DSpace Coleção: Artigo em periódico indexado (CPAC)

Performance of beef cattle under grazing as affected by Urochloa decumbens cultivars.

Thu, 01 Jan 2026 00:00:00 GMT

Título: Performance of beef cattle under grazing as affected by Urochloa decumbens cultivars. Autoria: BRAGA, G. J.; RAMOS, A. K. B.; CARVALHO, M. A.; KARIA, C. T.; BARRIOS, S. C. L. Conteúdo: Testing animal performance under grazing is fundamental to determine the potential of recently released, high-yielding Urochloa decumbens hybrids. The objective was to evaluate the weight gain of young bulls grazing on pastures of U. decumbens cultivars Basilisk, BRS Carinás, and BRS Poraitê, as well as to assess the nutritive value and plant-part composition of the forage. The experiment was conducted over 2 years in a clay soil, using a randomized block design with three replicates. Pastures were managed under continuous stocking with a variable stocking rate (SR), aiming to maintain a canopy height of 25 cm. In contrast to the leaf blade and stem, the amount of dead material increased from the rainy to the early dry season, with Basilisk showing a greater mean value (1314 kg DM/ha), followed by Poraitê (1150 kg DM/ha) and Carinás (1127 kg DM/ha) (p < 0.10). Carinás and Poraitê had slightly greater crude protein (CP) (114 g/kg) compared to Basilisk (105 g/kg), particularly during the first year. Animals grazing Carinás had greater average daily gain (ADG) (0.62 kg LW) compared to Poraitê (0.54 kg LW), and similar performance to Basilisk (0.59 kg LW). In terms of live weight gain per area (GA), Carinás outperformed the other cultivars, reaching 406 kg LW/ha/year, compared to 359 and 358 kg LW/ha/year for Basilisk and Poraitê, respectively, due to the greater ADG and the increased SR observed during the rainy season. Carinás and Poraitê have potential for promoting cattle growth, owing to their comparable forage quality and plant-part composition to Basilisk. However, the superior live weight gain per area observed for Carinás demonstrates its greater carrying capacity, without compromising individual animal performance.

Análise do índice da qualidade da paisagem do médio rio Cristalino, município de Cocalinho, Mato Grosso, Brasil.

Thu, 01 Jan 2026 00:00:00 GMT

Título: Análise do índice da qualidade da paisagem do médio rio Cristalino, município de Cocalinho, Mato Grosso, Brasil. Autoria: VILELA, M. de F.; MAGALHÃES, I. A. L.; MELO, A. C. A. de; BETTIOL, G. M.; ALBUQUERQUE, L. B. de; SANO, E. E. Conteúdo: O objetivo do estudo foi determinar o Índice de Qualidade da Paisagem (IQP) na bacia hidrográfica do médio rio Cristalino no município de Cocalinho, estado de Mato Grosso, Brasil, por meio de ferramentas de sistema de informações geográficas e técnicas de sensoriamento remoto. O estudo foi baseado no mapeamento de uso e cobertura da terra da bacia hidrográfica obtido por meio da fotointerpretação do mosaico mensal do satélite PlanetScope adquirido em setembro de 2022, disponível na plataforma Google Earth Engine. O passivo ambiental nas áreas de preservação permanente (APPs) foi estimado calculando-se as áreas de intervenção antrópica ao longo dessas áreas de preservação. Para análise da qualidade da paisagem, foram considerados os dados de vegetação nativa, fragmentação, degradação e passivo ambiental ao longo das APPs, categorizados segundo a escala de Braun-Blanquet. A área do passivo ambiental em APPs hídricas foi mensurada em 4.061 ha, o que representa um passivo de 29%. O IQP calculado foi de 3,75, considerado como de média a alta qualidade ambiental.

Climate change-driven aridity threatens vegetation vigor in the Brazilian semiarid region.

Thu, 01 Jan 2026 00:00:00 GMT

Título: Climate change-driven aridity threatens vegetation vigor in the Brazilian semiarid region. Autoria: SILVA, L. A. P. da; SOUZA, C. M. P. de; SANO, E. E.; PARREIRAS, T. C.; BOLFE, E. L.; SOUZA, B. I.; SOUZA, R. S.; LEITE, M. E.; ESPÍRITO-SANTO, M. M.; CHAGAS-REIS, C. C. das; SILVA, I. C. da; SENA-SOUZA, J. P.; SILVA, C. R. da Conteúdo: Aridification driven by future climate change is expected to significantly change vegetation vigor in global drylands. However, its impacts on the Brazilian semiarid region, one of the world most populous and biodiverse drylands, remains poorly understood. In this study, we employed the Random Forest (RF) model trained with historical edaphoclimatic data to predict changes in vegetation vigor under future climatic scenarios (2061–2080), defined by the Shared Socioeconomic Pathways (SSPs), including an optimistic scenario (SSP1-2.6) and a pessimistic scenario (SSP5-8.5). Model performance was satisfactorily, with the Holdout Test exhibiting R2 = 0.93, RMSE = 0.02, and MAE = 0.02. Seasonal forests are projected to face a decline in greenness (SSP1-2.6 = down to −3.23% and SSP5-8.5 = −7.23%). Similarly, ombrophilous forests are expected to lose between -0.72% and -6.04% in vegetative vigor in the optimistic and pessimistic scenarios, respectively. Despite its natural adaptation to water deficit conditions, the Caatinga biome is also expected to show a significant decrease in vegetation vigor (−2.90% to −3.40%). Ecotonal zones are also projected to lose vegetative vigor (−2.08% to −4.31%). In contrast, savanna formations are expected to undergo a greening trend (+0.78%). Our results provide valuable insights for environmental planning and management, highlighting the most vulnerable vegetation types to future climate-induced aridification.

Investigation of the potential of commercial and wild Passiflora seed species as stilbenes sources.

Wed, 01 Jan 2025 00:00:00 GMT

Título: Investigation of the potential of commercial and wild Passiflora seed species as stilbenes sources. Autoria: ZOMER, A. P. L.; RODRIGUES, C. A.; ROTTA, E. M.; JUNQUEIRA, N. T. V.; SANTOS, O. O.; VISENTAINER, J. V.; MALDANER, L. Conteúdo: Abstract: Passion fruit seeds, a byproduct of juice processing, are rich in bioactive stilbenes with health-promoting properties. This study investigated piceatannol and resveratrol in seeds from four commercial and sixteen wild Passiflora species using the μ-QuEChERS method combined with UHPLC-MS/MS analysis. The method showed good analytical performance, with linearity (R2 ≥ 0.991), LOQ ≤ 20 μg kg–1, and RSD < 11%. Piceatannol and resveratrol were found in 70 and 60% of the analyzed species, respectively. Piceatannol was found in significantly higher amounts (0.6–55.2 mg kg–1) in 95% of these species, with values up to 56 times greater than resveratrol (0.3–7.5 mg kg–1). The highest piceatannol amounts were observed in the wild species P. longifilamentosa (55.2 mg kg–1) and P. edulis x P. caerulea (44.7 mg kg–1). These findings highlight Passiflora seeds as a valuable natural source of piceatannol, supporting their potential applications in functional foods, cosmetics, and pharmaceutical products.