Recruitment of the threatened mussel Margaritifera margaritifera in relation to mussel population size,mussel density and host density

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Effects of Pressurized Low Polarity Water Extraction Parameters on Antioxidant Properties and Composition of Cow Cockle Seed Extracts

Antioxidant activity of pressurized low polarity water (PLPW) extracts of cow cockle seed and extraction residues were determined using DPPH, ABTS, and FRAP assays. The effect of extraction conditions (temperature (125, 150 and 175 °C) and time) on the antioxidant activity and the relationship amongst the antioxidant activity and extract composition (total phenolics and saponin content) were determined. The antioxidant activity of PLPW extracts increased with extraction temperature. Increasing activity with time was also observed at 175 °C. PLPW extraction residues had the highest activity suggesting antioxidant compounds were not completely extracted by PLPW. Antioxidant activity correlated well with total phenolics content of samples (R ² ≥ 0.94), however no correlation was observed with the saponin content. A strong correlation was observed between the antioxidant activity values obtained using different methods (R ² ≥ 0.94). These results point to the potential of PLPW extraction as a method to modify the activity of biological materials for the production of customized extracts.     

Differential gene expression of CYP3A isoforms in equine liver and intestines

Tydén, E., Löfgren, M., Pegolo, S., Capolongo, F., Tjälve, H., Larsson, P. Differential gene expression of CYP3A isoforms in equine liver and intestines. J. vet. Pharmacol. Therap.  35 , 588–595. Recently, seven CYP3A isoforms – CYP3A89, CYP3A93, CYP3A94, CYP3A95, CYP3A96, CYP3A97 and CYP129 – have been isolated from the horse genome. In this study, we have examined the hepatic and intestinal gene expression of these CYP3A isoforms using TaqMan probes. We have also studied the enzyme activity using luciferin‐isopropyl acetal (LIPA) as a substrate. The results show a differential gene expression of the CYP3A isoforms in the liver and intestines in horses. In the liver, CYP3A89, CYP3A94, CYP3A96 and CYP3A97 were highly expressed, while in the intestine there were only two dominating isoforms, CYP3A93 and CYP3A96. The isoform CYP3A129 was not detected in the liver or the intestine, although this gene consists of a complete set of exons and should therefore code for a functional protein. It is possible that this gene is expressed in tissues other than the liver and intestines. In the intestine, both CYP3A96 and CYP3A93 showed the highest gene expression in the duodenum and the proximal parts of the jejunum. This correlated with a high protein expression in these tissues. Studies of the enzyme activity showed the same K_m for the LIPA substrate in the liver and the intestine, while the maximum velocity (V_max) in the liver was higher than in the intestine. Our finding of a differential gene expression of the CYP3A isoforms in the liver and the intestines contributes to a better understanding of drug metabolism in horses.     

The effect of different nitrogen levels on yield and quality of stevia (Stevia rebaudiana bert.)

In the present work, the efficiency of different nitrogen doses (0, 50, 100, 150, and 200 kg ha^?1) on growth, yield, and quality of stevia (Stevia rebaudiana Bert.) was investigated in 2011–2013. The study was conducted in Antalya located in the Mediterranean Region of Turkey. Terra rossa type soil (LVx, FAO) characteristics of the experimental field were clay loam, with high amounts of lime (33,9%) and slightly alkaline (pH 7.7). The experiment was carried out in randomized block design with four replications. All the results were summarized as mean of three years. The highest fresh and dry biomass yields (26.75 t ha^?1 and 7.5 ha^?1, respectively) were obtained from 150 kg ha^?1 N dose and followed by 100 kg ha^?1 N dose (26.29 t ha^?1 and 7.24 ha^?1, respectively). Whereas the highest fresh and dry leaf yields (13.27 t ha^?1 and 3.82 t ha^?1, respectively) were realized in 100 kg ha^?1 N dose. Actually, all nitrogen doses gave higher biomass and leaf yields compared to the control. On the hand, major steviol glycosides (stevioside and rebaudioside A) in the leaf were not influenced by nitrogen levels. In conclusion, 100 kg ha^?1 N dose was found to be suitable for cultivation of stevia under field conditions.     

Alleviation of salt stress by increasing potassium sulphate doses in four medicinal and aromatic plants

In this study, the effects of potassium doses (control, 150, 300 and 450?mg K₂SO₄ kg^?1) and salt stress (control, 100?mM NaCl) on the yield and some element content of four medicinal and aromatic (Coriandrum sativum, Anethum graveolens, Ocimum basilicum and Foeniculum vulgare) plants were investigated in climate chamber. Both salinity and K fertiliser levels affected the fresh and dry weight of all evaluated plants. Anethum graveolens, Ocimum basilicum species are more sensitive to salinity, particularly at the vegetative productive stages. The highest fresh and dry weights of leaves, stems, roots and herb in Coriandrum sativum and Foeniculum vulgare species was observed in 300?mg?kg^?1 fertiliser applications. In general, there was a relatively consistent and positive correlation between root element content and aerial parts element content. The result of the present study showed that NaCl treatment caused an increase in Na⁺ concentration, and a decrease in K⁺ and Ca⁺² concentration in Coriandrum sativum, Anethum graveolens, Ocimum basilicum and Foeniculum vulgare. There was an interaction between K₂SO₄ application and salinity effects on Na⁺ concentration in the all evaluated plants. Given the experimental results, especially Foeniculum vulgare and Coriandrum sativum species were the most resistant to salt stress.     

Heavy loads of parasitic freshwater pearl mussel (Margaritifera margaritifera L.) larvae impair foraging,activity and dominance performance in juvenile brown trout (Salmo trutta L.)

The life cycle of the endangered freshwater pearl mussel (Margaritifera margaritifera) includes a parasitic larval phase (glochidia) on the gills of a salmonid host. Glochidia encystment has been shown to affect both swimming ability and prey capture success of brown trout (Salmo trutta), which suggests possible fitness consequences for host fish. To further investigate the relationship between glochidia encystment and behavioural parameters in brown trout, pairs (n = 14) of wild‐caught trout (infested vs. uninfested) were allowed to drift feed in large stream aquaria and foraging success, activity, agonistic behaviour and fish coloration were observed. No differences were found between infested and uninfested fish except for in coloration, where infested fish were significantly darker than uninfested fish. Glochidia load per fish varied from one to several hundred glochidia, however, and high loads had significant effects on foraging, activity and behaviour. Trout with high glochidia loads captured less prey, were less active and showed more subordinate behaviour than did fish with lower loads. Heavy glochidia loads therefore may negatively influence host fitness due to reduced competitive ability. These findings have implications not only for management of mussel populations in the streams, but also for captive breeding programmes which perhaps should avoid high infestation rates. Thus, low levels of infestation on host fish which do not affect trout behaviour but maintains mussel populations may be optimal in these cases.     

Effects of enhancing vitamin D status by 25-hydroxycholecalciferol supplementation,alone or in combination with calcium and phosphorus,on sternum mineralisation and breast meat quality in broilers

1. The aim of the present study was to examine the effects of improving vitamin D status in broiler diets by supplementary 25-hydroxycholecalciferol (25OHD₃), alone or in combination with calcium (Ca) and available phosphorus (aP), on live performance, sternum mineralisation and breast meat quality in broilers.

2. A total of 936 1-d-old Ross 308 broilers were used in the study. After gender determination at the hatchery, chicks from each sex were randomly distributed into three dietary treatments. The following dietary treatments were used in the experiment from hatch to 38 d: (1) A control diet formulated to meet all of the nutrient requirements of broiler chicks according to the management guide; (2) The control diet supplemented with 18.7–15.0 µg/kg of 25OHD₃; and (3) The control diet supplemented with 18.7–15.0 µg/kg of 25OHD₃ plus Ca + aP.

3. Improvement in vitamin D status by 25OHD₃ supplementation, alone or in combination with Ca and aP, had no effect on body weight and feed conversion ratio of broilers.

4. The serum 25OHD₃ concentration significantly increased with 25OHD₃ and 25OHD₃ plus Ca + aP supplementation (P < 0.05), whereas the ionised Ca and Mg concentrations remained unchanged.

5. Sternum absolute weight, ash content and the concentrations of Ca and P significantly increased (P < 0.01) with supplementation of 25OHD₃, alone or in combination with Ca + aP.

6. Supplemental 25OHD₃, alone or in combination with Ca + aP, slightly increased pH₂₄ (P = 0.05) and decreased (P < 0.01) squeezable water loss in breast meat, whereas it had no significant effect on lightness, yellowness and sarcoplasmic protein solubility.

7. In conclusion, the results suggested that enhancing vitamin D status by 25OHD₃ supplementation alone or in combination with Ca + aP may improve sternum structure and mineral accretion. Furthermore, supplemental 25OHD₃, even in a nutritionally complete diet, may offer an effective way to improve protein solubility in female broilers.     

Precipitation Chemistry as an Indicator of Urban Air Quality in Mersin, North-Eastern Mediterranean Region

The chemical composition of precipitation in the city of Mersin on the Mediterranean coast of Turkey has been studied. Spatial and temporal variability of rainwater constituents have been determined from samples collected at two central and two suburban stations for the December 2003–May 2005 period. A total of 246 samples covering all precipitation events were analyzed to determine pH, conductivity, as well as major anion (Cl^?, ${\text{NO}}_3^ - $ , ${\text{SO}}_4^{2 - } $ ); major cation (H⁺, Na⁺, K⁺, Ca²⁺, Mg²⁺, ${\text{NH}}_4^ + $ ) and formaldehyde (HCHO) concentrations. The pH varied within a range of 4.8–8.5, with only 8 out of 246 samples being acidic (pH?<?5.6), and the remaining highly alkaline samples being neutralized by either ${\text{NH}}_4^ + $ in rainwater, or by CaCO₃ resulting from wet deposition of atmospheric dust. The volume weighted mean ΣAnion/ΣCation ratio was 0.49. The equivalent concentration of major ionic species followed the order: ${\text{Ca}}^{2 + } > {\text{HCO}}_3^ - > {\text{SO}}_4^{2 - } > {\text{Cl}}^ - > {\text{NH}}_4^ + > {\text{Na}}^ + > {\text{Mg}}^{2 + } > {\text{NO}}_3^ - > {\text{K}}^ + > {\text{H}}^ + $ . Formaldehyde concentrations varied in the range of 0.01–17.9 μM, and was found to be dependent on precipitation volume. Relatively higher ${\text{NH}}_4^ + $ , ${\text{SO}}_4^{2 - } $ , ${\text{NO}}_3^ - $ and HCHO concentrations, mainly of anthropogenic origin, measured near the city center suggest increased pollution from local anthropogenic sources, e.g., residential heating, industrial and/or traffic emissions. In general, the results of this study suggest local precipitation chemistry is more strongly influenced by natural (mineral dust and marine) sources compared to anthropogenic ones.