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Monitoring of physical activity for management of cow reproductionT. Berka, M. Štípková, J. Volek, D. Řehák, G. Matějů, F. JílekCzech J. Anim. Sci., 2004, 49(7):281-288 | DOI: 10.17221/4311-CJAS The objective of this paper was to assess by means of pedometers the period of anoestrus in a herd where the calving interval was 400 days and to detect the influence of some factors (breed, year, season, parity) on the length of anoestrus and the intensity of increased physical activity during oestrus. It was also monitored whether the intensity of increased physical activity would influence the conception rate. The observations were performed in a herd of 243 cows, 80 of them Czech Pied cows (C) and 163 of themHolstein cows (H) during 4 years. The cows were housed together in a free cubicle housing system. The cows of H breed produced 3 790 kg and those of C breed 3 087 kg of milk on average during the first 100 days of lactation. The mean calving interval was 400 days, and the mean number of services per pregnancy was 2.1. The cows were fed a total mixed ration. This ration has a low energy content (NEL) and excessive content of crude protein according to the official evaluation used in theCzechRepublic. The intake of NEL ensured the production of 30.9 l of milk and the intake of crude protein in 45 l of milk in these cows. The cows of both breeds significantly differed in the length of postpartal anoestrus, which is probably related to the negative energetic balance of H cows. The effect of parity, year of calving, and season of calving on the length of postpartum anoestrus was not demonstrated as statistically significant. A comparison of the walking activity over the oestrus period in the individual breeds demonstrated that the cows of the Czech Pied breed exhibited significantly higher activity. The highest walking activity was observed in first-calvers of both breeds, and the lowest walking activity during oestrus was recorded in winter. The cows with higher walking activity had a higher conception rate than those with lower walking activity. |
Littoral 0+ fish assemblages in three reservoirs of the Nové Mlýny dam (Czech Republic)P. Jurajda, J. RegendaCzech J. Anim. Sci., 2004, 49(10):450-457 | DOI: 10.17221/4331-CJAS A synchronous study of 0+ juvenile fish in three lowland reservoirs (Mušov, Věstonice, Nové Mlýny) of the Nové Mlýny dam (Czech Republic) was conducted in July 1997. Fish were sampled by fry beach seine and backpack electro fishing gear at 32 sites in three types of inshore habitats: concrete stepped embankment, stony rip-rap and sandy-gravel beach. In total, we registered 0+ juvenile fish of 17 species and one hybrid. The most common species was bleak Alburnus alburnus (62.7%), followed by roach Rutilus rutilus (12.8%), ide Leuciscus idus (6.2%) and asp Aspius aspius (5.5%). More than 53% of 0+ fish samples were caught in beach sites, 43% in rip-rap sites and only 3.4% in concrete embankment. The littoral assemblages of 0+ fish differed between the three adjacent reservoirs and also between the shoreline types. |
Assessment of metal contamination in the upper reaches of the Tichá Orlice RiverZ. Svobodová, O. Čelechovská, J. Kolářová, T. Randák, V. ŽlábekCzech J. Anim. Sci., 2004, 49(10):458-464 | DOI: 10.17221/4332-CJAS The aim of the present study was to assess metal contamination in the same reaches of the river, and thus to help explain unsatisfactory reproduction results in the reproduction of salmonoid fish. The contamination assessment was based on measuring metal concentrations in the brown trout (Salmo trutta morpha fario) and some bottom sediment samples. The samples were collected in June 2000 and 2001 at two collection sites from theTicháOrliceRiver (Červená Voda - 103rd river km; Lichkov - 93rd river km) and its tributary Kralický Brook (100th river km). At each of the sites, 14 brown trouts were collected in each of the periods of monitoring. The AAS method was used to determine the total mercury, arsenic, cadmium, lead, copper, zinc, chromium and nickel contents in the muscle tissue of the fish and in aquatic sediments. The Kralický Brook is an important anthropogenic source of metal contamination (particularly of mercury and copper) for theTicháOrliceRiver. The highest concentrations of mercury in muscles of brown trout were found at the Kralický Brook (0.37 ± 0.08 and 0.40 ± 0.08 mg/kg) and Lichkov (0.41 ± 0.10 and 0.34 ± 0.07 mg/kg) in 2000 and 2001 and the lowest concentration at Červená Voda (0.017 ± 0.02 mg/kg in the same years). Significantly higher concentrations of arsenic (in 2000: 0.30 ± 0.08 mg/kg; in 2001: 0.38 ± 0.07 mg/kg) were found in the muscle tissue of the brown trout collected at Červená Voda than at the downstream site Lichkov (in 2000: 0.18 ± 0.09 mg/kg;in 2001: 0.14 ± 0.07 mg/kg). The authors hypothesize that the difference was due to different conditions (principally water temperature). It seems reasonable to assume that unsatisfactory results in the reproduction of fish from the upper reaches of theTicháOrliceRiver are due not only to organic pollutants but also to mercury compounds that are classified among suspect endocrine disruptors. |
Flaminia, a self-incompatible peach variety: Short communicationC.G. Tsipouridis, T. ThomidisHort. Sci. (Prague), 2003, 30(3):121-122 | DOI: 10.17221/3872-HORTSCI This study showed that the peach variety Flaminia is self-incompatible in Northern Greece, and it produces fruits only after cross fertilization. Among the peach varieties Doukessa, Fayette, Late Naoussas, Princess Anne and Autumn Free used as pollinators, the peach variety Fayette was found as the best in Northern Greece. |
Dendrochronology of Scots pine (Pinus sylvestris L.) in the mountains of PolandS. Wilczyński, J. SkrzyszewskiJ. For. Sci., 2003, 49(3):95-103 | DOI: 10.17221/4684-JFS In the area of southern Poland 33 pine stands growing at the altitudes from 350 to 1,200 m above sea level in the Carpathian and Sudeten Mountains were selected as the object of studies. Thirty-three site chronologies of tree-rings, representing each site were constructed. A decrease in the similarity of dendrochronological signal chronologies occurred with the growing distance between the sites. Correlation and convergence analysis and the Principal Components Analysis permitted the differentiation of two chronology groups: the Western (Sudeten) and the Eastern (Carpathian) ones. On the basis of the site chronologies regional chronologies for the Carpathian and Sudeten Mts. were constructed. The investigated pines from the two regions manifested great sensitivity to winter frost and in summer to the deficiency of heat and water. The chronologies were strongly integrated by the pattern of air temperatures, being differentiated by the pluvial conditions. |
Biological and chemical amelioration effects on the localities degraded by bulldozer site preparation in the Ore Mts. - Czech RepublicV.V. Podrázský, J. Remeš, I. UlbrichováJ. For. Sci., 2003, 49(4):141-147 | DOI: 10.17221/4689-JFS Biological and chemical (fertilising, liming) amelioration are among the principal tools used to restore degraded sites. These techniques were also used on the Ore Mts. plateau on plots prepared by bulldozing. We evaluated the impact of these amelioration techniques by measuring tree species primary production and humus form restoration. Begun in 1983-1985, this project studied growth reaction of forest stands by measuring height and diameter increment, for the following species (blue spruce Picea pungens Engelm., European larch Larix decidua Mill., lodgepole pine Pinus contorta Dougl., Eastern white pine Pinus strobus L., alder Alnus incana Moench., European beech Fagus sylvatica L.) during the period 1994-2000. The growth potential by species decreases in the following order: larch, alder, lodgepole pine, white pine, blue spruce. Beech was almost exterminated by red deer browsing and the harsh climate; pines suffered heavily from browsing and bark stripping. Holorganic horizons were measured and basic soil chemical and mechanical characteristics were determined - pH, soil adsorption complex characteristics (using Kappen's methodology), content of the humus and total nitrogen, exchangeable acidity and plant available macronutrients, granulometric composition of mineral soil horizons. Our results confirmed the relatively long-lasting effects of soil amendments, as well as the amelioration effects of alder, and the relatively inhibiting effects of larch and blue spruce. |
Biological activity, nitrogen dynamics, and chemical characteristics of forest soils in the Šumava national parkM. SvobodaJ. For. Sci., 2003, 49(7):302-312 | DOI: 10.17221/4704-JFS This paper deals with large-scale mountain forest decline in the Šumava National Park. The changes in biotic and abiotic properties of forest sites follow the tree layer disintegration. Changed microclimatic conditions such as intensity of irradiance, moisture and temperature of the top holorganic layers together with altered development of ground vegetation could strongly affect the values of microbiological respiration activity and the rates of nitrogen mineralization and nitrification. Soil substrates, built of organic mater, located on stony locations, are endangered by introskeletal erosion. This paper compares these features in pairs of research plots, consisting of dead or cut forest and of living stand. According to the results of this study, higher rates of organic matter decomposition, transformed dynamics of nitrogen and other nutrients and possible nutrient leaching from soil solutions were demonstrated in the forest floor under declined spruce stands. The extent and seriousness of these adverse processes for forest soils are strongly site dependent. |
Effects of overstory structure and fire regime upon diversity and abundance of selected understory species in longleaf pine (Pinus palustris Mill.) forests in southeastern GeorgiaW. Keith Moser, Chui Kwan YuJ. For. Sci., 2003, 49(9):395-402 | DOI: 10.17221/4787-JFS We examined the impacts of variation in overstory structure and burning regime on understory vegetation in the longleaf pine (Pinus palustris Mill.) forest of the Okefenokee National Wildlife Refuge in southeastern Georgia, U.S.A. On sandy upland sites surrounding the Okefenokee Swamp and on islands, we established five randomly-located 0.04-ha plots within each of six study areas. The plots varied in overstory density, past management and fire regime. We measured overstory tree size of longleaf pines in the 0.04-ha plots and percent cover of ground cover species in five 1-m2 subplots nested within each 0.04-ha plot. We also calculated diversity indices for the ground cover species. There was no significant relationship between overstory basal area and any diversity measure. Even at the subplot level, there was no significant relationship observed between the diversity measures and distance to the nearest tree, presumably a surrogate for overstory density. The diameter (DBH) of the nearest tree exhibited a slight influence over the Shannon Index, and the nearest tree's height was significantly related to evenness in each subplot. There were varied relationships between individual species and fire regime or nearest tree measurements. There was a definite, but statistically insignificant, trend of decreasing diversity with increasing years since the last burn. Height of the nearest tree positively influenced evenness, probably reflecting the influence of stochasticity and amount of needle deposition (influencing fire behavior) over a wide area. Within the generally equal fire-return interval across sites, individual fire-events and site-specific behavior apparently influence understory diversity. It is not surprising that the last burn would affect species richness, even more so than the number of growing-season burns, other studies support this observation. The presence of obligate seeding and (clonal) sprouting as dominants in the ground cover suggests that the fire-return interval is not regular. The cycling of fire-return intervals, even within the management-prescribed 2- to 4-year range, and the variation by microsite appear to provide sufficient variability of disturbance to create diversity in the ground-level cohort. Site-specific relationships between particular species and the nearest tree suggest that even a narrowly-prescribed fire management regime can provide sufficient diversity. |
Early stadiums of floodplain forest succession in a wide river beds upon an example of BečvaJ. KlečkaJ. For. Sci., 2004, 50(7):338-352 | DOI: 10.17221/4631-JFS In the years 1999-2001 early stadiums of succession development of a floodplain forest were monitored in the wide bed of the Bečva River formed during the floods in 1997. Changing site conditions were investigated and the vegetation of pebble beds was repeatedly mapped in detail. In dependence on the site conditions main types of biotopes were described. The vegetation data were evaluated in accordance with the life form and ecological claims of the identified species. The results indicated an increasing differentiation of the originally relatively homogeneous environment owing to fluvial processes and progress of vegetation. Generally hemicryptophytes and hemiheliophytes were thriving above all, the dominance of Phalaris arundinacea was still growing. As for the woody species, especially willows asserted themselves from the beginning, solitarily and weaker in vitality representatives of other genera were present at drier sites. The identified specimen of Myricaria germanica was probably planted artificially. As concerns neophytes, only Reynoutria japonica was spreading significantly but in a very uneven way. Generally, this development of similar communities only little documented in this region corresponds to STG Saliceta fragilis inf. |
Mechanisms of resistance to virusesOriginal PaperJ.P.T. ValkonenPlant Protect. Sci., 2002, 38(10):S132-S135 | DOI: 10.17221/10337-PPS Resistance associated with a hypersensitive response (HR) and subsequent development of necrotic lesions (cell death) at the sites of virus infection can restrict virus movement in plants. Genes for HR are dominant and act on a gene-for-gene basis. Many viral proteins triggering HR have been identified. Also, several genes for HR-based virus resistance, or virus-induced cell death without resistance, have been isolated and characterized in plants, which provides novel insights to the mechanisms of virus resistance. Another international, major research frontier has formed more recently around RNA silencing, a universal RNA surveillance system and inducible virus defence mechanism in multicellular organisms. Many viral proteins interfere with different phases of RNA silencing. The data provide novel insights to break-down of resistance in mixed virus infections (viral synergism), resistance to virus movement, and recovery of plants from virus infection. |
Potentials of organic amendments in the control of plant parasitic nematodesOgechi N. AgbeninPlant Protect. Sci., 2004, 40(1):21-25 | DOI: 10.17221/1351-PPS An increasing number of researchers worldwide are showing interest in organic amendment of soil as means of nematode control. Numerous plant species with nematicidal compounds have been identified. Neem (Azadirachta indica) is considered the best-known example of plants with nematicidal properties and is available commercially in some parts of the world. Its efficiency has been proven locally, with the seed powder giving good control in both field and screenhouse. Several materials are in use as organic amendment. However, the choice of materials for amendment will determine its efficiency in control. The use of organic amendments that are disease-free and with a narrow C:N ratio will improve soil fertility while more efficiently reducing the level of nematodes and minimising the risk of increasing the level of another soil borne pathogens and pest |
Effect of atrazine on glutathione levels, glutathione s-transferase and glutathione reductase activities in pea and wheat plantsLyuba P.-E. Miteva, Sergei V. Ivanov, Vera S. Alexieva, Emanuil N. KaranovPlant Protect. Sci., 2004, 40(1):160-20 | DOI: 10.17221/1352-PPS Changes were studied in the endogenous level of glutathione (total and oxidised), and in the amount of free thiol groups as caused by the herbicide atrazine on two species of plants with different sensitivity to it. The activities of two enzymes related to glutathione metabolism (glutathione reductase and glutathione S-transferase) were also determined. The application of the herbicide on leaf increased the levels of total and oxidised glutathione in pea and wheat plants. Increased activity glutathione S-transferase in wheat plants was found. |
Scab disease of firethorn at selected localities in SlovakiaGabriela Juhásová, Helena Ivanová, Katarína Adamčíková, Marek Kobza, Andrea ČerevkováPlant Protect. Sci., 2004, 40(2):42-48 | DOI: 10.17221/461-PPS The health state of firethorn, Pyracantha coccinea, was evaluated in different types of functional urban greenery at locations in Slovakia during 2001 (34 sites) and 2002 (18 sites). The occurrence of scab disease, caused by the fungus Spilocaea pyracanthae, was recorded. The degree of damage to firethorn fruits was evaluated; it ranged from 3.6% to 98.8% (2001) and from 9.1% to 38.5% (2002). Germination of conidia of the fungus ranged between 42 and 50% at 24-25°C after 24 h, and from 49% to 61% after 48 h. The germination of conidia collected on different parts of the plants from July to September was compared. Conidia taken from olive-green spots on fruits in September had the highest germination (53-89%). |
Origin, mechanism and molecular basis of weed resistance to herbicidesDaniela Chodová, Jan Mikulka, Marie Kočová, Jaroslav SalavaPlant Protect. Sci., 2004, 40(4):151-168 | DOI: 10.17221/463-PPS This review summarises information from the literature and experimental experience of the authors in research on weed resistance to herbicides. Factors conditioning the origin of resistance are described. The origin of resistant weeds to nine active ingredients with a different mode of action is presented chronologically, and the distribution of resistant weeds around the world outlined. The fundamental modes of action: reduction of the target site sensitivity, so-called "target site resistance", and the mode by which a herbicide is metabolised into inactive products, are listed. Function and genetic modifications of target sites of selected herbicides are described. Czech biotypes of resistant weeds with a mutation at codon 264 of the psbA gene encoding the D1 protein and at codon 574 of the acetolactate synthase gene are presented. |
Sulfur and sulfate concentrations in leaves of oilseed rape under field conditionsJ. Matula, M. PechováPlant Soil Environ., 2002, 48(10):433-440 | DOI: 10.17221/4392-PSE In 1999-2001 sulfur and sulfate concentrations were studied in expanded young leaves of rapes of the line variety Lirajet and hybrid variety Pronto at the onset of stem elongation (DC 30), flowering (DC 64) and early maturity (DC 70) in different localities of the Czech Republic. Except the S-deficient site the concentration of total sulfur and sulfates in leaves considerably increased in higher growth stages. A less steep increase in S concentration in leaves was associated with rather humid growing season, especially with April precipitation. Great time variations in sulfur concentrations in leaves signal a possibility of diagnostic misinterpretation of plant analysis without exact definition of growth stage. The shape of trend of variations in S concentration in leaves indicates the S nutritive state of the site and the intensity of upward transport of sulfates with soil moisture in the crop nutrition with sulfur. Good yields of rapeseed were connected with minimum concentration of total sulfur 0.5%, and sulfate sulfur 0.2% in leaf dry matter at DC 30. The proportion of sulfates in total concentration of sulfur in rape leaves ranged from 30 to 60% at the onset of stem extension and it increased in higher phenophases. At flowering, sulfates accounted for 80% and more at sites where sulfate uptake from the soil environment was not problematic. Besides the S-soil test, the results of investigations indicate the importance of CEC value of soil for the preventive diagnosis of S-nutrient state of the site. |
Effects of pre- and post-emergence weed control on weed population and maize yield in different tillage systemsM. Knežević, M. Đurkić, I. Knežević, Z. LončarićPlant Soil Environ., 2003, 49(5):223-229 | DOI: 10.17221/4117-PSE The effect of chemical weed control with reduced herbicide rates (pre-em., pre-em. + post-em., post-em.) on weed population density and maize yield was compared in three tillage systems (mouldboard, chisel, disk harrowing) for lessive pseudogleyic soil in north-eastern Croatia(1997-1999). These main weeds were present in all tillage variants: Echinochloa crus-galli (L.) PB., Chenopodium album L., Ambrosia artemisiifolia L., Polygonum lapathifolium L., Equisetum arvense L. and Calystegia sepium (L.) R.Br. The density of all weeds was significantly affected by tillage and it ranged from 204 plants on untreated plots with mouldboard to 372 and 421 plants per m2 with chisel ploughing and disk harrowing, respectively. In comparison with standard tank-mixture of atrazine herbicide (metolachlor 50% & atrazine 20%) at the recommended rate, atrazine-free herbicide combinations (metolachlor + 50% prosulfuron & 30% primisulfuron-methyl; sulcotrione + bromoxynil; thifensulfuron-methyl + nicosulfuron) showed a similar total efficacy of weed control (95-96%). Band spraying with standard treatment at a half-recommended rate combined with mechanical weed control brought a satisfactory total weed reduction (83-87%). The weed control methods had no effects on maize yields that were significantly affected by year and tillage. Compared to the highest yield with mouldboard ploughing (10.2 t/ha), average percent yield depressions with chisel ploughing and disk harrowing were 10 and 22%, respectively. |
Utilization of the biological nitrogen fixation for soil evaluationT. ŠimonPlant Soil Environ., 2003, 49(8):359-363 | DOI: 10.17221/4137-PSE Non-symbiotic nitrogen fixation (potential nitrogenase activity - PNA) of soil samples originating from different plots of long-term field experiments (selected variants: Nil, NPK [mineral fertilisation: 64.6-100 kg N/ha/year], FYM [farmyard manure], and FYM + NPK from three blocks III, IV and B with different crop rotation) was determined in laboratory experiments. The symbiotic nitrogen fixation (total nitrogenase activity - TNA) of the same soil samples was evaluated in hydroponic experiments with pea (2001, 2002) and lucerne (2001) in which the soil samples were used as a natural inoculum. The high values of PNA were found in the variants fertilised with FYM in all three blocks and all experiments. Simultaneously, the variants fertilised with mineral NPK reached low values of PNA. The farmyard manuring enhanced the number of free-living bacteria Azotobacter spp. that were identified in all soil samples. In the hydroponic experiments with pea, the highest nonsignificant values of TNA were found in variants B 284 (FYM + NPK) and III 254 (FYM + NPK) in 2001, and B 214 (FYM) and III 214 (FYM) in 2002. Plants inoculated with soil from these variants formed also high amounts of nodules (significant differences in block IV in 2001) and plant biomass. In the experiments with lucerne, the nonsignificantly highest TNA values were found in variant III 154 (NPK). Variants from block III (214, 254) and IV (114 and 154) showed the nonsignificantly lowest TNA values. The rhizobia that effectuate symbiosis with pea were more active in the soil samples in 2001 than those forming nodules on lucerne. |
Microbial characteristics, carbon and nitrogen content in cambisols and luvisolsL. Růžek, K. Voříšek, S. Strnadová, M. Nováková, W. BarabaszPlant Soil Environ., 2004, 50(5):196-204 | DOI: 10.17221/4022-PSE Tested soils (1991-2002) were defined by chemical, textural and microbial characteristics. From the tests which describe cambisols, the following parameters have to be stressed. The higher level of Corg (1.20-1.76%), which resulted in quite high microbial biomass carbon content (396-625 µg/g dry soil), high control respiration (0.45-0.80 mg CO2/h/100 g dry soil) and potential nitrification with (NH4)2SO4 (6.7-18.4 mg N-NO3/8 days/100 g dry soil). Studied luvisols reached typical levels: Corg (0.97-1.22%), CMB (398-503 µg/g dry soil), control respiration (0.46-0.57 mg CO2/h/100 g dry soil), potential nitrification with (NH4)2SO4 (3.2-9.9 mg N-NO3/8 days/100 g dry soil). Lower levels of organic carbon and a medium level of microbial biomass raised in higher ratio CMB/Corg (average 4.0%). Highly significant differences (p < 0.01) between cambisols and luvisols were determined for Corg, Nt, pH(KCl), CMB, CMB/Corg, CE, control respiration and potential nitrification, while the difference in potential ammonification with peptone was at level p < 0.05. With the exemption of ratio CMB/Corg all cambisol characteristics were higher than luvisol ones. Studied soils were evaluated by six biological criteria (CMB; ratios: CMB/Corg, CE/CMB, potential/control respiration, potential/control ammonification, potential/control nitrification). These criteria distinguished tested soils into three groups. The first one includes two localities in the mountain region (Červená Voda 809, 810; altitude 565-590 m) defined as stagnic cambisols with higher content of Corg (1.40, respective 1.76%) and simultaneously with the highest biomass of micro-organisms from all tested soils (CMB,625, respective 621 µg/g dry soil). It is not surprising that microbial activities (respiration, nitrification) at these localities were also high. The majority of the studied localities (one eutric cambisol and four luvisols) belongs to the medium group. The third group includes two localities (Neumětely - haplic luvisol, Čistá u Rakovníka - eutric cambisol) where biological criteria was mostly the worst. In the period 1993-2002 microbial biomass carbon was for both sites in the range of 357-458 µg/g dry soil which are not so bad values, but in comparison with localities in mountain wet region they are low. This status was issued in the lower ratio CMB/Corg (2.71-3.77%). |
Spinach and pepper response to nitrogen and sulphur fertilizationM. Smatanová, R. Richter, J. HlušekPlant Soil Environ., 2004, 50(7):303-308 | DOI: 10.17221/4036-PSE A vegetation pot experiment was established to explore the effect of two doses of nitrogen (0.6 and 0.9 gN in the form of ammonium sulphate) and two doses of sulphur (20.6 and 30.6 mg/kg of soil) on the yields and quality of spinach and pepper in comparison with a natural level (7.85 mg/kg). The results of the experiments confirmed that the application of sulphur by means of (NH4)2SO4 in combination with nitrogen had a positive effect on yields and also on the quality of the vegetables. In the sulphur-free variants of spinach the effect was statistically significant and also when the levels of S in the soil were higher. Lower doses of nitrogen under increased levels of sulphur increased the yields statistically significantly (on average by 47%) and the sulphur concentration in the plants increased. The N:S ratio became narrower in proportion with the level of sulphur, particularly under a lower N level. The nitrate content in spinach corresponded with the applied dose of nitrogen and the nitrogen concentration. The sulphur level did not influence the content of C vitamin, but had a positive effect on the content of the essential amino acids cysteine and methionine. A mean level of S1 in combination with a N1 dose significantly increased pepper yields, narrowed the N:S ratio and was reflected in dry matter production per 1 g of N. The highest pepper yields were achieved with a dose of S1, which resulted in the highest dry matter production in the fruit per1 g of N under both levels of N. At the same time increasing the sulphur level reduced the content of nitrate and increased the level of cysteine from 0.11 to 0.305 g/kg. |
Heavy metal distribution between fractions of humic substances in heavily polluted soilsL. Borůvka, O. DrábekPlant Soil Environ., 2004, 50(8):339-345 | DOI: 10.17221/4041-PSE Soil organic matter is important in controlling heavy metal behaviour in soils. This study aims to determine the distribution of organically bound Cd, Pb, and Zn between humic and fulvic acids in 20 samples of heavily polluted Fluvisols. Traditional procedure of alkaline sodium hydroxide/pyrophosphate extraction of humic substances with consequent humic acids precipitation by acidification was used. All of the three metals were bound predominantly on fulvic acids (mean share was 98.4, 82.0, and 95.7% of total organically bound Cd, Pb, and Zn content, respectively). Mainly the level of pollution controlled the amount of metals bound on fulvic acids. On humic acids, a limited amount of specific sorption sites for the metals is expected. Lead content bound on humic acids was negatively correlated with soil pH. The results suggest relatively high potential mobility of organic fractions of heavy metals in soils under this study. The selectivity of alkaline extracting agent is briefly discussed. |
Yield and forage quality of red clover (Trifolium pratense L.) cultivars in the lowland and the mountain regionsJ. Leto, M. Knežević, K. Bošnjak, D. Maćešić, Z. Štafa, V. KozumplikPlant Soil Environ., 2004, 50(9):391-396 | DOI: 10.17221/4049-PSE Six Trifolium pratense L. cultivars, five diploid and one tetraploid, were grown in the lowland region (123 m altitude) and the mountain region (650 m altitude). Dry matter (d.m.) and green mass (g.m.) yield, stem height and leaf proportion were assessed from each of the three growing seasons. Chemical composition was assessed from the average samples of all cuts in the second year of the experiment. Greater green mass (54.14 t/ha) and dry matter yield (9.86 t/ha), stem height (0.61 m), crude protein (157.6 g/kg), crude fiber (222.9 g/kg), crude ash (100.68 g/kg) and crude fat (30.09 g/kg) content were observed in the mountain region, compared to the lowland region (45.61 t/ha g.m. 8.92 t/ha d.m. 0.59 stem height, 156.38 g/kg crude protein, 216.6 g/kg crude fiber, 94.85 g/kg crude ash, 24.98 g/kg crude fat). The greater leaf proportion (47.2%) and nitrogen free extract content (420.13 g/kg) were observed in the lowland region compared to the mountain region (42.95% and 402.99 g/kg, respectively). A significant location × cultivar interaction was found for all investigated parameters except for leaf proportion. |
Engine combustion chamber tightness diagnosticsJ. Pošta, B. Kadleček, T. HladíkRes. Agr. Eng., 2003, 49(3):115-118 | DOI: 10.17221/4961-RAE The modern combustion engines and their systems are getting more complicated and sophisticated nowadays. It is no more possible to verify their function or actual technical state directly. Thus various methods of indirect diagnostics are being developed more and more rapidly. The on-board diagnostics is being increasingly applied to monitor and measure suitable diagnostic signals during operation, deviations from required or expected values are then recorded. This trend requires the application of completely disassembly-free techniques of measurements and the real-time analyzing of measured figures. This paper presents the results of the research on relation between the starter's starting current and the engine combustion chamber tightness. The experiments were carried out for common four-cylinder engine. |
Application of smart sensors in the measurement of soil physical parametersW. Skierucha, A. M Wilczek, R. T WalczakRes. Agr. Eng., 2004, 50(3):96-102 | DOI: 10.17221/4933-RAE The study presents the project and partial implementation of a modern monitoring system for the measurement of soil physical parameters. It is provided with smart sensors equipped with signal conversion electronics, individual identification and communication means decreasing the complexity of the measurement system and also the measurement errors that can appear during analog signal transmission along the cables from the sensors to the measuring unit. The applied wireless communication system operates in the 433MHz ISM (Industrial, Scientific, Medical) licence free frequency band for transmission of commands and data between a remote PC compatible computer (Master unit) and the smart sensors (Slave units) in the distance of several hundred meters. The presented partial implementation of the system measures the temperature at several locations in the soil profile in field conditions and communicates with the host PC computer in wireless way. The developed hardware and software is intended to be adapted to more complex monitoring systems working in compliance with IEEE 1451 smart transducer interface standard and covering large areas as an element of air-borne or satellite remote sensing and serve for ground reference measurements. It is shown that the currently available technical means enable to apply smart sensors and wireless communication in the environmental monitoring in the economically justified way. The small increase of the system price by providing the measuring smart sensors, already equipped some element of control or computation, with radio communication assures the decrease of measurement errors and makes the collection of environmental data convenient for the system operator. |
Counter immunoelectrophoresis: a simple method for the detection of species-specific muscle proteins in heat-processed productsL. Necidová, E. Renová, I. SvobodaVet Med - Czech, 2002, 47(5):143-147 | DOI: 10.17221/5818-VETMED Counter immunoelectrophoresis (CIE) was used for the detection of species-specific muscle proteins in food products. This technique allowed the detection of pork, beef, poultry, or and kangaroo meats in heat-processed products at concentrations below 1.5%. CIE is based on the use of species-specific polyclonal antibodies prepared by immunisation of rabbits with heat-stable antigens extracted from visibly fat-free muscular tissue heated to 75°C, 100°C, or 120°C for 30 minutes. Adulterations in terms of declared product compositions were demonstrated by this method in 7 of the 50 tested commercial products. |
A review of the diseases and contaminant related mortalities of tench (Tinca tinca L.)Z. Svobodova, J. KolarovaVet Med - Czech, 2004, 49(1):19-34 | DOI: 10.17221/5671-VETMED The paper provides a review of the current state of knowledge of parasites, diseases and poisonings of tench (Tinca tinca L.) based on the literature and on the authors own findings. Information on the viruses, bacteria, fungi and parasites reported from tench are provided along with deaths resulting from alterations in environmental quality. Finally, a list of the current known species of parasites and diseases reported in the Czech Republic are provided based on our own investigations carried out at the Research Institute of Fish Culture and Hydrobiology at Vodňany (University of South Bohemia Ceske Budejovice, Czech Republic) between 1984 and 2002. |
A review of rabies elimination in EuropeJ. VitasekVet Med - Czech, 2004, 49(5):171-185 | DOI: 10.17221/5692-VETMED The rabies situation has changed drastically in all European countries where oral vaccination campaigns of red foxes against rabies have been implemented. All types of oral vaccines used have shown to be highly efficacious, enabling rabies elimination over large areas. Several countries are already declared rabies-free according to the internationally conditions set and other countries are in the final stage of this process. In this review, the rabies situation in a number of selected European countries is described, with special emphasis on oral vaccination. |
Digestibility of total and phytate phosphorus in young calvesV. Skrivanova, M. Marounek, R. DvorakVet Med - Czech, 2004, 49(6):191-196 | DOI: 10.17221/5694-VETMED Two experiments were conducted to determine digestibility of total and phytate phosphorus (P) in young calves. In the 1st experiment 14 male calves received a commercial milk replacer (6 l of milk per day) and had free access to a starter concentrate. In the 2nd experiment 21 male calves were divided into 3 groups and fed ad libitum a milk replacer (Group I), milk replacer and starter concentrate (Group II), and milk replacer and silaged maize cobs (Group III). Digestibility measurements were carried out at the age of 10 weeks (1st experiment), and 12 and 16 weeks (2nd experiment). In the 1st experiment phytate P accounted for 27.0% of the total P intake. Phytate P was assayed by capillary isotachophoresis. On average, 27.9% of ingested P, but only 3.0% of phytate P were recovered from the faeces. The proportion of phytate P in total faecal P was 5.8%. In the 2nd experiment phytate P accounted for 8.9, 13.8 and 8.6% of total P in diets of calves of Group I, II and III, respectively. On average, 6.6% of ingested P and 3.6% of phytate P were recovered from the faeces. Dry matter of faeces contained total P, phytate P and phosphate P at 9.74, 0.65 and 4.69 mg/g, respectively. Faecal concentrations of total P significantly correlated with those of calcium (r = 0.71). It can be concluded that young calves utilised phytate P very efficiently as no more than a few % of phytate escaped degradation in the digestive tract. |
Nematodes from the genus Ascaridia parasitizing psittaciform birds: a review and determination keyV. Kajerova, V. Barus, I. LiterakVet Med - Czech, 2004, 49(6):217-223 | DOI: 10.17221/5698-VETMED In parrots (Psittaciformes), seven nematode species of genus Ascaridia have been found so far, both in wild birds and in birds in captivity. Five species are specific for parrots: Ascaridia hermaphrodita, A. sergiomeirai, A. ornata, A. nicobarensis and A. platyceri. Two species: A. galli and A. columbae, that infect gallinaceous and columbiform birds, respectively, were found also in parrots. On the basis of data from the literature and our own observations the taxonomy, synonyms and list of definite hosts of these nematode species were reviewed. The morphometrical features of nematode species were compiled and a determination key was added. |
Passive immunoprophylaxis of edema disease in weaned pigletsP. Alexa, J. Hamrik, K. Stouracova, L. Konstantinova, E. SalajkaVet Med - Czech, 2004, 49(12):447-452 | DOI: 10.17221/5738-VETMED Hyperimmune sera against Shiga toxin Stx2e with antibody titres 8 000-32 000, prepared by immunization of slaughter pigs, were administered subcutaneously to piglets (n = 73) 3 days after weaning. The titres of Stx2e neutralizing antibodies in sera of piglets ranged from 16 to 512 following application of the immune serum. In most of the piglets, passively acquired antibodies disappeared during 4 to 8 weeks after application. The recorded serum titres were in all of the piglets 8 or higher fourteen days following administration. In another experiment, an immune porcine serum with antibody titre against Stx2e of 130 000 was applied subcutaneously into a knee fold to 30 piglets. The serum was applied at the dose 3 ml, 1.5 ml, 0.75 ml, 0.4 ml, 0.2 ml, 0.1 ml, and 0.05 ml based on the group of piglets. Antibody-free serum was applied to pigs of the control group (n = 5). The following day, supernatant of STEC culture with Stx2e titre of 150 000 was applied to piglets of both experimental and control groups into the opposite knee fold that the above serum. Piglets that received 0.2 to 3 ml of serum remained unaffected throughout the experiment following application of supernatant containing Stx2e. Piglets that received 0.05 ml of serum and those of the control group showed severe clinical manifestations of edema disease following Stx2e application and were sacrificed ante finem. Marked signs of the disease could already be observed 18 hrs following Stx2e application. In a group of 3 piglets that received 0.1 ml of serum, mild paralysis was observed in 1 piglet 18 hrs following Stx2e application. |
Approach to comparing complex software implementation methodsI. Vrana, J. VránaAgric. Econ. - Czech, 2005, 51(2):84-92 | DOI: 10.17221/5081-AGRICECON Some of agriculture-food sector information systems are characterised by a high complexity and a large size. There are often many alternative solutions or technologies (implementation methods) and more then one possible way or approach to an information system design. Individual alternatives could considerably differ by their properties, e.g. costs of design of initial functionality, development and operational costs, run-time costs and technical parameters of the resulting information system (e.g. the access time). Unfortunately, existing metrics for quantification of this task usually do not deliver precise results but a rough estimate depending on many variable conditions. The paper will outline typical implementation methods and show approaches to assessment and comparison of certain types of properties of information systems for a computer support for management of large data systems, which use relational database. Authors presented part of these results also at the Agrarian Perspectives conference 2004 in the Applied Informatics session (Vrana I., Vrána J. 2004). |
