Fulltext search in archive
Results 3721 to 3750 of 4875:
Intensively fertilised seedlings of the beech (Fagus sylvaticaL.) for artificial regeneration of the spruce stands in the process of conversionA. Jurásek, J. Bartoš, J. NárovcováJ. For. Sci., 2008, 54(10):452-458 | DOI: 10.17221/41/2008-JFS Artificial regeneration of autochthonous target tree species plays an important role in the process of conversion of forest stands. The European beech is one of the most suitable and most frequently used tree species in this process. Modern technologies of intensive methods of the cultivation of the European beech seedlings provide, among others, a possibility to increase the proportion of this tree species in reforestation more quickly. It is however necessary to test at what types of sites this planting material can be used. The health status and growth of intensively grown beech seedlings in the first years after planting were studied on 2 research plots. Proper intensive fertilisation of the beech seedlings affected positively both the initial height and growth. Even the slow-release fertiliser did not negatively influence the beech after planting. The health status of the beech is excellent after 4 years, the average height of plants with different fertilisation treatments having become equal. It is to conclude from the hitherto obtained results that a slow-release fertiliser in the substrate has a positive effect on the plant growth, and that different fertilisation variants did not cause any serious root deformations of the beech planting stock samples taken 4 years after planting. The impacts of prior nursery fertilisation upon the beech planted under the conditions of extreme sites are further investigated. |
Polyamines during somatic embryo development in Norway spruce (Picea abies [L.])J. Malá, M. Cvikrová, P. Máchová, O. MartincováJ. For. Sci., 2009, 55(2):75-80 | DOI: 10.17221/84/2008-JFS Contents of free polyamines (putrescine, spermidine and spermine) were determined in different developmental stages of Norway spruce (Picea abies [L.] Karst.) somatic embryos by means of HPLC. Determinations were performed embryogenic tissue after 4 weeks of the growth on proliferation medium, after 2 and 5 weeks of the culturing on maturation medium, and 2 weeks after desiccation. Maturation of somatic embryos (after 5 weeks) was accompanied by increase of concentrations of putrescine (2.3 times) and spermidine (3.2 times). In comparison with above mentioned polyamines, spermine concentrations were significantly lower (4.3 times). Two weeks after desiccation, the concentrations of putrescine decreased 5.4 times and spermidine 2.2 times in comparison with mature embryos. To improve the efficiency of somatic embryogenesis of less responsive genotypes, the supplementation of growth media by polyamines is discussed. |
Humus conditions and stand characteristics of artificially established young stands in the process of the transformation of spruce monoculturesL. Menšík, T. Fabiánek, V. Tesař, J. KulhavýJ. For. Sci., 2009, 55(5):215-223 | DOI: 10.17221/18/2009-JFS The main reason for the transformation of spruce monocultures at sites of mixed broadleaved forests is to create more natural relationships between the species structure of a stand and soil processes. The presented study compares humus conditions and basic growth characteristics of two mixed stands (spruce with beech and larch with beech) aged 25 years with a beech stand (aged 40 years) and spruce stand (aged 30 years). The purpose of the study is to evaluate (i) forms of forest floor, (ii) soil reaction, (iii) the content and total reserves of carbon, nitrogen and C/N ratio, (iv) dissolved organic carbon (DOC) in relation to stand characteristics. The highest reserve of forest floor is detected in the mixed stand of larch with beech (52.6 t/ha), the lowest reserve in a beech stand (21.0 t/ha). The soil reaction of the spruce stand and the beech stand is 4.0 (± 0.3) and 5.1 (± 0.3), respectively. The C/N ratio of the spruce stand is 23.5 (± 1.8) and that of the beech stand 18.8 ± 2.9. The DOC content decreases with layers of surface humus towards depth. Mixed stands represent by their values of soil conditions a mean between spruce and beech stands. |
Humus conditions of stands with different proportion of Douglas fir in the Hůrky Training Forest District and Křtiny Training Forest EnterpriseL. Menšík, J. Kulhavý, P. Kantor, M. RemešJ. For. Sci., 2009, 55(8):345-356 | DOI: 10.17221/9/2009-JFS The paper presented evaluates reserves and chemical composition of forest floor of three stands of Douglas fir, spruce and spruce with beech at acid sites (3K) in the Hůrky Training Forest District (TFD) and at a meso-trophic site (4H) in the Křtiny Training Forest Enterprise (TFE). The aim of the study was to evaluate: (i) reserves of forest floor, (ii) soil reaction, (iii) total content of carbon and nitrogen for the forest floor layers, iv) C/N ratio, and (v) the content of dissolved organic carbon (DOC). The lowest reserve occurs in the Douglas fir stand at a mesotrophic site (25.0 t/ha), the highest accumulation occurs in the spruce stand and in the spruce/beech stand at an acid site (79.4-79.6 t/ha). The soil reaction is strongly acid to acid. The most favourable values of pH for forest floor and soil at acid (4.6 ± 0.4) and mesotrophic sites (5.2 ± 0.4) occur in the Douglas fir stand. It also corresponds to C/N ratio (23-26). The highest reserve of carbon in forest floor occurs at the acid site 34.7 t/ha (1.3 t/ha nitrogen). The lowest reserve of carbon in forest floor at the mesotrophic site amounts to 8.5 t/ha (0.4 t/ha nitrogen). The higher content of DOC in stands at acid sites can result in a higher risk of soil acidification. Keywords: spe |
Current possibilities of using Norway spruce (Picea abies [L.] Karst.) in forest regeneration in the air-polluted region of the northeastern Krušné hory Mts.P. Kubík, O. MauerJ. For. Sci., 2009, 55(8):376-386 | DOI: 10.17221/75/2008-JFS The paper analyses possibilities of repeated use of Norway spruce (Picea abies [L.] Karst.) in the regeneration of existing Norway spruce stands, in the regeneration of large-area clearcuts, and in the reconstruction of the stands of substitute tree species (European white birch [Betula verrucosa Ehrh.]) after a change in the emission situation in the northeastern Krušné hory Mts., comparing the prosperity of these plantations with plantations in the unpolluted Bohemian-Moravian Upland. The survey included 26 research plots aged 1-12 years, situated predominantly on acidic sites in Forest Altitudinal Vegetation Zones (FAVZ) 6 and 7 in the northeastern Krušné hory Mts. (air pollution damage zones A and B) and 6 control plots aged 4-11 years on acidic sites of FAVZ 6 in the Bohemian-Moravian Upland (air pollution damage zone C). Total number of parameters and traits assessed in each tree was up to 14. Research results indicate that the current pollution and climatic situation in the Krušné hory Mts. allow a switch to the classical spruce management system of higher elevations. The best method of regeneration is seen in small-size regeneration elements - clearcuts of up to 1 ha. The spruce can also be used on large-area clearcuts, but it suffers from a long transplanting shock and frost injuries there. All plantations must be protected against game damage. |
Plant community variability within potential natural vegetation units: a case study from the Bohemian KarstP. Šamonil, K. Polesná, P. UnarJ. For. Sci., 2009, 55(11):485-501 | DOI: 10.17221/111/2008-JFS : Based on a map of potential natural vegetation (PNV), actual vegetation was studied in the Mramor locality (106.4 ha). A total of 188 relevés were examined using stratified random sampling. A comparison was made between trends in vegetation variability throughout the entire locality and variability within the defined PNV units. The stratification of the locality according to PNV units was only partly representative of the main trends in vegetation variability, especially at ecologically distinctive sites. On the other hand, in areas with a relatively limited ecological gradient, the sites were "oversampled". The variability of plant communities within PNV units was high. The results of this case study suggest that the need for delineation of PNV units which are homogeneous in terms of production, site and phytocoenosis is overestimated. This delineation neither corresponds to the characteristics of actual ecosystems nor is necessary for the application of a PNV system. A more suitable unit for the development of such a system would be, for example, forest type series. |
Electron microscopy of structures present in embryonic cells of plants infected with Plum pox virusJaroslav Polák, Milan Jokeš, Miloslava Ducháčová, Alena Hauptmanová, Petr KomínekPlant Protect. Sci., 2008, 44(3):81-84 | DOI: 10.17221/28/2008-PPS Electron microscopy was used to detect the presence of virus particles or inclusions in growth tips and parenchymatic cells of leaves of plum, apricot and peach trees artificially infected with Plum pox virus (PPV). Typical pinwheels were found in ultrathin sections of leaves of PPV infected plums, apricots and peaches. Filamentous particles or their aggregates approximately 750 nm long were found in ultrathin sections of growth tips of plum, apricot, and peach shoots with a diameter of 0.5 mm. Pinwheels were never present in embryonic cells. No virus particles were found in ultrathin sections of growth tips of PPV infected plum, apricot and peach shoots of 0.2 mm in diameter. Embryonic cells of growth tips up to 0.2 mm in diameter are PPV free. PPV particles are present in growth tips at a distance 0.2-0.5 mm from the top; the virus is probably multiplied in this part of the growth tips. |
Records of Brown spot needle blight related to Lecanosticta acicola in the Czech RepublicLibor JANKOVSKÝ, Dagmar PALOVČÍKOVÁ, Miloň DVOŘÁK, Michal TOMŠOVSKÝPlant Protect. Sci., 2009, 45(1):16-18 | DOI: 10.17221/39/2008-PPS There are two records of brown spot needle blight caused by L. acicola in the Czech Republic up to date. Disease was first reported on June 2007 in National Nature Reserve (NNR) Červená Blata, South Bohemia. A more recent discovery of L. acicola took place on August 2008 in the NNR Borkovická Blata. The disease was observed on 10-60 year old Pinus rotundata. Both locations with infected trees are situated inside nature conservation sites under strict protection regimes that are located approximately 50 km apart. In both sites, L. acicola occurred simultaneously with Dothistroma septospora, the red band needle blight causal agent on Scots pine (Pinus sylvestris), bog pine (P. rotundata) and their hybrid (P. × digenea). However, infections of both diseases on the same tree have not yet been observed. |
Climate change and its possible influence on the occurrence and importance of insect pestsZdeněk LaštůvkaPlant Protect. Sci., 2009, 45(10):S53-S62 | DOI: 10.17221/2829-PPS Insect pests, as widely tolerant and adaptable organisms, may be less distinctly affected by climate change than other insect species. The changing climate may affect the occurrence and impact of the native pests both negatively and positively (increased importance of thermophilous and xerophilous species and decreased importance of psychrophilous ones, noxious abundances of several species also in higher altitudes, decrease of many pests by frost-free winters, low humidity, weather extremes, increased numbers of antagonists, and phenological discrepancy with the host plant). Expansions of new pests into the territory of the Czech Republic, caused by climate change, will be very limited. A small number of greenhouse pests may be expected to occur in outdoor conditions. Increased temperatures may cause a slight increase of non-indigenous invasive insect species and migratory pests. In Central Europe the climate change will intensify the effects of other factors. In the next 20-50 years, the changes in species composition and importance of insect pests of plants will be caused by factors in the following order: (l) introductions of non-indigenous species, (2) new approaches in pest control, (3-4) changes in crop cultivation and representation of crops, (3-4) climate change, (5) other causes (unexpected shifts of ranges, changes in food preferences of insect species, etc.). |
Changes in weed species spectrum of perennial weeds on arable land, meadows and pasturesJan Mikulka, Marta Korčáková, Věra Burešová, Jiří AndrPlant Protect. Sci., 2009, 45(10):S63-S66 | DOI: 10.17221/2805-PPS Occurrence of selected perennial weeds has been monitored at control sites across the Czech Republic since 1989, and trends of their occurrence have been evaluated. The monitoring has been aimed mainly at Cirsium arvense (L.) SCOP, Sonchus arvensis L., Artemisia vulgaris L., Stachys palustris L., Bolboschoenus planiculmis, Bolboschoenus laticarpus, and Elytrigia repens (L.) NEV. on arable land and Taraxacum officinale L.A. on pastures and meadows. High increase in the frequency of occurrence of C. arvense and E. repens was found out in the mid-nineties while the infestation frequency with these two weeds decreased later on. The occurrence of infestation with the other perennial weeds Cirsium arvense, Elytrigia repens, Sonchus arvensis, Bolboschoenus planiculmis, Bolboschoenus laticarpus, Stachys palustris, Artemisia vulgaris and Taraxacum officinale L.A. slightly but continually increased. |
A comparative account of the microbial biomass-N and N-mineralization of soils under natural forest, grassland and crop field from dry tropical region, IndiaJay S. Singh, D.P. Singh, A.K. KashyapPlant Soil Environ., 2009, 55(6):223-230 | DOI: 10.17221/1021-PSE This study investigated microbial biomass-N (MB-N) and N-mineralization in soils of four different vegetation systems including forest (sal), mixed forest, savanna and cropland ecosystems in the Vindhyan region, India. A change was noted in the above region due to physiographic differences and anthropogenic disturbances. Annually the soil moisture (SM) content across the different study sites ranged from 7.5 to 24.3% being maximum in forest sites compared to savanna and cropland sites. The NH4+-N, NO -3 -N and MB-N concentrations varied from 4.3 to 10.2 μg/g, 1.1 to 5.8 μg/g and 21.3 to 90.2 μg/g dry soil, respectively, with minimum values in the wet and maximum values in the dry season. The trend of seasonal variation in net N-mineralization was similar to that of moisture content but counter to the concentrations of inorganic-N and MB-N. The net N-mineralization rates at different investigated sites ranged from 4.5 to 37.6 μg/g month. Cultivation reduced the N-mineralization and MB-N by 58.5% and 63.5%, respectively. Experiments showed that the percentage contribution of MB-N to total-N was 8.01 to 19.15%. MB-N was positively correlated with the inorganic-N (n = 180,r.80,P < 0.001) but negatively with soil moisture (n = 180, r = 0.79, P < 0.001) and net N-mineralization rates (n = 180, r = 0.92, P < 0.0001). The higher N-mineralization and MB-N in the soil of forest ecosystem was reported compared to savanna and cropland and the order of soil MB-N levels and net N-mineralization followed the sequence: forest (sal) > mixed forest > savanna > cropland. |
Nitrogen compounds and enzyme activities in sorghum induced to water deficit during three stagesC.F. Oliveira Neto, A.K.S. Lobato, R.C.L. Costa, W.J.M.S. Maia, B.G. Santos Filho, G.A.R. Alves, B. Brinez, H.K.B. Neves, M.J. Santos Lopes, F.J.R. CruzPlant Soil Environ., 2009, 55(6):238-244 | DOI: 10.17221/84/2009-PSE The aim of this study was to evaluate and explicate the changes in the nitrogen compounds and enzyme activities in Sorghum bicolor plants (cv. BR-700) submitted to water deficit during vegetative, reproductive and maturation stages. The experimental design used was entirely randomized in factorial scheme, with two conditions (control and stress) combined with three stages (vegetative, reproductive and maturation). The nitrate level was increased at 180.6, 72.9 and 78.9% during the vegetative, reproductive and maturation stages, respectively. The total soluble amino acids and glycinebetaine increased only during vegetative and reproductive stages, if compared with control plants. However, besides protein levels during all stages, significant reductions were reported in nitrate reductase and glutamine synthetase activities; free ammonium presented decreases at 37.3 and 77.6% in vegetative and reproductive stages, respectively, when compared with control plants. |
Differences in soil sulfur fractions due to limitation of atmospheric depositionJ. Balík, M. Kulhánek, J. Černý, J. Száková, D. Pavlíková, P. ČermákPlant Soil Environ., 2009, 55(8):344-352 | DOI: 10.17221/101/2009-PSE The aim of this work was to estimate the changes in contents of different sulfur (S) fractions in soils under conditions of lowering inputs of S from emissions together with the influence of application of manure and mineral fertilizers. Soil samples from long-term field experiments were used for this purpose. The samples were taken from 10 sites from precise long-term field experiments with different soil-climatic conditions in the Czech Republic. The samples were analyzed using the following fractionation: (i) water soluble S (H2O extracts), (ii) sorbed S (0.032M NaH2PO4 extracts) and (iii) S occluded with carbonates (1M HCl extract). Furthermore, the concentration of total S (Stot) and organic S (Sorg) was determined. Soil samples were taken in the years 1981 and 2007. During 26 years a decrease of Stot by about 3-8%, water soluble S by 65-68% and sorbed S by 39-44% were observed in the topsoil of the evaluated soils. Furthermore, a low increase in the content of organic S was observed. The estimated ratio of Sorg reached 78.7-80.9% from Stot in the year 1981 and 87.7-89.8% in 2007. Farmyard manure (40 t/ha) applied every 4 years did not have a significant influence on S fractions and Stot contents in soils; intensive S fertilizing increased Stot and mobile S forms contents in soils. Very close correlations were obtained especially between Stot and water soluble S and organic S. |
Detection of Listeria monocytogenes through real-time PCR and biosensor methodsP. Poltronieri, M.D. de Blasi, O.F. D'UrsoPlant Soil Environ., 2009, 55(9):363-369 | DOI: 10.17221/139/2009-PSE Listeria monocytogenes is a foodborne pathogen causing listeriosis, especially in sensitive individuals such as children, pregnant women and persons with compromised immune systems. This pathogen has been isolated from different food products, but milk products surely play a major role in the epidemiology of this foodborne disease. Identification traditionally involved culture methods based on selective enrichment and plating followed by the characterization of Listeria spp. based on colony morphology, sugar fermentation and haemolytic properties. These methods are the gold standard, but in the last years more rapid tests were developed based on antibodies (ELISA) or molecular techniques (PCR or DNA hybridization). More recently, molecular methods were developed that target RNA rather than DNA, such as RT-PCR, real time PCR or nucleic acid sequence-based amplification (NASBA). In this review, real-time PCR assays, protein chip methods and label-free SPR immunosensors were compared for their application in bacterial detection. |
Acid catalysed transesterification of animal waste fatA. Prošková, Z. Kopicová, J. Kučera, L. ŠkarkováRes. Agr. Eng., 2009, 55(1):24-28 | DOI: 10.17221/20/2008-RAE Rendering plant fat (RPF) was collected and different conditions were used for transesterification. The course of transesterification of RPF was compared with that of transesterification of lard under the same conditions. Significant diffe-rences were found between transesterification of RPF and that of lard. Optimum methanol excess for lard transesterification was found to be 30-fold, for RPF 10-fold, optimum sulfuric acid concentration was 1% for lard, 2.5% for RPF. Optimum temperature as well as optimum reaction time were similar in both cases. The fatty acid composition is similar but not identical in both fats. RPF contains a higher amount of free acid which could be the reason for the differences observed. |
Effects of moisture content, internode position and loading rate on the bending characteristics of barley strawOriginal PaperH. Tavakoli, S.S. Mohtasebi, A. JafariRes. Agr. Eng., 2009, 55(2):45-51 | DOI: 10.17221/26/2008-RAE This study was conducted with the aim to evaluate the effects of the moisture content, internode position, and loading rate on the bending characteristics of barley straw including bending stress and Young's modulus. In the study, 9 treatments were performed as randomised complete block design with 5 replications. The characteristics were determined at three moisture levels: 10%, 15%, and 20% wet basis, three loading rates: 5, 10, and 15 mm/min, and free internodes: the first, second, and third internodes. The results showed that both the bending stress and Young's modulus decreased with an increase in the moisture content and towards the third internode position. The average bending stress was obtained as 8.41 MPa varying from 6.32 to 12.41 MPa, while the average Young's modulus was calculated as 473.88 MPa ranging from 330.94 to 618.91 MPa. As shown by the results obtained, the values of the characteristics increased with increasing loading rate. |
Effect of cutting regime on soil physical properties of wet thistle meadowsOriginal PaperRenata DUFFKOVÁ, Tomáš KVÍTEKSoil & Water Res., 2009, 4(3):104-115 | DOI: 10.17221/43/2008-SWR Changes of selected soil physical properties (porosity P, soil organic matter SOM, bulk density ρd, particle density ρz, characteristics of water retention capacity - maximum capillary water capacity θCMC, and non-capillary porosity Pn) of permanent grassland (wet, non-fertilized, thistle meadows ass. Angelico-Cirsietum palustris, crystalline complex area, Czech Republic) in the top soil layer (3-10 cm) managed under three regimes (uncut UC; cut once a year C1; cut twice a year C2) were monitored for one undrained and two drained sites. There were no significant differences in selected soil physical properties among the test plots at the beginning of the study. As the intensity of utilisation decreased, the values of P, SOM, and Pn increased and ρd, ρz and θCMC decreased. Within 5-10 years of the beginning of the study, average values were: P at UC = 70, C1 = 69, C2 = 67%; SOM at UC = 10.7, C1 = 10.6, C2 = 10.0%; ρd at UC = 0.76, C1 = 0.79, C2 = 0.84 g/cm3; ρx at UC = 2.53, C1 = 2.55, C2 = 2.56 g/cm3; θCMC at UC = 50, C1 = 53, C2 = 51%; Pnat UC = 21, C1 and C2 = 16%. Moderate negative dependence of both ρx and ρd on SOM and of ρd on Pn and a moderate positive dependence of P on SOM was observed. θCMC changes did not show links to other soil physical properties. The greatest looseness of the top soil layer, expressed by a decrease in ρd, occurred with the UC regime in direct correlation with SOM, Pn and P. |
Determination of volatile organic compounds in the crude and heat treated amaranth samplesM. Ciganek, B. Pisarikova, Z. ZralyVet Med - Czech, 2007, 52(3):111-120 | DOI: 10.17221/1869-VETMED The present study concentrated on the development of an analytical method for determination of emissions of volatile organic compounds from crude and heat treated amaranth (genus Amaranthus L.) samples. Emitted substances were collected by solid-phase microextraction (SPME) method and identified by gas chromatography with mass spectrometry. The list of identified abundant organic compounds exceeds one hundred substances of different classes. Total concentrations of quantified volatile organic compounds ranged between 2.2 and 68.9 μg/g of dried sample. Hexanal and acetic acid were found as the most abundant compounds detected in amaranth samples. It was found that heat treatment (popping) of amaranth samples changed their composition of volatile organic compounds dramatically. The highest volatile organic compound emissions were found in popped grain amaranth in comparison to all crude grains and amaranth biomasses. |
Analysis of clinical and perioperative findings in 576 horses subjected to surgical treatment of colicJ. Mezerova, Z. Zert, R. Kabes, L. OttovaVet Med - Czech, 2008, 53(1):29-42 | DOI: 10.17221/1933-VETMED Colic was treated surgically in 576 horses (545 individuals). Twenty-seven horses were subjected to surgery twice and two horses three times during the period of this study. A total of 371 horses (64.4%) were discharged from the hospital, 205 animals (35.6%) died or were euthanised; 16 of them died during anaesthesia, 102 horses were subjected to euthanasia during surgery, 24 patients did not recover from anaesthesia after surgery completion, and 63 horses did not survive the postoperative period. Ileus of the small intestine was diagnosed in 267 cases (46.4%), affection of the large colon in 239 cases (41.5%), lesion of the small colon in 22 cases (3.8%), lesion of the caecum in 19 cases (3.3%), and affection of stomach and rectum in four and one cases, respectively. In 14 animals (2.4%), lesions were located at two different sites of the gastrointestinal tract. In four horses, the cause of colic was located outside the gastrointestinal tract. Three animals were affected by diffuse peritonitis. No gastrointestinal lesion could be identified during surgery in three horses with recurrent colic. The most common causes of small intestine ileus included incarceration in inguinal hernia (50 of 267 horses, 18.7%), hernia of the omental foramen (31 of 267 horses, 11.6%), anterior enteritis (19 of 267 horses, 7.1%), mesenterial volvulus (18 of 267 horses, 6.7%), and ileal impaction (18 of 267 horses, 6.7%). The most common caecal disorder was acute constipation/dysfunction (5 of 19 horses, 26.3%). Frequent causes of the large colon colic were torsion (63 of 239 horses, 26.4%), left dorsal displacement (36 of 239 horses, 15.1%), and right dorsal displacement (23 of 239 horses, 9.6%). The small colon was most often affected by focal obstruction/constipation (9 out of 22 horses, 40.9%). Surgical treatment of colic of the small intestine, caecum, large colon, and small colon was successful in 59.6%, 36.8%, 73.3%, and 63.6% of the cases, respectively. |
Exogenous chemical substances in bird perception: a reviewJ. RajchardVet Med - Czech, 2008, 53(8):412-419 | DOI: 10.17221/1926-VETMED The perception of exogenous chemical substances, olfactory navigation and the use of the olfactory sense by birds to search for food are reviewed. Many results suggest that the olfactory sense is one of the important components of the navigation system in birds. The olfactory mechanisms used by homing pigeons to navigate homeward from distant sites have been well studied. The scent of potential food, carcasses, is a positive attracting percept for Vultures. Procellariiform seabirds (petrels, albatrosses and shearwaters) are able to localize food sources by using their olfactory sense. Procellariforms are sensitive to scented compounds associated with their primary prey: krill-related odors (pyrazines and trimethylamine), odors associated with phytoplankton (dimethyl sulfide - DMS) and ammonia. Anting is a specific type of behavior of over 200 bird species. Birds probably use anting to control ectoparasites, inhibit the growth of fungi or bacteria, to soothe skin irritated during the molting period, and to remove toxic formic acid from ants prior to their consumption. Insectivorous birds react to insect malodorous substances, produced by insect groups as a chemical defense against predators. |
The effect of kaolin feeding on efficiency, health status and course of diarrhoeal infections caused by enterotoxigenic Escherichia coli strains in weaned pigletsM. Trckova, H. Vondruskova, Z. Zraly, P. Alexa, J. Hamrik, V. Kummer, J. Maskova, V. Mrlik, K. Krizova, I. Slana, L. Leva, I. PavlikVet Med - Czech, 2009, 54(2):47-63 | DOI: 10.17221/5/2009-VETMED The purpose of the present study was to assess the effect of kaolin feeding on health status, body weight gain (BWG), course of diarrhoeal infections caused by enterotoxigenic strains of Escherichia coli (ETEC) and the level of mycobacterial contamination in weaned piglets. The testing was performed in two experiments involving 40 weaned piglets at the age of 28 days. In the infection-free experiment, piglets were fed a diet without (C0) or with 1% content of kaolin (K0) for 20 days. Subsequently, all of them were fed the same diet without kaolin supplementation for 39 days. Identical diets were fed during the infection experiment, and moreover, both groups (CI and KI) were orally infected with ETEC (O141:F18ac, STa+) on Day 1 of experiment. The short-term feeding of kaolin to weaned piglets had a significant positive effect on their BWG. During the period of feeding the kaolin-containing diets, BWG in C0 and K0 were 0.20 and 0.29 kg, respectively (P < 0.05), and in CI and KI 0.13 and 0.19 kg, respectively (P < 0.05). There was no evidence of side effects to their health, neither was there any change in biochemical and haematological profiles. In the infection experiment, a protective effect of kaolin on the course of ETEC infection was evident. Colonization and shedding of ETEC by piglets fed the kaolin diet were milder and had a shorter duration in comparison with control piglets. The culture examination of pure kaolin and kaolin containing diets for mycobacteria were negative. Potentially pathogenic mycobacteria occurring in the environment were isolated from faeces and tissues of pigs. According to these results, supplementation of diets with 1% kaolin to prevent diarrhoea in piglets and to support their growth in the critical post-weaning period could be recommended. |
Altered plasma triglyceride-rich lipoproteins and triglyceride secretion in feed-restricted pregnant ewesA. Mazur, M. Ozgo, Y. RayssiguierVet Med - Czech, 2009, 54(9):412-418 | DOI: 10.17221/77/2009-VETMED In late pregnancy, energy deficits in ewes can induce a metabolic imbalance, which often results in pregnancy toxaemia. This metabolic disorder is characterised by hypoglycaemia, hyperketonaemia, an increase in plasma concentrations of free fatty acids and by fatty infiltration in the liver. The purpose of the present study was to identify alterations in lipid and triglyceride-rich lipoprotein distribution and to evaluate triglyceride secretion in ewes during the third trimester of pregnancy, particularly in ewes with feed restriction. The study was performed on non-pregnant and on twin- and triplet-bearing pregnant Limousine × Romanov ewes fed a control or restricted diet. We show that in pregnant ewes, feed restriction resulted in strong lipomobilisation, as monitored by high plasma free fatty acid concentration, and in hypoglycaemia and hyperketonaemia. Plasma and very low density lipoprotein (VLDL) triglyceride concentrations were about four-fold higher in adequately-fed pregnant ewes than in non-pregnant ewes. Feed restriction in pregnant ewes resulted in VLDL triglyceride concentrations that were approximately two-thirds lower than in adequately-fed pregnant ewes. VLDL particles from pregnant ewes were found to be enriched in triglycerides, but to a lesser extent in feed-restricted pregnant ewes. Pregnant ewes that were fed an adequate diet exhibited greater triglyceride secretion rates (TGSR) than non-pregnant ewes. Feed restriction in pregnant ewes resulted in triglyceride secretion rates that were approximately 35% lower than those of pregnant ewes fed an adequate diet. Our results support the idea that exacerbated lipomobilisation in late pregnancy leads to profound lipid and lipoprotein metabolism disturbances. |
BVDV control program in Austria - is a monitoring of the BDV status in sheep in Austria necessary?R. Krametter-Froetscher, V. Benetka, K. Rasser, F. Tockner, G. Moesslacher, K. Moestl, W. BaumgartnerVet Med - Czech, 2009, 54(11):517-524 | DOI: 10.17221/125/2009-VETMED In cattle referred to the Clinic of Ruminants at the University of Veterinary Medicine Vienna by local veterinarians from Lower Austria, the number of animals positive for antibodies against pestiviruses decreased from 11.9% in 2004 to 7.4% in 2007. In other Austrian regions the seroprevalence of 17.6% in 2004 dropped to 12.2% in 2007. The seroprevalence rates were considerably higher in older animals than in younger indicating a marked decrease of new infections (8.2% in < 1.5 years old animals, 6.8% in 1.5-4.5 years, 19.8% in 4.5-7.5 years and 33.3% in > 7.5 years). These data nevertheless also demonstrate that new pestivirus infections occur, although at a lower rate. We report the case of a calf persistently infected with Border disease virus-3 (BDV-3) detected in a mixed cattle and sheep farm with the status "BVDV-free". Earlier investigations have shown that BDV-3 is endemic in Austrian sheep populations and seems to be a potential risk factor for the reintroduction of pestiviruses in BVDV free cattle herds. Serological findings among the investigated sheep population showed in four out of nine sheep samples considerably higher titres to the BDV strain Moredun than to the BVDV strain NADL. Seroconversion against pestiviruses was also detected in contact cattle and the mother of the persistently infected calf. Pestivirus specific RNA was neither detected in the blood samples collected from the patients of the Clinic for Ruminants nor in the sheep or cattle investigated on the farm described. |
Teschen disease (Teschovirus encephalomyelitis) eradication in Czechoslovakia: a historical reportV. KoubaVet Med - Czech, 2009, 54(11):550-560 | DOI: 10.17221/163/2009-VETMED Teschen disease (previously also known as Klobouk's disease), actually called Teschovirus encephalomyelitis, is a virulent fatal viral disease of swine, characterized by severe neurological disorders of encephalomyelitis. It was initially discovered in the Teschen district of North-Eastern Moravia. During the 1940s and 1950s it caused serious losses to the pig production industry in Europe. The most critical situation at that time, however, was in the former Czechoslovakia. A nationally organized eradication programme started in 1952. That year the reported number of new cases of Teschen disease reached 137 396, i.e., an incidence rate of 2 794 per 100 000 pigs, in 14 801 villages with 65 597 affected farms, i.e., 4.43 affected farms per village and 2.10 diseased pigs per affected farm. The average territorial density of new cases was 1.07 per km2. For etiological diagnosis histological investigation of the central nervous system, isolation of virus and seroneutralization were used. Preventive measures consisted in feeding pigs with sterilized waste food and in ring vaccination. Eradication measures took the form of the timely detection and reporting of new cases, isolating outbreak areas, and the slaughter of intrafocal pigs followed by sanitation measures. Diseased pigs were usually destroyed in rendering facilities. The carcasses of other intrafocal pigs were treated as conditionally comestible, i.e., only after sterilization. During the years 1952-1965 from a reported 537 480 specifically diseased pigs 36 558 died; i.e., Teschen disease mortality rate was 6.80% while other intrafocal pigs (88.12%) were urgently slaughtered. During the whole eradication programme there were a reported 542 971 Teschen disease cases. The disease was found mainly in small private farms where domestic refuse was used for pig feeding without proper sterilization. During 1959-1972 there were a reported 16 981 529 vaccinations using a vaccine of national origin. The ratio of vaccination to national pig population was reduced from 0.4904 in 1959 to 0.0786 in 1972. During 1959-1965 the ratio of reported vaccinations to reported new diseased pigs was 521 : 1 and during 1960-1965 the ratio of reported vaccinations to reported intrafocal pigs was 85 : 1. After eradication the vaccination was stopped. The last cases were detected in 1973 and from that time Czech and Slovak territories have been free from this dangerous infection. |
Susceptibility of bacteria of the Enterococcus genus isolated on Lithuanian poultry farmsM. Ruzauskas, R. Siugzdiniene, V. Spakauskas, J. Povilonis, V. Seputiene, E. Suziedeliene, R. Daugelavicius, A. PavilonisVet Med - Czech, 2009, 54(12):583-588 | DOI: 10.17221/44/2009-VETMED The aim of this study was to test and analyse the antimicrobial susceptibility of Enterococcus isolates from Lithuanian poultry farms. Investigations were carried out during the years 2008-2009. The sampling sites, located all over the country, included eight poultry farms of large capacity. All samples were collected from broilers. Enterococcus spp. were isolated from intestines immediately after slaughtering. A total of 160 samples were collected, 20 samples from each farm. The MICs (Minimum Inhibitory Concentrations) of eleven antimicrobial agents were determined for each of the isolates using the broth microdilution method with specific microtitre plate panels (Trek Diagnostic Systems, Inc.). Susceptibility according to clinical breakpoints of chloramphenicol, linezolid, erythromycin, penicillin, quinupristin/dalfopristin, tetracycline, vancomycin, ciprofloxacin and nitrofurantoin was evaluated. One hundred and forty seven samples (92%) from a total of 160 tested samples were positive for Enterococcus spp., however, only 74 strains were selected as non-duplicate isolates. The most predominant species were identified as E. faecium (38%), E. faecalis (17.5%), E. gallinarum (12%) and E. casseliflavus (12%). The most frequent resistance properties were resistances to tetracycline (75.6%), erythromycin (56.8%) and ciprofloxacin (41.9%). No strains resistant to vancomycin and linezolid were found. High percentages of susceptibility to chloramphenicol (82.4%) and penicillin (71.6%) were also observed. A high MIC of tigecycline (≥ 1 mg/l) to 12.2% of enterococci was determined during this study. 44.6% of tested strains had a high MIC (≥ 64 mg/l) to tylosin. There was no significant correlation found between resistances of different species to different antimicrobial agents in vitro. |
Organisational culture: A study of selected organisations in the manufacturing sector in the NCRAnu SINGH LATHER, Janos PUSKAS, Ajay KUMAr Singh, Nisha GUPTAAgric. Econ. - Czech, 2010, 56(8):349-358 | DOI: 10.17221/63/2010-AGRICECON The main objective of the study is to compare the organisational culture of the selected companies in the manufacturing sector and to identify and measure the perceived organisational culture and its various dimensions. 70 responses to a 4 point scale questionnaire based on the OCTAPACE profile developed by Udai Pareek were obtained from 2 organisations in the NCR. The result shows that the executives and non- executives perceive the culture differently. The study helps in identifying the weaker aspects of culture in terms of values and beliefs that prevail in the organisation. Once the diagnosis of the culture is done to identify how much each item is valued, the management gets an opportunity to work upon the identified weaker aspects, on the basis of the degree of correlation between the various elements of the OCTAPACE profile for developing and maintaining a better organisational culture to achieve the desired performance and to sustain competition in the long run. |
Structural changes in the German agri-food complex: the end of small and medium enterprises?Miroslava BAVOROVÁAgric. Econ. - Czech, 2010, 56(12):591-600 | DOI: 10.17221/9/2010-AGRICECON The article describes the concentration process, structural changes and competitiveness in the German agri-food sector over the last decade. This descriptive analysis aims to outline the developments at the individual stages of the food chain and to identify the challenges the sector will face in the upcoming years. The study is based mainly on the data published by the German Statistical Office and the ZMP1, and the evaluation of the primary and secondary literature sources. The data shows that small and medium-sized enterprises were sustainable alongside the large ones and have played an important role in the German agriculture and food processing sectors in the recent years. Various business strategies can be expected to make the coexistence of small and large-scale enterprises also possible in the future. |
Effects of the Common Agricultural Policy potential scenarios after 2013 in the Slovak RepublicEva UHRINČAŤOVÁAgric. Econ. - Czech, 2011, 57(1):27-34 | DOI: 10.17221/144/2010-AGRICECON The contribution presents the modelling solution of the potential scenarios impact of the Common Agricultural Policy of the European Union after 2013 in the selected sectors of the Slovak Republic national economy. The solution is accomplished using the Computable General Equilibrium model with the emphasis on the productive and less favourable agricultural areas and the theoretical rents for agricultural land. If we take into consideration both pillars of the Common Agricultural Policy of the European Union, according to the modelling calculations in Slovak conditions the most favoured is the Conservative scenario, the Reference and the Flat Rate scenario are neutral and the least favourable is the Liberalisation scenario. |
International debts of developing countriesVladimír JENÍČEKAgric. Econ. - Czech, 2011, 57(2):57-63 | DOI: 10.17221/120/2010-AGRICECON The problem of international debts is, by its character, one of the most complex problems which the world economy is now facing. It complicates both the global balance of payments and the financial - credit system stability, with pronounced negative impacts on the currency stabilisation. It hinders the development of international economic co-operation and its higher forms - international economic integration. It is one of the reasons that the symmetrical forms of interdependence are pushed off and displaced by the asymmetrical ones. The global debts problem deteriorates, namely during the last time in interaction with the negative manifestations of the global problems (for example, at present very strongly with the environmental problems), the complex international co-operation climate. |
Economic results of agricultural enterprises in 2009F. Střeleček, J. Lososová, R. ZdeněkAgric. Econ. - Czech, 2011, 57(3):103-117 | DOI: 10.17221/175/2010-AGRICECON Every year, an analysis of economic results of a sample of agricultural enterprises farming in various production and climatic conditions in the territory of the Czech Republic is carried out by applying economic statistical methods. Based on these results, long-term trends of economic results and their influencing factors are defined. This article is based on the analysis of development of economic indicators of a sample of agricultural enterprises in the Czech Republic in the period 2003-2009, divided according to the proportion of the LFA. The year 2009 brought, in comparison with the previous years, a strong deterioration in economic results. In 2009, the economic result was the worst during the whole monitored period. The decrease in the average number of workers together with the increase in labour productivity manifests a long-term tendency. Agricultural subsidies tend also to grow in the long-term even though their growth has been slowing down. |
