Effects of fasting and refeeding on the antioxidant system in cockerels and pullets

The effect of fasting and refeeding on total antioxidant status (TAS), glutathione peroxidase (GSH-Px) activity and concentration of some non-enzymatic antioxidant compounds was studied in cockerels and pullets. Blood was collected before and after 48-h fasting and 24 h after refeeding. In cockerels, fasting resulted in a significant decrease of TAS and uric acid concentration. After refeeding, the concentration of TAS remained significantly lower as compared to the control level. At the same time, blood plasma level of total lipids increased in comparison to the control and post-fasting values. In pullets, fasting resulted in a significant decrease of whole blood haemolysate GSH-Px activity and blood plasma concentrations of albumin and uric acid. Simultaneously, a significant increase in total lipids and cholesterol was obtained. In pullets, refeeding resulted in a further decrease of TAS to undetectable values, a significant decrease of blood plasma cholesterol, and a significant increase of GSH-Px in the whole blood haemolysate and in blood plasma uric acid content. The results indicate that fasting has a negative impact on the antioxidant defence system of the blood, which leads to a reduced resistance to oxidative stress in both cockerels and pullets. However, pullets seem to be more susceptible to fasting-provoked oxidative stress than cockerels.     

DOPPLER ECHOCARDIOGRAPHY IN THE NORMAL DOG: PART I VELOCITY FINDINGS AND FLOW PATTERNS

This study examined the blood flow velocities and flow patterns in the normal dog using pulsed wave spectral Doppler echocardiography in eight areas of the heart. Two breeds of dogs, aged between 8 and 112 weeks and of both sexes, were used. The dogs were fully conscious and no drugs were used. The areas examined were the mitral valve, left atrium, tricuspid valve, right atrium, aorta, left ventricular outflow tract, pulmonary valve and the right ventricular outflow tract. The peak and mean velocities, direction of flow and whether flow was systolic or diastolic was determined for each of these flow areas. Additionally each of these waveforms were described. Aortic flow was also measured from the thoracic inlet by continuous wave Doppler.     

Nuclearia pattersoni sp. n. (Filosea), a new species of amphizoic amoeba isolated from gills of roach (Rutilus rutilus), and its rickettsial endosymbiont

A new species of amphizoic amoeba, Nuclearia pattersoni sp. n., isolated from gills of Rutilus rutilus L. is described. It is characterised by elongate flattened trophozoites of irregular shape. The longer dimension of their bodies is 13.2 (11.0-15.7) microm. Filopodia radiating mostly from the poles are 2 to 2.5 times longer than the body. The diameter of less frequently observed spherical trophozoites is 8.2-10.8 microm; their filopodia radiate to all directions. Cyst-like stages have shorter pseudopodia that arise from one pole only. The surface of locomotive forms from agar plate cultures has a thin amorphous glycocalyx, while most cells are covered by two layers of extracellular matrix. Mitochondria have flattened cristae, dictyosomes are located in the perinuclear zone. A conspicuous ultrastructural feature of the morphologically similar N. simplex, perinuclear striated band, is not present. Light microscopic and ultrastructural data are completed with the sequence of SSU rRNA gene and phylogenetic analysis including sequences of related taxa. The bacterial endosymbiont found in N. pattersoni type strain RR2G2 is assigned to the genus Rickettsia.     

Insect pest management agents: hormonogen esters (juvenogens)

The chemical part of this investigation focused on designing structures and synthesizing a series of six new esters (juvenogens), derived from biologically active insect juvenile hormone bioanalogues (juvenoids, JHAs) and unsaturated short-chain linear and branched fatty acids for possible application as biochemically targeted insect hormonogen agents. The structures of the new compounds were assigned on the basis of a detailed NMR analysis of their (1)H and (13)C NMR spectra. The biological part of this investigation focused on introductory biological screening tests with these compounds against the red firebug (Pyrrhocoris apterus), termites (Reticulitermes santonensis and Prorhinotermes simplex), and the blowfly (Neobellieria bullata). The biological activity of the juvenogens was studied in relation to the fatty acid functionality in the structures. Notable biological activity in topical tests and medium activity in peroral tests was found for the juvenogens 3 and 7 with P. apterus. The compounds 6 and 8 showed the lowest activity in both topical and oral assays with P. apterus. Considerable effect of all tested juvenogens was observed in P. simplex; however, the juvenogens 5 and 6 (derivatives of the only branched short-chain fatty acid) showed no activity against R. santonensis. The effect of the compounds 3-8 on larval hatching of N. bullata was only moderate (larval hatching 80-90%); however, the proliferation effect caused by 5, 6, and 8 is more pronounced than the effect caused by 3, 4, and 7.     

皮暗斑螟性信息素研究

通过室内人工饲养与枣树林间定时定点观测相结合的方法,对皮暗斑螟的生殖生物学进行观测.傍晚(17-20时)羽化的成虫占总量的45.71%,交尾多于午夜后至凌晨前进行.在室内通过气相色谱与触角电位测定相结合的方法,测定皮暗斑螟雄蛾对来自雌蛾性腺的不同化合物的反应,通过应用全二维气相色谱飞行时间质谱分析技术,初步明确了皮暗斑螟性信息素组分为(Z9,E12)-十四碳-9,12-二烯-1-醇[(Z,E)-9,12-14:OH]和(Z9)-十四碳-9-烯-1醇(Z9-14:OH).对二组分及其同分异构体的单体和混合物进行了林间引诱试验,初步结果表明(Z,E)-9,12-14:OH的诱虫效果较好.5,50,500和1 000 μg不同剂量诱芯的田间引诱试验证明,500 μg剂量诱芯诱虫量最多.     

Mayflies (Ephemeroptera) as indicators of environmental changes in the past five decades: a case study from the Morava and Odra River Basins (Czech Republic)

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Haematological and biochemical profile of harvest-size carp during harvest and post-harvest storage

Stress load on harvest‐size common carp (Cyprinus carpio L.) just before harvest, during harvest and during the post‐harvest storage were assessed using haematological and biochemical indices. The study was carried out at the 60 ha Dřemliny pond for 28, 7 and 1 day before harvest, during 3‐day harvest and after a 28‐day post‐harvest period. Indices monitored included the relative spleen weight (SSI), erythrocyte count (Er), haemoglobin levels (Hb), haematocrit (PCV), MCV, MCH, MCHC, leucocrit (Bc), differential leucocyte count (leucogram), blood plasma cortisol, glucose, total proteins (TP), cholesterol and chloride. During harvest, a significant decrease of SSI (P<0.05; P<0.01), increase of PCV (P<0.01), decrease of Bc (P<0.01, P<0.05), lymphopenia (P<0.05) and neutrophilia (P<0.01) were observed. A significant increase in the levels of blood plasma cortisol was found 1 day before harvest (P<0.05) due to draining off the pond before harvest itself, hyperglycaemia was observed 1 day before harvest (P<0.05) and during harvest (P<0.01); a decrease, on the other hand, was found in cholesterol and chloride levels (P<0.01). The relationships between oxygen content in water and SSI and MCHC were positive (P>0.05) and between oxygen and glucose were negative (P>0.01). A 28‐day post‐harvest storage returned the indices investigated back to physiological interval of values. Persistently lower levels of Bc, lymphopenia, neutrophilia and lower TP concentrations are indicative of deepening immunosuppression during the post‐harvest storage period. Changes of haematological and biochemical indices during harvest in relation to hypoxia, fish handling and higher stocking rates are also discussed.     

Mercury concentrations in forest trees from Slovakia

The concentration of mercury has been determined in assimilation organs of forest trees from 10 main industrial regions of Slovakia, four mountain forests and one military area and compared with concentration of mercury from 1356 permanent monitoring plots of Slovakia. The mercury concentration ranges for 2 yr old needles of Picea abies Karst. were (in mg kg^?1): 1.249–4.402 (Rudnany iron ore mines), 0.013–0.749 (nine other industrial regions), 0.021–0.737 (four mountain forests) and 0.053–0.538 (military area). The mercury content in the soil (0–5 cm) from a mercury smelting plant ranged from 9.9 to 130 mg kg^?1, and the moss Pleurozium schreberi contained 3.8–9.1 mg kg^?1. The values obtained were compared with the available literature data.     

Fish-isolated strains of Hartmannella vermiformis page, 1967: morphology, phylogeny and molecular diagnosis of the species in tissue lesions

Based on morphological and molecular characterisation, four amoeba strains isolated from organs of freshwater fish were identified as Hartmannella vermiformis Page, 1967. Small subunit rRNA gene sequences of these strains expand the set of corresponding complete and almost complete sequences of this species to twelve. A new species-specific oligonucleotide probe inferred from recently available SSU rRNA gene sequences was designed and successfully tested in tissue lesions produced by one strain of H. vermiformis in experimentally infected fish.     

Are cadmium, lead and mercury concentrations in mosses across Europe primarily determined by atmospheric deposition of these metals?

Purpose

This study aimed at investigating correlations between heavy metal concentrations in mosses and modelled deposition values as well as other site-specific and regional characteristics to determine which factors primarily affect cadmium, lead and mercury concentrations in mosses. The resulting relationships could potentially be used to enhance the spatial resolution of heavy metal deposition maps across Europe.

Materials and methods

Modelled heavy metal deposition data and data on the concentration of heavy metals in naturally growing mosses were integrated into a geographic information system and analysed by means of bivariate rank correlation analysis and multivariate decision trees. Modelled deposition data were validated annually with deposition measurements at up to 63 EMEP measurement stations within the European Monitoring and Evaluation Programme (EMEP), and mosses were collected at up to 7,000 sites at 5-year intervals between 1990 and 2005.

Results and discussion

Moderate to high correlations were found between cadmium and lead concentrations in mosses and modelled atmospheric deposition of these metals: Spearman rank correlation coefficients were between 0.62 and 0.67, and 0.67 and 0.73 for cadmium and lead, respectively (p?<?0.001). Multivariate decision tree analyses showed that cadmium and lead concentrations in mosses were primarily determined by the atmospheric deposition of these metals, followed by emissions of the metals. Low to very low correlations were observed between mercury concentrations in mosses and modelled atmospheric deposition of mercury. According to the multivariate analyses, spatial variations of the mercury concentration in mosses was primarily associated with the sampled moss species and not with the modelled deposition, but regional differences in the atmospheric chemistry of mercury and corresponding interactions with the moss may also be involved.

Conclusions

At least for cadmium and lead, concentrations in mosses are a valuable tool in determining and mapping the spatial variation in atmospheric deposition across Europe at a high spatial resolution. For mercury, more studies are needed to elucidate interactions of different chemical species with the moss.