Elemental Uptake in Relation to Root Characteristics of Tall Fescue

HiMag, an accession of tall fescue (Festuca arundinacea Schreb.), was selected for high magnesium (Mg) concentration in leaves to reduce grass tetany risk to ruminants. However, the mechanism for enhanced Mg uptake in HiMag leaves has not been determined. The objective was to investigate if increased Mg uptake in HiMag could be explained by differences in elemental distribution among plant parts, root characteristics, or organic acid concentrations compared to its parental cultivars, ‘‘Kentucky 31’’ (KY31) and ‘‘Missouri 96’’ (MO96). The study was conducted on a surface-irrigated calcareous Portneuf silt loam (coarse-silty, mixed, mesic, Durinodic Xeric Haplocalcid). Vegetation and soil cores of 7.6-cm diameter were sampled to a 45-cm soil depth in 15-cm increments. Mass and ash were determined for leaves, crowns, and roots. Leaf area, root length, root area, root length density, elemental concentration, and uptake [potassium (K), calcium (Ca), Mg, sodium (Na), and phosphorus (P)], and malate and citrate concentrations also were determined. Leaf Mg concentration was higher in HiMag than parental cultivars. HiMag generally did not differ in crown and root elemental concentrations from its parents. Risk of causing grass tetany, indicated by leaf K/(Ca+Mg), was lower in HiMag than KY31 and MO96 in both 1994 (P=0.03) and 1995 (P=0.01). Root length, area, and mass were not related to cation concentrations in the three tall fescue accessions, suggesting that HiMag may have an active uptake or transport mechanism for Mg

Determining animal preference for grasses: Methods and error analysis

Grazing preference of 8 tall fescues was evaluated by 1) clipping and weighing forage before and after grazing (CW), 2) a selection ratio (SR), and 3) preference scores (PS). The coefficients of variation were 96, 52, and 20% for SR, CW, and PS methods, respectively. The ranking of preference was similar for CW, SR, and PS methods. The PS method was done in 6% of the time and with less error than CW and SR, used the entire row, and was nondestructive

Cattle grazing preference among eight endophyte-free tall fescue cultivars

`HiMag' tall fescue (Festuca arundinacea Schreb.) was selected for high Mg concentration to reduce grass tetany risk to ruminants, but neither animal preference nor consumption of HiMag were known. The objectives were to evaluate methods of quantifying preference and to determine intake and preference by cattle (Bos taurus L.) of HiMag relative to seven other tall fescues. All entries were free of a fungal endophyte [Neotyphodium coenophialum (Morgan-Jones & Gams) Glen, Bacon & Hanna] that reduces cattle performance. The experimental design was a randomized complete block with three replications of eight cultivars nested within each of three test pastures. Six heifers grazed the vegetative to boot-stage pastures for 48 h in May, June, August, and September of 1993 and 1994. The pastures, located at 1200 m elevation, were furrow irrigated. Pre- and post-grazed forage were clipped and weighed to determine yield and utilization (48-h utilization < 50%). Preference scoring of 0 to 10 (0 to 100% of forage eaten) was done by four trained observers at 24, 30, and 48 h. The heifers quickly learned to distinguish between cultivars, and their order of preference was Kenhy > KY 31 > HiMag = Barcel = Cl = Stargrazer > M096 = Mozark. The cultivar x trial(year) interaction for preference indicated that cultivars responded differently to weather conditions, which in turn affected animal preference. Preference scoring had high repeatability and ranked cultivars similarly to the clip-and-weigh method of measuring utilization. Preference scoring was accomplished with 27% of the experimental error and only 6% of the time required for clip-and-weigh. Only 44% of the variation in preference score (PS) was explained by the model: PS = 8.8 - 1.1(Mg DM yield ha-1). Estimated dry matter (DM) intake of HiMag was 6.4 kg (animal unit day)-1. Consumption and preference of HiMag by cattle are satisfactory relative to other tall fescue cultivars

Disrupting Circadian Homeostasis of Sympathetic Signaling Promotes Tumor Development in Mice

and why disruption of circadian rhythm may lead to tumorigenesis. oncogenic potential, leading to tumor development in the same organ systems in wild-type and circadian gene-mutant mice. is a clock-controlled physiological function. The central circadian clock paces extracellular mitogenic signals that drive peripheral clock-controlled expression of key cell cycle and tumor suppressor genes to generate a circadian rhythm in cell proliferation. Frequent disruption of circadian rhythm is an important tumor promoting factor

Cluster Headache Genomewide Association Study and Meta-Analysis Identifies Eight Loci and Implicates Smoking as Causal Risk Factor

Objective: The objective of this study was to aggregate data for the first genomewide association study meta-analysis of cluster headache, to identify genetic risk variants, and gain biological insights. Methods: A total of 4,777 cases (3,348 men and 1,429 women) with clinically diagnosed cluster headache were recruited from 10 European and 1 East Asian cohorts. We first performed an inverse-variance genomewide association meta-analysis of 4,043 cases and 21,729 controls of European ancestry. In a secondary trans-ancestry meta-analysis, we included 734 cases and 9,846 controls of East Asian ancestry. Candidate causal genes were prioritized by 5 complementary methods: expression quantitative trait loci, transcriptome-wide association, fine-mapping of causal gene sets, genetically driven DNA methylation, and effects on protein structure. Gene set and tissue enrichment analyses, genetic correlation, genetic risk score analysis, and Mendelian randomization were part of the downstream analyses. Results: The estimated single nucleotide polymorphism (SNP)-based heritability of cluster headache was 14.5%. We identified 9 independent signals in 7 genomewide significant loci in the primary meta-analysis, and one additional locus in the trans-ethnic meta-analysis. Five of the loci were previously known. The 20 genes prioritized as potentially causal for cluster headache showed enrichment to artery and brain tissue. Cluster headache was genetically correlated with cigarette smoking, risk-taking behavior, attention deficit hyperactivity disorder (ADHD), depression, and musculoskeletal pain. Mendelian randomization analysis indicated a causal effect of cigarette smoking intensity on cluster headache. Three of the identified loci were shared with migraine. Interpretation: This first genomewide association study meta-analysis gives clues to the biological basis of cluster headache and indicates that smoking is a causal risk factor

Cattle grazing preference among eight endophyte-free tall fescue cultivars

`HiMag' tall fescue (Festuca arundinacea Schreb.) was selected for high Mg concentration to reduce grass tetany risk to ruminants, but neither animal preference nor consumption of HiMag were known. The objectives were to evaluate methods of quantifying preference and to determine intake and preference by cattle (Bos taurus L.) of HiMag relative to seven other tall fescues. All entries were free of a fungal endophyte [Neotyphodium coenophialum (Morgan-Jones & Gams) Glen, Bacon & Hanna] that reduces cattle performance. The experimental design was a randomized complete block with three replications of eight cultivars nested within each of three test pastures. Six heifers grazed the vegetative to boot-stage pastures for 48 h in May, June, August, and September of 1993 and 1994. The pastures, located at 1200 m elevation, were furrow irrigated. Pre- and post-grazed forage were clipped and weighed to determine yield and utilization (48-h utilization < 50%). Preference scoring of 0 to 10 (0 to 100% of forage eaten) was done by four trained observers at 24, 30, and 48 h. The heifers quickly learned to distinguish between cultivars, and their order of preference was Kenhy > KY 31 > HiMag = Barcel = Cl = Stargrazer > M096 = Mozark. The cultivar x trial(year) interaction for preference indicated that cultivars responded differently to weather conditions, which in turn affected animal preference. Preference scoring had high repeatability and ranked cultivars similarly to the clip-and-weigh method of measuring utilization. Preference scoring was accomplished with 27% of the experimental error and only 6% of the time required for clip-and-weigh. Only 44% of the variation in preference score (PS) was explained by the model: PS = 8.8 - 1.1(Mg DM yield ha-1). Estimated dry matter (DM) intake of HiMag was 6.4 kg (animal unit day)-1. Consumption and preference of HiMag by cattle are satisfactory relative to other tall fescue cultivars