratio in the diet. Our objective was to determine whether BUN could predict the biological response (average daily gain, ADG) to protein or energy supplementation in free­grazing steers and heifers on tropical grass pastures, Change in ADO (-0.0S to 0.30 kg) due to protein supplementation was linearly related to BUN concentration (6,2-15,5 mg/di) in control cattle (P<0.05, slope= 0.023, r = 0.69, s = 0.07 kg). BUN concentrations of 9-12 mg/di were a transition range t��tow which ADG response to protein supplementation was greater (P«J.05) and above which ADG response was lesser (P<0, l 0) than the response within thls range. Change in ADO due to energy supplementation was not related to BUN in control cattle, but the range of BUN in our trials was limited to concentrations above 9 mg/di. Concentration of BUN may be a useful tool for predicting biological response to protein supplementation of grazing beef cattle.