Genetic characterization of chicken anemia viruses newly isolated from diseased chicks in Japan in 2020

In this study, a total of nine chicken samples obtained from two broiler flocks in Oita and Tottori prefectures in 2020 were examined for Chicken anemia virus (CAV) infection. The samples were collected from clinically suspected flocks and diseased chickens. The CAV genome was detected in all nine samples tested by real-time PCR. Phylogenetic analyses and sequence comparisons of the full-length VP1 gene sequences indicated that all the Japanese CAV strains obtained in this study formed a similar cluster of genotype III and shared high nucleotide (99.62–100%) identity. The current Japanese CAV strains were closely related to Chinese CAV strains but not related to vaccine strains. One positive selection site of VP1 was detected among the Japanese CAV strains.     

Synthesis and antifungal activity of the proposed structure of a volatile compound isolated from the edible mushroom Hypsizygus marmoreus

We synthesized the proposed structure of an antifungal compound detected in the culture broth of the edible mushroom Hypsizygus marmoreus. Using the Evans aldol and Abiko–Masamune aldol reactions as the key steps, we synthesized all of the stereoisomers of the compound with high stereoselectivity. The GC retention times and the fragmentation patterns in the mass spectra of the synthesized isomers did not match those of the natural product. Therefore, this result may imply that it is necessary to reisolate the natural product and reconsider its structure. All of the synthesized isomers were found to exhibit antifungal activity against the phytopathogenic fungus Alternaria brassicicola. Due to their simple structures, the obtained isomers could be lead compounds for new pesticides.     

Ileal and total tract digestibility in local (Mong Cai) and exotic (Landrace × Yorkshire) piglets fed low and high-fibre diets, with or without enzyme supplementation

Ileal and total tract digestibility of low and high-fibre diets (100 and 200 g/kg neutral detergent fibre), with or without enzyme supplementation (mixture of cellulase, β-glucanase, α-amylase and protease) was determined in piglets of two breeds weaned at 30 days of age. The breeds were local (pure-breed Mong Cai, MC) and exotic (Landrace × Yorkshire, LY). The experimental diets were based on maize meal, soybean meal, fish meal, cassava residue meal, and rice bran. Cassava residue meal and rice bran were the main fibrous feeds in the high-fibre diet. The experiment was arranged according to a 2 × 2 × 2 factorial, completely randomized design with 4 replications, and lasted for 30 days. The coefficient of ileal apparent digestibility (CIAD) was measured by analyzing ileal digesta collected from piglets killed at 60 days of age. The coefficient of total tract apparent digestibility (CTTAD) was measured by analyzing faecal samples collected for 5 consecutive days immediately before the experiment finished. The CIAD and CTTAD of organic matter, crude protein, crude fibre, neutral detergent fibre, acid detergent fibre and amino acids in the high-fibre diet were lower than in the low-fibre diet (P < 0.01). The CIAD of nutrients and amino acids was similar (P > 0.05) between MC and LY, while the CTTAD of nutrients was higher for the MC than for LY (P < 0.05). Enzyme supplementation of the high-fibre diet improved daily gain and the digestibility of all dietary components at the ileum and in the total tract (P < 0.05), but there was no effect of enzyme supplementation of the low-fibre diet (P > 0.05).     

Presence of chlorogenic acid during in vitro maturation protects porcine oocytes from the negative effects of heat stress

Chlorogenic acid (CGA) is known to protect oocytes from oxidative stress. Here we investigated the effects of CGA on porcine oocyte maturation under heat stress and subsequent embryonic development after parthenogenetic activation. For in vitro maturation (IVM) at 41.0°C (hyperthermic condition), supplementation of the maturation medium with 50 μM CGA significantly improved the percentage of matured oocytes and reduced the rate of apoptosis relative to oocytes matured without CGA (p < .05). CGA treatment of oocytes during IVM under hyperthermia tended to increase (p < .1) percentage of blastocyst formation after parthenogenesis and significantly increased (p < .05) the total cell number per blastocyst relative to oocytes matured without CGA. For IVM at 38.5°C (isothermic condition), CGA significantly improved the rate of blastocyst development compared with oocytes matured without CGA (p < .05), but did not affect oocyte maturation, apoptosis rate or the number of cells per embryo. Omission of all antioxidants from the IVM medium significantly reduced the rate of oocyte maturation, but the rate was restored upon addition of CGA. These results demonstrate that CGA is a potent antioxidant that protects porcine oocytes from the negative effects of heat stress, thus reducing the frequency of apoptosis and improving the quality of embryos.     

Regulation of Oestrus ovis (Diptera: Oestridae) populations in previously exposed and naïve sheep

Larvae of Oestrus ovis (Insecta: Diptera: Oestridae) are common parasites of nasal and sinus cavities of sheep and goats. During larval development, a specific immune reaction is initiated by the host with a humoral local and systemic response and the recruitment of eosinophils and mast cells in the upper airways mucosae. Nevertheless, the roles of these responses in the regulation of O. ovis larvae populations in sheep are not yet known. The aim of this study was to compare the establishment and the development of larvae as well as some inflammatory or immune parameters between different groups of half-sibling sheep: (i) a primed group experimentally infected twice before a challenge infection, (ii and iii) two groups infected once only and previously treated with a long-lasting cortico?d before the challenge (one group) or not (the other group). A fourth group of non-infected animals was added in the experimental design. The larval establishment rate was 23% in the cortico?d treated group compared to about 10% in the two other infected groups. Moreover, the larval development appeared more rapid in the cortico?d treated group than in the two other infected groups suggesting that the inflammatory response is involved in the regulation of O. ovis populations. By contrast, no differences in the establishment rates were shown in the primed group compared to the na?ve group (without cortico?d treatment) despite evidence of higher eosinophilia, serum specific IgG, and immediate hypersensibility to excretory-secretory products of larvae. The specific lymphocyte proliferation was reduced in the primed group compared to the na?ve one suggesting that an immuno-suppression occurs following repetitive O. ovis infections.     

Molecular epidemiological characterization of poultry red mite, Dermanyssus gallinae,in Japan

Dermanyssus gallinae, the poultry red mite, is an obligatory blood-sucking ectoparasite. The genetic diversity of D. gallinae has been examined in some countries, but so far not in Asian countries. Here, we sequenced a part of the mitochondrial cytochrome oxidase subunit I (COI) and16S rRNA genes and nuclear internal transcribed spacers (ITS) region in 239 mite samples collected from 40 prefectures throughout Japan. The COI and 16S rRNA nucleotide sequences were classified into 28 and 26 haplotypes, respectively. In phylogenetic trees, the haplotypes clustered into 2 haplogroups corresponding to haplogroups A and B, which were previously reported. Haplogroups A and B were further subdivided into sub-haplogroups AJ1 and AJ2, and BJ1 and BJ2, respectively. In both trees, the sequences of haplotypes in AJ1 and BJ2 were relatively distant from those reported in other countries, while some sequences in AJ2 and BJ1 were identical to those in Europe. In addition, the ITS sequences were classified into two sequences, and both sequences were closely related to the sequences found in European countries. These findings indicate a possibility of international oversea transmission of D. gallinae.     

Assessment of biochemical and antioxidant diversities in a shallot germplasm collection from Vietnam and its surrounding countries

The shallot is considered an important genetic resource for Allium breeding programs because, compared to the bulb onion, the shallot contains higher levels of several functional chemical compounds. However, there may be differences in content, composition and beneficial activity among shallot landraces. This study was carried out to characterize the differences in phenolic, quercetin, sugar, S-alk(en)yl-l-cystein sulfoxide (ACSO), and saponin contents and antioxidant capacities of a shallot germplasm including 31 strains derived from different regions of Vietnam and six other countries. A wide variation was observed in the quantitative analyses of the chemical contents. Shallots with high contents of polyphenols, saponins, and quercetins were found in the south of Vietnam and other low-latitude countries. Meanwhile, those possessing fairly high ACSO and sugar contents were observed in the north of Vietnam. Qualitative analysis of saponins via thin layer chromatography did not show clear variation among shallot strains, but polymorphism was observed between the shallot and other Allium species, such as A. roylei. The principal component analysis could clearly discriminate shallot strains by their geographical origins. All shallot strains showed potent antioxidant activities in a DPPH assay. The highest antioxidant capacity was in the strains possessing relatively high contents of polyphenol, quercetin, and saponin. Significant correlations were found between antioxidant capacity (IC ₅₀ ^?1 ) and four groups of chemical compounds (polyphenols, quercetins, saponins, and ACSOs) (r = 0.40–0.59). A strong correlation was observed between IC ₅₀ ^?1 and quercetin contents (r = 0.59, p < 0.01). The six Fusarium-inoculated shallot strains seemed to be adequately resistant against disease, and the levels of resistance may be related to the saponin content in the bulb tissues.     

Structure of Fucoidan from Brown Seaweed Turbinaria ornata as Studied by Electrospray Ionization Mass Spectrometry (ESIMS) and Small Angle X-ray Scattering (SAXS) Techniques

The purpose of this study is to elucidate both the chemical and conformational structure of an unfractionated fucoidan extracted from brown seaweed Turbinaria ornata collected at Nha-trang bay, Vietnam. Electrospray ionization mass spectrometry (ESI-MS) was used for determining the chemical structure and small angle X-ray scattering (SAXS) provided conformational of the structure at the molecular level. The results showed that the fucoidan has a sulfate content of 25.6% and is mainly composed of fucose and galactose residues (Fuc:Gal ≈ 3:1). ESIMS analysis suggested that the fucoidan has a backbone of 3-linked α-l-Fucp residues with branches, →4)-Galp(1→ at C-4 of the fucan chain. Sulfate groups are attached mostly at C-2 and sometimes at C-4 of both fucose and galactose residues. A molecular model of the fucoidan was built based on obtained chemical structure and scattering curves estimated from molecular model and observed SAXS measurement were fitted. The results indicated that fucoidan under study has a rod-like bulky chain conformation.     

High-Tc Molecular-Based Magnets: Ferrimagnetic Mixed-Valence Chromium(III)-Chromium(II) Cyanides with Tc at 240 and 190 Kelvin

Molecular-based magnets with high magnetic-ordering temperatures, T(c), can be obtained by mild chemistry methods by focusing on the bimetallic and mixed-valence transition metal micro-cyanide of the Prussian blue family. A simple orbital model was used to predict the electronic structure of the metal ions required to achieve a high ordering temperature. The synthesis and magnetic properties of two compounds, [Cr(5)(CN)(12)].10H(2)O and Cs(0.75) [Cr(2.125)(CN)(6)].5H(2)O, which exhibited magnetic-ordering temperatures of 240 and 190 kelvin, respectively, are reported, together with the strategy for further work.     

Oral administration of Escherichia coli lipopolysaccharide enhances the immune system of striped catfish,Pangasianodon hypophthalmus (Sauvage)

Lipopolysaccharide (LPS), a component of Gram negative bacteria, was reported as important immunostimulant for fish. In this study, striped catfish were fed diets containing different Escherichia coli LPS concentrations (0%, 0.01% and 0.05%) for 2 weeks and then fed control feed (0% LPS) for 4 weeks. Plasma cortisol and glucose were rather low and did not differ significantly among treatments (P > 0.05). The respiratory burst activity, lysozyme, complement, total of antibody as well as mortality in fish challenged with Edwardsiella ictaluri were recorded every 2 weeks (W2, W4 and W6). The lysozyme activity significantly increased in fish treated with LPS (P < 0.05) in W2, W4 and W6. The highest values of respiratory burst activity were observed at week 4 in fish fed 0.01% LPS. There were significant differences in total of antibody between fish fed LPS (0.01%) and control in W2, W4. The challenge test with Edwardsiella ictaluri showed that fish fed 0.01% LPS had lower cumulative mortality (40%, 33% and 42%) compared with the fish fed 0.05% LPS (50%, 40% and 47%) and control fish (40%, 57% and 53%) in the three difference sampling times respectively. These results suggest that feed supplemented with 0.01% LPS could enhance immunity of striped catfish after 2 weeks of oral administration and fish could be protected against bacterial infection during the following 4 weeks.