Resistant Starch Content Is Related to Granule Size in Barley

Physical properties of resistant starch (RS) were examined in a range of barley genotypes to determine the contribution of starch and seed physical characteristics to the RS component. Thirty‐three barley genotypes were studied, which varied significantly in their RS, amylose, and starch contents and grain yield. From 33 genotypes, 13 exhibiting high RS were selected for detailed physicochemical analysis of starch. In high‐RS varieties, granule size and number were unimodal, compared with normal starches from a reference genotype, which showed a bimodal distribution. Principal component analysis (PCA) showed that a higher content of granules <15 µm was positively correlated with RS and amylose content, whereas the proportion of granules 15–45 µm was negatively correlated with the RS and amylose contents. Physical fractionation of starches by centrifugation into different population sizes demonstrated that size alone is not an accurate indicator of the population of A‐type and B‐type granules within a given genotype. PCA also showed that large 15–45 µm granules were positively correlated with seed thickness and that thousand grain weight was positively correlated with seed width. High‐RS and high‐amylose genotypes showed variation in overall yield and starch content, with some genotypes showing yield comparable to the reference genotype. Analysis of amylopectin chain length distribution showed that high amylose or RS content was not associated with a higher proportion of amylopectin long chains when compared with either waxy or reference (normal) barley genotypes. This study highlights useful markers for screening barley genotypes with favorable starch characteristics.     

Evaluation of fungicides for Haliphthoros milfordensis and their toxicity to juvenile European lobsters

Twenty-two potentially fungitoxic compounds were evaluated for their in vitro inhibition of the mycelial growth of Haliphthoros milfordensis. Chemicals with a minimum inhibitory concentration of 10 ppm or less were further tested for toxicity to juvenile European lobsters. Of these compounds, malachite green and Furanace had the lowest minimum inhibitory concentrations at 0.25 and 2.5 ppm respectively. Acriflavine, crystal violet, methylene blue, nifuroxime, butyl paraben and chloroxine were inhibitory to the fungus at a concentration of 10 ppm. Dip and swab applications were tested to assess in vivo toxicity to lobsters of the effective chemicals.     

Effect of dietary lipoic acid on metabolic hormones and acute-phase proteins during challenge with infectious bovine rhinotracheitis virus in cattle

OBJECTIVE: To determine the effect of dietary supplemental lipoic acid (LA) on serum concentrations of metabolic hormones and acute-phase proteins of steers challenged with infectious bovine rhinotracheitis virus (IBRV). ANIMALS: 32 steers. PROCEDURES: Steers were randomly assigned to 4 treatments: negative control (NC; no LA, no IBRV challenge), control (CON; no LA, IBRV challenge), 16 mg of LA/kg of body weight (BW)/d plus IBRV challenge (LA16), and 32 mg of LA/kg of BW/d plus IBRV challenge (LA32). Following a 21-day adaptation period, CON, LA16, and LA32 steers received IBRV (2 mL/nostril [day 0]); NC steers received saline (0.9% NaCl) solution. Blood samples, nasal swab specimens, BW, and rectal temperatures were obtained 0, 1, 3, 5, 7, 14, and 21 days after challenge. Serum was analyzed for concentrations of haptoglobin, amyloid-A, leptin, and anti-IBRV antibodies. RESULTS: Steers fed LA32 began gaining BW by day 7, whereas BW of CON and LA16 steers declined. Serum haptoglobin concentration of LA32 steers was lower than that of CON and LA16 steers on day 7. Serum neutralization titers for 30 of 32 steers were negative for anti-IBRV antibodies before challenge; however, all steers (including NCs) had antibodies on day 21. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that LA supplementation augmented certain aspects of the immune response; LA32 steers had a more rapid recovery from IBRV viral challenge than did others.