Mesoscale spatial variability of ichthyoplankton in the Southwest Atlantic during the autumn–winter period

To gain a better understanding of the mechanisms underlying spatial heterogeneity in ichthyoplankton communities in the SW Atlantic, we examined for the first time the latitudinal and continental shelf–slope gradients in ichthyoplankton structure and oceanographic features in the Campos Basin during the relaxation phase of coastal upwellings (late autumn to early winter). This region, located on SE Brazil's continental margin, is the most productive offshore oil basin in the country and has ecological relevance owing to the existence of areas that experiences mesoscale (tens to hundreds of kilometers) processes (eddies, filaments, and upwelling) caused by the interaction of continental shelf and slope circulation with deep water masses. The present study collected a total of 3892 fish eggs and 10,030 larvae from 36 sampling stations, averaging 22 eggs per 100 m³ and 56 larvae per 100 m³. A total of 250 taxa (5 for fish eggs and 248 for larvae) were identified, encompassing 80 families and 145 genera. Species distribution exhibited a considerable degree of spatial variability, which was related mostly to hydrological characteristics. In general, greater densities were associated with higher nutrient concentrations areas. Through distance-based Redundancy Analysis, some discriminating species were found to associate with certain areas of the continental shelf characterized by colder temperatures. The ichthyoplankton distribution patterns suggested a potential influence from mesoscale oceanographic fronts, specifically those that induce upwelling of the cold and nutrient-rich South Atlantic Central Water. Nonetheless, the methodologies used in this study faced challenges in distinctly identifying these processes.     

Nutritional approaches to slow late finishing pig growth: implications on carcass composition and pork quality

Although pork producers typically aim to optimize growth rates, occasionally it is necessary to slow growth, such as when harvest facility capacity is limited. In finishing pigs, numerous dietary strategies can be used to slow growth so pigs are at optimal slaughter body weights when harvest facility capacity and/or access is restored. However, the impact of these diets on pork carcass quality is largely unknown. Thus, this study aimed to evaluate the efficacy of dietary strategies to slow growth in late finishing pigs and evaluate their effects on carcass composition and pork quality. Mixed-sex pigs (n = 897; 125 ± 2 kg BW) were randomly allotted across 48 pens and assigned to 1 of 6 dietary treatments (n = 8 pens/treatment): (1) Control diet representative of a typical finisher diet (CON); (2) diet containing 3% calcium chloride (CaCl₂); (3) diet containing 97% corn and no soybean meal (Corn); (4) diet deficient in isoleucine (LowIle); (5) diet containing 15% neutral detergent fiber (NDF) from soybean hulls (15% NDF); and (6) diet containing 20% NDF from soybean hulls (20% NDF). Over 42 d, pen body weights and feed disappearance were collected. Pigs were harvested in 3 groups (14, 28, and 42 d on feed) and carcass data collected. From the harvest group, 1 loin was collected from 120 randomly selected carcasses (20 loins/treatment) to evaluate pork quality traits. Overall, ADG was reduced in CaCl₂, Corn, and 20% NDF pigs compared with CON pigs (P < 0.001). However, ADFI was only reduced in CaCl₂ and 20% NDF pigs compared with CON (P < 0.001). Feed efficiency was reduced in CaCl₂ and Corn pigs compared with CON (P < 0.001). Hot carcass weights were reduced in CaCl₂ pigs at all harvest dates (P < 0.001) and were reduced in Corn and 20% NDF pigs at days 28 and 42 compared with CON pigs (P < 0.001). In general, CaCl₂ and 20% NDF diets resulted in leaner carcasses, whereas the Corn diet increased backfat by 42 d on test (P < 0.05). Loin pH was reduced and star probe increased in CaCl₂ pigs compared with CON pigs (P < 0.05); no treatments differed from CON pigs regarding drip loss, cook loss, color, firmness, or marbling (P ≥ 0.117). Overall, these data indicate that several dietary strategies can slow finishing pig growth without evidence of behavioral vices. However, changes to carcass composition and quality were also observed, indicating quality should be taken into consideration when choosing diets to slow growth.     

Large granular intestinal lymphosarcoma and leukemia in a dog

A rare, large granular lymphocyte (LGL) tumor causing a protein-losing enteropathy and thrombocytopenia was diagnosed in an Irish wolfhound. The case had an aggressive clinical course, like most LGL tumors in humans. Immunophenotyping suggested that the LGL tumor in this dog was derived from a natural-killer cell.     

Zinc exposure has differential effects on uptake and metabolism of sulfur and nitrogen in Chinese cabbage

Zinc (Zn) is a plant nutrient; however, at elevated levels it rapidly becomes phytotoxic. In order to obtain insight into the physiological background of its toxicity, the impact of elevated Zn²⁺ concentrations (1 to 10 μM) in the root environment on physiological functioning of Chinese cabbage was studied. Exposure of Chinese cabbage (Brassica pekinensis) to elevated Zn²⁺ concentrations (≥ 5 μM) in the root environment resulted in leaf chlorosis and decreased biomass production. The Zn concentrations of the root and shoot increased with the Zn²⁺ concentration up to 68‐fold and 14‐fold, respectively, at 10 μM compared to the control. The concentrations of the other mineral nutrients of the shoot were hardly affected by elevated Zn²⁺ exposure, although in the root both the Cu and Fe concentrations were increased at ≥ 5 µM, whereas the Mn concentration was decreased and the Ca concentration strongly decreased at 10 µM Zn²⁺. The uptake and metabolism of sulfur and nitrogen were differentially affected at ≥ 5 µM Zn²⁺. Zn²⁺ exposure resulted in an increase of sulfate uptake and the activity of the sulfate transporters in the root, and in enhanced total sulfur concentration of the shoot, which could be ascribed partially to an accumulation of sulfate. Moreover, Zn²⁺ exposure resulted in an up to 6.5‐fold increase in water‐soluble non‐protein thiol (and cysteine) concentration of the root. However, nitrate uptake by the root and the nitrate and total nitrogen concentrations of the shoot were decreased upon Zn²⁺ exposure, demonstrating the absence of a mutual regulation of the uptake and metabolism of sulfur and nitrogen at toxic Zn levels. Evidently, elevated Zn²⁺ concentrations in the root environment did not only disturb the uptake, distribution and assimilation of sulfate, it also affected the uptake and metabolism of nitrate in Chinese cabbage.     

Comparative forcing of Hydrangea macrophylla ‘Bailer’ as a florist's hydrangea

‘Bailer’ (Endless Summer™) is a new, pink- or blue-flowered hydrangea that flowers on new wood continuously throughout the growing season. It is also winter-hardy in northern, temperate climates (USDA Z4). Use of Endless Summer as a florist's potted hydrangea would provide consumers with a dual-use product (flowering potted plant, landscape shrub). The objectives were to determine if Endless Summer could be forced as a florist's hydrangea using two forcing regimes (immediate, standard), two soil pH regimes, and two pinching treatments. ‘Merritt Supreme Pink’ (pink), ‘Blue Danube’ (blue), and Endless Summer (blue, pink) were forced under immediate (no cold treatment, short- and long-day photoperiods) and standard (6 weeks cold, 4 °C to overcome dormancy) conditions. Since commercial liners were not yet available, cuttings of Endless Summer were used in the immediate forcing experiment. Days to visible flower bud, first color, full flower were recorded, as well as height, no. of branches, no. of flowers, and flower size. In the immediate forcing experiment, only Endless Summer produced flowers. Cultivars differed significantly (P < 0.001) for days to visible flower bud, days to first color, days to full flower, and height. The number of flowers and flower size were not significantly different among pink cultivars. In the standard forcing experiment, Endless Summer reached days to visible flower bud, days to first color, and days to full flower significantly earlier than either comparison, although it exhibited weaker stems and less intense flower pigmentation. Pinching (blue pH) had a significant effect on all traits except the days to full flower and flower size, although no pinching treatment was significant for pink pH. Photoperiod was significant only for the days to visible flower bud (pink pH), days to full flower (blue pH), and final height (blue pH). Further research is needed before Endless Summer can be grown as a dual-use florist's potted hydrangea with acceptable quality.     

Impact of sedimentation history for As distribution in Late Pleistocene-Holocene sediments in the Hetao Basin,China

Journal of Soils and Sediments - To understand the impact of geochemical sedimentation history for arsenic (As) distribution in the sediment profiles of the Hetao Basin, we (1) evaluated sediments...     

Evaluation of cell wall preparations for proteomics: a new procedure for purifying cell walls from Arabidopsis hypocotyls

Background  

The ultimate goal of proteomic analysis of a cell compartment should be the exhaustive identification of resident proteins; excluding proteins from other cell compartments. Reaching such a goal closely depends on the reliability of the isolation procedure for the cell compartment of interest. Plant cell walls possess specific difficulties: (i) the lack of a surrounding membrane may result in the loss of cell wall proteins (CWP) during the isolation procedure, (ii) polysaccharide networks of cellulose, hemicelluloses and pectins form potential traps for contaminants such as intracellular proteins. Several reported procedures to isolate cell walls for proteomic analyses led to the isolation of a high proportion (more than 50%) of predicted intracellular proteins. Since isolated cell walls should hold secreted proteins, one can imagine alternative procedures to prepare cell walls containing a lower proportion of contaminant proteins.     

A new microassay for antifeedants in<Emphasis Type="Italic"> Hylobius</Emphasis> pine weevils (Coleoptera)

A micro-feeding assay was developed for testing small amounts of synthetics and extracts as antifeedants for Hylobius pine weevils. We devised a simple setup consisting of 5×5-mm pieces of thin layer chromatography cellulose plates used in pairs for a bioassay involving choice. After application of 1.5 l solutions and evaporation of the solvent, each plate received a 5 l aliquot of 1 M sucrose as a feeding stimulant. The test period was 4 h at 25 °C with 6 days of starvation before the test, compared to just the 1 day sufficient for twig tests. Deprivation of water for 1 day at 65% RH before the test was critical because it increased feeding but not mortality. The combination of starvation and thirst reduced the relative variance (coefficient of variation) to below 50%. There was a good correlation of antifeedant activity in the microassay with the activity in a standard twig test. The microassay needs only several mg for a test series, whereas the twig test needs grams.