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For characterization of the ability of crops to reflect changing soil properties after the addition of ameliorative materials into the soil both pot and rhizobox experiments were provided. In the pot experiment, the influence of the addition of lime and limestone into contaminated Cambisol containing 7.14 mg Cd/kg, 2174 mg Pb/kg, and 270 mg Zn/kg on element availability for spring wheat was tested. The ameliorative materials were added into the pots containing 5 kg of soil in amount of 3 g CaO, and 5.36 g CaCO₃ per kg of the soil. Soil pH reached up to 7.3 in lime treatments compared to 5.7 in control soil. Mobile portion of soil elements (0.01 mol/l CaCl₂ extractable) dropped by 80% for Zn, 50% for Cd, and 20% for Pb, respectively. In both straw and grains of wheat reduced content of elements was observed in limed pots compared to the control ones. For a detailed characterization of the influence of root exudates on the strength of developed complexes in comparison with the bulk soil, short-term rhizobox experiment was set up under identical soil and lime treatments. Generally, the results of rhizobox experiment confirmed the findings from the pot experiment discussed above. Content of elements in shoots and roots of wheat dropped mainly in the case of Cd and Pb. Soil mobile portion of all three tested elements introduced clear depletion curve in control treatment, both limed treatments showed high stability of element complexes almost unaffected by wheat roots.

The physiological response to application of elemental sulphur (S) and cadmium (Cd) of maize (Zea mays L.) grown for 60 days in pot soil was studied. The S was added into the soil with 2 rates (0 and 50 mmol/kg) and Cd was added in solution in 4 rates (0, 20, 50, 100 mg/kg). All the S and Cd were added before planting. Shoot biomass decreased with the application of Cd to the soil whether S was applied or not. The application of S and Cd to soil led to an increasing accumulation of Cd in the shoots of maize. The concentration of chlorophyll was reduced significantly in Cd-treated plants with or without supplementary S. The content of malondialdehyde (MDA) was increased significantly in treatments with S and Cd, compared to the control. The activity of peroxidases (POD) was increased but catalase (CAT) was decreased in plants treated with Cd, again with or without S, in comparison with control. POD and CAT activities decreased in all the Cd treated plants with S, as compared to the plants without S. The results suggest that Cd reduces the crop growth, concentration of chlorophyll and activity of CAT, but increases the content of MDA and activity of POD. S supplies decrease the content of MDA, activities of POD and CAT, as compared to zero S supplies at the same rate of Cd application.

Germination responses to temperature, medium and gibberellic acid (GA3) treatments were studied in kiwifruit (Actinidia deliciosaChev. cv. Hayward) seeds. The seeds treated with four GA3concentrations (0, 2,000, 4,000 and 6,000 ppm) were sown in trays with peat moss, perlite + heater humus and soil mixture and subjected to the temperatures of 20°C, 25°C, 30°C and 35°C with bottom heating, under controlled conditions. All the treatments significantly affected the kiwifruit seeds germination. Seeds sown in peat moss and subjected to the temperature of 35°C with bottom heating reached the maximum germination percentage (99.17%). Peat moss and 6,000 ppm GA3 treatment also had a high germination rate (79%). Moreover, peat moss caused an earlier start of germination than the other mediums and shortened the germination period.

In 2003 to 2005, Chrysomela populi L. gradated on yearly cut Populus nigra var. italica in street alleys in Brno and elsewhere. Imagoes occurred on trees from the end of April or from the beginning of May. In rearing, the chrysomelid consumed unwillingly leaves of 2-year shoots and laid on average 142 eggs. On leaves of shoots, imagoes damaged 100 to 200 cm² during 5 to 7 weeks, produced 480 to 900 frass pellets and laid on average 506 eggs. Oviposition was continual with breaks amounting to on average 2.6 days. Embryonal development took 6 to 8 (in the laboratory 5) days. Larvae of the 1^st generation occurred from mid-May to mid-July. In the course of 2 weeks (in the laboratory during 10 days) of life, they damaged about 20 cm² leaves and produced about 300 frass pallets. In the laboratory, prepupae took 2 days and pupae 4 days. Imagoes of the 1^st generation occurred from June to September. They damaged on average 113 cm² and produced on average 553 frass pellets and 653 eggs. At a temperature of 24 to 28°C, imagoes damaged on average 84 cm² during 2 to 3 weeks and diapaused until the next year. On growing up leaves, imagoes lived longer showing higher consumption of food and higher fecundity as against new fully-grown leaves. Larvae of the 2^nd generation destroyed on average 2 cm² smaller area than larvae of the 1^st generation. Part or all imagoes of the 2^nd generation diapaused. Imagoes of the 3^rd generation damaged 40 to 70 cm² leaves before departure to wintering grounds. In our natural conditions, the prospective 3^rd generation is always incomplete. Cleonice callida Meig. and Schizonotus sieboldi (Ratz.) rank among important enemies.

During 4 years, 27 cultivars and breeding lines of winter wheat (Triticum aestivum) were tested in small plot experiments for resistance to powdery mildew fungus. The most resistant were Frimegu, RE9607, Runal, Asset, Folke and Wasmo. The cultivars Asta (Pm2,6) and Vlasta (Pm2,6 and another not determined specific gene or minor genes of resistance) fall into resistant cultivars. It seems that the specific genes of resistance Pm2 and Pm6 are still very effective against the present Czech population of powdery mildew on wheat. Resistance of the cultivars Hereward and Tarso, having the gene of resistance Pm8, can be ascribed to an additional undetermined gene that is effective only in mature plants. The cultivars Mikon and Ramiro with partial resistance had a higher infection type and disease severity than resistant cultivars, but lower disease severity than the susceptible cultivar Kanzler.

Two spring phenophases (bud-burst and leaf unfolding) of a parent stand and naturally regenerated undergrowth of European beech were observed in conditions under different stand density over the last 10 years. The results proved the unequal onset of phenophases of the parent stand individuals in relation to their sociological status. In the case of codominant and dominant trees the delay of 2-5 days was observed in comparison with subdominant trees. The influence of the parent stand structure on the onset of the undergrowth phenophases was also observed. The onset of phenophases differed by 2-20 days among individuals grown under different density of the parent stand. The onset and course of phenophases also differed between the years. The trend of the average onset of leafing in the period 1995-2004 shows a shift to earlier dates by about three days. Temperature summation of average daily temperatures with the base temperature of 8°C, in the framework of the model predicted bud-burst of beech, showed the lowest variability in comparison with other temperatures.

The aim of the present study was to develop a rapid and inexpensive method for the determination of methylmercury in fish tissues based on GC/ECD instrumentation. The new method is based on acidic digestion in hydrochloric acid and subsequent extraction with toluene. Methylmercury is determined by the GC/ECD technique using a DB-608 capillary column. The following parameters of the method were established: detection limit 13 μg/kg, limit of quantification 22 μg/kg, linearity 0.2-200 ng/ml, reproducibility 9.4%, and recovery 90%. The method was developed and verified using CRM 464 reference material and was successfully tested in inter-laboratory comparisons IMEP - 20 "Trace elements in tuna fish" organised by the Joint Research Centre - Institute for Reference Materials and Measurements (Belgium), with the success rate of E_n=0.43.

The bionomics of Acarus siro was studied at 18 and 20°C and 70 and 80% R.H. on wheat germs, linseed, rapeseed and sunflowers to obtain data for optimisation of biological control of stored product mites on oilseeds. Wheat germs were used as a control substrate as they were considered optimal for development of A. siro. The development of eggs and larvae was longer than that of protonymphs and tritonymphs. Wheat germs appeared to be a better substrate for the development of mites than oilseeds. Generally, the life span of females as well as the oviposition period was shortest on wheat germs while longest on sunflower; also, at the higher temperature the female life span was shorter. The maximum number of eggs laid by a single female (356) was recorded on wheat germs at 20°C and 80% R.H. The development was significantly shorter at 20°C than at 18°C regardless of humidity. There were no significant differences between the effects of the tested oilseeds.

The relationship between type traits in Holstein cows over generations was analysed. The analysed data set included a total of 12 157 dam-daughter pairs with linear scores of 14 type traits including a final score and general characteristics of type. Significant relationships existed between linear type traits in dams and their daughters. Pearson correlation coefficients ranged from r = 0.20 to r = 0.63 except the rump angle. A negative correlation (r = -0.02) was found for this trait. A similar tendency resulted from the analysis of the relationship between values of general characteristics and the final type score.

A pot experiment focused on the study of factors influencing thallium transfer from contaminated soils into kale (green cabbage, Brassica oleracea L. var. acephala, variety Winterbor F1) was evaluated. Three different types of topsoils with naturally low content of thallium (heavy, medium and medium-light soil) were used for pot experiments. The soils were contaminated with thallium sulfate to achieve five levels of contamination (0, 0.52, 2.10, 4.20 and 5.88 mg/kg). There were six replicates for each combination (90 pots in the experiment). The first part of the experiment started in the year of contamination (2001) and continued in 2003. The soil samples and the samples of kale (leaves and stalks were sampled separately) were collected and analysed. Kale was found to be able to accumulate Tl without any influence on yield. The highest thallium concentration was found in the leaves of kale in the first year of the experiment and reached 326 mg/kg dry matter. Bioaccumulation factor (Biological Absorption Coefficient - BAC) was found to be over 80 during the first year of the experiment. In the third year the BAC was around 3 for the soil with the highest pH and the highest organic matter content but as high as 15 for an acid soil with the lowest content of organic matter and the lowest Cation Exchange Capacity (CEC) of soils. The content of thallium in the leaves of kale was found to be 7 to 10 times higher than in the stalks in the third year. In the first year this ratio was up to 18. From these findings it can be concluded that the ability of some plants of Brassicacea family, that are planted as common vegetables, to accumulate thallium is very high and can be a serious danger for food chains. Neutral soils high in CEC and organic matter are able to bind thallium more effectively than poor acid soils and the transfer of Tl into plants from these soils is substantially lower. The uptake of Tl from contaminated soils into kale can be very high and without any negative effect on the plant growth. The transfer of Tl into kale decreases with the time necessary to reach the equilibrium between the added Tl and the soil (ageing of a sample).

Fungi representing Alternaria spp. are ubiquitous pathogens that may under certain conditions cause spoilage of various food crops. Several Alternaria species are known producers of toxic secondary metabolites in some fruits and vegetables, nevertheless, only limited knowledge is available on the occurrence of these mycotoxins in legumes and/or oilseeds used for human nutrition. In the first part of the presented study, the analytical method employing reversed phase high-performance liquid chromatography (HPLC) coupled with fluorescence detection (FLD) was implemented to enable the examination of these food commodities for the presence of altenuene (AE), alternariol (AOH), and alternariol monomethyl ether (AME); the limits of detection were 1, 3 and 2 µg/kg for AE, AOH, and AME, respectively. Altogether 122 flax and 84 pea seed samples grown under organic and/or conventional farming conditions were analysed in the years 2002-2003. AME was detected in 20 flax seed samples; AE and AOH were present in only 2 and 4 samples, respectively. More frequent incidence of Alternaria toxins was recognised in fibre flax seeds as compared to linseed samples. Compared to the crops from the conventional farming, the concentrations of these mycotoxins found in positive organic samples were higher. No Alternaria mycotoxins were detected in the pea samples, probably due to the presence of antifungal compounds in the respective crop.

A modified electrometric method was described in sheep, goats and cattle and used to demonstrate in vitro inhibition of plasma and erythrocyte cholinesterase activities by the organophosphate and carbamate insecticides dichlorvos and carbaryl, respectively. A typical reaction mixture for the measurement of cholinesterase activity contained 3 ml distilled water, 3 ml barbital-phosphate buffer (pH 8.1), 0.2 ml plasma or erythrocytes and 0.1 ml acetylthiocholine iodide (7.5%) as a substrate. The mixture was incubated at 37^οC for 30 min in sheep, 40 min in goats and 20 min in cattle. The pH of the reaction mixture was determined by a pH meter before and after the incubation. The initial pH was measured before the substrate addition. The enzyme activity was expressed as ∆pH/incubation time = (pH1 - pH2) - ∆pH of blank. The method of inhibitor-cholinesterase incubation was used to measure the in vitro inhibition of plasma and erythrocyte cholinesterase activities. Dichlorvos in concentrations of 0.5 and 1 μm inhibited plasma and erythrocyte cholinesterase activities by 24-85%, whereas carbaryl in concentrations of 5 and 10 μm inhibited them by 50-89%. The results suggest that the described electrometric method could be efficiently used for detecting cholinesterase inhibition in ruminants, and further point to the value of the present experimental protocol of in vitro cholinesterase inhibition in preliminary toxicological examinations of anticholinesterase compounds

The purpose of the present study was to investigate the effects of feeding peat as a supplement in the period after weaning on the performance and health status of pigs. Also to assess the risk of the development of tuberculous lesions in the lymph nodes and parenchymatous organs, caused by conditionally pathogenic mycobacteria present in peat. Twenty Large White × Landrace pigs in equal numbers of barrows and gilts (mean live weight 18.0 ± 1.7 kg) were used in the experiment. The experimental group was fed a diet containing commercial underground peat in the dose of 80 g peat/kg dry matter for 30 days. Subsequently, they were fed an identical diet with the control group without peat for 60 days. A short-time feeding peat did not significantly affect the growth and performance of pigs. From day 21, a statistically highly significant (P < 0.01) increase in the consumption of the experimental diet was recorded, however, without a positive effect on the growth of experimental animals. The conversion of the peat containing diet was comparable to the conversion of the control diet. It follows from the results of biochemical analysis of blood that peat feeding for 30 days did not adversely affect the metabolic profile and health status of experimental animals. No tuberculous or tuberculoid lesions in lymph nodes or parenchymatous organs were detected in any of 20 slaughtered animals. Despite that, mycobacteria were isolated from 10 (25.0%) tissues of 5 (50.0%) pigs from the experimental group. One isolate was identified as Mycobacterium avium subsp. hominissuis (IS901- and IS1245+). Seven of nine isolates were determined as conditionally pathogenic atypical mycobacteria: M. fortuitum (n = 2) and M. xenopi (n = 5). It follows from the present results that feeding of a peat supplemented diet to pigs may be considered as economically non-effective and due to the findings of mycobacteria as risky.

In 2002 a study focused on the evaluation of height and density of expanding natural regeneration of Fraxinus excelsior L. (FE) was carried out on Velká hora Hill, a locality in the Bohemian Karst (Český kras). The examined area is located in Karlštejn National Nature Reserve and takes up around 31 ha. The parent rock is limestone. The expansion depends on soil and exposition conditions and relates to the water balance gradient. FE reached the highest densities (up to 6,000 individuals/400 m²) on Velká hora's peak plateau on medium-deep, heavy-textured decarbonized soils. The lowest expansion (508 individuals/400 m²) was found on slopes fully exposed to south (S) with water retention capacity lower than 20 mm. In total, the average density was 1,190 individuals/400 m². FE natural regeneration reached the highest average heights (around 210 cm) on Fageto-Quercetum illimerosum mesotrophicum, the smallest heights on Carpineto-Aceretum saxatile. Average height in the locality was 47 cm. No relation was found between FE natural regeneration height or density and the distance of a fertile specimen. The distance exceeded 70 m only in 3.4%. FE seeds could be detected almost everywhere at the area. FE is capable to establish itself on any location of the studied locality except ecologically extreme parts of rock steppe without forest and Fagus sylvatica L. stands occupying S slopes. On less favourable sites it is capable to use the protection of other tree species and as a low growing tree it can eventually dominate the site. In more favourable conditions it expands on the whole area, where it can dominate the undergrowth already at 1-m height. If the forest sites are left to natural development, a distinctive change in the tree species composition could take place in a short time period. Such a change could have an essential impact on light conditions, energy flux and species composition of plant and animal communities.

The formation of 3-chloropropane-1,2-diol (3-MCPD) released from its esters with higher fatty acids was studied using the recognised precursors of 3-MCPD (tripalmitin, 1,3-dipalmitin, 1-monopalmitin and soybean oil) in the presence of sodium chloride. The precursors were reacted with sodium chloride in an emulsion stabilised with an emulsifier under conditions which modelled the thermal treatment of foods during processing. The highest amount of bound 3-MCPD (released from its esters) was formed from 1-monopalmitin followed by 1,3-dipalmitin, whereas tripalmitin and soybean oil yielded the lowest levels of bound 3-MCPD. Four sets of experiments were then carried out aimed at monitoring the influence of various factors (soybean oil amount, NaCl content, water content, and temperature) on the yield of bound 3-MCPD. The formation of bound 3-MCPD was directly proportional to the concentration of either oil or NaCl. The highest amount of bound 3-MCPD was formed in media containing approximately 20% water. The amount of bound 3-MCPD decreased with increasing temperature over the range 100-230°C and reached its highest value at 100°C. Models with 1,2-dipalmitoyl-3-chloropropane-1,2-diol showed that the decomposition rate of this ester rapidly increased with increasing temperature over the range 100-230°C being the lowest at 100°C and the highest at 230°C.

Disulphide bonds and sulphhydryl concentrations were evaluated to determine the effects on rheological, thermodynamic, pasting, and dynamic rheological characteristics of mixed flours. Gluten samples, first treated with sodium sulphite of different concentrations, were added into flour at a 4% level, which had a significant impact on free sulphhydryl, disulphide bonds, and the ratio of the two indices. There was no relevance between the ratio and other parameters except for free sulphhydryl. The mixed flour doughs had reduced water absorption, dough development time, dough stability time as well as degree of weakening (P < 0.05). Disulphide bonds were associated negatively with the rate of starch gelatinisation (C3-C2), peak, and setback and these characteristics were correlated strongly with dough development time, dough stability time, and progressive protein weakening (C2-C1). The stability of starch gelatinisation and cooking stability of mixed flours did not remain significantly different. The larger the concentration of sodium sulphite, the higher the peak, breakdown, final viscosity, and setback values, but there were no significant differences between samples. For all samples, storage modulus and loss modulus increased with increasing scanning frequency. For mixed doughs, the trend lines of moduli decreased with increasing levels of reduction in added gluten. There was no substantial effect on thermal properties of flours.

Forty male lambs of the mountain Greek breed were used to evaluate the effect of age at slaughter on carcass characteristics and composition. The slaughter of lambs was carried out at the age of 30, 45, 60, 75 and 90 days. The slaughter procedure, carcass dissection and carcass composition were realized according to the standard method of CIHEAM-AGRIMED programme. The results of this work showed that the lambs of different age groups did not differ in dressing percentage significantly. The proportion of muscles showed a tendency of increase with the increasing slaughter age but the differences were not significant. The proportion of total fat in carcass increased with the increasing slaughter age from 20.84 to 23.59% for the age group of 30 and 90 days, respectively (P < 0.05). On the contrary, as the age at slaughter increased, the proportion of bones decreased (P < 0.05). Subcutaneous, intermuscular, perinephric and pelvic fats increased with the slaughter age, but only the subcutaneous fat was influenced significantly (P < 0.05). Among the different commercial cuts proportions of long leg, first 5 ribs and shoulder decreased, while those of last 8 ribs-loin and breast-flank increased (P < 0.05). The overall results suggest that the slaughter age of lambs of the mountain Greek breed should be increased from the present ~45 days to more advanced age of 75 or 90 days in order to improve the farmers' profits without serious negative effects on the quality of carcasses or meat of lambs.

Presented paper is dealing with operation load of three-point hitch (TPH) of agriculture tractor in randomly changeable working conditions and their simulation in laboratory. The basic goal was to obtain experimental data, after which we can judge and analyze problematic of dynamic load of wheel tractor at plowing with orientation on TPH. Another goal was using obtained result from operating measures on their simulation in laboratory conditions by hydrostatic simulator. In presented paper is solved power analysis in each elements TPH of agricultural tractor ZTS 160 45URII A. The tractor during exploiting was in set with four-ploughshare carried and five-ploughshare semi-mounted plough. The measuring was realized for 3 varieties of set speed (gear ratio I/2, I/3, I/1), 3 depths of plowing (20, 25 and 27 cm) and 3 varieties of TPH - positional, mixed and draught control.

In 2003, 2004 and 2005 milk fat composition was determined three times in 55 dairy cows of Czech Pied cattle housed in a byre with stanchions and fed under conditions usual on Czech production farms. Fatty acids were determined by a gas chromatographic method, 26 acids out of the total 37 acids observed in chromatograms were identified. The highest proportions were observed for palmitic acid (29.25 ± 2.98%), oleic acid (24.47 ± 3.27%), myristic acid (12.14 ± 1.80%) and stearic acid (8.91 ± 2.44%). The proportions of saturated, unsaturated and monounsaturated fatty acids were 64.71 ± 4.18, 31.96 ± 4.20 and 27.45 ± 3.42% of total acids, respectively. The total proportion of nutritionally undesirable lauric, myristic and palmitic acid was 45.26 ± 4.77%, while that of the desirable group of polyunsaturated fatty acids was 4.51 ± 1.09%. The observed relatively wide ranges of the individual groups of fatty acids indicate that it is possible to improve the milk fat composition in Czech Pied cows.

In total 20 grown cultivars and advanced selections were included in a two-year study of apple skin thickness. The mean skin thickness of single cultivars measured on classical histological sections through the skin varied from 33.3 μm to 73.1 μm. The late ripening cultivars (Resista,Melrose, Angold and Zuzana) had a thicker skin than the earlier ripening ones. Direct measurements of the apple skin showed that its thickness was not uniform but variable to a great extent between single slices even within a very short distance. The magnitude of variability seemed to be also somewhat dependent on the cultivar. The skin thickness was significantly influenced by the year in some cultivars. The greatest difference in this respect was found in Gala Must where the skin was much thicker in 2003 than 2004. A close relationship was found between the varietal means of skin thickness obtained by direct measurement and corresponding mean scores of panellists. The values of Idared and Topaz were notably remote from the regression line. This disagreement was probably related to different skin structures of both cultivars.

Thirteen germplasm lines of vegetable Chenopodium (C. album) were evaluated in a randomized block design with three replications to estimate the foliage yield and its seven contributing quality traits for three successive cuttings. The variability present in vegetable Chenopodium and interactions operating at various levels were also studied. The mean foliage yield was maximum for CA-II (3.03 ± 0.39 kg/plot), followed by CA-VII (2.94 ± 0.27 kg/plot) and CA-VI (2.41 ± 0.20 kg/plot). Moisture content showed a constant decrease in all germplasm lines with successive cuttings except for CA-IX in 3^rd cutting. Protein content exhibited a strong trend of increase with each successive cutting and was maximum in 3^rd cutting. Protein content showed the highest heritability in 1^st cutting (96.35%) while the values were highest for ascorbic acid in 2^nd and 3^rd cutting. The carotenoid content and ascorbic acid exhibited consistently high genetic gain in all the three cuttings.

The interaction of manganese with cadmium (Cd) toxicity was studied on maize plants grown in hydroponics. Manganese supplied as MnSO₄clearly alleviated the toxic effect of cadmium on the root growth of maize seedlings. The magnitude of alleviation was dose dependant and total abolition of 10µM Cd toxicity on root growth was observed at Mn/Cd ratio of 20:1. The 12 h pre-treatment with 10μM Cd was generally toxic for nitrate uptake and reduction (both determined in Cd-free media). The beneficial effect of 100μM Mn on this toxicity was confirmed for the low-affinity nitrate uptake system, but on the other hand, Mn alone seems to be slightly toxic for high affinity nitrate uptake system and on the nitrate reductase activity.

An expert estimate of the weight of emissions produced in agriculture has been up to now made only through a final counting to the total REZZO 4 emission balance in the category of "other mobile sources" The existing situation is however unbearable since a proper methodology to determine the production of emissions in agriculture, i.e. in the department with a considerable consumption of fossil fuels, is still missing. The solution consists in a more precise specification of the weight of generated limited pollutants (CO, NO_x, SO₂, PM and VOC including CO₂) in the department of agriculture on the basis of the measured annual consumption of fuels in agriculture and with using the emission factors of fuels. Calculated results are compared with the original values finally counted for the REZZO 4 category of "other mobile sources" in 2000 and 2001 (Adamec 2002; Adamec et el. 2003). The calculation revealed that the weight production of individual pollutants in 2000 and 2001 reached only 28% and 27% for CO, 52% and 50% for NO_x, 69% and 66% for SO₂, 87% and 83% for PM, and 26% and 24% for VOC of the original estimates with final counts and was therefore much lower. The share of agriculture in the weight production of emissions from mobile sources in 2000 and 2001 was 3.1% and 3.1% for CO, 11.5% and 11.5% for NO_x, 19.8% and 18.8% for SO₂, 38.3% and 34.6% for PM, and 3.5% and 3.6% for VOC. The development of weight production for individual pollutants in the period from 1995-2005 is expressed by means of regression equations. Coefficients of reliability indicate that the measure of reliability of the interval determined by calculation is much higher than that of the reliability interval determined by values estimated through final counting that appear incidental. There are increasing efforts today focused on the replacement of diesel oil as a traditional fossil fuel in agriculture with biodiesel oil as a more environment-friendly fuel. The second part of results includes a monitoring of the impact of biodiesel oil emissions in cases where diesel oil was replaced by this ecological fuel in agriculture in the period from 2000-2005. It follows from the analysis that the weight production of pollutants in 2000-2005 would have been reduced by 4% in CO, by 28% in SO₂, by 52% in PM and by 4% in VOC while an increase by 20% and 32% would have been recorded in CO₂ and NO_x, respectively. Regression equations are used to express the development of the weight production of individual diesel oil and biodiesel oil pollutants in the period from 2000-2005. Reliability coefficients that are of constant character indicate that the development of the weight of pollutants from diesel oil replicates the development of biodiesel oil pollutants. The significance of achieved results consists in the provision of a more accurate general balance of emissions from one of so called other mobile sources in Czech Republic (apart from the department of transport), thus contributing among other things to a more accurate expression of the total weight of emission production within REZZO 4.

The development of individual cotton bollworm stages depending on the ambient temperature was studied in laboratory conditions. The effect of temperature on the development of all stages of Helicoverpa armigera was studied at three constant temperatures of 20, 25, and 30°C in temperature-controlled chambers. The temperature dependence of the developmental rates and the thermal thresholds were established by means of linear regression. Our data has established following optimal temperatures: the lower thermal threshold for the development of the Helicoverpa armigera eggs is 14.83°C, for the development of the larvae is 11.34°C and for the development of the pupae is 8.18°C. The termal constant for the development of the Helicoverpa armigera eggs is 64.10 day-degrees, for the development of the larvae is 344.83 day-degrees and for the development of the pupae is 222.22 day-degrees. The lower thermal threshold for the total Helicoverpa armigera development is 11.50°C and the thermal constant is 625.00 day-degrees.

An experiment was conducted to investigate the effects of glutamine on growth performance of weanling piglets. Sixty piglets weaned at 21 days of age were randomly assigned to two groups (10 piglets per pen, 3 pens per group). The control group received a maize-soybean meal-based diet. The treatment group received a maize-soybean meal-based diet supplemented with 1.0% free l-glutamine. Piglets were fed the diets for 20 days. Results showed that piglets fed the glutamine diet had lower diarrhoea ratio and shorter diarrhoea duration than those fed the control diet during 20 days after weaning. During the first ten days after weaning, pigs supplemented with glutamine had a 12.05% lower feed:gain ratio than those fed the control diet (P < 0.05). During the second ten days after weaning, they had a 27.75% higher average daily gain than those fed the control diet (P < 0.05); there were no differences in the feed:gain ratio and average daily feed intake. During the first ten days after weaning, the serum urea nitrogen of pigs supplemented with glutamine was reduced by 17.36% (P > 0.05) compared to the control. During the second ten days after weaning, serum urea nitrogen was reduced by 4.27% and serum concentrations of total protein increased by 18.70% in pigs supplemented with glutamine compared to the control (P > 0.05). There were no differences in albumin, T_3, T₄ and growth hormone.

The evaluation of a series (1961-2000) of ombrographic records from 13 selected stations of Czech Hydrometeorological Institute provided long-term annual summation values and annual peaks of the rainfallrunoff erosivity factor R in the USLE. The evaluation indicated that by defining an erosive rainfall event as (a) rainfall ≥ 12.5 mm or (b) rainfall intensity > 6 mm per 15 minutes, there were on average 8 erosive rainfall events per station, varying from 1 to 25. The long-term summation values of R factor were in the range of 42 to 106 (average 66) and annual peaks ranged from 19 to 38 (average 29). If the criteria (a) and (b) were to be fulfilled simultaneously, there were on average more than 2 erosive rainfall events per year per station, the number varying from 0 to 12. The long-term summation values of R factor ranged from 25 to 67 (average 45), with annual peaks from 17 to 36 (average 27.5). The long-term investigations of soil losses by erosion on experimental runoff plots, near Třebsín (Prague-West district), caused by storms, reveal that these losses were mostly caused by rainfall events satisfying both criteria (a) and (b) at the same time. The results of this investigation suggest that the average value of the erosivity factor R = 20 recommended for the Czech Republic until now should be increased to R = 45 and/or 66, which in practical terms would necessitate more stringent conservation measures.

The objective of the present study was to examine if luteal blood flow (LBF) monitoring could be used as an additional prognostic tool for early pregnancy diagnosis, and we particularly focused on the differences in LBF between pregnant and nonpregnant mares. Furthermore, other possible developmental differences of corpus luteum (CL) between pregnant and nonpregnant mares were evaluated. The CL (n = 119) of 27 mares were monitored once daily in B- and Power-Doppler Mode on days 1, 2, 9, 12, and 16 after ovulation (day 0 = ovulation). The data were evaluated using the MIXED Linear Model with repeated measures, and parameters were estimated by the REML method. The course of LBF, area of CL, and pixel intensity differed in nonpregnant mares on a day-to-day basis in contrast to more stable values in pregnant mares. Further, the profiles of the courses were identical until day 9, but since day 12 the differences between pregnant and nonpregnant mares started to be prominent. The LBF, pixel intensity, and level of progesterone (P4) were similar in all mares until day 16, when smaller LBF, lower pixel intensity, and lower levels of P4 were found in nonpregnant mares (P = 0.04, P = 0.02, P < 0.05, respectively). In pregnant and nonpregnant mares the LBF was weakly (r = 0.29 in both) and pixel intensity strongly (r = 0.48 and 0.59, respectively) correlated to the levels of P4. LBF was strongly correlated to the area of CL in pregnant as well as nonpregnant mares (r = 0.72 and 0.64, respectively). In accordance with the results presented in our study we can state that LBF monitoring is not a suitable tool for early pregnancy diagnosis or prognosis as the differences between pregnant and nonpregnant mares are notable - similarly to other indicators of CL status - just after the onset of luteolysis (day 16) when embryo itself is detectable.

For at least 25 years, processes involving structural changes have been growing more and more intense in the countries of Central and Eastern Europe, with these processes including a decline in the number of small farms. The main aim of this paper is to present the mechanisms involved in, as well as barriers to and costs preventing the exit of farms from agriculture, including those that make it difficult to transfer production resources which are being released to other companies. This research takes the form of an overview and is based on the output of new institutional economics, and on transaction cost and rent-seeking theories in particular. The most frequent difficulties encountered in the process of exit from farming include low profitability of production and the shortage of capital among potential buyers, while the lack of sellers' financial resources and the necessity of incurring expenses related to preparing and finalising the sale of resources held by them (the actual transaction costs related to closing down farms) are frequently overlooked. The most important barriers preventing the complete liquidation of farms are the inherent transaction costs categorised as expenses, as well as the emotional costs and costs of alternatives, which are difficult to evaluate and estimate. The following notions are particularly helpful in explaining barriers to exit from farming: the concept of transaction costs and rent-seeking theory, which are both a part of the stream of thought of new institutional economics.

A 14-year-old neutered female Yorkshire terrier presented with a rapidly growing gluteal mass. There was a history of surgical resection of a mass diagnosed as a grade two soft tissue sarcoma in the same region a year earlier. The second mass was surgically excised and histopathologically diagnosed as grade two soft tissue sarcoma. A further relapse occurred six months after the second surgery. On that occasion, the dog was treated with metronomic chemotherapy consisting of cyclophosphamide and piroxicam, which failed to adequately control the disease and the mass increased 2.5-fold in size in three weeks. Imatinib treatment was started, after which there was a 62% reduction in the size of the mass. The patient has remained in partial remission for five months. To the authors' knowledge, this is the first report on the use of imatinib to treat canine soft tissue sarcoma. Imatinib might be a useful treatment for soft tissue sarcoma that recurs after surgical resection.