A meta-analytical evaluation of the effects of high-salt water intake on beef cattle

Adequate drinking water is essential to maintain acceptable production levels in beef cattle operations. In the context of global climate change, the water scarcity forecasted for the future is a growing concern and it would determine an increase in the use of poorer quality water by the agricultural sector in many parts of the world. However, consumption of high-salt water by cattle has consequences often overlooked. A meta-analysis was carried out to assess the impact of utilizing high-salt water on dry matter (DMI) and water intake (WI), and performance in beef cattle. The dataset was collected from 25 studies, which were conducted between 1960 and 2020. Within the dataset, the water quality was divided into three categories according to the ratio of sulfates (SO4) or sodium chloride (NaCl) to total dissolved solids (TDS): 1) TDS = all studies included (average SO4:TDS = 0.4); 2) NaCl = considered studies in which water salinity was dominated by NaCl (average SO4:TDS = 0.1); and 3) SO₄ = considered studies in which water salinity was dominated by SO₄ (average SO₄:TDS = 0.8). Results showed that DMI and WI were negatively affected by high-salt water consumption, although the magnitude of the effect is dependent on the type of salt dissolved in the water. There was a quadratic effect (P < 0.01) for the WI vs. TDS, WI vs. NaCl, DMI vs. TDS, and DMI vs. NaCl, and a linear effect (P < 0.01) for WI vs. SO₄ and WI vs. SO₄. Average daily gain (ADG) and feed efficiency (FE) were quadratically (P < 0.01) affected by high-salt water, respectively. This study revealed significant negative effects of high-salt water drinking on beef cattle WI, DMI, and performance. However, the negative effects are exacerbated when cattle drink high-sulfate water when compared with high-chloride water. To the best of our knowledge, this is the first approach to evaluate animal response to high-salt water consumption and could be included in the development of future beef cattle models to account for the impact of water quality on intake and performance. In addition, this meta-analysis highlights the need for research on management strategies to mitigate the negative effects of high-salt water in cattle.     

Heavy Metal–Mineral Associations in Coeur d’Alene River Sediments: A Synchrotron-Based Analysis

Nearly a century of mining activities upstream have contaminated Lake Coeur d’Alene and its tributaries with Pb, Zn, and other heavy metals. Heavy metal concentrations in sediments of the Coeur d’Alene watershed have been shown to be inversely proportional to the sediment size fraction; thus, analysis on a very small scale is essential to determine the mobility and stability of heavy metals in this environment. Micron-scale synchrotron-based methods were used to determine the association of heavy metals with solid phases in sediments of the Coeur d’Alene River. Bulk X-ray diffraction (XRD), extended X-ray absorption fine structure spectroscopy, and synchrotron-based microfocused XRD combined with microfocused X-ray fluorescence mapping indicate the presence of crystalline Pb- and Zn-bearing mineral phases of dundasite [Pb₂Al₄(CO₃)₄(OH)₈·3H₂O], coronadite [PbMn₈O₁₆], stolzite [PbWO₄], mattheddleite [Pb₁₀(SiO₄)_3.5(SO₄)₂Cl₂], bindheimite [Pb₂Sb₂O₇], and smithsonite [ZnCO₃]. Likely phases for Zn and Pb adsorption were ferrihydrite, diaspore [AlO(OH)], manganite [Mn^(III)O(OH)], muscovite [KAl₂(Si₃Al)O₁₀(OH,F)₂], biotite [K(Fe,Mg)₃AlSi₃O₁₀(F,OH)₂], and montmorillonite [Na_0.3(Al,Mg)₂Si₄O₁₀(OH)₂·8H₂O]. The large predominance of Fe and Mn (hydr)oxides over other sorbent minerals suggests that the metal sorption behavior is dominated by these (hydr)oxide phases.     

Simulation study of the vegetation structure and function in eastern Siberian larch forests using the individual-based vegetation model SEIB-DGVM

The global ecosystem model SEIB-DGVM was adapted for an eastern Siberian larch forest through incorporation of empirical rules of allometry, allocation, and phenology developed for a larch stand at the Spasskaya-pad tower site, Yakutsk, Russia. After calibration, the model reconstructed post-fire successional patterns of forest structure and carbon cycling. It also reconstructed seasonal changes in carbon, water, and energy cycling in a mature larch forest. Sensitivity analysis showed that simulated functional properties of forest (LAI, NPP, carbon pools, and water runoff) are mainly determined by climatic environment, and population dynamic parameters (i.e., parameters for establishment and mortality) plays only minor role on them. Sensitivity analysis also showed that plant productivity and biomass were mainly limited by available water at Spasskaya-pad, where mean annual precipitation is only 257 mm. In the model, higher air temperature increases plant productivity via extension of growing season, and decreases plant productivity via causing drought and higher respiration. We found that the net effect is reduction of productivity, suggesting a possibility that global warming induces decrement of plant productivity in eastern Siberian larch forests.     

Antiplasmodial Activities of Homogentisic Acid Derivative Protein Kinase Inhibitors Isolated from a Vanuatu Marine Sponge Pseudoceratina sp.

As part of our search for new antimalarial drugs in South Pacific marine sponges, we have looked for inhibitors of Pfnek-1, a specific protein kinase of Plasmodium falciparum. On the basis of promising activity in a preliminary screening, the ethanolic crude extract of a new species of Pseudoceratina collected in Vanuatu was selected for further investigation. A bioassay-guided fractionation led to the isolation of a derivative of homogentisic acid [methyl (2,4-dibromo-3,6-dihydroxyphenyl)acetate, 4a] which inhibited Pfnek-1 with an IC₅₀ around 1.8 μM. This product was moderately active in vitro against a FcB1 P. falciparum strain (IC₅₀ = 12 μM). From the same sponge, we isolated three known compounds [11,19-dideoxyfistularin-3 (1), 11-deoxyfistularin-3 (2) and dibromo-verongiaquinol (3)] which were inactive against Pfnek-1. Synthesis and biological evaluation of some derivatives of 4a are reported.     

Modulation of leaf physiology by age and in response to abiotic constraints in young cuttings of two Populus deltoides × P. nigra genotypes

? It is of importance, when comparing physiological responses of leaves to environmental constraints among different genotypes, to take into account any effect related to leaf position and age within the canopy that might interfere with the response to the constraints.

? To document such effects, photosynthetic capacity and tolerance to heat and to oxidation were measured on leaves from the top to the bottom of three-month-old single-stem rooted cuttings of Populus deltoides × P. nigra genotypes, ‘Dorskamp’ and ‘Luisa_Avanzo’, thus taking into account a gradient of ages from youngest and still expanding (top) to oldest and fully expanded (bottom) leaves.

? All recorded traits were tightly linked to the age of the leaves. Photosynthetic capacity gradually increased during leaf expansion, in parallel with chlorophyll content and relative nitrogen allocation to RuBisCO and to bioenergetics. On the contrary, dark respiration gradually decreased during leaf expansion until a minimum value was reached at maturity. Compared to expanding leaves, young mature leaves were characterized by a lower sensitivity to heat and a higher one to oxidations generated by methyl-viologen.

? Leaf characteristics appeared to vary along the stem to a larger extent than between the two genotypes that display largely different productivities in plantations.

     

Effects of Age and Pretreatment of Tissue-Cultured Potato Plants on Subsequent Minituber Production

Potato (Solanum tuberosum L.) plantlets were conditioned in tissue culture to produce more minitubers when planted in a greenhouse. Tissue-cultured potato plantlets, varieties Coliban and Russet Burbank, were grown for 4, 10, or 12 weeks under three temperature regimes (22/18 °C, 16/10 °C, and 10/2 °C day/night) and a photoperiod of 16, 12, or 8 h in different stages of growth. Duration, temperature, and photoperiod of the in vitro period affected plantlet morphology and the total number of minitubers produced per plant in a greenhouse. Extending the growing period and introducing a hardening period with low temperatures (16/10 °C) during the in vitro production stage resulted in 97% more minitubers (4.94 vs 2.50 minitubers per plant for the control) in variety Coliban and up to 71% (6.50 vs 3.80 minitubers per plant for the control) in variety Russet Burbank. The total number of minitubers produced per plant did not change significantly for both varieties when a shorter photoperiod was used instead of the standard 16-h day during the growing period in vitro. Results presented in this experiment demonstrate that the number of minitubers can be substantially increased through the introduction of an induction period as an interstage between the in vitro stages of potato plantlet production and minituber production.     

The Marine-Derived Fungus Clonostachys rosea,Source of a Rare Conjugated 4-Me-6E,8E-hexadecadienoic Acid Reducing Viability of MCF-7 Breast Cancer Cells and Gene Expression of Lipogenic Enzymes

A marine-derived strain of Clonostachys rosea isolated from sediments of the river Loire estuary (France) was investigated for its high lipid production. The fungal strain was grown on six different culture media to explore lipid production changes. An original branched conjugated fatty acid, mainly present in triglycerides and mostly produced when grown on DCA (23% of total fatty acid composition). It was identified as 4-Me-6E,8E-hexadecadienoic on the basis of spectroscopic analyses. This fatty acid reduced viability of MCF-7 breast cancer cells in a dose dependent manner (up to 63%) at physiological free fatty acid human plasma concentration (100 μM). Reduction of gene expression of two lipogenic enzymes, the acetyl CoA carboxylase (ACC) and the fatty acid synthase (FAS) was evaluated to explore the mechanisms of action of 4-Me-6E,8E-16:2 acid. At 50 μM, 50% and 35% of mRNA gene expression inhibition were observed for ACC and FAS, respectively.     

Sex chromosomes and quantitative sex expression in monoecious hemp (Cannabis sativa L.)

Hemp (Cannabis sativa) has a highly variable sexual phenotype. In dioecious hemp, the sex is controlled by heteromorphic sex chromosomes according to an X-to-autosomes equilibrium. However, in monoecious hemp, the sex determinism remains widely unknown and has never been related to a quantitative approach of sex expression. The present paper aims to contribute to the comprehension of the sex determinism in monoecious hemp by assessing the genotypic variability of its sex expression and establishing its sex chromosomes. Five monoecious and one dioecious cultivars were grown in controlled conditions under several photoperiods. The monoecy degree of 194 monoecious plants was recorded at each node by a figure ranging from 0 (male flowers only) to 6 (female flowers only). The genome size of 55 plants was determined by flow cytometry. The DNA of 115 monoecious plants was screened with the male-associated marker MADC2. The monoecy degree varied significantly among monoecious cultivars from 3.36 ± 2.28 in ‘Uso 31’ to 5.70 ± 0.81 in the most feminised ‘Epsilon 68’. The variation of monoecy degree among cultivars remained consistent across trials despite a significant “cultivar × trial” interaction and partly agreed with their earliness. The genome size of monoecious plants (1.791 ± 0.017 pg) was not different from that of females (1.789 ± 0.019 pg) but significantly lower than that of males (1.835 ± 0.019 pg). MADC2 was absent from all monoecious plants. These results strongly support that cultivars of monoecious hemp have the XX constitution and that their sex expression has a genetic basis.     

Multiscale comparison of spatial patterns using two-dimensional cross-spectral analysis: application to a semi-arid (gapped) landscape

Spectral analysis allows the characterization of temporal (1D) or spatial (2D) patterns in terms of their scale (frequency) distribution. Cross-spectral analysis can also be used to conduct independent correlation analyses at different scales between two variables, even in the presence of a complex superposition of structures, such as structures that are shifted, have different scales or have different levels of anisotropy. These well-grounded approaches have rarely been applied to two-dimensional ecological datasets. In this contribution, we illustrate the potential of the method. We start by providing a basic methodological introduction, and we clarify some technical points concerning the computation of two-dimensional coherency and phase spectra and associated confidence intervals. First, we illustrate the method using a simple theoretical model. Next, we present a real world application: the case of patterned (gapped) vegetation in SW Niger. In this example, we investigate the functional relationships between topography and the spatial distribution of two shrub species, Combretum micranthum G. Don. and Guiera senegalensis J.F. Gmel. We show that both the global vegetation pattern and the distribution of C. micranthum are independent at all analyzable scales (i.e., from 10 to 50 m) from possible relief-induced determinisms. Additionally, the two dominant shrub species form distinct patches, thus suggesting separate niches.