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Results 3691 to 3720 of 4599:

Occurrence of Alternaria toxins in fibre flax, linseed, and peas grown in organic and conventional farms: Monitoring pilot study

Jana Králová, Jana Hajšlová, Jan Poustka, Miroslav Hochman, Marie Bjelková, Lenka Odstrčilová

Czech J. Food Sci., 2006, 24(6):288-296 | DOI: 10.17221/3327-CJFS

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.

Changes in the macrocomponents and microstructure of white bean seeds upon mild hydrothermal treatment

Maria Soral-Śmietana, Urszula Krupa

Czech J. Food Sci., 2005, 23(2):74-83 | DOI: 10.17221/3375-CJFS

The mild hydrothermal treatment (water bath at 40°C/24 h) of three Polish bean varieties (Phaseolus vulgaris and Phaseolus coccineus) with different sizes of seeds: the small-seed variety Raba, the medium-seed variety Aura, the large-seed variety Eureka, had a significant effect on the microstructure of the cross-sections of bean cotyledons. The first 3 hours were decisive with almost all physical and chemical parameters investigated in the study. After this time, the highest water binding or water holding capacities were observed. The tendency to a distinct decrease in the resistant starch fraction was observed especially in the large and medium bean seeds (Phaseolus sp.), based on the comparison before and after the processing. It seems that the too high dietary fibre content determined in the study resulted from exceptional sorption properties while the especially high increase in the insoluble fraction of dietary fibre (IDF) was observed during this mild hydrothermal treatment. This suggests the possibility of the occurrence of hydrophilic domains in dietary fibre. Although it cannot be explained explicitly, distinct differences were found in both fractions of dietary fibre in the varieties examined. The results obtained indicate that the conditions of the mild hydrothermal treatment can affect the nutritional and non-nutritional components of bean seeds which play an important role in the human gastrointestinal tract as both food products and diet components.

A study of the factors affecting the foaming properties of egg white - a review

Kateryna Lomakina, Kamila Míková

Czech J. Food Sci., 2006, 24(3):110-118 | DOI: 10.17221/3305-CJFS

Many foods are prepared using egg white, most of them being based on the foaming properties of egg white which are due to albumen proteins ability to encapsulate and retain air. Therefore, many scientists aim to find new methods to improve the volume and the stability of egg white foam. This paper is a review of various factors affecting the foaming ability of egg white.

Grains of Nontraditional Crops as Sources of Retrograded Resistant Starch

D Mikulíková, I Čičová, G Antalíková, J Kraic

Czech J. Genet. Plant Breed., 2005, 41(3):96-104 | DOI: 10.17221/3667-CJGPB

The content of retrograded resistant starch of the RS3 type was determined in six plant species and their accessions. Besides sorghum and foxtail millet, plant genotypes were cultivated in Piešťany locality in the year 2003. There were significant differences in RS3 and total starch content in analysed crops and their accessions. Chickpea and buckwheat had the highest average content of RS3, 5.2% and 3.8%, respectively. Millet and foxtail millet contained less RS3, 2.9% and 2.8%, respectively. Millet was rich in total starch. The lowest amounts of RS3 were detected in sorghum (1.6%) and amaranth (1.2%). The lowest variation in the RS3 content was detected within the set of millet accessions and the highest within amaranths.

The effect of liming on cadmium, lead, and zinc uptake reduction by spring wheat grown in contaminated soil

P. Tlustoš, J. Száková, K. Kořínek, D. Pavlíková, A. Hanč, J. Balík

Plant Soil Environ., 2006, 52(1):16-24 | DOI: 10.17221/3341-PSE

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.

Biosynthesis of food constituents: Amino acids. 3. Modified proteinogenic amino acids - a review

Jan Velíšek, Karel Cejpek

Czech J. Food Sci., 2006, 24(2):59-61 | DOI: 10.17221/3300-CJFS

This review article gives a survey of principal pathways that lead to the biosynthesis of the modified principal proteinogenic amino acids, i.e. cystine, 4-hydroxyproline, 5-hydroxylysine, 3-methylhistidine, and O-phosphoserine. Except the proteinogenic amino acids, peptides and proteins often contain several unusual amino acids arising by specific modifications (e.g. oxidation or esterification) of amino acid residues present in the already synthesised polypeptide chain. The post-translational products include, e.g., the oxidation of the thiol groups of two cysteine residues to form a disulfide bridge (cystine), thus allowing cross-linking of polypeptide chains; the hydroxylation of proline to 4-hydroxyproline and of lysine to 5-hydroxylysine; N-methylation of histidine to 3-methylhistidine; and the phosphorylation of serine to O-phosphoserine. There also exist several other modified proteinogenic amino acids that are of minor significance to foods.

Biosynthesis of food constituents: Lipids. 1. Fatty acids and derivated compounds - a review

Jan Velíšek, Karel Cejpek

Czech J. Food Sci., 2006, 24(5):193-216 | DOI: 10.17221/3317-CJFS

This review article gives a survey of the principal biosynthetic pathways that lead to the most important common fatty acids and their derivatives occurring in foods and feeds. Fatty acids are further subdivided to saturated fatty acids and unsaturated fatty acids. This review is focused on the less common fatty acids including geometrical and positional isomers of unsaturated fatty acids, acetylenic fatty acids, branched-chain fatty acids, alicyclic fatty acids, epoxy fatty acids, hydroxy fatty acids, and oxo fatty acids. A survey is further given on the biosynthesis of the aliphatic very-long-chain components (alkanes, primary and secondary alcohols, aldehydes, ketones, and esters) of plant cuticular wax derived from saturated fatty acids. Subdivision of the topics is predominantly via biosynthesis. There is extensive use of reaction schemes, sequences, and mechanisms with enzymes involved and detailed explanations using chemical principles and mechanisms.

Changes in the zinc content in the meadow sward under conditions of a long-term static fertilizer experiment (Czarny Potok)

M. Kopeć

Plant Soil Environ., 2005, 51(9):410-415 | DOI: 10.17221/3605-PSE

Changes in the zinc content in the meadow sward were studied in a long-term fertiliser experiment set up on a mountain meadow (20°54'E, 49°24'N) in 1968. The experiment is localized at 720 meters above sea level on the soil which belongs to Dystric Cambisols and comprises 8 fertiliser treatments in two series: 0Ca and + Ca (Table 1). In the course of the experiment the Zn content in the sward decreased and the time factor was of greater consequence than fertilization, P content in the sward or soil and acidification. In mountain meadow communities shaped by a long-term (over 30 years) NPK treatment and at yields between 6.7 and 7.1 t/ha the annual quantity of absorbed Zn ranged between 233 and 256 g Zn/ha dry weight. During the experimental period the biggest amount of Zn removed with the sward yield exceeded 500 g Zn/ha annually. In the limed series at slightly bigger yields the quantity of Zn removed with the yield was over 10% lower in objects receiving NPK fertilization than on the same treatments in the unlimed series. Liming is able to reduce soil Zn abundance.

Comparison of in vitro gas production technique with in situ nylon bag technique to estimate dry matter degradation

A. Kamalak, O. Canbolat, Y. Gurbuz, O. Ozay

Czech J. Anim. Sci., 2005, 50(2):60-67 | DOI: 10.17221/3996-CJAS

Dry matter (DM) degradation of wheat straw (WS), barley straw (BS), lucerne hay (LH) and maize silage (MS) was determined using two different techniques: (i) in vitro gas production and (ii) nylon bag degradability technique. In vitro gas production and in situ DM disappearance were measured after 3, 6, 12, 24, 48, 72 and 96 hours of incubation. In situ and in vitro DM degradation kinetics was described using the equation y = a + b (1 - ect). In all incubations there were significant (P < 0.001) correlations between gas production and in situ DM disappearance or estimated parameters ((a + b)gas and (a + b)is or (a + b)gas and EDMDis) whereas there were no significant (P > 0.05) correlations between cgas and cis or bgas and bis. Gas production from the insoluble fraction (b) alone explained 98.3% of the variation of EDMD. The inclusion of gas production from the quickly soluble fraction (a) and rate constant (c) of gas production in the regression equation improved the accuracy of EDMD prediction. The correlations between the results of both methodologies seem to be sufficiently strong to predict degradability parameters from gas production parameters. It was concluded that the in vitro gas production technique has good potentiality to predict in situ DM disappearance and some DM degradation parameters.

Mapping spatial variability of soil properties and yield by using geostatic method

M. Kroulík, M. Mimra, F. Kumhála, V. Prošek

Res. Agr. Eng., 2006, 52(1):17-24 | DOI: 10.17221/4875-RAE

The Czech University of Agriculture in Prague (CUA) Farm at Lány started with precision farming technology several years ago. In the first step the yield and nutrients content were monitored. For precision application development, detailed description of soil conditions and interrelationship will be necessary. Pulling force and soil electric conductivity measurement as indirect measuring methods were used for mapping spatial soil variability. These methods demonstrate other ways for description of complex soil media.

Biosynthesis of food constituents: Peptides - a review

Jan Velíšek, Roman Kubec, Karel Cejpek

Czech J. Food Sci., 2006, 24(4):149-155 | DOI: 10.17221/3311-CJFS

This review article gives a brief survey of principal pathways that lead to the biosynthesis of most important peptides occurring in foods. Glutathione, selected plant γ-glutamyl peptides, and animal histidine dipeptides are included in this review.

Description of morphological characters of wild Lactuca L. spp. genetic resources (English-Czech version)

I. Doležalová, E. Křístková, A. Lebeda, V. Vinter

Hort. Sci. (Prague), 2002, 29(2):56-83 | DOI: 10.17221/4461-HORTSCI

Of about 100 Lactuca species, there are only 22 represented in world gene bank collections. The description of morphological and other important features of wild lettuce accessions and a correct taxonomic ranging increase their potential successful utilization. A broad study of 22 wild Lactuca species, their morphology, anatomy, karyology, DNA content and isozyme variation, and a search of large number of literature sources (description keys, floras, monographs) provided a base for an elaboration of a descriptor set. This set consists of 88 descriptors and 24 of them are elucidated by figures. It provides a tool for Lactuca species characterization and determination and for a discrimination of an infraspecific variation. Obtained data can be used for description of wild Lactuca genetic resources and also for research purposes.

Antimutagenic effect of genistein

Zdeňka Polívková, Martina Langová, Petr Šmerák, Jiřina Bártová, Ivo Bárta

Czech J. Food Sci., 2006, 24(3):119-126 | DOI: 10.17221/3306-CJFS

A great variety of health benefits including the protection against breast and prostate cancers has been attributed to the soya consumption, because of the presence of soy beans isoflavones, genistein, and others. We investigated the antigenotoxic effect of genistein on the genotoxicity of three mutagens and carcinogens - aflatoxine B1 (AFB1), 2-amino-3-methylimidazo [4,5-f]quinoline (IQ), and N-nitroso-N-methylurea (MNU), using the Ames bacterial mutagenicity test and the micronucleus test. In the Ames test on Salmonella typhimurium, a significant antimutagenic effect was determined against the indirect mutagen AFB1 in two strains, TA98 and TA100. However, the effect on the IQ indirect mutagenicity was more pronounced in the test with TA98 than with TA100. The mutagenicity of the direct mutagen MNU was suppressed by genistein only at its highest concentration used (300 µg/plate). The protective effect of genistein against all three mutagens was proved in the micronucleus test as the treatment of mice with the combinations of genistein and mutagens resulted in a significant reduction of the number of micronuclei in comparison with the number of micronuclei induced by the individual mutagens alone.

Genetic and Physical Mapping of Genic Microsatellites in Barley (Hordeum vulgare L.)

R K Varshney, U Hähnel, T Thiel, N Stein, L Altschmied, P Langridge, A Graner

Czech J. Genet. Plant Breed., 2005, 41(4):153-159 | DOI: 10.17221/3661-CJGPB

Due to the availability of sequence data from large-scale EST (expressed sequence tag) projects, it has become feasible to develop microsatellite or simple sequence repeat (SSR) markers from genes. A set of 111 090 barley ESTs (corresponding to 55.9 Mb of sequence) was employed for the identification of microsatellites with the help of a PERL5 script called MISA. As a result, a total of 9 564 microsatellites were identified in 8 766 ESTs (SSR-ESTs). Cluster analysis revealed the presence of 2 823 non-redundant SSR-ESTs in this set. From these 754 primer pairs were designed and analysed in a set of seven genotypes including the parents of three mapping populations. Finally, 185 microsatellite (EST-SSRs) loci were placed onto the barley genetic map. These markers show a uniform distribution on all the linkage groups ranging from 21 markers (on 7H) to 35 markers (3H). The polymorphism information content (PIC) for the developed markers ranged from 0.24 to 0.78 with an average of 0.48. For the assignment of these markers to BAC clones, a PCR-based strategy was established to screen the "Morex"-BAC library. By using this strategy BAC addresses were obtained for a total of 127 mapped EST-SSRs, which may provide at least two markers located on a single BAC. This observation is indicative of an uneven distribution of genes and may lead to the identification of gene-rich regions in the barley genome.

Game damage to forest trees

V. Malík, P. Karnet

J. For. Sci., 2007, 53(9):406-412 | DOI: 10.17221/2143-JFS

Humans should behave in such a way that they will not endanger the existence of other living entities. After all, human activities affected the tree species composition and wildlife living conditions. Humans are now responsible for the preservation of delicate equilibrium in nature. Two localities were chosen for the research of game damage caused to standing trees - shooting areas Lužánky and Červený jelen, both situated in the vicinity of Jindřichův Hradec in South Bohemia. Seasonal character of tree-damage origin as well as its relation to the chemical content of spruce (Picea abies [L.] Karst.) and pine (Pinus sylvestris [L.]) bark were investigated. This area is typical of high game stock; trees are damaged by browsing and bark stripping. Particular advice for game management with respect to minimizing tree damage is presented. The data set of chemical bark analyses was statistically evaluated by t- and F-test and significant differences in element contents were detected between damaged and undamaged pine bark for N-substances (P = 0.003309), Ca (P = 0.001460), P (P = 0.004343), Mg (P = 0.001419) and K (P = 0.016290). Humans have influenced many changes in the distribution of different animal and plant species. Among others they are responsible for the altered species composition. Typically the extinction of large predators produces changes in food chains. In forest stands influenced by human activities the reasonable game management and the regulation of game stock seems to be one of the main tools in forest protection.

World commodity trade in the globalisation processes

V. Jeníček

Agric. Econ. - Czech, 2007, 53(3):101-110 | DOI: 10.17221/454-AGRICECON

The real trade development is estimated by the recalculation of nominal value through unit values (prices). The unit value indices reflect, besides the change of prices, also the changes in the structure and qualitative changes of the traded products. In the 70s, the average yearly increase of unit values reached 14% and reflected namely the inflation caused by the oil shocks. Since then, it reaches in average up to 1%. We can suppose that, under the normal conditions, unit values growth is rather the consequence of the qualitative and structural changes (increased share of the more sophisticated products of processing industry), in fact, prices in international trade have been decreasing for years already. The question whether the world trade growth rates decrease or accelerate is then still open. It is certain that the world trade volume growth rate (6.3%) has shown a considerable surpass to the production growth rate (4.1%).

Comparative analysis of small and medium-sized enterprises in the Czech Republic

R. Zuzák, E. Jirkovská

Agric. Econ. - Czech, 2007, 53(10):479-482 | DOI: 10.17221/1218-AGRICECON

The contribution presents the findings of the third phase of an extensive survey, the main goal of which was the identification of factors stimulating or restricting the establishment of small and medium-sized enterprises. It comprises the outcomes of the comparative analysis aimed at the comparison of groups of small and medium-sized enterprises and the model enterprise according to areas influencing founders' entrepreneurial activities.

Effect of soil applied herbicides and depth of sowing on common cocklebur (Xanthium strumarium L.) and maize (Zea mays L.) emergence and early growth

Zvonko Pacanoski, Tasko Kostov, Gordana Glatkova, Branislav Knežević

Plant Protect. Sci., 2007, 43(3):117-121 | DOI: 10.17221/2246-PPS

Greenhouse trials were conducted during 2005 to investigate the effect of six soil applied herbicides on common cocklebur (Xanthium strumarium L.) sowed at a depth of 4 cm and 7 cm, and determine the potential injury to maize by the herbicides and the influence of sowing depths. The efficacy of all herbicides was high, regardless of sowing depth and, generally, the coefficient of efficacy ranged from 86.3% to 100.0%. Most of the herbicides had no significant phytotoxic effect on maize plant density/container, height and fresh weight of maize. Exceptions were Atranex-90WDG and Cyatral-SCZ, which caused serious injury to maize (33% and 37%, respectively) if seeded at a depth of 7 cm, and significantly reduced height and fresh weight of the plants.

Commercial phenotypic tests (API 20E) in diagnosis of fish bacteria: a review

N. Topic Popovic, R. Coz-Rakovac, I. Strunjak-Perovic

Vet Med - Czech, 2007, 52(2):49-53 | DOI: 10.17221/2058-VETMED

The available data concerning rapid identification of fish bacteria via commercial phenotypic tests demonstrate that there is no agreement regarding the choice of the tests. However, API 20E, an identification system for Enterobacteriaceae and other non-fastidious Gram-negative rods developed for clinical specimens, seems to be increasingly used for the identification of fish pathogens. In this review, adaptation of API 20E for fish bacterial isolates and its distinctiveness for fish bacteria was assessed. Some strains are wrongly identified because they are not included in the database of API 20E system. API 20E reactions should be compared with the diagnostic schemes based on reactions in conventional phenotypic tests. Due to their significance for fish health and impact on the aquaculture, and because of the need for their rapid identification, some important fish bacteria should be included in the API 20E system, such as Yersinia ruckeri, Edwardsiella ictaluri, Vibrio anguillarum.

Spatiotemporal variation of some metal concentrations in oysters from the Mali Ston Bay, south-eastern Adriatic, Croatia - potential safety hazard aspect

A. Gavrilovic, E. Srebocan, J. Pompe-Gotal, Z. Petrinec, A. Prevendar-Crnic, Z. Matasin

Vet Med - Czech, 2007, 52(10):457-463 | DOI: 10.17221/2047-VETMED

The concentrations of cadmium, lead and zinc were determined in the soft tissue of oysters (Ostrea edulis L.) from three locations in the Mali Ston Bay on the south-eastern coast of the Adriatic Sea. The sampling was performed during two periods of breeding cycle, in summer (age ~1 year) and winter (age ~20 months, consumption size). The concentrations of cadmium, lead and zinc measured in the oyster soft tissue showed considerable spatiotemporal variations that could be attributed to seasonal differences in the freshwater inflow which varied between the study locations. Median concentrations measured at different locations and in different time periods ranged from 0.303 to 0.969, 0.13 to 0.32 and 208.9 to 650.0 µg/g wet weight for cadmium, lead and zinc, respectively. Although metal concentrations do not exceed the maximal legally approved limits according to the legislation of the Republic of Croatia and EU, more knowledge of their spatiotemporal distribution - of cadmium in particular - would contribute to the sustainable future development of oyster farming in Croatian waters.

The role of Fe- and Mn-oxides during EDTA-enhanced phytoextraction of heavy metals

M. Komárek, P. Tlustoš, J. Száková, V. Chrastný, J. Balík

Plant Soil Environ., 2007, 53(5):216-224 | DOI: 10.17221/2203-PSE

In several cases ethylenediaminetetraacetic acid (EDTA) proved to be an efficient mobilising amendment during chemically enhanced phytoextraction of heavy metals. The presence of Fe-(hydr)oxides and their dissolution after the addition of EDTA can limit the phytoextraction of the targeted heavy metals due to the high stability of the formed Fe(III)EDTA complexes. This study has focused on the influence of Fe- and Mn-oxides and hydroxides dissolution on heavy metal uptake by Zea mays in a two-year EDTA-enhanced phytoextraction process. Incubation experiments and speciation modelling proved the increased concentrations of Mn and Fe through the dissolution of Mn-and Fe-(hydr)oxides. Furthermore, increased Fe and Mn accumulation was observed in maize plants after the second year of the phytoextraction process. Therefore, the presence of Mn- and especially Fe-(hydr)oxides proved to be a limiting factor during EDTA-enhanced phytoextraction of heavy metals from contaminated soils.

Effect of interactions between nickel and other heavy metals on the soil microbiological properties

J. Wyszkowska, E. Boros, J. Kucharski

Plant Soil Environ., 2007, 53(12):544-552 | DOI: 10.17221/2190-PSE

A pot greenhouse experiment was performed to determine the effect of contamination with nickel interacting with other heavy metals on the microbiological properties of soil. The study was conducted on samples of soils classified under natural conditions as typical Eutric Cambisol developed from heavy loamy sand and typical Eutric Cambisol developed from light silty loam. Soil material was contaminated with nickel in the amount of 50 and 200 mg Ni2+/kg. The treatments with 200 mg Ni2+/kg were additionally contaminated with other heavy metals (Zn2+, Cu2+, Pb2+, Cd2+, Cr6+), in the amount of 50 mg/kg soil. The following treatments, in which the soil was contaminated with heavy metals applied alone or in combinations, were compared in the study: Ni, Zn, Cu, Pb, Cd, Cr, NiZn, NiCu, NiPb, NiCd, NiCr, NiZnCu, NiZnPb, NiZnCd, NiZnCr, NiZnCuPb, NiZnCuCd, NiZnCuCr, NiZnCuPbCd, NiZnCuPbCr, NiZnCuPbCdCr. The experiment was carried out in four replications. A microbiological analysis was performed on days 28 and 56. The tested crop was oat. It was found that the impact of particular heavy metals on microbiological properties of soils depended on their type, interactions between nickel and zinc, copper, lead, cadmium and chromium (VI), date of analysis and soil species. Soil contamination with heavy metals reduced the population size of Azotobacter spp. The counts of other microbial groups, i.e. copiotrophic bacteria, spore-forming copiotrophic bacteria, oligotrophic bacteria, spore-forming oligotrophic bacteria, ammonifying bacteria, nitrogen immobilizing bacteria, cellulose-decomposing bacteria, Arthrobacter spp., Pseudomonas spp., actinomyces and fungi, showed varied susceptibility to heavy metals.

Effect of weaning system on lamb growth and commercial milk production of Awassi dairy sheep

S. Dikmen, I.I. Turkmen, H. Ustuner, F. Alpay, F. Balci, M. Petek, M. Ogan

Czech J. Anim. Sci., 2007, 52(3):70-76 | DOI: 10.17221/2357-CJAS

To determine the effect of weaning system on Awassi sheep milk production and lamb growth, 68 Awassi ewes and their lambs (n = 104) were assigned to one of the following treatment groups a) after 3 days from birth (MIX), ewes were separated from their lambs during the evening for 15 h and milked once daily in the morning, and their lambs were allowed to suckle for 9 h during the day or b) ewes were not milked and suckled by their lambs (DY60) during the first 60 days of lactation. Ewes and their lambs were assigned to the groups according to ewe's age, parturition date, sex of the lamb and birth type. All lambs were weaned at 60 days of age and the ewes were milked twice daily. Milk yield was recorded fortnightly and milk fat composition was recorded monthly. The birth weight of lambs was recorded in the first 2 hours and they were weighed fortnightly until 240 days of age. Average lactation lengths (including suckling and milking) in MIX and DY60 group were similar (171.21 ± 5.40 and 168.36 ± 4.87 days, respectively). Differences between MIX and DY60 group in commercial milk yield (103.25 ± 7.93 and 63.59 ± 5.41 kg, respectively) and milk fat yield (5.88 ± 0.64 and 3.62 ± 0.31 kg, respectively) were highly significant (P < 0.001). Growth performance of lambs was similar in both groups (P > 0.05), however, male lambs were heavier and grew faster than female lambs until weaning (P < 0.05) and 90 days of age (P < 0.001). The effect of birth type at 210 days of age for the female lambs in MIX group was found to be statistically significant (P < 0.05) and the mean weight of single born female lambs was 40.39 ± 1.27 kg, and 41.09 ± 1.22 kg for twin born female lambs. The effects of ewe's age for female lambs in MIX and DY60 group and birth type for the lambs in DY60 group were insignificant (P > 0.05). These results show that Awassi lambs can be successfully reared in MIX suckling system and ewes produce more commercial milk than in the traditional rearing system (DY60), which offers a potential increase in economic return for Awassi sheep producers.

Effect of the application of bioplexes of zinc, copper and manganese on milk quality and composition of milk and colostrum and some indices of the blood metabolic profile of cows

S. Kinal, A. Korniewicz, M. Słupczyńska, R. Bodarski, D. Korniewicz, B. Čermák

Czech J. Anim. Sci., 2007, 52(12):423-429 | DOI: 10.17221/2338-CJAS

The object of an experiment was inorganic and organic forms of zinc, copper and manganese applied in mineral mixtures to dairy cows. The experiment was carried out on 90 cows with average milk yield for previous lactation of about 9 500 kg milk. The cows received mineral mixtures containing inorganic or organic forms of zinc, copper and manganese for 6 weeks before calving and during the first three months of lactation. The application of microelements as bioplexes in amounts covering 30% of daily requirements of cows had a positive effect on an increase in colostrum dry matter content from 20.9 to 23.35% as well as on the concentration of protein and fat, and the level of minerals - calcium, phosphorus, magnesium, zinc and copper. In cows' milk in the 2nd and 3rd month of lactation there were no differences in contents of minerals. However in the blood serum of cows in the 1st and 2nd month of lactation an increase in calcium concentration from 1.96 to 2.14 g/kg was observed while the content of phosphorus also increased average from 1.76 to 2.22 g/kg in the first trimester of lactation.

Monitoring of glasshouse climatic processes with the proposal of their control

L. Holoubek, R. Kukla, R. Kadlec

Res. Agr. Eng., 2006, 52(2):48-54 | DOI: 10.17221/4879-RAE

: The aim of this project was to carry out measurements of climatic process occurring in the glasshouse. This article describes the method of measuring the glasshouse microclimate using the Control WEB 2000 software and the ADAM 4000 series input/output modules. Control WEB 2000 is a graphic development environment to create measuring and control applications. Data acquisition was made by using the ADAM modules of 4000 series which ensure the conversion of data and their transmission from the sensors to the control computer. Soil temperature, glasshouse indoor and outdoor air temperatures and air humidity were analyzed during two summer months. The measuring application is further extended by a proposal for microclimate control in the glasshouse.

Altitude and forest type effects on soils in the Jizera Mountains regionOriginal Paper

Lenka Pavlů, Luboš Borůvka, Antonín Nikodem, Marcela Rohošková, Vít Penížek

Soil & Water Res., 2007, 2(2):35-44 | DOI: 10.17221/2114-SWR

This paper is focused on the Jizera Mountains as a region strongly influenced by man in the past. The structure of the natural forest was changed. Species monocultures with similar tree ages were planted. High acidificants concentrations in atmosphere led to the decline of these monoculture forests in the top parts of the mountains and the high acidificants deposition damaged the soils in the whole region. The goals of this study are to describe the distribution of the soil properties in altitude transects, where temperature, precipitation, and vegetation gradients are recorded, and to compare the soil properties in spruce and beech forests. The soil samples were collected from soil pits in a surviving nature-close beech forest, in a production spruce forest, and also in the top dead forest area with a grass cover. Soil samples from sufficiently deep diagnostic horizons were taken for the study of chemical properties. The basic soil characteristics were determined by the commonly used methods (pH, effective cation exchange capacity - eCEC, and the contents of cations in the sorption complex, A400/A600 as humus quality parameter, the contents of available Ca, Mg, K and P, pseudototal content of Ca and Mg, and two differently extracted Fe and Al forms contents). The soils of the Jizera Mts. are strongly acid with a low eCEC which is the result of the natural and anthropogenic acidification processes. Soil chemical properties of the most affected top mountainous parts are in some aspects more favourable than lower parts (binding of potentially toxic Al in organic matter, slightly higher pH), but in other aspects they are still endangered by the acidification symptoms (higher leaching of base cations, especially Mg). The soils of nature-close beech forests represent more favourable soil properties than those of planted spruce forests. Generally, it can be concluded that the natural systems have higher resilience, and that natural mechanisms are able to mitigate slightly the soil degradation.

Biological activity of anthropogenic soils after spoil-bank forest reclamation

J. Remeš, R. Šíša

J. For. Sci., 2007, 53(7):299-307 | DOI: 10.17221/2075-JFS

The paper presents the results of relatively long-term research focused on spoil bank revitalization pro-cesses in the North Bohemian Brown Coal Basin after the first three years of observations. The biological activity of soil (namely catalase and phosphatase activity), indicators of basal and potential soil respiration, ammonification and growth, development and nutrition status of forest plantations were selected as indicators of this revitalization process. These parameters were determined in five localities of different age of reclamation where different technological approaches and tree species compositions were used. The results confirm the distinct time dependence of revitalization processes. From the aspect of biological activity older reclamations are close to natural forest soil. The enrichment of top soil layer with organic matter before the plantation (by ploughing in cellulose fibres and peat addition) increased some parameters of soil biological activity. The positive amelioration effect of black alder (Alnus glutinosa) was also confirmed.

Web-spinning sawflies of the genus Cephalcia Panzer (Hymenoptera, Pamphiliidae) in the Picea abies forests of the Beskidy Mountains (Poland)

M. Jachym

J. For. Sci., 2007, 53(20):63-68 | DOI: 10.17221/2149-JFS

This article presents a review of data and results of investigations from the period 1958-2006 regarding the occurrence of insects of the genus Cephalcia Panzer (Hymenoptera, Pamphiliidae) in Norway spruce stands of the Beskidy Mountains (Western Carpathians, southern Poland). Currently, eight species are known for the area: C. abietis, C. alashanica, C. alpina, C. annulicornis, C. arvensis, C. erythrogaster, C. fulva and C. masuttii. Information regarding each species is given, with details on identification, local occurrence and importance.

Work motivation and the municipality size

L. Kolman, P. Michálek, H. Chamoutová, K. Chamoutová, L. Müllerová

Agric. Econ. - Czech, 2007, 53(1):30-35 | DOI: 10.17221/845-AGRICECON

The article shows the results of the grant project of Czech Science Foundation 406/03/0896, which focused on the survey of work motivation and quality of working life issues in the Czech country. The results concern an analysis of variation and a range of coefficients and show statistically significant differences in motivational coefficients in sets that differ in the respondents size of residence. The main aim of the survey was to find out if it is possible to identify the differences in work motivation between people from large cities and people from small municipalities, namely between inhabitants of the Prague metropolitan area and smaller municipalities placed near to the national boundary. The survey was conducted by means of the EDMK questionnaire, which is described elsewhere (see references). Some specific questions were added by the present authors. Statistical analysis of the data obtained resulted in the findings, as follows: (1) questionnaire scales used are sufficiently reliable (as proved by the Cronbachs' alphas statistics); (2) statistically significant differences were identified in the motivational patterns of the Prague Metropolitan Area and small municipalities inhabitants; (3) the quality of working life in Czechia was found as a rather low; it results in lower perceived responsibility and job involvement found in the whole sample of Czech responses.

The comparison of agricultural support policies in the OECD and the EU countries from the perspective of economic globalization processes

P. Bielik, P. Juríček, D. Kunová

Agric. Econ. - Czech, 2007, 53(8):339-348 | DOI: 10.17221/902-AGRICECON

The paper analyses the evaluation of agricultural and farm support in the OECD countries and its differentiated development in the respective countries. This is important, because the effect of subsidies on production, trade, income as well as environment, directly depends on the way how this subsidies are disbursed to the farmers. Another object of the analysis are the differences in the level of support between different commodities that may lead to deformations.

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