Optimization of in vitro embryo production and zygote vitrification for the indigenous Vietnamese Ban pig: The effects of different in vitro oocyte maturation systems

The Vietnamese Ban pig is a precious genetic resource that needs to be preserved. In vitro embryo production from in vitro matured (IVM) oocytes is an important tool for the utilization of cryopreserved porcine sperm. The aim of this study was to compare two media for the IVM of Ban pig oocytes. Immature oocytes were subjected to IVM either in a non‐defined (TCM‐199 + pig follicular fluid) or in a defined base medium (POM + epidermal growth factor). At the end of IVM, the oocytes were in vitro fertilized (IVF) with frozen Ban sperm. Ten hours after IVF, the oocytes were either subjected to orcein staining to check fertilization and maturation status or cultured in vitro for 7 days. There was no difference between the two IVM media in terms of percentages of oocyte maturation and blastocyst production. However, the percentage of male pronuclear formation after IVF and the total cell numbers in blastocysts were higher with the defined system. Zygotes obtained by the two IVM systems survived vitrification at similar rates. In conclusion, the two IVM systems were both effective for the production of Ban pig embryos; however, better embryo quality was achieved with the defined one.     

Association between the body weight of growing pigs and the functional capacity of their gut microbiota

Gastrointestinal microbiota impact host's biological activities, including digestion of indigestible feed components, energy harvest, and immunity. In this study, fecal microbiota of high body weight (HW) and low body weight (LW) growing pigs at 103 days of age were compared. Principal coordinates analysis separated the HW and LW groups into two clusters, indicating their potential differences between microbial community composition. Although the abundances of two major phyla, Firmicutes and Bacteroidetes, did not significantly differ between the HW and LW groups, some genera showed significant differences. Among them, Peptococcus and Eubacterium exhibited strong positive correlations with body weight (BW) and average daily gain (ADG) (Rho > 0.40), whereas Treponema, Desulfovibrio, Parabacteroides, and Ruminococcaceae_unclassified exhibited strong negative correlations with BW and ADG (Rho < ?0.40). Based on these results, the structure of intestinal microbiota may affect growth traits in pigs through host–microbe interactions. Further in‐depth studies will provide insights into how best to reshape host–microbe interactions in pigs and other animals as well.     

Evaluation of the effects of transplanting date shifts and drainage outlet raising management practices in paddy farming regions under future climates using coupled APEX-Paddy and SWAT models

Paddy and Water Environment - Predicting adaptation and the response of agricultural water resources to climate change is a challenging. As changes in future climate will change agricultural...     

Diversity and evolution of major Panax species revealed by scanning the entire chloroplast intergenic spacer sequences

Ginseng is an important medicinal plant, but almost no genomic information is known for it. For the primary step to understand the Panax genome, we inspected the chloroplast genome sequence diversity and used that to infer the evolution of Panax species using them. We inspected a total of 101 intergenic spacers (IGS) covering 44,563 bp (96.8 % of the total IGS) from four Panax species. Diversity was inspected by three steps: gel electrophoresis, high resolution melting (HRM) analysis, and further confirmation by sequencing. Even though low levels of InDel polymorphism were detected by gel electrophoresis, high levels of reproducible polymorphisms were identified by HRM analysis. Sequencing of the HRM-polymorphic spaces and pair-wise multiple sequence alignments revealed up to 247 sequence variations between species. We have identified 62 IGS showing polymorphism between species. Among them, the trnE-trnT, trnT-psbD, ndhF-rpl32, and rpl14-rpl16 spaces are more informative for studying the diversity of Panax relatives. Phylogenetic analysis and molecular evolution studies revealed that P. notoginseng is most diverged from the other Panax species, with a nucleotide substitution rate of 0.0039. P. quinquefolius shows a close relationship with P. ginseng and P. japonicus, with a nucleotide substitution rate of 0.0009. Meanwhile, no sequence variation was detected between P. ginseng and P. japonicus. Calculation of molecular clocks revealed that P. notoginseng diverged more than 1.30 million years ago from the other Panax species and then, P. quinquefolius diverged from P. ginseng by migration in the American continent more than 0.29 million years ago.     

Oxidation and fate of chromium in soils

Abstract

The ammonia electrode method was used to characterize soil organic nitrogen. Amide-N, α-amino-N and hexosamine-N were estimated by measuring the ammonium-N derived from each organic-N with an ammonia electrode after hydrolysis of standard compounds followed by certain treatments. Each organic-N was recovered quantitatively from each standard compound in the presence and absence of soil. Twenty soil samples were analyzed for the above forms of organic nitrogen by both the distillation and electrode methods. The results obtained by the ammonia electrode method for each form of organic nitrogen agreed closely with those obtained by the distillation method. The electrode method was preferred for subsequent soil studies since it is simple and sensitive.     

Amendment of drilling fluid-affected soils with calcium salts

Land disposal of waste drilling fluid is an environmental concern because of the high salt content and the presence of potential toxic elements. A water-based drilling fluid was tested in a laboratory column study to determine the feasibility of leaching excessive salt without mobilizing chromium (Cr). The drilling fluid-affected two Alfisols with similar mineralogy, acidity, and texture were treated with gypsum (CaSO₄ · 2H₂O), calcium carbonate (CaCO₃), or calcium phosphate (CaHPO₄) (0 to 2% of weight). The electrical conductivity (EC) increased and the sodium adsorption ratio (SAR) decreased with increasing Ca-salt concentration. The pH did not vary significantly with the changes in the concentrations of gypsum and calcium phosphate. The pH of the mixtures increased in proportion to the concentration of added calcium carbonate. The hydraulic conductivity increased and the mobility of the soil particles decreased with increasing Ca-salt concentration. The Cr mobility decreased by gypsum and CaCO₃ treatments but it increased by calcium phosphate treatment. The soil with a higher content of organic matter and cation exchange capacity (CEC) showed a higher hydraulic conductivity and lower Cr mobility than the other soils at the same levels of the treatment. The results of this study suggest that the amendment of drilling fluid-affected soils with CaCO₃ and gypsum can enhance the leaching of excessive salt and reduce the Cr mobility. Among loamy soil, those with a higher CEC and organic matter content are more suitable for land disposal of drilling fluid.     

Removal of Metaldehyde Through Photocatalytic Reactions Using Nano-Sized Zinc Oxide Composites

In this study, we have reported the synthesis of new amino-substituted p-tert-butylcalix[4]arene (3) and its application for the removal of two carcinogenic azo dyes, i.e., Chicago Sky Blue (CSB) and Tropaeolin 000 (TP) from aqueous environment. The newly synthesized calix–ligand 3 is characterized by FT-IR and ¹H NMR spectroscopy as well as elemental analysis. The extraction efficiency of newly calix–ligand 3 for CSB and TP dyes from aqueous media was evaluated through liquid–liquid extraction experiments. The newly synthesized calix–ligand 3 showed outstanding extraction percentage and maximum percent extraction, i.e., 97 and 96 % of CSB and TP dyes was achieved at pH 9, respectively. During the extraction process, effect of various parameters was monitored and found that extraction is highly dependent on pH and salinity. Moreover, cyclic structure, cavity size, functional groups of the calixarene derivative, hydrophobicity, and the ionic property of guest molecules also affect the extraction efficiency. The comparative data prop up calix–ligand 3 as an effective extractant for both CSB and TP dyes.     

The uptake,distribution, and accumulation of 15N-labelled ammonium and nitrate nitrogen top-dressed at different growth stages of rice

A pot experiment with soil culture was carried out to trace ¹⁵N-labelled nitrogen top-dressed at different growth stages of rice. The study involves the use of a modified vacuum system for determining total nitrogen by gu volumetric measurement, and the N₂ gas sampled in the discharge tube was analysed for nitrogen-15 by the optical spectrographic technique.

The plants took up more nitrogen from (¹⁵NH₄)₂SO₄ than from Na¹⁵NO₃, irrespective of the stage of dressing, and the uptake of both forms was much higher when the planta were top-dressed at the young panicle formation stage as compared with the later dressings. At full maturity the plants had the highest accumulation of labelled nitrogen from both ammonium and nitrate sources when they are top-dressed at the young panicle formation stage. More than 80% ot the labelled nitrogen taken up by the plants waa distributed in the brown rice and this trend was more remarkable when top-dressing was carried out at the milk stage. The distribution patterns of ammonium and nitrate nitrogen were similar in brown rice but differed in leaves and stem.

Nitrogen transported from other parts to the panicle was utilized for the formation ot the husk until the booting stage, and then for brown rice development. With the completeness of husk formation, at the milk stage, nitrogen transported to the grain might have been utilized for brown rice development more rapidly. In the brown rice, nitrogen from ammonium was translocated maximally to the inner part of the endosperm from dressing at the booting stage, and to the embryo from that at the milk stage, whereas that from nitrate was translocated maximally to the embryo from the dressings at both stages.