Effect of a dietary essential oil mixture on performance of laying hens in the summer season

The experiment was conducted to evaluate the effects of dietary supplements of either an essential oil mixture (EOM) or a mannan oligosaccharide (MOS) as alternatives to an antibiotic feed additive (avilamycin) for layers kept under hot summer conditions. Four hundred and eighty 54-week old Nick-Brown hens were assigned to four dietary treatments. Each treatment consisted of four replications of 10 cages (three hens per cage). The treatment groups were: 1) Control: Basal diet without additive; 2) Basal diet plus antibiotic (10 mg avilamycin/kg feed); 3) Basal diet plus 1 g MOS/kg feed; 4) Basal diet plus 24 mg EOM/kg feed. Performance of laying hens was affected by dietary treatments. Dietary supplementation of EOM and MOS significantly increased egg production compared with control and antibiotic groups. There were no significant differences in feed consumption between treatments. The EOM significantly improved feed conversion ratio above that of the control group. Egg weights were significantly different between treatments. Laying hens consuming MOS produced significantly lower egg weights than the other groups, while egg weights in the EOM, antibiotic and control groups did not differ significantly. Cracked-broken egg rate was decreased by dietary addition of EOM, MOS and antibiotic compared with the control. Number of deaths among hens was significantly affected by dietary treatments with the number of deaths in the MOS treatment being significantly lower than in the other treatments. The performance of laying hens during the summer season could be maintained with inclusions of EOM and MOS in the diet. Keywords: Essential oils, mannan oligosaccharide, antibiotic, egg production, laying hen, summer seasonSouth African Journal of Animal Science Vol. 36 (4) 2006: pp. 215-22

Gas-particle partitioning and seasonal variation of polycyclic aromatic hydrocarbons in the atmosphere of Zonguldak, Turkey

Atmospheric concentrations and gas-particle partition coefficients were determined for polycyclic aromatic hydrocarbons (PAHs) in the atmosphere of Zonguldak, Turkey between May 2007 and April 2008. Total concentrations of PAHs ranged from 0.52ngm-3 to 636ngm-3 in the particle phase and from 5.60ngm-3 to 725ngm-3 in the gas phase. The annual mean concentrations of PAHs in the particle and gas phase were found to be 114ngm-3 and 184ngm-3, respectively. Significant seasonal variations of particle and gas phase PAH concentrations were observed with higher levels during cold period. The distribution of PAHs between the particle and gas phase was investigated and it was found that three ring PAHs were associated primarily with the gas phase, four ring PAHs were distributed almost equally between the two phases and five and six ring PAHs were mainly associated with the particle phase. Gas-particle partition coefficients (Kp) of PAHs have been calculated and correlated with their subcooled liquid vapor pressures (PL-). The slopes (mr) varied from -0.63 to -0.23 were far from the theoretical value (-1) due to the short distance between the sampling point and the emission sources. The relationships between temperature and gas phase partial pressures of PAHs were examined using the Clausius-Clapeyron equation and the obtained positive slopes indicated that PAH concentrations increased with decreasing air temperature as a result of high dominance of local emissions. © 2010 Elsevier B.V

Low density solvent-based dispersive liquid-liquid microextraction for the determination of synthetic antioxidants in beverages by high-performance liquid chromatography

A simple and efficient method was established for the determination of synthetic antioxidants in beverages by using dispersive liquid-liquid microextraction combined with high-performance liquid chromatography with ultraviolet detection. Butylated hydroxy toluene, butylated hydroxy anisole, and tert-butylhydroquinone were the antioxidants evaluated. Experimental parameters including extraction solvent, dispersive solvent, pH of sample solution, salt concentration, and extraction time were optimized. Under optimal conditions, the extraction recoveries ranged from 53 to 96%. Good linearity was observed by the square of correlation coefficients ranging from 0.9975 to 0.9997. The relative standard deviations ranged from 1.0 to 5.2% for all of the analytes. Limits of detection ranged from 0.85 to 2.73 ng mL-1. The method was successfully applied for determination of synthetic antioxidants in undiluted beverage samples with satisfactory recoveries. © 2013 Hasan Çabuk and Mustafa Köktürk

Particle-associated polycyclic aromatic hydrocarbons in the atmospheric environment of Zonguldak, Turkey

Airborne fine (PM2.5) and coarse (PM2.5-10) particulate matter was collected from January to December in 2007 in Zonguldak, Turkey using dichotomous Partisol 2025 sampler. Fourteen selected polycyclic aromatic hydrocarbons (PAHs) in particulate matter were determined simultaneously by high-performance liquid chromatography with fluorescence detection (HPLC-FL) and seasonal distributions were examined. The source identification of PAHs in airborne particulates was performed by principal component analysis (PCA) in combination with diagnostic ratios. The predominant PAHs determined in PM2.5 were pyrene, fluoranthene, benzo[a]anthracene, chrysene, benzo[b]fluoranthene and benzo[a]pyrene. The total concentrations of PAHs were up to 464.0 ng m- 3 in fine and 28.0 ng m- 3 in coarse fraction in winter, whereas in summer times were up to 22.9 and 3.0 ng m- 3 respectively. Approximately 93.3% of total PAHs concentration was determined in PM2.5 in winter and 84.0% in summer. The concentration levels of PAHs fluctuate significantly within a year with higher means and peak concentrations in the winter compared to that of summer times. Higher benzo(a)pyrene-equivalent (BaPE) concentrations of PAHs were obtained for PM2.5 especially in winter. The results obtained from PCA in combination with diagnostic ratios revealed that coal combustion and vehicle emissions were the major pollutant sources for both PM2.5 and PM2.5-10 associated PAHs in studied area. Two principal components for PM2.5 and three for PM2.5-10 were identified and these accounted for 89.4 and 85.2% of the total variance respectively. The emissions from coal combustion were estimated to be the main source of PAHs in the ambient air particulates with contributions of 80.8% of total variance for PM2.5 and 53.8% for PM2.5-10. © 2008 Elsevier B.V. All rights reserved.2007-13-2-3 2003 K121120The authors would like to thank the State Planning Organization of Turkey, (2003 K121120) and the Zonguldak Karaelmas University (2007-13-2-3) for the opportunity and support to carry out this research

Meteorological variations of PM2.5/PM10 concentrations and particle-associated polycyclic aromatic hydrocarbons in the atmospheric environment of Zonguldak, Turkey

Airborne particulate matter (PM2.5 and PM10) concentrations were measured in Zonguldak, Turkey from January to December 2007, using dichotomous Partisol 2025 sampler. Collected particulate matter was analyzed for 14 selected polycyclic aromatic hydrocarbons (PAHs) by high-performance liquid chromatography with fluorescence detection (HPLC-FL). The seasonal variations of PM2.5 and PM10 concentrations were investigated together with their relationships with meteorological parameters. The maximum daily concentrations of PM2.5 and PM10 reached 83.3 µg m-3 and 116.7 µg m-3 in winter, whereas in summer, they reached 32.4 µg m-3 and 66.7 µg m-3, respectively. Total concentration of PM10-associated PAHs reached 492.4 ng m-3 in winter and 26.0 ng m-3 in summer times. The multiple regression analysis was performed to predict total PM2.5- and PM10-associated PAHs and benzo(a)pyrene-equivalent (BaPE) concentrations with respect to meteorological parameters and particulate mass concentrations with the determination coefficients (R2) of 0.811, 0.805 and 0.778, respectively. The measured mean values of concentrations of total PM2.5- and PM10-associated PAHs were found to be 88.4 ng m-3 and 93.7 ng m-3 while their predicted mean values were found to be 92.5 ng m-3 and 98.2 ng m-3, respectively. In addition, observed and predicted mean concentration values of PM2.5-BaPE were found to be 14.1 ng m-3 and 14.6 ng m-3. The close annual mean concentrations of measured and predicted total particulate related PAHs imply that the models can be reliably used for future predictions of particulate related PAHs in urban atmospheres especially where fossil fuels are mainly used for heating. © 2009 Elsevier B.V. All rights reserved.2007-13-2-3 2003K121120The authors would like to thank the State Planning Organization of Turkey (2003K121120) and the Zonguldak Karaelmas University (2007-13-2-3) for the opportunity and support to carry out this research