Reduction in egg hatch ofArgas (Argas) reflexus (Fab.) (Acari,Argasidae) due to colchicine

The eggs ofArgas (Argas) reflexus (Fab.) were exposed to 0.05% colchicine on 9th, 15th or 23rd–25th days of embryonic development at 25°C and 30% RH. The eggs on the 15th and 23rd–25th days of development were the most sensitive to colchicine. In these experiments 6.9% and 9.4% embryos died, respectively. The largest number of disturbances of egg hatch (11.5%) were observed after exposure of the eggs to colchicine on 23rd–25th days of embryogenesis.     

Inhibitory factors ofArgas (Argas) reflexus (Fab.) (Acari,Argasidae) larvae development

The eggs ofArgas reflexus were splashed with the LiCl and Na₂Cr₂O₇ saturated solutions on the 2nd day after laying and were kept at 25° C and 30% RH.Both examined chemical compounds caused great disturbances in embryogenesis ofArgas reflexus. Under influence of Na₂Cr₂O₇ 24.8% eggs died. The LiCl solution appeared to be more harmful on larvae development. 21.8% dead eggs, 11.6% dead embryos, and 8.9% larvae hatched abnormally were observed in these experiments

---

Zusammenfassung Hemmende Faktoren bei der Embryonalentwicklung vonArgas (Argas) reflexus (Fab.) (Acari, Argasidae)Die Eier vonArgas reflexus wurden am 2. Tag der Embryonalentwicklung bei 25° C und 30% r. L. der. Wirkung gesättigter Lösungen von LiCl und Na₂Cr₂O₇ unterzogen.Beide chemischen Verbindungen verursachten große Störungen der Embryogenesis vonArgas reflexus. Unter dem Einfluß von Na₂Cr₂O₇ starben 24.8% der Eier ab. LiCl erwies sich als schädlicher für die Embryonalentwicklung dieser Zeckenart als Na₂Cr₂O₇.Bei den Experimenten mit LiCl wurden 21.8% Eier, 11.6% Embryos und 8.9% (abnormal geschlüpfte) Larven getötet.

---

---

With one table     

Evidence of plaggen soils in European North Russia (Arkhangelsk region)

To clarify whether a particular group of soils of Archangelsk region (European N Russia) with humus‐rich topsoils exceeding the plowing zone supports an anthropogenic formation, four exemplary profiles were investigated. The investigation sites are characterized by distinct elevated surfaces, and the soils show thick toplayers of up to 60 cm with enrichment of soil organic matter and artifacts like brick, charcoal, and peat fragments, all indicating an anthropogenic origin. Increased phytolith amounts and high P contents of up to 800 mg kg^–1 citric acid–soluble P and up to 1,400 mg kg^–1 total P in the top horizons support an anthropogenic influence. These properties are very similar to the Plagganthrepts of NW Europe. The same is true regarding the main management aims: increasing soil fertility and overcoming the need of bedding materials. Having the required depths of the anthropogenic topsoil, the properties of the soils of the Archangelsk region allow a classification as Agrozems (Russian classification), Plaggenesche (German classification), and Plagganthrepts (US taxonomy). Since the high base saturation of the topsoil excludes a designation as plaggic horizon, the topsoil has to be considered as terric horizon, which leads to a classification as Terric Anthrosol according to WRB.     

Structural and Immunochemical Studies of the Lipopolysaccharide from the Fish Pathogen,Aeromonas bestiarum Strain K296, Serotype O18

Chemical analyses and mass spectrometry were used to study the structure of the lipopolysaccharide (LPS) isolated from Aeromonas bestiarum strain K296, serotype O18. ESI-MS revealed that the most abundant A. bestiarum LPS glycoforms have a hexa-acylated or tetra-acylated lipid A with conserved architecture of the backbone, consisting of a 1,4′-bisphosphorylated β-(1→6)-linked d-GlcN disaccharide with an AraN residue as a non-stoichiometric substituent and a core oligosaccharide composed of Kdo₁Hep₆Hex₁HexN₁P₁. 1D and 2D NMR spectroscopy revealed that the O-specific polysaccharide (OPS) of A. bestiarum K296 consists of a branched tetrasaccharide repeating unit containing two 6-deoxy-l-talose (6dTalp), one Manp and one GalpNAc residues; thus, it is similar to that of the OPS of A. hydrophila AH-3 (serotype O34) in both the sugar composition and the glycosylation pattern. Moreover, 3-substituted 6dTalp was 2-O-acetylated and additional O-acetyl groups were identified at O-2 and O-4 (or O-3) positions of the terminal 6dTalp. Western blots with polyclonal rabbit sera showed that serotypes O18 and O34 share some epitopes in the LPS. The very weak reaction of the anti-O34 serum with the O-deacylated LPS of A. bestiarum K296 might have been due to the different O-acetylation pattern of the terminal 6dTalp. The latter suggestion was further confirmed by NMR.     

Rhamnolipids Increase the Phytotoxicity of Diesel Oil Towards Four Common Plant Species in a Terrestrial Environment

The study focused on assessing the influence of rhamnolipids on the phytotoxicity of diesel oil-contaminated soil samples. Tests evaluating the seed germination and growth inhibition of four terrestrial plant species (alfalfa, sorghum, mustard and cuckooflower) were carried out at different rhamnolipid concentrations (ranging from 0 to 1.200?mg/kg of wet soil). The experiments were performed in soil samples with a different diesel oil content (ranging from 0 to 25?ml/kg of wet soil). It was observed that the sole presence of rhamnolipids may be phytotoxic at various levels, which is especially notable for sorghum (the germination index decreased to 41?%). The addition of rhamnolipids to diesel oil-contaminated soil samples contributed to a significant increase of their phytotoxicity. The most toxic effect was observed after a rhamnolipid-supplemented diesel oil biodegradation, carried out with the use of a hydrocarbon-degrading bacteria consortium. The supplemention of rhamnolipids (600?mg/kg of wet soil) resulted in a decrease of seed germination of all studied plant species and an inhibition of microbial activity, which was measured by the 2,3,5-triphenyltetrazolium chloride tests. These findings indicate that the presence of rhamnolipids may considerably increase the phytotoxicity of diesel oil. Therefore, their use at high concentrations, during in situ bioremediation processes, should be avoided in a terrestrial environment.     

Effects of a novel missense polymorphism within the SIGLEC5 gene on fertility traits in Holstein‐Friesian cattle

The aim of the study was to find functional polymorphism within two exons of the SIGLEC5 (sialic acid‐binding Ig‐like lectin‐5) gene and to examine its effects on the production and fertility traits of cows and bulls. Two hundred seventytwo Holstein‐Friesian cows and 574 bulls were included in the study. Novel missense polymorphism (A > G) within exon 3 causing substitution of amino acid arginine by glutamate in position 260 of SIGLEC5 protein (R260Q) was identified by sequencing and digestion by restriction enzyme Msp I. Basic production and fertility traits of cows and estimated breeding values (EBV) of bulls were analysed. The study demonstrated a significant association of SIGLEC5 R260Q polymorphism with days open and calving interval in cows as well as with breeding value for calving interval in bulls. An opposite effect of SIGLEC5 alleles for production and fertility traits was observed: the allele G increased the breeding value for the protein yield, while the allele A increased the breeding value for the calving interval. The current study suggests the involvement of SIGLEC5 R260Q polymorphism in biological processes related to fertility traits. This finding can be applied as a biomarker for a genetic improvement programme in Holstein‐Friesian cattle.