How Does N Fertilization or Forage Legumes Affect Forage and Animal Production?

Livestock grazing in tropical climates is characterized by low productivity. Forage and animal production can be improved by applying nitrogen (N) fertiliser or using forage legumes. This 2.5-yr study assessed the canopy structure and productivity of beef cattle grazing either a mixed pasture of Brachiaria brizantha cv. Marandu (palisadegrass) and Arachis pintoi (forage peanut) cv. BRS Mandobi or a Marandu palisade grass monoculture with or without N fertilisation. The experiment was carried out in Southeast Brazil, where the canopy structure (herbage mass) and animal productivity (stocking rate and liveweight gain per ha) were compared for three types of pastures: 1) mixed pasture of Marandu palisade grass and forage peanut (GRASS+LEGUME); 2) a monoculture of Marandu palisadegrass fertilised with 150 kg N/ha/year (GRASS+N); and 3) monoculture of Marandu palisadegrass without N application (GRASS), under continuous stocking. A minimum of two Nellore heifers and additional put-and-takes were used to keep canopy height at 20-25 cm. A randomized complete block design was used with four replicates; seasons were considered repeated measurements over time. Herbage mass was greater in the GRASS+N pasture (P \u3c 0.001); however, in the last three seasons (Spring II, Summer III, and Fall III), there was no difference to GRASS+LEGUME pasture. In the GRASS+LEGUME pasture, there was an increase of legume mass (1.260 to 2.565 kg/ha) and botanical composition (23.6 to 39.1% of legume in forage mass) throughout the study. The stocking rate (P \u3c 0.001) and liveweight gain per ha (P \u3c 0.001) were greater in GRASS+N, without difference among GRASS+LEGUME and GRASS pastures in the first seven seasons. In the last three seasons, with an increase of legume proportion, stocking rate and liveweight were intermediate for GRASS+LEGUME pasture. Legume increased herbage mass and animal productivity in the long term. Immediate responses were achieved with N fertilization

Anharmonic transitions in nearly dry L-cysteine I

Two special dynamical transitions of universal character have been recently observed in macromolecules at $T_{D}\sim 180 - 220$ K and $T^{*}\sim 100$ K. Despite their relevance, a complete understanding of the nature of these transitions and their consequences for the bio-activity of the macromolecule is still lacking. Our results and analysis concerning the temperature dependence of structural, vibrational and thermodynamical properties of the orthorhombic polymorph of the amino acid L-cysteine (at a hydration level of 3.5%) indicated that the two referred temperatures define the triggering of very simple and specific events that govern all the biochemical interactions of the biomolecule: activation of rigid rotors ($T<T^{*}$), phonon-phonon interactions with phonons of water dimer ($T^{*}<T<T_{D}$), and water rotational barriers surpassing ($T>T_{D}$).Comment: 4 pages, 4 figures, submitted to Physical Review Letter

Sodium alginate/polycaprolactone co-axial wet-spun microfibers modified with N-carboxymethyl chitosan and the peptide AAPV for Staphylococcus aureus and human neutrophil elastase inhibition in potential chronic wound scenarios

In chronic wound (CW) scenarios, Staphylococcus aureus-induced infections are very prevalent. This leads to abnormal inflammatory processes, in which proteolytic enzymes, such as human neutrophil elastase (HNE), become highly expressed. Alanine-Alanine-Proline-Valine (AAPV) is an antimicrobial tetrapeptide capable of suppressing the HNE activity, restoring its expression to standard rates. Here, we proposed the incorporation of the peptide AAPV within an innovative co-axial drug delivery system, in which the peptide liberation was controlled by N-carboxymethyl chitosan (NCMC) solubilization, a pH-sensitive antimicrobial polymer effective against Staphylococcus aureus. The microfibers' core was composed of polycaprolactone (PCL), a mechanically resilient polymer, and AAPV, while the shell was made of the highly hydrated and absorbent sodium alginate (SA) and NCMC, responsive to neutral-basic pH (characteristic of CW). NCMC was loaded at twice its minimum bactericidal concentration (6.144 mg/mL) against S. aureus, while AAPV was loaded at its maximum inhibitory concentration against HNE (50 μg/mL), and the production of fibers with a core-shell structure, in which all components could be detected (directly or indirectly), was confirmed. Core-shell fibers were characterized as flexible and mechanically resilient, and structurally stable after 28-days of immersion in physiological-like environments. Time-kill kinetics evaluations revealed the effective action of NCMC against S. aureus, while elastase inhibitory activity examinations proved the ability of AAPV to reduce HNE levels. Cell biology testing confirmed the safety of the engineered fiber system for human tissue contact, with fibroblast-like cells and human keratinocytes maintaining their morphology while in contact with the produced fibers. Data confirmed the engineered drug delivery platform as potentially effective for applications in CW care.Authors acknowledge the Portuguese Foundation for Science and Technology (FCT), FEDER funds by means of Portugal 2020 Competitive Factors Operational Program (POCI) and the Portuguese Government (OE) for funding the project PEPTEX with reference PTDC/CTMTEX/28074/2017 (POCI-01-0145-FEDER-028074). Authors also acknowledge project UIDP/00264/2020 of 2C2T and UID/QUI/00686/2020 of CQ, funded by national funds through FCT/MCTES. C.S.M. and H.P.F. also acknowledge FCT for PhD funding via scholarship 2020.08547.BD and for auxiliary researcher contract via 2021.02720.CEEIND, respectively

Desempenho de novilhas em pastagens formadas pelos capins tifton 85, xaraés e mombaça, sob lotação rotativa.

O experimento foi conduzido na Estação de Zootecnia do Extremo Sul (Essul), pertencente a Comissão Executiva do Plano da Lavoura Cacaueira (CEPLAC), localizada no município de Itabela - Bahia - Brasil. Com o objetivo de avaliar o ganho de peso individual e por unidade de área de novilhas girolandas manejadas sob lotação rotativa em três pastagens fertilizadas com nitrogênio e irrigadas. As pastagens foram de Tifton 85, com 18 piquetes de 667 m2 , Xaraés e Mombaça, ambos com 28 piquetes de 429 m2 . O delineamento experimental foi em blocos casualizados com medidas repetidas no tempo ou por ciclo de pastejo. Com base em 224 dias de avaliações, não foram observadas diferenças significativas quanto ao ganho de peso por animal, por área e nem na lotação animal, ficando os ganhos por unidade de área entre 2,59 e 3,52 kg ha -1 dia-1 e a lotação entre 5,06 e 5,61 UA ha-1

Stoloniferous Forage Legumes for Sustainable Mixed Pastures in the Tropics

Brazil has over 80 million ha of tropical pastures formed with species of Brachiaria (syn. Urochloa), mostly grazed by beef cattle and with low fertilizer inputs, especially nitrogen. Recent investigations by our team show that stoloniferous legumes such as forage peanut (Arachis pintoi) and Desmodium ovalifolium are able to persist in mixed swards with Brachiaria brizantha (cv. Marandu) if grazing height is regulated (maximum 30 cm) so that radiation can reach the soil surface allowing stolons to take root. These legumes can persist in mixed pastures and produce milk or animal weight gains similar to the application of 120 to 150 kg N/ha/yr. In studies at the CEPLAC field station south Bahia State (16°39´S, 39°30´ W), N2O emissions from urine of dairy cattle were 0.47 and 0.76 kg N-N2O/ha/yr for a mixed forage peanut/Marandu pasture and Marandu monoculture + 120 kg N fertilizer ha/yr, respectively, equivalent to emission factors (EF) of 0.81 and 2.09%. N2O emissions from the N fertilizer were 2.70 and 0.24 kg N-N2O/ha (EFs of 4.10 and 0.40 %) for the two applications, respectively. N2O emissions from urine of beef cattle were 0.314 and 0.267 kg N-N2O/ha/yr for a mixed Desmodium ovalifolium/Marandu pasture and Marandu monoculture + 150 kg N fertilizer ha/yr, respectively, equivalent to EFs of 0.45 and 0.40 %. Annual N2O emissions from 3 x 50 kg N fertilizer were 0.30 kg/ha/yr. Preliminary results indicate that enteric methane emissions from cattle grazing a mixed forage peanut/Marandu pasture were 9 % lower per kg weight gain than those on an N-fertilized Marandu monoculture. Considering the total elimination of the fossil CO2 emissions associated with manufacture and application of N fertilizer, the substitution of 150 kg N by the mixed grass legume pastures represents a decrease in GHG emission intensity of over 20 %

Photoabsorption and photoionization studies of the amino acid proline in the VUV region

Ionic fragmentation of the sublimated amino acid DL-proline has been studied using time-of-flight mass spectrometry and synchrotron radiation. Total ion yield and mass spectra were recorded in the 13 to 21.6 eV energy range. Partial ion yields have been calculated for the produced fragments and the results analyzed in a comparative way. Mass spectrum of proline previously obtained at 21.21 eV using photons from a discharge lamp (He I), was used as reference in the comparison to the synchrotron radiation based spectra. The loss of the COOH fragment represents the most probable dissociation pathway following the photoionization of DL-proline in the valence region. These are the first results of total and partial ion yields spectra for this molecule in its gas phase in the valence region using time-of-flight spectrometry

Adaptabilidade e estabilidade de híbridos de sorgo biomassa semeados em três locais na safra 2021/2022.

O objetivo desse trabalho foi avaliar a adaptabilidade e estabilidade para a produtividade (t.ha-1) de 25 híbridos de sorgo destinadas à produção de biomassa.Evento híbrido

Avaliação da produção de insumos oriundos do sorgo sacarino usados na geração de bioenergia.

Evento híbrido