Novel Mode of Trisiloxane Application Reduces Spider Mite and Aphid Infestation of Fruiting Shrub and Tree Crops

Application of pesticides leads to contamination of the natural environment, which entails the necessity to seek solutions that use substances which do not pose ecological hazards. The presented investigations tested the efficacy of a preparation containing organomodified trisiloxane and a cross-linking agent (Siltac EC) to limit the number of two-spotted spider mite (Tetranychus urticae) on the leaves of raspberry (Rubus idaeus) and blackcurrant (Ribes nigrum), as well as the numbers of green apple aphid (Aphis pomi) on apple trees (Malus domestica). The high effectiveness (more than 90%) of Siltac against spider mite on raspberry and blackcurrant leaves was rapid and persisted at least by two- three weeks after spraying. There was observed an inhibition of pest developing (i.e. significant decrease of eggs and larvae). Similar effect occurred per an apple tree shoot and the number of living apple aphids was reduced by more than 93% in comparison to untreated trees. In all experiments, the effectiveness of Siltac was similar and usually longer lasting than control pesticides. Moreover, no phytotoxicity of the tested preparation was observed during the investigations. In conclusion, on the basis of the presented results it was found that Siltac EC could be a good alternative to the currently used plant protection chemicals

Preliminary evaluation of application of a 3-dimensional network structure of siloxanes Dergall preparation on chick embryo development and microbiological status of eggshells

The spatial network structure of Dergall is based on substances nontoxic to humans and the environment which, when applied on solid surfaces, creates a coating that reduces bacterial cell adhesion. The bacteriostatic properties of siloxanes are based on a purely physical action mechanism which excludes development of drug-resistant microorganisms. The aims of the present study were to 1) evaluate a Dergall layer formed on the eggshell surface regarding the potential harmful effects on the chick embryo; 2) evaluate antimicrobial activity and estimate the prolongation time of Dergall's potential antimicrobial activity. Dergall at a concentration of 0.6% formed a layer on the eggshell surface. In vitro testing of the potential harmful effects of Dergall by means of a hen embryo test of the chorioallantoic membrane showed no irritation reaction at a concentration of 3% and lower. The hatchability of the groups sprayed with a Dergall water solution with a concentration of 0 to 5% was 89.1 to 93.8% for fertilized eggs (P > 0.05) but decreased to 63.7% (P < 0.05) in the group sprayed with a 6% concentration of the solution. This phenomenon was caused by embryo mortality in the first week of incubation. At the concentration of 0.6%, Dergall exhibited strong antibacterial properties against bacteria such as Staphylococcus aureus, Escherichia coli, Shigella dysenteriae, Shigella flexneri, and Salmonella typhimurium. For Streptococcus pyogenes, the highest antibacterial activity of Dergall was reported in the concentrations of 100 and 50%. For Pseudomonas aeruginosa, no antibacterial activity of Dergall was generally observed, but in vivo testing showed a strong decrease of all gram-negative bacteria growth. Moreover, a prolonged antimicrobial effect lasting until 3 D after disinfection was observed, which makes Dergall a safe and efficient disinfectant

Identification of Secreted Exoproteome Fingerprints of Highly-Virulent and Non-Virulent Staphylococcus aureus Strains

Staphylococcus aureus is a commensal inhabitant of skin and mucous membranes in nose vestibule but also an important opportunistic pathogen of humans and livestock. The extracellular proteome as a whole constitutes its major virulence determinant; however, the involvement of particular proteins is still relatively poorly understood. In this study, we compared the extracellular proteomes of poultry-derived S. aureus strains exhibiting a virulent (VIR) and non-virulent (NVIR) phenotype in a chicken embryo experimental infection model with the aim to identify proteomic signatures associated with the particular phenotypes. Despite significant heterogeneity within the analyzed proteomes, we identified alpha-haemolysin and bifunctional autolysin as indicators of virulence, whereas glutamylendopeptidase production was characteristic for non-virulent strains.Staphopain C (StpC) was identified in both the VIR and NVIR proteomes and the latter fact contradicted previous findings suggesting its involvement in virulence. By supplementing NVIR, StpC-negative strains with StpC and comparing the virulence of parental and supplemented strains, we demonstrated that staphopain C alone does not affect staphylococcal virulence in a chicken embryo model

Effect of 50 Hz magnetic field on chicken embryo development and course of hatching

The effect of additional extremely low frequency (ELF) magnetic field (50 Hz) on the development of chick embryo was investigated. The experiment was carried out in three variants for induction values 15, 10 or 5 μT. Magnetic field (MF) in the experimental incubator was generated by a set of three Helmholtz coils. The following analyses were performed: embryopathological analysis; evaluation of the hatched chicks for quality; analysis of the course and synchronization of hatching Early embryo mortality in groups exposed to MF 10 and 15 μT compared to the control was higher by about 3 percentage points. Simultaneously, in these groups the hatching processes accelerated, but the quality of hatched chicks was much lower

Assessment of the antibacterial activity of chestnut (Castanea sativa) and cloves (Syzygium aromaticum) herbal extracts as an alternative to antibiotics use during post-hatching period of chicks

Bacterial infections of newly hatched chicks are the most common cause of their death in the initial period of rearing. These infections are always treated with antibiotics. The aim of the study was to investigate the antimicrobial activity of herbal extracts of chestnut (Castanea sativa) and clove (Syzygium aromaticum) against bacterial infections i.e. Escherichia coli, Enterococcus faecalis, Staphylococcus aureus, Klebsiella pneumonice in comparison to antibiotics. The results of the microbiological analyses showed that the Castanea sativa and Syzygium aromaticum extracts had a slighter antibacterial activity in comparison to antibiotics. The diameter of zone inhibition of the culture’s growth of gram-negative bacteria (i.e. Escherichia coli and Klebsiella pneumoniae) and gram-positive bacteria (i.e. Staphylococcus aureus and Enterococcus faecalis) was 6–13 mm for these extracts in comparison to 15–30 mm for antibiotics. However, some bacterial strains presented full resistance to the selected antibiotics, e.g., wild strains of Enterobacteriaceae to amoxicillin or Staphylococcus aureus and Enterococcus faecalis to florfenicol, colistin, and doxycycline. In the second experiment, the effect of the herbal extract mixture added into drinking water on the growth and mortality of chicken broiler during the first rearing week was investigated. There was found that the use of herbal extracts improved the chickens’ body weight (157.4 g; P ≤ 0.008) and decreased mortality rate (2.4%) compared to the control group (144.1 g and 3.9%, respectively) but not to the group treated with antibiotic (161.5 and 0.6% respectively; P ≤ 0.009). In summary, the use of herbal extracts as a nutritional supplement for poultry seems to have a positive effect on weight gain of young birds, and to some extent reduce mortality in the first week of rearing

Influence of ambient temperature on reproduction of the red-headed cricket (Gryllus assimilis)

Red-headed crickets were kept in glass insectariums equipped with drinkers, food containers and peat boxes for laying eggs. In the first stage of the experiment, the insects were divided into three groups, kept at 20°C, 25°C and 29°C, respectively. Three days after placing the crickets in the insectariums, the eggs were counted. In the second stage, the eggs (15 pcs.) were placed in boxes with peat in insectariums and exposed to the same temperatures as the females were kept at 20°C, 25°C and 29°C respectively, and the time in which the larvae hatch in each container was observed. It was found that the thermal conditions of the environment influence the number of eggs laid by female Gryllus assimilis and the length of the embryonic period in red-headed crickets. It is estimated that in the temperature range of 20–29°C, increasing the temperature by 1°C shortens the time needed to hatch the larvae from the eggs by 2 days

The Effect of α-Tocopherol on the Reduction of Inflammatory Processes and the Negative Effect of Acrylamide

Our research aimed to show acrylamide’s influence on inflammatory processes, the oxidative stress it causes in the cholinergic system, and the possibility of reducing inflammation via supplementation with α-tocopherol. For this purpose, an in ovo model was used where the embryos were exposed to acrylamide, α-tocopherol and a cocktail of these substances. After 48 h of exposure, we collected brain samples and performed biochemical assays to examine the effect of the chosen substances on oxidative stress (malondialdehyde-MDA and reduced glutathione-GSH) and acetylcholinesterase activity (AChE). The results showed that acrylamide decreased AChE activity in the examined brain samples by about 25% in comparison to the control group, and this effect was decreased by administering α-tocopherol. The concentration of malondialdehyde significantly increased in the group given acrylamide, while, in the group with α-tocopherol, the observed concentration was lower in comparison to the control group. Moreover, a decrease in glutathione concentration was observed after the administration of acrylamide; however, the protective effect of α-tocopherol was only slightly visible in this case. In conclusion, α-tocopherol minimizes the harmful effects of acrylamide on AchE, and it can minimize the concentration of MDA