Sprout development and processing quality changes in potato tubers stored under ethylene: 1. Effects of ethylene concentration

Ethylene effectively inhibits sprouting of potatoes (Solanum tuberosum L.) during storage, but it often darkens fry color. The objective of the work described here was to determine if altering the concentration of ethylene applied would reduce the darkening while retaining adequate sprout inhibition. Trials were conducted over three consecutive years (1991–1992, 1992–1993, and 1993–1994). Tubers of cv Russet Burbank (ca 150–300 g) were stored at 9 C for 25 wk in closed chambers in a refrigerated room under continuous exposure to 0.4, 4, 40, or 400 µL L^?1 ethylene gas delivered with the ventilation airstream (ca 0.5 air exchanges per h, for 6 h each day). Untreated control and chlorpropham-treated (CIPC) check tubers were stored under the same conditions but without ethylene supplementation. Sprout number, length, and biomass, fry color, loss of tuber mass, disease, and dry matter content were evaluated at 5-wk intervals. Dose-dependent effects (400>40>4>0.4 µL L^?1) of ethylene on sprout growth and fry color were observed. The 400, 40, and 4 µL L^?1 ethylene treatments inhibited sprout growth as effectively as CIPC, whereas in 0.4 µL L^?1 ethylene sprouting was midway between CIPC and the untreated control. Sprout mass and maximum sprout length in all ethylene treatments were significantly lower (P<0.05) than in the untreated control. Compared with the initial value (57.3 Agtron reflectance units [ARu]), after 5 wk of storage fry color was up to 5 ARu darker in the ethylene treatments, but recovered steadily at the subsequent evaluation dates. At 25 wk of storage the fry color of tubers from the 40 and 4 µL L^?1 ethylene treatments were, however, still darker than tubers stored with CIPC. Inhibition of sprout growth was slightly more effective in the 400 and 40 µL L^?1 ethylene treatments than in 4 µL L^?1, although there were no significant differences (P<0.01) in fry color between these treatments. In comparison with the other ethylene treatments, fry color in 0.4 µL L^?1 ethylene was lighter, but inhibition of sprout growth was significantly (P<0.05) poorer. There were no differences in tuber disease incidence or dry matter content between the treatments. At 25 wk, the untreated tubers had ca 50% greater loss of tuber mass than any other treatment, attributable to their heavy sprouting. Loss of tuber mass in the ethylene treatments was not significantly different (P<0.001) from that in the CIPC treatment.     

Contrasting Preference for Grassland Landscapes Among Population Groups in the Central and Southern Great Plains

Recent opposition to the rangeland management paradigm of achieving uniform, moderate grazing across entire landscapes has emerged because heterogeneity is recognized as the foundation of biodiversity, ecosystem resilience, and multifunctionality of agricultural landscapes. Agriculture production goals appear to drive the traditional rangeland management focus on homogeneity and uniformity. To determine if preference for homogeneity is a broadly applicable social construct or one limited to agricultural producers, we determined preferences for heterogeneous grassland landscapes expressed by three study populations—managers of working lands (ranchers), natural resource professionals (grassland/rangeland specialists), and the general population living in rangeland regions within the US Great Plains. We distributed surveys that included photographs of landscapes and patterned images to assess preference. Preference for heterogeneous landscapes among ranchers, natural resource professionals, and the general population in our study area were generally consistent with the central paradigm of managing rangeland for homogeneity. However, we discovered that people, across geographic location and population group, clearly prefer heterogeneous patterned images to homogeneous patterned images. This suggests that preference for homogeneity is acquired.     

Retained Woody Structure in 1- to 2-Year-Old Loblolly Pine (Pinus taeda L.) Plantations in Mississippi,Louisiana, and Arkansas: Implications for Wildlife Conservation

Information regarding how site preparation techniques affect residual woody structure is lacking for the southern United States in spite of the importance of such structure for many wildlife species. Therefore, we documented retained structure in young loblolly pine (Pinus taeda L.) plantations established using four common site preparation regimes: mechanical only, chemical only, chemical + mechanical, or chemical + prescribed burning. Herbicides reduced live tree density and increased snag density relative to mechanical methods. Prescribed burning reduced density of coarse woody debris (CWD) along with density and volume of piled CWD relative to chemical and mechanical methods. Our results provide a baseline for further studies of wildlife and retained structure in southern pine forests.     

Effects of substituting soya bean meal (SBM) with blood meal (BM) on biochemical profile of pregnant pigs

Twenty-four Large White × Landrace crossbreed primigravid pigs, aged 7.50 to 8.00 months weighing between 86.15 and 88.24 kg were used to study the effects of feeding graded levels of soya bean meal (SBM) replaced blood meal (BM) diets on serum biochemical profile in gestating pigs. The pigs were randomly allotted to four finisher diets formulated such that BM replaced SBM at 0.0, 50.0, 75.0 and 100.0 %, respectively. The diets were T1 (100.0 % SBM, 0.0 % BM), T2 (50.0 % SBM, 50.0 % BM), T3 (25.0 % SBM, 75.0 % BM) and T4 (0.0 % SBM, 100.0 % BM). Individual animal’s daily ration of the test diets was 2.20, 2.00 and 2.50 kg at stages one, two and three of gestation. Blood sampling and analysis for the effects of the test diets on biochemical profile of the experimental animals were carried out prior to conception, at weeks 3, 7 and 11 of gestation, respectively. The result showed no significant (P?≥?0.05) dietary treatment effects on total protein, albumin, globulin fraction, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, creatinine and urea profile of the pigs fed with BM diets when compared to the control fed with 100.0 % SBM. There was however a significant (P?≤?0.05) variation in these biochemical indices in all the experimental groups at different stages of gestation. It was concluded that BM can replace 100.0 % of SBM in the diets of pregnant pigs in the tropical humid environment without any deleterious effect on their health.     

Assessing the Suitability of a Partial Water Reuse System for Rearing Juvenile Chinook Salmon for Stocking in Washington State

Abstract

To assess the suitability of water reuse technology for raising Pacific salmon Oncorhynchus spp. for stocking purposes, fish health and welfare were compared between two groups of juvenile Chinook salmon O. tshawytscha from the same spawn: one group was reared in a pilot partial water reuse system (circular tanks), and the other group was reared in a flow-through raceway. This observational study was carried out over a 21-week period in Washington State. Reuse and raceway fish were sampled repeatedly for pathogen screening and histopathology; fin erosion and whole-blood characteristics were also evaluated. By the study's end, no listed pathogens were isolated from either cohort, and survival was 99.3% and 99.0% in the reuse and raceway groups, respectively. Condition factor was 1.28 in raceway fish and 1.14 in reuse fish; this difference may have been attributable to occasional differences in feeding rates between the cohorts. Fin indices (i.e., length of the longest dorsal or caudal fin ray, standardized by fork length) were lower in reuse fish than in raceway fish, but fin erosion was not grossly apparent in either cohort. The most consistent histological lesion was gill epithelial hypertrophy in reuse fish; however, blood analyses did not suggest any corresponding physiological imbalances. Overall, results suggest that water reuse technology can be employed in rearing juvenile anadromous salmonids for stocking purposes.

Received December 3, 2009; accepted February 14, 2011     

Prospective trial of autologous conditioned plasma versus hyaluronan plus corticosteroid for elbow osteoarthritis in dogs

This prospective, randomized, double-blinded trial compared outcomes in dogs with bilateral elbow osteoarthritis (OA) treated with hyaluronan plus methylprednisolone (HA + S) or autologous conditioned plasma (ACP^®; Arthrex). An investigator blinded to the treatments graded lameness (0–4) before and 6 months after a single injection with either HA + S or ACP. Clients were blinded to treatment and completed a validated survey before and 1, 6, 12, and 24 weeks after injection. Ten dogs (5 per group) completed all parts of the study. Pre-treatment lameness grades were 1.2 ± 0.97 for HA + S and 1.8 ± 1.1 for ACP and were not different between groups. Post-treatment lameness grades were 0.4 ± 0.55 for HA + S and 0.8 ± 0.64 for ACP with significant (P < 0.05) improvement with either treatment but without differences between groups. Client-based assessments demonstrated improvements in activity, lameness, and pain with HA + S and ACP. These data suggest that both treatments have beneficial effects for dogs with bilateral elbow OA.     

Penman-Monteith模型模拟Venlo型温室黄瓜植株蒸腾

准确模拟温室作物蒸腾对于制定科学合理的灌溉制度及温室环境调控具有重要意义,该研究基于2017年秋冬季和2018年春夏季Venlo型温室黄瓜生育期内微气象数据、黄瓜生长发育指标和植株蒸腾,对Penman-Monteith(PM)模型中关键参数—冠层阻力和空气动力学阻力进行研究。通过分析黄瓜叶片孔阻力与温室内气象因子的响应关系,构建了由黄瓜有效叶面积指数及叶片孔阻力模拟冠层阻力的子模型;采用基于风速的Perrier对数法和基于温室对流类型的热传输系数法计算温室内低风速环境下的空气动力学阻力,并评价不同方法的适用性。结果表明:叶片孔阻力与太阳辐射呈指数关系(R~2=0.89),可通过观测温室内太阳辐射计算黄瓜叶片孔阻力;应用热传输系数法确定空气动力学阻力时,温室内对流类型绝大多数时间为混合对流;2种方法计算的温室内空气动力学阻力变化幅度均较小,Perrier对数法计算的春夏季和秋冬季空气动力学阻力平均值分别为388和383 s/m,热传输系数法计算的空气动力学阻力平均值分别为141和158 s/m;基于2种空气动力学阻力计算方法,PM模型模拟的植株蒸腾与实测值均具有较好的一致性,但采用Perrier对数法计算空气动力学阻力时,PM模型低估了植株蒸腾,春夏季和秋冬季拟合线斜率分别为0.87和0.91;而采用热传输系数法计算空气动力学阻力时,PM模型可更准确的模拟该地区温室黄瓜植株蒸腾,春夏季和秋冬季拟合线斜率分别为1.00和0.94,R~2分别为0.91和0.95,均方根误差分别为46.15和12.45 W/m~2。该研究结果为实现PM模型在Venlo型温室环境的准确应用提供了参考。     

Evaluation of the effects of histone deacetylase inhibitors on cells from canine cancer cell lines

OBJECTIVE: To determine whether exposure of canine cancer cells to histone deacetylase (HDAC) inhibitors S(+)-N-hydroxy-4-(3-methyl-2-phenyl-butyrylamino)benzamide (OSU-HDAC42) or suberoylanilide hydroxamic acid (SAHA) results in increased histone acetylation and decreased cell viability and whether any changes in viability involve induction of apoptosis or alterations in progression of the cell cycle. Sample POPULATION: 9 canine cancer cell lines. PROCEDURES: Cells from 9 canine cancer cell lines were treated with dimethyl sulfoxide vehicle, OSU-HDAC42, or SAHA, then assays of cell viability were performed. Histone acetylation was assessed by use of western blot analysis. Apoptosis was assessed via ELISA to detect fragmentation of cytoplasmic nucleosomal DNA and western blot analysis to detect cleavage of caspase 3. Cell cycle analysis was performed by use of propidium iodide staining and flow cytometry. RESULTS-Concentrations of OSU-HDAC42 and SAHA required to achieve 50% inhibition of cell viability (IC(50)) were reached in cells of 6 and 4 canine cancer cell lines, respectively, and ranged from approximately 0.4 to 1.3 microM for OSU-HDAC42 and 0.6 to 4.8 microM for SAHA. Cells from T-cell lymphoma, mast cell tumor, osteosarcoma, and histiocytic sarcoma lines were most sensitive to HDAC inhibition, with IC(50)s of < 1 microM for OSU-HDAC42 and < 5 microM for SAHA. Induction of apoptosis was indicated via cleavage of caspase 3 and increases in cytoplasmic nucleosomes and the subG(1) cell population. CONCLUSIONS AND CLINICAL RELEVANCE: Micromolar concentrations of HDAC inhibitors OSU-HDAC42 and SAHA induced histone acetylation, cytotoxicity, and apoptosis in canine cancer cells. In general, OSU-HDAC42 was more potent than SAHA.