Interrelações entre minerais no solo, plantas forrageiras e tecido animal no norte de Mato Grosso 4. Zinco, magnésio, sódio e potássio

An experiment was conducted with samples from six farms in northearn Mato Grosso, Brazil, to study the interrelationships among levels of minerals in soil, forage, and animal tissues during the wet and dry seasons of the year. Soil extractable Zn levels were low in three out of six farms. Forage Zn levels were defficient in five farms. Levels of Zn in the liver were defficient in all six farms, being much lower (68 ppm) during the wet season than during the dry season (113 ppm). Magnesium levels in soil were low in one farm and adequated in five. Forage and animal tissue Mg levels were adequated in all six farms. Soil extractable sodium was normal and the salinity in all six farms was considered negligible. Forage sodium was highly defficient, being able to meet only between 14 to 30% of the animal requirements. Soil potassium levels were low in two out of six farms, but forage levels were adequate in all six farms to meet the requirement of grazing beef cattle.Levantamento das deficiências minerais de seis fazendas localizadas ao norte do Estado de Mato Grosso, tendo sido amostrados os solos, plantas forrageiras e tecido animal, nas estações seca e chuvosa. Foram constatadas deficiências de Zn no solo em três das seis fazendas estudadas. Cinco das seis fazendas apresentaram deficiência de zinco nas forrageiras. Os níveis de Zn no fígado dos animais foram deficientes em todas as seis fazendas, mas sendo muito mais deficientes ainda no período chuvoso (68 ppm) do que no período seco, (113 ppm). Os níveis de Mg nos solos foram mais baixos em apenas uma fazenda. Nas forrageiras e no tecido dos animais amostrados, os níveis de Mg foram normais. Os níveis de Na nos solos foram considerados normais, e a salinidade nas regiões estudadas foi considerada insignificante. Em todas as fazendas, as forrageiras mostraram-se altamente deficientes em Na, satisfazendo apenas entre 14 a 30% das exigências nutricionais dos bovinos. Os níveis de K nos solos mostraram-se deficientes em duas das seis fazendas estudadas. As forrageiras apresentaram níveis médios adequados às exigências nutricionais dos bovinos em todas as fazendas

Physical activity calorie expenditure (PACE) labels in worksite cafeterias: Effects on physical activity

Background: Regular physical activity is an important component of healthy living and wellbeing. Current guidelines recommend that adults participate in at least 150 min of moderate or vigorous-intensity physical activity weekly. In spite of the benefits, just over half of U.S. adults meet these recommendations. Calorie-only food labels at points of food purchase have had limited success in motivating people to change eating behaviors and increase physical activity. One new point of purchase approach to promote healthy behaviors is the addition of food labels that display the physical activity requirement needed to burn the calories in a food item (e.g. walk 15 min). Methods: The Physical Activity Calorie Expenditure (PACE) Study compared activity-based calorie-expenditure food labels with calorie-only labels at three Blue Cross and Blue Shield of North Carolina worksite cafeterias. After 1 year of baseline data collection, one cafeteria had food items labeled with PACE labels, two others had calorie-only food labels. Cohort participants were asked to wear an accelerometer and complete a self-report activity questionnaire on two occasions during the baseline year and twice during the intervention year. Results: A total of 366 study participants were included in the analysis. In the PACE-label group, self-reported physical activity increased by 13-26% compared to the calorie-only label group. Moderate-to-vigorous physical activity (MVPA) increased by 24 min per week in the PACE-label group compared to the calorie-label group (p = 0.06). Changes in accelerometer measured steps, sedentary time, and MVPA had modest increases. Change ranged from 1 to 12% with effect size values from 0.08 to 0.15. Baseline physical activity level significantly moderated the intervention effects for all physical activity outcomes. Participants in both label groups starting in the lowest tertile of activity saw the largest increase in their physical activity. Conclusion: Results suggest small positive effects for the PACE labels on self-reported and objective physical activity measures. Minutes of weekly MVPA, strength training, and exercise activities showed modest increases. These results suggest that calorie-expenditure food labels may result in some limited increases in physical activity