Physical Sciences and Mathematics Commons^™

Dry Matter Production And Nutritive Value Of Alfalfa (Medicago Sativa L.) And Orchardgrass (Dactylis Glomerata L.) Under Different Light Regimes, A. C. Varella, P. L. Peri, R. J. Lucas, D. J. Moot, D. L. Mcneil

IGC Proceedings (1993-2023)

Spring and summer alfalfa dry matter and nitrogen production rates were greater than orchardgrass in open pasture and under three shade levels. Ten years old Pinus radiata allowed 60% light transmissivity. The addition of artificial shade resulted in 45% and 25% transmissivity. Orchardgrass pastures were nitrogen deficient and water stressed. In contrast, alfalfa was not stressed and it was more light responsive than orchardgrass. Differences in nutritive value were relatively small between species and between light regimes. Sheep liveweight gain on alfalfa was greater than on orchardgrass. Orchardgrass demonstrated shade tolerance, but alfalfa was more productive even at 25% transmissivity. …

Different Methods Of Artificial Shade For Agro-Silvipastoral Research, A. C. Varella, D. J. Moot, R. J. Lucas, D. L. Mcneil, P. L. Peri, K. M. Pollock

IGC Proceedings (1993-2023)

Artificial shading sources are used to simulate silvipastoral light environments and study the effect of shade on pasture. Different sources of shade may not imitate normal forest light environment. An experiment was conducted to examine the light environment and effect on pasture yield components of two artificial shading materials. Alfalfa (Medicago sativa L.) pasture was submitted to three light regimes: full sunlight (100% transmissivity); black shade cloth (40%) and wooden slats (45%).

The pattern of light exposure for plants differed under slats and shade cloth, but light intensity and quality were similar. Alfalfa dry matter (DM) yield and leaf …

Modeling Of Groundwater Potential Using Cloud Computing Platform: A Case Study From Nineveh Plain, Northern Iraq, Ali Za. Al-Ozeer, Alaa M. Al-Abadi, Tariq Abed Hussain, Alan E. Fryar, Biswajeet Pradhan, Abdullah Alamri, Khairul Nizam Abdul Maulud

Earth and Environmental Sciences Faculty Publications

Knowledge of the groundwater potential, especially in an arid region, can play a major role in planning the sustainable management of groundwater resources. In this study, nine machine learning (ML) algorithms—namely, Artificial Neural Network (ANN), Decision Jungle (DJ), Averaged Perceptron (AP), Bayes Point Machine (BPM), Decision Forest (DF), Locally-Deep Support Vector Machine (LD-SVM), Boosted Decision Tree (BDT), Logistic Regression (LG), and Support Vector Machine (SVM)—were run on the Microsoft Azure cloud computing platform to model the groundwater potential. We investigated the relationship between 512 operating boreholes with a specified specific capacity and 14 groundwater-influencing occurrence factors. The unconfined aquifer in …

Competition For Light In A Leucaena Leucocephala / Chloris Gayana Silvopastoral System, N. F. G. Rethman, J. P. Lindeque

IGC Proceedings (1993-2023)

The spatial variation in the vigour of Leucaena (Leucaena leucocephala cv. Cunningham) trees growing together with Rhodesgrass (Chloris gayana cv. Katambora) in an alley cropping system made it possible to assess the competitive effect for light. The height and especially lateral development of trees had a strong influence on light interception by the canopy, with radiation in the intercrop area being 49% lower where the trees were more vigorous. There was a corresponding (43%) decrease in grass production. These findings indicate that future studies should also include aspects such as espacement of trees, pruning of trees in the …

Optimizing Yield And Quality Of Orchardgrass Pasture In Temperate Silvipastoral Systems, P. L. Peri, R. J. Lucas, D. J. Moot, A. C. Varella, D. L. Mcneil

IGC Proceedings (1993-2023)

The objective of this study was to provide grazing management recommendations for a silvipastoral system by determining the effects of shade and nitrogen (N) on the pattern of dry matter accumulation and nutritive value of orchardgrass (Dactylis glomerata) in a subhumid temperate environment. Orchardgrass in open pasture (100% transmittance) and under 10 year old Pinus radiata tree shade (60% transmittance) at 200 stems/ha was used as the main plot and nitrogen (0 and 300 kg N/ha as synthetic urine) was the subplot factor. Dry matter (DM) production of orchardgrass in the first 60-day spring rotation was similar in …

Herbage Characteristics As Affected By The Canopies Of Dominant Trees In A Savanna Of Southern Mozambique, James P. Muir, A. Alage, Inacio C. Maposse

IGC Proceedings (1993-2023)

This study surveyed the species composition, forage yield and forage nitrogen concentration of the herbaceous layer 50, 100 and 200% of the canopy radius from the trunks of many-stemmed false thorn, knob thorn, scented thorn and marula trees in a southern Mozambican savanna. Tree species did not affect herbaceous DM yield or species diversity. Neither direction nor distance from the tree trunk affected DM or specific diversity. Crude protein percentages were 15% higher for legumes and 9% higher for grasses at 50% canopy than at 200% canopy. Grasses under the marulas, the only non-legume tree in the study, had 18% …

Selecting New Brachiaria For Brazilian Pastures, Cacilda B. Do Valle, Valéria P. B. Euclides, Manuel C. M. Macedo, José R. Valério, S. Calixto

IGC Proceedings (1993-2023)

Brazilian beef production relies heavily on cultivated pastures, of which about 80% are planted mainly to two Brachiaria cultivars. The narrowness of diversity associated with reproduction by apomixis of most plants in this genus prompted an intense search for new cultivars amongst recently collected and introduced ecotypes from Africa. This paper reports results for a three-year evaluation of 21 pre-selected ecotypes in two typical Cerrado ecosystems. Plots, replicated four times, were seeded in rows and cut every 6 weeks during the rainy season followed by a cut in the middle and one at the end of the dry season. Significant …

Aberrant Crosstalk Between Insulin Signaling And Mtor In Young Down Syndrome Individuals Revealed By Neuronal-Derived Extracellular Vesicles, Marzia Perluigi, Anna Picca, Elita Montanari, Riccardo Calvani, Federico Marini, Roberto Matassa, Antonella Tramutola, Alberto Villani, Giuseppe Familiari, Fabio Di Domenico, D. Allan Butterfield, Kenneth J. Oh, Emanuele Marzetti, Diletta Valentini, Eugenio Barone

Chemistry Faculty Publications

INTRODUCTION: Intellectual disability, accelerated aging, and early-onset Alzheimer-like neurodegeneration are key brain pathological features of Down syndrome (DS). Although growing research aims at the identification of molecular pathways underlying the aging trajectory of DS population, data on infants and adolescents with DS are missing.

METHODS: Neuronal-derived extracellular vesicles (nEVs) were isolated form healthy donors (HDs, n = 17) and DS children (n = 18) from 2 to 17 years of age and nEV content was interrogated for markers of insulin/mTOR pathways.

RESULTS: nEVs isolated from DS children were characterized by a significant increase in pIRS1^Ser636, a marker of …

Supplmentary Feeding And Management Strategies To Overcome Drought Situations On Three High Producing New Zealand Seasonal Dairy Farms, S. H. Benson, P. N. P. Matthews

IGC Proceedings (1993-2023)

This paper investigates the outcomes of the management strategies to overcome dry summer conditions on three New Zealand seasonal supply dairy farms where the summer management philosophy is towards production rather than survival aimed at giving the farmer control rather than accepting the unreliable production outcomes often achieved. Actual data collected from the case farms as part of a large on-farm monitoring programme was used to model the dry 1998/99 season. This was compared with simulated models for an average season to estimate milksolids responses (g milksolids (MS)/kg DM) and net returns (cents/kg DM) to the additional feeds used. In …

A Simulation Model To Evaluate Supplementation Of Tropical Forage Diets For Dairy Cows, A. G. Assis, O. F. Campos, J. Dijkstra, J. France

IGC Proceedings (1993-2023)

A dynamic model of digestion kinetics has been built to evaluate dairy cattle diets based on tropical feeds and to estimate the potential of tropical forages for milk production associated with available supplements. Results of simulation were very consistent showing that grazed elephant grass alone can supply nutrients for cow maintenance and yield of 7.10 kg milk/day. Nevertheless, to produce 25 kg/day on grazed elephant grass, a dairy cow would need to be supplemented with 5.85 kg/day of a mixture of cottonseed meal (50%) plus ground maize (50%), while on maize silage it would be necessary 4.15 kg of the …

Performance Of Beef Heifers Of Various Genetic Groups, Supplemented Or Not, In Coastcross Pastures, Armando De A. Rodrigues, Geraldo M. Da Cruz, Rogério T. Barbosa, Maurício M. De Alencar, Luciano De A. Corrêa, Gilson P. De Oliveira

IGC Proceedings (1993-2023)

The objective of this study was to determine whether the performance of beef heifers of different genetic groups was affected by breed x nutritional environment interactions. Sixty four weaned heifers, 16 per genetic group: ½ Angus + ½ Nellore (AN), ½ Canchim + ½ Nellore (CN), ½ Simmental + ½ Nellore (SN) and pure Nellore (NE), were used with or without 3.0 kg of concentrate.animal^-1 .day^-1 in a fertilized coastcross pasture under rotational grazing system. There were effects of genetic group and supplementation (P< 0.05) on the weight and age at first estrus, but there was no interaction between them. In a rotational grazing system with 4000 kg of available dry matter per hectare with 13% of crude protein, the crossbred AN, supplemented or not, was more precocious (111 days) than Nellore heifers, showing the first estrus at 356 days of age and 324 kg of live weight.

Animal Performance On Brachiaria Brizantha Alone Or Supplemented With Concentrate Or Protein Bank Of Leucaena Leucocephala, Antonio João Lourenço, Paulo Roberto Leme, Marcelo De Queiroz Manella

IGC Proceedings (1993-2023)

The experiment was carried out at the Instituto Zootecnia, Nova Odessa, SP, Brasil, from June/1998 to March/2000 (634 days), and the liveweight gains of Nelore steers was evaluated, per animal and per area, on Brachiaria brizantha alone (T₁), B. brizantha + Leucaena leucocephala (T₂), B. brizantha + supplemental feeding during the dry season (T₃) and B. brizantha + supplemental feeding during the dry and rainy season (T₄). The experimental design was a randomized block, with four replications each one composed by three paddocks rotationally grazed by Nelore steers. Mean weight gain per …

Urine Calcium But Not Plasma Calcium Or Urine Hydroxyproline Is Increased By A Systemic Acidosis In The Dairy Cow, J. R. Roche, Dawn E. Dalley, F. O’Mara, E. S. Kolver

IGC Proceedings (1993-2023)

Eight non-lactating, pregnant Holstein-Friesian cows were allocated to two treatments and individually offered diets differing in dietary cation-anion difference. Decreasing the dietary cation-anion difference reduced the urine pH within hours of anionic salt supplementation. Plasma calcium concentration was unaffected by dietary cation-anion difference but urine calcium concentration was significantly increased within 10 days of including anionic salts in the diet. Faecal calcium concentration was significantly reduced, indicating increased calcium absorption. Dietary calcium concentration or dietary cationanion difference did not significantly affect urinary hydroxyproline.

Dry Matter Intake Of Periparturient Cows On A Fresh Pasture/Pasture-Hay Diet, J. R. Roche, Dawn E. Dalley, F. O’Mara, E. S. Kolver

IGC Proceedings (1993-2023)

Reports of the depression in dry matter intake in the periparturient period have been inconsistent and little dry matter intake data is available for an all-forage diet prior to calving. Data to examine intake depression prior to calving was obtained from two experiments. In experiment 1, sixteen non-lactating, periparturient cows ate 1.3% of pre-calving body weight of grass-hay and freshly cut grass for two weeks pre-calving (restricted). Experiment 2 comprised thiry-six cows that ate 1.6% of pre-calving body weight of grass-hay and freshly cut grass for the final two weeks of pregnancy (ad libitum). Individual dry matter intakes …

Effectt Of Supplements On Forage Degradability Of Brachiaria Brizantha Cv. Marandu Grazed By Steers, J. R. A. Pereira, Ricardo A. Reis, L. R. De A. Rodrigues, D. Freitas

IGC Proceedings (1993-2023)

The supplementation effect was evaluated using crossbred rumen-fistulated steers maintained in a Brachiaria brizantha cv. marandu pasture. The animals received energy supplementation (corn-COR); low degradability protein supplementation (corn gluten-GLU); and high degradability protein supplementation (soybean-SBM) at two levels N1 (± 0.5 kg/an/day) and N2 (± 1.5 kg/an/day); or no supplementation (Control). The factorial (3x2), plus the control, was studied according to complete randomized block design with three replications. The supplementation did not affect (P> 0.05) the potential degradability (POD), the effective degradability (EFD), and the degradation rates (DR) of the forage (extrusa). The GLU supplementation provided higher (P< 0.05) EFD of the NIDN fraction than the SBM, and both did not differ (P> 0.05) of …

Use Of Supplements For Increasing Performances Of Suckling Martinik Ewes When Fed Tropical Forages, E. O. Jimenez, G. Alexandre, H. Archimède, P. Despois, M. Jean-Bart, C. Jacquet

IGC Proceedings (1993-2023)

Experiments have been carried out to determine the effects of supplementation upon milk production and growing performances with hair sheep Martinik ewes weighing 48 ± 4 kg liveweight (LW). In a first trial, 6 single bearing ewes (group GS) were offered individually a daily 0.5 kg of commercial pellets. They were compared to the control group (GN; 6 ewes) with no supplement during 10 weeks of lactation. Basal diet was chopped Digitaria decumbens grass ad libitum. In a second trial, level of supplementation was adapted to the ewes’ litter size: 6 twins bearing ewes (TW) and 6 single (SI). …

Performance Of Dairy Goats To Alfalfa Silage Based Diets Supplemented With Different Sources Of Carbohydrates, J. L. Danelón, P. Allocati, M. Wawrzkiewicz, S. Bedogne, E. Ceballos, M. D’Alessio, L. Barletta, C. Colatto, D. Victoria

IGC Proceedings (1993-2023)

Lactating Saanen dairy goats fed alfalfa silage (AS) based diets in four 4x4 Latin Square designed experiment were studied for the effects of supplementation of three different type of carbohydrates (wheat grain, (W); sorghum grain, (SG) and dry citrus pulp, (DCP)) on milk yield, composition and chewing activities. Sixteen does (45± 10 DIM and 2.016 kg ± 0.48 4% FCM) housed indoors in individual pens in a four 4x4 experiment were fed four diets 1) AS (33.9%DM, 19.9%CP, 44.01%NDF); 2) ASW (52.4%DM, 19.8%CP, 33.7%NDF); 3) ASSG (50.9%DM, 17.9%CP, 37%NDF), 4) ASDCP (52.5%DM, 16.12%CP, 39.1%NDF) with forage-to-concentrate ratios of 100:0 or …

Mineral Concentration Of Herbage From Three Paulownia Species Used For Goat Browse, J-M. Luginbuhl, J. P. Mueller, B. A. Bergmann

IGC Proceedings (1993-2023)

Goats naturally prefer a high proportion of browse in their diets. Therefore, research was initiated to investigate various silvo-pastoral production systems. In May 1997, six Paulownia treatments were planted in a randomized complete block experiment with six replications. Trees were between 6 and 12 cm in height at planting. Treatments included: P. fortunei seedlings, P. tomentosa seedlings, P. elongata seedlings, and three P. elongata clones. Each 4-m wide plot contained a single row of 12 trees with an intra-row spacing of 1 m. Leaf samples were analyzed from all six replications to determine mineral concentration in October 1997, and June …

Integrating Pastures Into The Traditional Slash-And-Burn Cycle In Northeastern Pará, Brazil, S. Hohnwald, B. Rischkowsky, R. Schultze-Kraft, J. M. King, A. P. Camarão

IGC Proceedings (1993-2023)

A project to test possibilities to integrate pastures into the traditional slash-and-burn cycle of small farmers in the Bragantina region in northeastern Pará, Brazil, is presented. Whereas in practice the traditional grass-only pasture is managed separately from the crop/fallow cycle, two options for integration are tested: a Brachiaria humidicola pasture enriched with two bushy and one herbaceous legume, Cratylia argentea, Chamaecrista rotundifolia and Arachis pintoi, and a B. humidicola pasture allowing a controlled regrowth of secondary vegetation ("Capoeira"). The regeneration performance of these pastures for a subsequent cropping period is compared with plots of undisturbed regrowth of Capoeira …

Relationship Between Canopy Closure And Pasture Production In Deciduous Tree Based Temperate Silvopastoral Systems, N. R. Devkota, A. J. Wall, Peter D. Kemp, J. Hodgson

IGC Proceedings (1993-2023)

Experiments were carried out in New Zealand with 11 year-old alder (Alnus chordata) on lowland pasture, and with 30+ year-old poplar (Populus spp) on hill pasture. Alder tree shade decreased (P< 0.001) tiller density and total herbage harvested, with the highest tiller density at the lowest shade level of 41% canopy closure (DifN 0.59). Net herbage accumulation (NHA) directly under a poplar canopy was 35% of the NHA of open pasture, but NHA in canopy gaps increased with gap size. These results suggested that keeping canopy closure percentage in the 40-50% range for a deciduous tree silvopastoral system, would maintain pasture production and tiller density at approximately two-thirds of that of unshaded pasture.

Annual Dry Matter And Nutrient Yields In A Dichanthium Sward With Or Without Gliricidia Shrubs, P. Cruz

IGC Proceedings (1993-2023)

The aim of this work was to compare the annual biomass production and nutrient removal of a Dichanthium aristatum pasture with those of a pasture of the same species associated with a leguminous tree, Gliricidia sepium. Measurements were made over twelve months between April 1993 and April 1994. Sampling was done with the same defoliation frequency as an intensive cut-and-carry system: every 4 and 10 weeks for the grassland and tree layers respectively. There was no significant difference between the yield of the pure grass (21.6 ± 2.0 t ha^-1) and that of the grass with trees …

Accumulation Of Mutated Maize Zeins In Transgenic Forage Legumes, Sergio Arcioni, A. Alpini, M. Bellucci

IGC Proceedings (1993-2023)

Accumulation of zeins, the endosperm storage proteins of maize, in a heterologous plant expression system was attempted. Plants of birdsfoot trefoil (Lotus corniculatus) and alfalfa (Medicago sativa) were transformed by Agrobacterium with binary vectors harboring genes that code for γ-zein and β-zein, two proteins rich in sulphur amino acids. Adding the ER retention signal KDEL to the C-terminal domain modified zein polypeptides. Our long-term goal was to improve birdsfoot trefoil and alfalfa forage quality. Significant levels of γ- zein:KDEL and β-zein:KDEL were detected in primary transformants of birdsfoot trefoil. Moreover, alfalfa plants expressing γ-zein:KDEL in the …

Effect Of The Mixed Rates Of Endophyte-Free And -Infected Seed On The Dry Matter Yield And Forage Quality Of Tall Fescue, J. K. Lee, S. H. Yoon, S. Seo, D. A. Kim, Y. W. Rim, G. J. Park, S. K. Lee

IGC Proceedings (1993-2023)

This study was carried out to investigate the effect of the mixed rates of endophyte-free and infected seed on the dry matter yield and forage quality of tall fescue in Korea. In experiment, mixed ratios of endophyte-infected and -free seed were compared under the fourth cutting. Dry matter yield and forage quality of tall fescue were not influenced by mixed rates. The weed contents of botanical composition were slightly increased with high ratios of endophyte-free seed. The results demonstrated that endophyte-free tall fescue did not seem to be greatly weak under bad conditions.

Impact Of Management On Endophyte Free And Endophyte Infected Tall Fescue Cultivars In Ohio, C. D. Penrose, Reuben M. Sulc, J. S. Mccutcheon

IGC Proceedings (1993-2023)

Ten cultivars of tall fescue (Festuca arundinacea, Schreb.) and one cultivar of orchardgrass (Dactylis glomerata L.) were part of a study to determine changes in endophyte levels of fescue under two different styles of forage management: intensive and extensive. Included in the study were two endophyte infected-cultivars of tall fescue to compare interactions with endophyte free and infected cultivars. After three years, the results demonstrate that under high levels of management and non-endophyte infected crops prior to seeding, introduction of the endophyte can be reduced or delayed. Under lower levels of management and a smother crop into …

Grazing Endophyte Infested Tall Fescue And Changes In Bovine Blood Components And Gain, H. A. Fribourg, J. C. Waller, A. E. Schultze, B. W. Rohrbach, J. W. Oliver

IGC Proceedings (1993-2023)

Tall fescue (Festuca arundinacea) is utilized on more than 15 million ha of pasture in the eastern USA and over 80% of the plants in this area are infested with the endophyte Neotyphodium coenophialum. Tall fescue toxicosis results from consumption of the infested (E+) grass host and is an important problem that causes considerable economic loss to producers. However, the agronomic attributes of tall fescue make it an attractive forage because of its ability to withstand cool temperatures, drought, poor soil conditions and intensive defoliation. There is need to understand mechanisms of animal physiology that are affected …

Premade Nanoparticle Films For The Synthesis Of Vertically Aligned Carbon Nanotubes, Abdul Hoque, Ahamed Ullah, Beth S. Guiton, Noe T. Alvarez

Chemistry Faculty Publications

Carbon nanotubes (CNTs) offer unique properties that have the potential to address multiple issues in industry and material sciences. Although many synthesis methods have been developed, it remains difficult to control CNT characteristics. Here, with the goal of achieving such control, we report a bottom-up process for CNT synthesis in which monolayers of premade aluminum oxide (Al₂O₃) and iron oxide (Fe₃O₄) nanoparticles were anchored on a flat silicon oxide (SiO₂) substrate. The nanoparticle dispersion and monolayer assembly of the oleic-acid-stabilized Al₂O₃ nanoparticles were achieved using 11-phosphonoundecanoic acid …

Phylogenetic Grouping By Pcr Analyses Of Sinorhizobium Meliloti Strains Isolated From Eutrophic Soil, W. S. Oliveira, P. P. A. Oliveira, C. M. Bellato, F. R. S. Duarte, S. M. Tsai

IGC Proceedings (1993-2023)

This study evaluated the ability of Sinorhizobium meliloti strains (SEMIA-116, SEMIA- 134 and SEMIA-135) to persist in eutrophic soils after three complete growing cycles of alfalfa. PCR fingerprinting using primers for the nifH, Eric, Rep, RP genes and P25 RAPD-PCR performed the phylogenetic grouping of the three commercial strains and 39 field isolates. These analyzes were sufficiently sensitive to discriminate and group the strains and isolate. Our preliminary studies were based upon Eric primers and RP01 RAPD-PCR.

Achievements And Perspectives In The Breeding Of Temperate Grasses And Legumes, Kenneth H. Quesenberry, M. D. Casler

IGC Proceedings (1993-2023)

This paper will focus on a historical perspective on cool season forage production, plant breeding methods for cool season forages, major cool season forage selection criteria, some examples of significant achievements, and a future perspective. Topics similar to ours have been discussed at recent previous meeting of this Congress (Humphreys, 1997; Van Wijk et al., 1993); however, we will strive to avoid “plowing the same ground twice”. In an attempt to prevent duplication of content with other sections of this Congress, only limited attention will be given to genetic resource acquisition and conservation. Additionally, alfalfa (Medicago sativa L.), one …

Achievements And Perspectives In The Breeding Of Tropical Grasses And Legumes, John W. Miles

IGC Proceedings (1993-2023)

Pasture and forage plant breeding is complicated by the perennial nature of the plants, the diversity of environments in which improved cultivars will be used, and the complex criteria of merit involved, criteria that necessarily include some measure of impact on the efficiency of animal production. While pasture plant breeding in the temperate zone is a demonstrably productive activity, the record of success for the tropical species -- "success" measured by release and adoption of bred cultivars -- is less convincing, in spite of four decades of activity in numerous public sector breeding programs and a large published literature. The …

Tropical Forage Genetic Resources -- Will Any Be Left For Future Generations?, B. L. Maass, B. C. Pengelly

IGC Proceedings (1993-2023)

After very active years of pasture and forage research at major institutes, interest in tropical forage genetic resources has drastically declined. Apparently, the early phases of collecting and evaluation were much more valued than conserving and keeping the germplasm available for future generations. Accumulated data are not easily accessible and, therefore, the knowledge of tropical forage genetic resources is progressively being lost. This worldwide decrease in activity and loss of knowledge is due to declining resources. It is suggested that a global database on tropical forage genetic resources should be established and also that finances be made available to at …