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Riscos ocupacionais durante o processo de secagem do café
(Universidade Federal de Lavras, 2025-07-31) Faria, Juliana Aparecida Alves de; Tavares, Ednilton de Andrade; Ferraz, Patrícia Ferreira Ponciano; Gandia, Rômulo Marçal; Oliveira, Filipe da Silva de; Coradi, Paulo Carteri; Rabelo, Giovanni Francisco
This research aimed primarily to investigate the occupational risks associated with heat exposure in agricultural activities, with an emphasis on coffee drying processes, through an approach structured into three complementary studies. The first article conducted a systematic review of the literature using the Preferred Reporting Items for Systematic Reviews and MetaAnalysis (PRISMA), focusing on thermal exposure of agricultural workers. The analysis revealed a scarcity of research focused on operations such as grain drying and highlighted the need for more in-depth studies on the impacts of heat as an occupational risk factor in open and semi-open environments. The second article was developed through a review of bibliographic sources on Standard Operating Procedures (SOP) focused on agricultural activities. Publications from 2020 to 2025 were considered, with the indexers: 'Operational Procedures,' 'Agribusiness,' 'Mechanical Drying of Coffee,' and 'Occupational Risks.' The study revealed the scarcity of SOP practices in agricultural production segments. In the third article, temperature levels and indicators of heat stress were quantified at coffee drying sites to identify thermal risk zones. The adopted methodology involved measuring the body temperature of agricultural workers and the operational perimeter of the furnaces at two coffee plantations in Minas Gerais. For the measurements, digital thermo-hygrometers, globe thermometers, and infrared thermometers were used. The results indicated a maximum temperature of 31.5ºC at a distance of 0.5 m from the furnace, and a minimum of 26ºC at a distance of 1.5 m, values above those recommended by the regulatory standard, confirmed through the application of mathematical models, with means of R² ≥ 0.90 / P < 4, statistically significant. The temperature behavior in WBGT follows the records for Sample 1 and 2 (R² = 0.8 – 0.9). The application of the Spearman coefficient showed a strong correlation between the operator's temperature and the furnace (0.48**), dryer (0.61**), and environment (0.37**). The data were submitted to different mathematical models to verify the legitimacy of the purposes, and the results obtained were consistent. The studies conducted pave the way for technical solutions to improve working conditions in the agro-industrial sector. The value of this research lies in the integration of systematic review, field analysis, and the use of applied science peers, providing practical and theoretical support for the development of safer production environments.
Evaluación de la marcha a través de acelerometría en equinos adultos de la raza Mangalarga Marchador
(Universidade Federal de Lavras, 2025-09-12) Lucastegui, Adriana Inés; Moura, Raquel Silva de; Meirelles, Sarah Laguna da Conceição; Meirelles, Sarah Laguna da Conceição; Ribeiro, Alex de Oliveira; Penoni, Álvaro César de Oliveira; Muriel, Marcos Germán
Over time, the study of equine biomechanics has been fundamental for understanding and classifying different gaits. In the specific case of the Mangalarga Marchador breed, these studies have mainly used the kinematic approach to biomechanics through the use of high-resolution cameras. However, to date, there are few studies on this breed using the kinetic approach, particularly involving accelerometers. The objectives of this study were to describe kinematic and kinetic variables of the gait of adult Mangalarga Marchador (MM) horses, exploring the influence of both intrinsic and extrinsic factors on these variables. Data were collected from 48 adult horses definitively registered in the MM5 and MM6 books (with known pedigree) of the Brazilian Association of Mangalarga Marchador Horse Breeders, using the Equimetrix® system (Centaure Métrix, Fontainebleau, France). These animals were evaluated at three different gait speeds (short, medium, and extended) on a compacted dirt track, covering a distance of 60 meters. The following kinematic variables were evaluated: speed, stride frequency, stride length, regularity, symmetry, and dorsoventral displacement; and the kinetic variables: dorsoventral power, propulsion force, and mediolateral power. Although differences were observed in many of the variables analyzed, stride frequency and stride length showed significant differences (p<0.05), regardless of the factor analyzed. Additionally, differences were recorded in the kinetic variables, mainly in propulsive force and dorsoventral power, showing a strong positive correlation between these variables across all three gaits. The results obtained mark a starting point for studying the gait with greater precision and objectivity, providing key information in a still scarcely explored area, such as kinetics in Mangalarga Marchador horses, which will help enrich the available knowledge for both the scientific community and breeders regarding the selection and training of horses for marcha.
A experiência sensorial e simbólica no consumo de carnes nobres no Brasil: uma análise do comportamento do consumidor de luxo
(Universidade Federal de Lavras, 2025-12-11) Lima, Diego de Rezende; Carneiro, João de Deus Souza; Andrade, Lilia Paula; Fontan, Gabrielle Cardoso Reis
This study investigated how Brazilian consumers of premium beef attribute symbolic, emotional, and performative meaning to their purchases, examining how practices of distinction, technical expertise, and identity performances shape the consumption experience. Using a qualitative interpretivist approach, in-depth interviews and photo-elicitation were conducted with 20 habitual consumers and analyzed through a triangulated method integrating Thematic Analysis and Critical Discourse Analysis. The findings reveal that premium beef consumption extends beyond functional attributes and operates as an aesthetic and affective ritual in which pleasure, pride, belonging, and moral rationalizations compose what is defined as the emotional essentiality of food-related luxury. Technical vocabulary and gastronomic expertise serve as legitimizing cultural capital, functioning as symbolic markers of distinction. A comparative analysis identified two consumer profiles: traditional, who rely on embodied knowledge and experience consumption as an intimate and authentic practice; and emergent, who actively build expertise and perform their consumption in digital environments as a strategy for visibility and social legitimation. Overall, the results show that the perceived value of premium beef emerges from the interplay between emotion, aesthetics, knowledge, and performance, positioning food-related luxury as a central practice in the contemporary construction of identity, belonging, and prestige. These findings highlight the importance of symbolic and affective dimensions in understanding premium product consumers and offer insights for experience design and market positioning within the luxury food sector.
Interaction of flint corn grain processing and urea source, and the inclusion of calcareous marine algae in finishing diets for Nellore cattle: effects on growth performance, carcass traits, and nutritional characteristics
(Universidade Federal de Lavras, 2025-07-09) Fávero, Igor Gomes; Batista, Erick Darlisson; Orientador; Casagrande, Daniel Rume; Batista, Erick Darlisson; Casagrande, Daniel Rume; Costa, Diogo Fleury Azevedo; dc.contributor.referee1; dc.contributor.referee2; dc.contributor.referee3; dc.contributor.referee4; dc.contributor.referee5
Global population growth has intensified the demand for productive and environmentally sustainable livestock systems. In this context, Lithothamnium calcareum, a calcareous marine algae, has emerged as a natural buffering agent to improve ruminal fermentation and reduce methane emissions. Thus, the objective of this study was to evaluate the effects of L. calcareum supplementation on feedlot performance, carcass traits, nutrient digestibility, nitrogen metabolism, urinary and fecal pH, and enteric methane emissions in Nellore heifers during the finishing phase. Thirty-six heifers with an initial body weight (BW) of 270 ± 7 kg were allocated in individual pens and distributed in a randomized complete block design. The experimental diets were formulated with a 25:75 forage-to-concentrate ratio (DM basis) and provided ad libitum, with daily adjustments to control feed refusals. Two treatments were evaluated: 1) Sodium bicarbonate (1.8% DM in the diet, providing 110 g/heifer/day), and 2) Calcareous marine algae (supplemented with 60 g of L. calcareum /heifer/day). The experiment lasted 96 days, including 12 days of dietary adaptation followed by 84 days on the finishing diet. Refusals were collected and quantified daily to estimate dry matter intake (DMI), by calculating the difference between the amount offered and refused. BW was measured on days 0, 13, 41, 69 and 96, before the morning feeding. Enteric methane (CH₄) emissions were measured using the sulfur hexafluoride (SF₆) tracer gas technique during three distinct periods of the experiment: days 21 to 25, 49 to 53, and 77 to 81. Fecal and urine samples were also collected during three periods (days 27–32, 55–60, and 83–88). Data was analyzed using the MIXED procedure of SAS 9.4. There were no significant treatment effects on feedlot performance (P ≥ 0.560), carcass traits (P ≥ 0.681) and apparent total tract digestibility (P ≥ 0.212). Urine pH was significantly lower for heifers consuming calcareous marine algae (P ≤ 0.001) compared to those receiving sodium bicarbonate. Fecal N excretion (53.82 vs. 47.87 g/day; P = 0.079) tended to be lower in heifers fed with calcareous marine algae. Heifers fed diets supplemented with calcareous marine algae showed a tendency for an 8.2% reduction (P = 0.075) in enteric methane emissions compared to those receiving sodium bicarbonate. In summary, L. calcareum proved to be a viable natural alternative to sodium bicarbonate in finishing diets for Nellore heifers, maintaining performance and carcass traits, with potential to enhance ruminal microbial activity and reduce enteric CH₄ emissions, although further studies are needed.
Diversidade e distribuição de sequências repetitivas em tandem em espécies de Cynodon rich. (Poaceae)
(Universidade Federal de Lavras, 2025-10-24) Belo, Giovanna Angeli; Techio, Vânia Helena; Torres, Giovana Augusta; Moraes, Ana Paula de; Bustamante, Fernanda de Oliveira; Baez, Mariana Alejandra
The genus Cynodon (Poaceae) comprises species widely distributed in tropical and subtropical regions, exhibiting morphological, cytogenetic, and genomic variability. Despite its agronomic and ecological importance, studies on the organization and evolution of its repetitive elements remain limited, especially satellite DNAs (satDNAs), which may act as chromosomal markers and provide insights into the evolutionary history of the group. In this study, a comparative cytogenomic characterization of diploid and polyploid Cynodon species was performed, focusing on the identification and mapping of satDNAs. In silico analyses, conducted using genomic data, enabled the identification of satDNA families, which were subsequently validated by Fluorescent in situ hybridization (FISH). Chromosomal distribution patterns, the presence of heteromorphisms, and the potential of these sequences as cytogenetic markers were evaluated. Comparative analysis of the idiograms revealed heteromorphism patterns between homologous chromosomes, possibly associated with the reorganization of repetitive sequences. Greater genomic proximity was observed between C. dactylon and C. nlemfuensis, which shared four satellite families and exhibited highly syntenic idiograms, whereas C. incompletus showed a higher number of species-specific sequences in the in silico analyses and an idiogram distinct from the other species. Difficulties were encountered in proposing an idiogram model based solely on the markings detected in tetraploid C. transvaalensis, mainly due to the high number of chromosomes with similar sizes and labeling patterns, as well as differences observed among homologous chromosomes themselves, attributed to the high heterozygosity of the genus. The results obtained in this thesis reinforce the importance of satDNAs as a valuable tool for chromosome identification, while also highlighting the genomic complexity of the tandem repetitive fraction in the genus Cynodon.