The effect of elevated temperatures on food conversion efficiencies of Coccinella septempunctata and Harmonia axyridis young adults feeding on Sitobion avenae

Journal of Plant Diseases and Protection - An analysis of existing data gained in a set of climate chamber experiments was conducted to compare food conversion efficiencies of young Coccinella...     

Photosynthetic responses of spring barley varieties to different stand densities under field conditions

Abstract

Photosynthesis is affected by many factors on which plant productivity depends; however, little is known about the variation of spring barley photosynthetic characteristics under the influence of different stand densities. A 2-year field study was conducted to determine the photosynthetic rate (A), efficiency of excitation capture by open PSII reaction centres (F'v/F'm) and chlorophyll index (SPAD) response of various spring barley varieties to different stand densities (SDs) under field conditions. Three seed rates were used (200, 400 and 600 plants m^?2) and three varieties (Aura DS, Barke and Gustav). The measurements were made three times during the growing season. Varietal effect was significant on all indicators, the influence of the factors' interaction was significant on A, but SD influence was not significant. Varieties differed in tolerance to weather conditions. Maximum A was established for Gustav in wet year, but for Barke in dry year. The highest F'v/F'm was observed for Gustav under dry and warm conditions. The lowest F'v/F'm across varieties was for the lowest SD. The highest SPAD was observed for Gustav, the lowest for Aura DS. SPAD increased with decreasing SD. The correlation between the indicators and grain yield was positive. Meteorological conditions influenced the A data variation by 46.4–82.5%, 60.9–87.8% and 61.9–83.9% for the Aura DS, Barke and Gustav, respectively. Our research showed that under Central Lithuania's weather conditions the most effective photosynthetic process was recorded in the intensive variety Gustav, which is recommended to be grown at a medium crop density of 400 plants m^?2.     

Colour Flow Mapping examination: An useful screening test for the early diagnosis of ductus venosus patency in canine newborns

Ductus venosus (DV) closure plays a key role in hepatic circulation adaptation to postnatal metabolic function, and DV patency might develop a congenital portosystemic shunt (CPSS). The noninvasive Color Flow Mapping (CFM) examination, a validated method to diagnose CPSS in adult dogs, is routinely performed to assess DV closure after birth in humans. This study aimed to describe the feasibility of the ultrasonographic evaluation of the DV after birth and to determine its closure time in healthy Great Dane neonates. Patency of DV in serial Color Flow Mapping (CFM) examinations and bodyweight (BW) were recorded on Days 0‐3‐6‐9 in 24 neonates that were classified as having patent (PDV) or closed ductusvenosus (CDV) basing on CFM signal presence/absence. Since the 3rd day, DV diameter was recorded. Data were analysed by ANOVA (p < 0.05). All dogs resulted healthy 1 year later. The number of PDV and CDV puppies at birth was not different on Day 3 (24 and 0 vs. 22 and 2, PDV and CDV, respectively), whereas it resulted different on Days 6 (24 and 0 vs. 14 and 10) and 9 (24 and 0 vs. 0 and 24); on Day 3, it was different compared to Days 6 and 9; on Day 6, it was different from Day 9. Reduction of DV diameter resulted positively related to neonatal BW growth. The CFM evaluation of DV closure after birth in Great Dane puppies represents a feasible technique. Present results suggest the time of functional closure in normal neonates within 9 days after birth. Thus, CFM examination, as an early screening test for DV patency evaluation, performed 10 days after birth, may identify suspicious dogs at risk that would require further investigations. Further studies are needed to deepen the role of a delayed closure in low bodyweight and preterm puppies.     

Cauda equina compression syndrome (CECS): retrospective study of surgical treatment with partial dorsal laminectomy in 86 dogs with lumbosacral stenosis

We report our results of partial lumbosacral laminectomy for treatment of canine Cauda equina Compression Syndrome due to a lumbosacral stenosis. Opposite to conventional techniques of dorsal laminectomy, only widening of the Spatium interarcuale is performed. This is achieved by exstirpation of the Lig. flavum and partial dorsal laminectomy of the first sacral segment. The Proc. spinosi and integrity of facet joints are fully maintained by this technique. In 96.5% of 86 dogs treated with this method relief of dorsal pressure and permanent rapid regression of clinical symptoms was achieved. In two cases recurrence of clinical symptoms was observed during follow up and one case showed no improvement at all. In conclusion partial dorsal laminectomy is a minimal invasive technique for treatment of Cauda equina compression syndrome expressed by pain reaction accompanied by minor neurological deficits caused by lumbosacral stenosis. Maintained spinal stability allows short reconvalescence and the unrestricted use of dogs immediately post operation.     

Soil organic matter beyond molecular structure Part I: Macromolecular and supramolecular characteristics

This contribution reviews and discusses structural aspects of soil organic matter (SOM) and humic substances (HS) with special respect to the macromolecular and the supramolecular view. It can be concluded that (1) dissolved humic acids behave as supramolecular associations of relatively small molecules with an enormous flexibility of reaction of environmental conditions, (2) multivalent cations may increase the apparent molecular weight by the formation of coordinative crosslinks in dissolved and undissolved natural organic matter (NOM), (3) sorption nonlinearity in solid humic acids and SOM may be due to polymer properties of NOM, (4) sorbates affect sorbent characteristics of SOM, and (5) hysteresis and conditioning effects in SOM can up to now best be explained with the polymer analogy. A distinct polydispersivity of SOM over a wide range of molecular masses is to be assumed. The supramolecular and the macromolecular models were derived from humic acids with different composition and on the basis of different sample states. Although the supramolecular model has not explicitely been shown for unfractionated DOM, the combination of all discussed studies suggests supramolecular as well as macromolecular characteristics of NOM. Neither macromolecules nor small molecules can be fully excluded in solid and dissolved SOM. Microregions with different properties provide different types of sorption sites. SOM is suggested to be regarded as amorphous material. This point of view is not restricted to high molecular masses and may supplement our understanding of SOM by the model of physical aging.     

Mitotic Golgi partitioning is driven by the membrane-fissioning protein CtBP3/BARS

Organelle inheritance is an essential feature of all eukaryotic cells. As with other organelles, the Golgi complex partitions between daughter cells through the fission of its membranes into numerous tubulovesicular fragments. We found that the protein CtBP3/BARS (BARS) was responsible for driving the fission of Golgi membranes during mitosis in vivo. Moreover, by in vitro analysis, we identified two stages of this Golgi fragmentation process: disassembly of the Golgi stacks into a tubular network, and BARS-dependent fission of these tubules. Finally, this BARS-induced fission of Golgi membranes controlled the G2-to-prophase transition of the cell cycle, and hence cell division.     

Assessment of the Antimicrobial Activity of Algae Extracts on Bacteria Responsible of External Otitis

External otitis is a diffuse inflammation around the external auditory canal and auricle, which is often occurred by microbial infection. This disease is generally treated using antibiotics, but the frequent occurrence of antibiotic resistance requires the development of new antibiotic agents. In this context, unexplored bioactive natural candidates could be a chance for the production of targeted drugs provided with antimicrobial activity. In this paper, microbial pathogens were isolated from patients with external otitis using ear swabs for over one year, and the antimicrobial activity of the two methanol extracts from selected marine (Dunaliella salina) and freshwater (Pseudokirchneriella subcapitata) microalgae was tested on the isolated pathogens. Totally, 114 bacterial and 11 fungal strains were isolated, of which Staphylococcus spp. (28.8%) and Pseudomonas aeruginosa (P. aeruginosa) (24.8%) were the major pathogens. Only three Staphylococcus aureus (S. aureus) strains and 11 coagulase-negative Staphylococci showed resistance to methicillin. The two algal extracts showed interesting antimicrobial properties, which mostly inhibited the growth of isolated S. aureus, P. aeruginosa, Escherichia coli, and Klebsiella spp. with MICs range of 1.4 × 10⁹ to 2.2 × 10¹⁰ cells/mL. These results suggest that the two algae have potential as resources for the development of antimicrobial agents.     

Homocysteine measurement by an enzymatic method and potential role of homocysteine as a biomarker in dogs

In humans, homocysteine (Hcy) is employed to monitor renal, cardiovascular, and other diseases and their complications. The aim of the current study was to define the analytical performances of an enzymatic method not yet validated in dogs for measuring homocysteine, and to assess the possible clinical usefulness of Hcy measurement. Using conventional approaches, the analytical performances were investigated by assessing, imprecision, inaccuracy, and interference of hemoglobin, triglycerides, and bilirubin. The possible clinical usefulness of Hcy determination was assessed by comparing the results of healthy dogs (n = 8) with those of dogs with heart disease (n = 10), inflammation (n = 6), gastrointestinal disorders (n = 7), neoplasia (n = 8), renal failure (n = 4), trauma (n = 7), and other miscellaneous diseases (n = 6). Preliminary evaluation of this enzymatic method showed it to be precise at Hcy levels close to or higher than the values in dogs with renal or cardiac disorders that had the highest Hcy levels. By contrast, at low Hcy levels, which were recorded basically in control dogs, the method suffers from high imprecision. The sample of choice is serum. The use of icteric samples should be avoided, while hemoglobin and lipids have only a minor effect on Hcy measurement. In conclusion, the enzymatic method employed in the current study provides useful information in dogs and could be used to monitor cardiac and renal disorders, in which Hcy concentrations are elevated.     

Assessment of the optimal age for a preventive ultrasonographic screening of the uterine health in bitches

Studies about prevalence of uterine pathologies in bitches are scarce. Although correlation between age and uterine disorders was documented, the most suitable age for a preventive sonographic screening has not been proposed yet. Present study aimed to estimate the eligible age for an ultrasonographic screening of uterine abnormalities in dogs. Data regarding ultrasound examination and clinical records of non‐pregnant intact females were retrospectively analysed. The age of each bitch was expressed as age ratio (actual/maximum age expected for the respective breed). The cut‐off age ratio was determined by a ROC curve for overall uterine abnormalities. Frequencies of different abnormalities below and over the cut‐off derived from the ROC curve were calculated and statistically analysed by chi‐Square and OR. Prevalence of three categories of ultrasonographic findings was as follows: cystic endometrial hyperplasia (CEH) 18%; uterine collections (UC) 10.5%; masses (M) 1.3%. By the cut‐off age ratio (0.325), derived by ROC curve (AUC = 0.91; SP 84.23%; SE 79.2%; PPV 83.4%; NPV 80%), 228 cases were divided into two subgroups: bitches over (exposed group: n.83) and below cut‐off (control group: n.145). All abnormalities resulted more frequent in exposed group: OR was 24.96 (p < 0.0001: 71.1% over vs. 9% below cut‐off) for overall abnormalities; 13.68 (p < 0.0001: 40.9% vs. 4.8%) for CEH; 6.13 (p < 0.002: 21.7% vs. 4.1%) for UC; 12.65 (p = 0.09: 3.6% vs. 0%) for M. Cystic endometrial hyperplasia represents the most common finding in adult bitches, followed by UC. A preventive sonographic screening for uterine abnormalities should start from 33% of expected longevity to preventively select animals requiring further evaluations.