The effect of dietary methionine levels on fattening performance and selected blood and tissue parameters of turkeys

A total of 490 eight-week-old female Hybrid Converter turkeys (body weight 4.11 ± 0.03 kg) were divided into 5 groups with 7 replicates of 14 birds each. For 8 weeks, basal diets were supplemented with methionine (Met) at following levels (weeks 9–12/weeks 13–16 of age): Group 1 – 0.34/0.29%, Group 2 – 0.39/0.34%, Groups 3 and 4 – 0.45/0.38% and 0.51/0.41%, respectively, Group 5 – 0.58/0.47%. Only in the first feeding phase the body weight gain (BWG) was affected by Met levels with the significantly highest BWG in Group 3. No treatment effects were found for feed conversion ratio, carcass yield, carcass composition and meat colour. The blood superoxide dismutase activity was significantly highest in Groups 2 and 3. The concentrations of reduced glutathione in the liver were linearly increased (p = 0.018), whereas the ratio of reduced glutathione to oxidised glutathione was highest in Group 3 (quadratic contrast, p = 0.004). It can be concluded that turkeys from Group 3 (Met levels age depending 15% and 10% above recommendations by NRC) were characterised by a well-balanced physiological response. Attention should be paid to the immune response of birds to higher dietary Met levels: plasma IgA concentrations decreased, whereas IL-6 and TNF-α levels increased in turkeys fed diets with the highest Met content.     

The influence of carbon dioxide-induced water acidification on the osmotic and metabolic responses of the Baltic amphipod Gammarus oceanicus

The aim of this study was to investigate the effect of CO₂-induced water acidification (pH values: 8.1 ? control, 7.5 and 7.0) on the hemolymph osmolality and total metabolic rate of amphipod Gammarus oceanicus under short-term exposure. The hemolymph osmolality was measured using a vapor pressure osmometer. The metabolic rate was determined based on the heat dissipation measurements using a Calvet-type isothermal twin calorimeter. The hemolymph osmolality remained unchanged after exposure to pH 7.5 and it increased in the lowest treatment. Acidification did not significantly affect the resting or active metabolic rate. The observed results indicate that high osmolality maintained during hypercapnia did not generate additional physiological costs. It may therefore be concluded that the studied species is preadapted for this factor. The long-term adaptation to hypoosmotic conditions in the brackish Baltic Sea might also have preadapted it to hypercapnia because similar physiological mechanisms are responsible for the resistance to both factors.     

The effect of polyphenols and vitamin E on the antioxidant status and meat quality of broiler chickens exposed to high temperature

The aim of this study was to determine the effect of a polyphenol product (PP) (Proviox) and vitamin E on the antioxidant status and meat quality of broiler chickens exposed to high temperature. The experimental materials comprised 120 ROSS 308 broilers (6 treatments, 10 replications, 2 birds per replication). Dietary supplementation with vitamin E and PP was applied in the following experimental design: group I (negative control) – without supplementation; group II (positive control) – without supplementation; group III – supplementation with 100 mg vitamin E/kg; group IV – 200 mg vitamin E/kg; group V – 100 mg vitamin E/kg and 100 mg PP/kg; group VI – 200 mg PP/kg. In groups II–VI, broiler chickens aged 21–35 d were exposed to increased temperature (34°C for 10 h daily). In chickens exposed to high temperature, dietary supplementation with antioxidants, mostly PP, improved growth performance parameters, including body weight, body weight gain and feed intake until 28 d of age. Vitamin E added to broiler chicken diets at 200 mg/kg and vitamin E combined with PP was most effective in improving the total antioxidant status of birds, enhancing blood antioxidant enzyme activities and increasing vitamin E concentrations in the liver and breast muscles. Broilers fed diets supplemented with 200 mg/kg of vitamin E alone and vitamin E in combination with PP were characterised by a higher percentage content of breast muscles in the carcass. Dietary supplementation with antioxidants improved the water-holding capacity of meat, reduced natural drip loss and increased the crude ash content of meat. The breast muscles of chickens fed diets supplemented with PP had a lower contribution of yellowness. The breast muscles of chickens receiving diets with 100 mg vitamin E/kg(group III) and diets supplemented with PP (groups V and VI) were characterised by the highest concentrations of polyunsaturated fatty acids. The PP can be a valuable component of diets for broiler chickens exposed to high temperature.     

Design,synthesis and evaluation of activity and pharmacokinetic profile of new derivatives of xanthone and piperazine in the central nervous system

Searching for CNS active cyclic amines derivatives containing heterocyclic xanthone core we designed and synthesized a set of fourteen novel 2- or 4-methylxanthone substituted by alkyl- or aryl-piperazine moieties. The compounds were evaluated in vivo for their potential antidepressant-like activity (in the forced swim test) and anxiolytic-like activity (four-plate test) and their inhibitory effect against rat 5-HT₂ receptor was checked. The pharmacokinetic analysis of active compounds done by a non-compartmental approach have shown a rapid absorption of all studied molecules from intraperitoneal cavity and good penetration the blood-brain barrier after i.p. administration with brain to plasma ratios varied from 2.8 to 31.6. Genotoxicity and biotransformation of active compounds were studied. Compound 19 interactions with major classes of GPCRs, uptake systems and ion channels were tested and results indicated that it binds to 5-HT_2A, 5-HT_2B receptors and sodium channels.     

Development of LCA benchmarks for Austrian torrent control structures

The International Journal of Life Cycle Assessment - This study emerged from a research project that aimed to develop a Life Cycle Assessment (LCA) model for torrent control structures. This...     

Antimicrobial and antioxidative potential of free and immobilised cellobiose dehydrogenase isolated from wood degrading fungi

Cellobiose dehydrogenase (CDH, EC 1.1.99.18) is a glycoprotein having many biotechnological applications. In the present study, CDHs isolated from Phlebia lindtneri (PlCDH), Phanerochaete chrysosporium (PchCDH), Cerrena unicolor (CuCDH), and Pycnoporus sanguineus (PsCDH) were studied the first time for their ability to generate antioxidant and antimicrobial agents. The aim of the research was to evaluate the antioxidant and antimicrobial activity of systems composed of four CDHs and lactose or cellobiose as a reaction substrate. The free radical scavenging effect of free and immobilised enzymes was evaluated using the DPPH method. The lowest values of EC₅₀ (10.04 ± 0.75 $\text{μg}$/ml) was noted for PlCDH/lactose and for PlCDH/cellobiose (12.06 ± 1.35 $\text{μg}$/ml). The EC₅₀value reached 12.6 ± 1.51 $\text{μg}$/ml in the case of PsCDH/lactose and 15.96 ± 1.35 for PsCDH. The CDH preparations were also effectively immobilised in alginate (the immobilisation efficiency expressed as a protein yield ranged from 61.6 to 100 %). The operational stability expressed as a scavenging effect showed the possibility of using the alginate beads 4 times. Both the free and immobilised CDHs as well as the CDH/substrate were tested against Gram-negative Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, and Gram-positive Staphylococcus aureus ATCC 25923 bacteria. All samples, except PlCDH, were potentially effective in suppression of bacterial growth. The highest percentage of inhibition (100 %) was obtained for S. aureus bacteria using PsCDH and PchCDH with lactose as a substrate, whereas a slightly lesser effect was observed for E. coli and P. aeruginosa bacterial cells, i.e. 64.1 % and 86.5 % (PsCDH) and 94.1 % and 41.4 % (PchCDH), respectively. Furthermore, the concentrations of the reaction products (aldonic acids and hydrogen peroxide) were quantified and the surface morphology of the alginate beads was analysed using SEM visualisation.     

Does inbreeding affect personality traits?

The question of why variation is maintained in personality traits is an evolutionary puzzle. According to the condition‐dependence hypothesis, such traits depend on condition, which limits the behavioral choices available to individuals. Because condition is affected by many genes, it can effectively be manipulated by inbreeding, which exposes the effects of deleterious recessive mutations. Here, I compared two personality traits, boldness and tendency to explore, of male guppies (Poecilia reticulata) from first‐generation inbred and outbred treatments. Boldness in guppies is associated with increased sexual attractiveness and is thus expected to affect fitness. Therefore, I hypothesized that the personality traits would be negatively affected by inbreeding. However, the results indicated that inbred guppies did not differ in either personality trait from their outbred counterparts. This finding suggests that mechanisms other than condition dependence are maintaining personality variation in the guppy.     

A polyhydroxyalkanoates bioprocess improvement case study based on four fed-batch feeding strategies

The modelling and optimization of a process for the production of the medium chain length polyhydroxyalkanoate (mcl-PHA) by the bacterium Pseudomonas putida KT2440 when fed a synthetic fatty acid mixture (SFAM) was investigated. Four novel feeding strategies were developed and tested using a constructed model and the optimum one implemented in further experiments. This strategy yielded a cell dry weight of 70.6 g l⁻¹ in 25 h containing 38% PHA using SFAM at 5 l scale. A phosphate starvation strategy was implemented to improve PHA content, and this yielded 94.1 g l⁻¹ in 25 h containing 56% PHA using SFAM at 5 l scale. The process was successfully operated at 20 l resulting in a cell dry weight of 91.2 g l⁻¹ containing 65% PHA at the end of a 25-h incubation.