Molecular characteristics of fowl adenovirus strains detected in broiler chickens on diets without immunostimulant supplements.

Introduction: Outbreaks of fowl adenovirus (FAdV) infection in chicken flocks in Poland threaten birds' health and lives and are rising in frequency. The risk of these infections in immunocompromised poultry flocks with developed clinical symptoms was analysed through virus detection in broiler chicks and correlation of cases with the birds' immune strength. Material and Methods: Samples were analysed from four broiler farms with chicks from the same hatchery in Silesia, Poland where feeding regimes were different. A normal diet was provided to birds on the control farm; a normal diet and probiotic, prebiotic, vitamin and microelement supplementation was supplied on another farm; a normal diet and antibiotics on the third; and a normal diet and both forms of supplementation were given on the fourth farm. Amplification of the virus DNA in a PCR with hexon gene L1 loop hypervariable region 1-4 primers determined the molecular characteristics of isolates of adenovirus strains obtained from necropsy tissue samples. The amplicon sequences were analysed, the pair-wise distances were determined, the maximum likelihood estimate for the gamma parameter for site rates was produced, Tajima's D neutrality test was run and the relative synonymous codon usage and transition/transversion bias were calculated. Results: Two species and two serotypes of fowl adenovirus - MW353018-FAdV-1/A-L-liver and MW353019-FAdV-5/B-I-intestine - were isolated in three-week-old broiler chicks on the control farm. Conclusion: Supplementation of broiler chicken flocks with probiotics, prebiotics, vitamins and microelements may have a significant beneficial effect on immunity and can prevent virus infection. The studies provided new information on the molecular characteristics of adenovirus strains isolated from chicks with a low level of immunity.

Probiotic supplementation as an alternative to antibiotics in broiler chickens.

Introduction: The broiler chicken digestive tract microbiome maintains the bird's immunity. Its composition has been shown to be important not only for the immune system but also for the gastrointestinal function and productivity of broiler chickens. If the microbiome is populated by supplementation with Lactobacillus, Pediococcus and Saccharomyces spp. - microorganisms with probiotic properties and alternatives to antibiotics - the immune system is stimulated. The use of probiotic supplements in the broiler production cycle can boost bird immunity and prevent adenovirus infection. The resilience of broiler chickens in different feeding schemes including supplementation with these microorganisms was assessed. Material and Methods: Four groups of Ross 308 chickens vaccinated on the standard scheme were investigated over 42 days. Group P received probiotics, prebiotics and vitamins; group AO received antibiotics; group P&AO received probiotics, prebiotics, vitamins and antibiotics; and the control group C received none of these. The birds' immunocompetence against common viral poultry pathogens and their immune response to an experimental challenge with a field strain of infectious bronchitis was evaluated by ELISA and production parameters were recorded. Results: Mortality was only observed in the control group and was 10%. All birds from the P, P&AO and AO groups responded to the challenge as would be expected of appropriately immunised chickens. Conclusion: The obtained results indicated that supplementation with synbiotic products and vitamins can enhance broiler chicken immunity and result in better production parameters.

Assessment of changes in blood lactate levels in children and adolescents with type 1 diabetes during a football tournament (GoalDiab Study).

INTRODUCTION: Monitoring physical activity is a very important issue, especially in type 1 diabetes. One of the parameters assessing the intensity of exercise is the concentration of lactate in the blood. Aim of the study We assessed the intensity of PE and changes in lactate levels in children and adolescents with type 1 diabetes (T1D) during a football tournament. MATERIAL AND METHODS: We enrolled 141 participants, the results of 70 of whom were analyzed, playing in two age categories: 10-13 and 14-17 years. Lactate levels were measured in the capillary blood before and after matches. Blood lactate of 4 mmol/l (Onset Blood Lactate Accumulation OBLA) was used as parameter indicating the prevalence of anaerobic metabolic changes. RESULTS: The median lactate level was 1.8 mmol/l before and 4.4 mmol/l after matches (p < 0.001). The increase in lactate levels was higher in the older age category (4.3 vs. 1.8, p = 0.001) and was independent on gender (3.2 vs. 2.1, p = 0.597), personal insulin pump vs insulin pen use (3.0 vs. 1.5, p = 0.145) or training in a sports club (1.4 vs. 3.0, p = 0.084). A positive correlation was noted between increased lactate levels and age (Rs = 0.253, p = 0.034). 61% of the participants exceeded lactate levels ≥ 4 mmol/l. In univariate logistic regression analysis age was a significantly associated with lactate level ≥ 4 mmol/l [OR = 1.45 (1.08-1.95)] independent of HbA1c, gender, treatment method and training in a sports club. CONCLUSIONS: PE intensity levels during football matches were found to be mixed aerobic-anaerobic. Increases in lactate levels were greater in the older subjects independently on the assessed factors.

Experimental demonstration of the rotational frequency shift in a molecular system.

The frequency shift expected to occur analogously to the Doppler effect when an emitting quantum system is forced to rotate [Phys. Rev. Lett. 78, 2539 (1997)] has been detected for the first time, and verified quantitatively. The experimental conditions were chosen such that the most general case was realized where perturbation theory is not applicable. Circularly polarized visible laser light tuned to a rovibronic transition, and a rotating radio-frequency electric field were applied to the strongly polar molecule H2CS in a gaseous sample.

Optical absorption spectrum of gold atoms deposited on SiO(2) from cavity ringdown spectroscopy.

The optical properties of gold atoms supported on amorphous silica (alpha-SiO2) were studied experimentally and theoretically in the visible range. Samples were prepared in situ by depositing Au atoms at low coverages (5 x 10(12) cm(-2)) in UHV, and the optical absorption spectra were recorded by cavity ringdown spectroscopy. The atomic absorption bands can be attributed to gold atoms trapped at [triple bond] Si-O(.-) and [triple bond]Si-O(-) defect sites. The absence of optical transitions typical for Au(2) shows that the atoms are efficiently anchored at these defect sites, preventing diffusion and aggregation. Furthermore, these experimental results reveal that it is now possible to study optical properties of well-defined nanostructures at surface coverages as low as 5 x 10(11) cm(-2).

Gold atoms and dimers on amorphous SiO(2): calculation of optical properties and cavity ringdown spectroscopy measurements.

We report on the optical absorption spectra of gold atoms and dimers deposited on amorphous silica in size-selected fashion. Experimental spectra were obtained by cavity ringdown spectroscopy. Issues on soft-landing, fragmentation, and thermal diffusion are discussed on the basis of the experimental results. In parallel, cluster and periodic supercell density functional theory (DFT) calculations were performed to model atoms and dimers trapped on various defect sites of amorphous silica. Optically allowed electronic transitions were calculated, and comparisons with the experimental spectra show that silicon dangling bonds [[triple bond]Si(.-)], nonbridging oxygen [[triple bond]Si-O(.-)], and the silanolate group [[triple bond]Si-O(-)] act as trapping centers for the gold particles. The results are not only important for understanding the chemical bonding of atoms and clusters on oxide surfaces, but they will also be of fundamental interest for photochemical studies of size-selected clusters on surfaces.