Increasing bitterbrush nutrient quality with 2,4-D, mowing, and burning in southcentral Wyoming

Effects of burning, mowing, and 2,4-D on antelope bitterbrush (Purshia tridentata Pursh.) nutrient contents were evaluated in southcentral Wyoming. During the first growing season following treatments, spraying of 2,4-D increased bitterbrush nitrogen (N) contents from 1.5 to 1.9%, phosphorus (P) from 0.12 to 0.15%, and in vitro digestible dry matter (IVDDM) from 44.1 to 48.4%. Mowing increased N from 1.5 to 1.7%, P from 0.12 to 0.16%, and IVDDM from 44.1 to 46.1%. Burning increased N from 1.4 to 1.9%, P from 0.11 to 0.17%, ash from 3.7 to 5.3%, and IVDDM from 47.4 to 51.0%, and decreased gross energy from 4,640 to 4,380 kcal/g. There were no differences in N and IVDDM contents among treatments at the end of the second growing season, but P content was still greater in mowed bitterbrush regrowth than on untreated bitterbrush. Ash contents were not affected by treatments, but were higher in summer (3.9%) than in winter (2.4%). Gross energy contents varied only 5 to 10% among all treatments and seasons. Correlation coefficients between N, P, ash, and IVDDM contents varied from +0.54 to +0.76, and all of these nutrients were negatively correlated with gross energy. Bitterbrush nutrient contents can be increased by shrub management practices, but short-term responses require that small portions of the total area be treated annually in a rotational shrub management program.This material was digitized as part of a cooperative project between the Society for Range Management and the University of Arizona Libraries.The Journal of Range Management archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform August 202

Sites, mowing, 2,4-D, and seasons affect bitter-brush twig morphology

Effects of site factors, mowing, 2,4-D, and seasons on antelope bitterbrush (Purshia tridentata Pursh.) twig length, basal and tip diameters, and weight were evaluated in southcentral Wyoming. Linear regression coefficients for twig length regressed on basal diameter were greater on productive sites than on less productive sites, greater on mowed areas than on sprayed or untreated areas, and greater in late fall because of leaves than in late winter. Twig elongation continued after data collection in early November. Twig length was more variable and more sensitive to different environmental conditions than twig basal diameter, tip diameter, or weight. Twig length accounted for 80-86% of the variation in twig weight. Sites, shrub management practices, and seasons do affect bitterbrush twig morphology, but habitat managers can use twig length-diameter-weight relations in this vegetation type to estimate utilization if the sampling is stratified along environmental gradients.This material was digitized as part of a cooperative project between the Society for Range Management and the University of Arizona Libraries.The Journal of Range Management archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform August 202

Sites, mowing, 2,4-D, and seasons affect bitterbrush values

This study was conducted in a sagebrush-bitterbrush vegetation type in southcentral Wyoming to compare the effects of mowing and 2,4-D application on shrub cover and bitterbrush (Purshia tridentata Pursh) use, preference values, browse values, and residual twig weight after summer/fall browsing by cattle and winter big game use. Areas 3 to 6 ha in size were mowed, sprayed with 2,4-D, or left untreated on 4 different sites. Total shrub cover was reduced from 38% (53% mountain big sagebrush (Artemisia tridentata spp. vaseyana), 37% bitterbrush) to 23% (38% sagebrush, 52% bitterbrush) by mowing, and to 17% (18% sagebrush, 64% bitterbrush) by herbicide application. Twig weight use was greater on mowed areas, on the more productive sites, and during summer cattle browsing when leaves were present than during winter browsing by big game. Frequency of use was inversely related to bitterbrush availability, although the relationship was confounded by different snow depths on different sites. Utilization values based on basal diameter were more sensitive to site and treatment effects than length and weight utilization values, but were influenced by differences in twig morphology and did not reflect differences in twig use, preference values, browse values, or browsing residual weights. Mowing produced the greatest preference values and browsing residual weights for cattle browsing and the greatest browse values for both cattle and big game. Preference values, browse values, and browsing residual weight appear to be useful indicators of site, treatment, and browsing effects.This material was digitized as part of a cooperative project between the Society for Range Management and the University of Arizona Libraries.The Journal of Range Management archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform August 202

Enhanced infection prophylaxis reduces mortality in severely immunosuppressed HIV-infected adults and older children initiating antiretroviral therapy in Kenya, Malawi, Uganda and Zimbabwe: the REALITY trial

Meeting abstract FRAB0101LB from 21st International AIDS Conference 18–22 July 2016, Durban, South Africa. Introduction: Mortality from infections is high in the first 6 months of antiretroviral therapy (ART) among HIV‐infected adults and children with advanced disease in sub‐Saharan Africa. Whether an enhanced package of infection prophylaxis at ART initiation would reduce mortality is unknown. Methods: The REALITY 2×2×2 factorial open‐label trial (ISRCTN43622374) randomized ART‐naïve HIV‐infected adults and children >5 years with CD4 <100 cells/mm3. This randomization compared initiating ART with enhanced prophylaxis (continuous cotrimoxazole plus 12 weeks isoniazid/pyridoxine (anti‐tuberculosis) and fluconazole (anti‐cryptococcal/candida), 5 days azithromycin (anti‐bacterial/protozoal) and single‐dose albendazole (anti‐helminth)), versus standard‐of‐care cotrimoxazole. Isoniazid/pyridoxine/cotrimoxazole was formulated as a scored fixed‐dose combination. Two other randomizations investigated 12‐week adjunctive raltegravir or supplementary food. The primary endpoint was 24‐week mortality. Results: 1805 eligible adults (n = 1733; 96.0%) and children/adolescents (n = 72; 4.0%) (median 36 years; 53.2% male) were randomized to enhanced (n = 906) or standard prophylaxis (n = 899) and followed for 48 weeks (3.8% loss‐to‐follow‐up). Median baseline CD4 was 36 cells/mm3 (IQR: 16–62) but 47.3% were WHO Stage 1/2. 80 (8.9%) enhanced versus 108(12.2%) standard prophylaxis died before 24 weeks (adjusted hazard ratio (aHR) = 0.73 (95% CI: 0.54–0.97) p = 0.03; Figure 1) and 98(11.0%) versus 127(14.4%) respectively died before 48 weeks (aHR = 0.75 (0.58–0.98) p = 0.04), with no evidence of interaction with the two other randomizations (p > 0.8). Enhanced prophylaxis significantly reduced incidence of tuberculosis (p = 0.02), cryptococcal disease (p = 0.01), oral/oesophageal candidiasis (p = 0.02), deaths of unknown cause (p = 0.02) and (marginally) hospitalisations (p = 0.06) but not presumed severe bacterial infections (p = 0.38). Serious and grade 4 adverse events were marginally less common with enhanced prophylaxis (p = 0.06). CD4 increases and VL suppression were similar between groups (p > 0.2). Conclusions: Enhanced infection prophylaxis at ART initiation reduces early mortality by 25% among HIV‐infected adults and children with advanced disease. The pill burden did not adversely affect VL suppression. Policy makers should consider adopting and implementing this low‐cost broad infection prevention package which could save 3.3 lives for every 100 individuals treated