Fulltext search in archive
Results 4561 to 4590 of 5824:
Lipid oxidation and quality parameters of sausages marketed locally in the town of Săo Paulo (Brazil)C.K.B. Ferrari, E.A.F.S. TorresCzech J. Food Sci., 2002, 20(4):144-150 | DOI: 10.17221/3525-CJFS Lipid oxidation constitutes one of the most important causes of the chemical deterioration of foods, especially meats. Many harmful effects on human health are associated with lipid oxidation. During a period of six weeks, samples were bought at random on city hall food markets (CHFMs) and were analysed for lipid oxidation (TBARS-test) and some quality factors - redox potential (Eh), pH and water activity (aw). The mean of Eh was X ± σn-1 = 39.03 ± 26.30 mV, ranging from -86.00 to 92.00 mV. pH mean value was X ± σn-1 = 5.97 ± 0.27, ranging from 5.08 to 6.48. Comparing the CHFMs, no statistically significant differences were observed between them in respect to pH, Eh, and aw values. TBARS mean value was X ± σn-1 = 0.44 ± 0.23 mg/kg, ranging from 0.38 ± 0.19 mg/kg (CHFM-6) to 0.58 ± 0.31 mg/kg (CHFM-2), with extreme values of 0.22 mg/kg and 1.08 mg/kg. No statistically significant correlations between TBA test values and all tested variables were detected. According to the sensorial analysis criteria of Greene and Cumuze (1981), 16.67% of sausage samples could be rejected and 11.11% revealed critical TBARS values. |
Phenolic compounds of seed coats of white and coloured varieties of pea (Pisum sativum L.) and their total antioxidant activityA. Troszyńska, E. CiskaCzech J. Food Sci., 2002, 20(1):15-22 | DOI: 10.17221/3504-CJFS The purpose of this study was to compare the composition and contents of phenolic acids and condensed tannin in the seed coats of white and coloured varieties of pea and to examine the antioxidant properties of methanol and acetone extracts containing these phenolic compounds. The contents of phenolic acids were quantified by the HPLC analysis. The sum of free phenolic acids, those liberated from soluble esters and those liberated from soluble glycosides, was higher for coloured seed coat (78.53 g per g dry matter) than for the white seed coat (17.17 g/g dry matter). Protocatechuic, gentisic and vanillic acids were found dominant in the coloured seed coat, while ferulic and coumaric acids in the white seed coat. The content of condensed tannins was 1560 mg of catechin equivalent/100 g of coloured seed coat as determined by a vanillin assay. No condensed tannins were detected in the white seed coat. The antioxidant activity of extracts was measured by the oxidation of phosphatidylcholine to hydroxyperoxidephosphatidyl choline in the liposome system. Strong antioxidant properties were observed in a crude tannin extract from the coloured seed coat. These properties were slightly changed after the seed coat was cooked in water for 30, 60 and 90 min. |
Effect of defatted soybean flour on the flavour of extruded mixtures with wheat flourJ. Pokorný, A. Farouk Mansour, F. Pudil, V. JandaCzech J. Food Sci., 2002, 20(6):229-236 | DOI: 10.17221/3535-CJFS Mixtures of wheat semolina, 5% glucose and 0-30% defatted soybean flour were used for the preparation of extruded samples using a pilot plant single screw extruder, maximum temperature being 140°C. The browning reactions were only moderate, the intensities of the trichromatic a* coordinate increased, and some changes were observed in chroma and the odour difference ΔE*. The sensory acceptability improved by increasing the content of soybean flour, the odour intensity increased, and some changes were observed in the sensory profile. Volatile substances were isolated using a SPME procedure, and the volatiles were separated using a Fisons GLC 8000 apparatus equipped with a mass spectrometer. Among the flavour active volatiles, pyrazines were the most prominent class of compounds, especially methyl and ethyl substituted derivatives. Pyrrole and furan substituted pyrazines were found only in small amounts because of the low extrusion temperature. Other furan and pyrrole derivatives had a lesser effect on flavour because of their relatively low amounts. Aldehydes, fatty acids, ketones, and other aliphatic derivatives contributed only a little to the resulting flavour. Compared to the mixtures of semolina and glucose only, the additions of defatted soybean flour moderately increased the number of substituted pyrazines detected in the extruded mixtures but increased substantially the pyrazine fraction in the total peak area. Among furan derivatives, 2-furancarboxaldehyde, 2-furanmethanol and 5-methyl-2-furyl alcohol belonged to the most prominent derivatives. Among other compounds, acetic acid, butyrolactone and maltol should be mentioned. |
Residence time distribution during egg yolk pasteurisationA. Landfeld, R. Žitný, M. Houška, K. Kýhos, P. NovotnáCzech J. Food Sci., 2002, 20(5):193-201 | DOI: 10.17221/3531-CJFS This work describes the determination of the average residence times during egg yolk - and whole liquid eggs pasteurisation in an industrial pasteurisation equipment (plate pasteuriser + tube holder). For the detection of the impulse the conductivity method was used. Conductivity was then monitored using the bridge method. In the system, the total of 3 probes were placed. To mark the particles of the flowing product, salted yolk with the content of salt of 1.3 or 1.8% was used. In addition, rheological properties of pasteurised yolk were determined at the temperatures of 5, 25, 45, and 65°C. Based on the geometry of the channels in the individual sections of the pasteurisation equipment, the character of the flow was estimated using the Re criterion and was found to be laminar in all parts of the system. The work includes the comparison of the average residence times obtained by (a) the method of volumes, (b) the analysis of the conductivity response, (c) the estimate made by using the TUPLEX software, and (d) the estimate of the peaks of the conductivity response. |
Optimisation of indirect competitive ELISAs of a-, b-, and k-caseins for the recognition of thermal and proteolytic treatment of milk and milk productsM. Vítková, P. Rauch, L. FukalCzech J. Food Sci., 2002, 20(2):53-62 | DOI: 10.17221/3510-CJFS Polyclonal antibodies were raised against six immunogens (three native and three thermally treated casein fractions: a+b-casein, k-casein and whole casein). Using these antibodies the procedures of an indirect competitive enzyme immunoassay (ELISA) were constructed, optimised and characterised for determination of each immunogen. It was found that ELISA of caseins is very specific without any interferences of whey proteins and with proportionally low cross-interactions between caseins. Detection limits for a-, b-, and k-caseins and whole casein were 110, 49, 58 and 505 ng/ml, respectively. The coefficient of variation was lower than 12% in intra-assay and lower than 9% in inter-assay. The developed ELISA format was used to study changes in casein immunoreactivity during heat-treatment and proteolytic hydrolysis. Heating below 100°C did not change the milk immunoreactivity but heating above 100°C caused its significant changes. Depending on type of proteolytic treatment (with enzyme preparation Pancreatin or with microbial cultures of Lactobacillus helveticus and Lactococcus) a decrease and an increase in casein immunoreactivity were observed. While Pancreatin reduced the casein immunoreactivity substantially (5-1000 times in dependence on the casein type), the more gentle proteolysis by bacteria caused not only its reduction (even 100 times at k-casein) but also its increase (1.5 times at a-casein). |
Estimation of the baking quality of wheat flours based on rheological parameters of the mixolab curveIuliana Banu, Georgeta Stoenescu, Violeta Ionescu, Iuliana AproduCzech J. Food Sci., 2011, 29(1):35-44 | DOI: 10.17221/40/2009-CJFS The Mixolab device in view of the characterisation of the thermo-mechanical behaviour of ten different flours, and establishing the correlations between the rheological parameters of wheat flour supplemented with different additives such as fungal α-amylase, fungal hemicellulase, and fungal xylanase weres exploted. The rheological measurements were performed using the Mixolab, Alveograph, and Rheofermentometer. Our results indicated significant positive and negative correlations between the parameters investigated. The changes of the Mixolab curve trend depended on the amylase doses. Significant correlations were established also between the Mixolab parameters and the results of the baking tests; the β slope, C2, C3, and C4 were positively correlated with the specific volume of the bread. Taking into account the results obtained, we may conclude that Mixolab is a complex device that renders the evolution of the bread during the entire technological process, from the dough making to the starch retrogradation. |
Microwave treatment and drying of germinated peaM. Skulinová, P. Kadlec, J. Kaasová, J. Dostálová, M. Zátopková, V. Hosnedl, J. HrachovinováCzech J. Food Sci., 2002, 20(1):23-30 | DOI: 10.17221/3505-CJFS It is possible to use germination of grain legumes as the most effective way of decreasing a high content of a-galactooligosaccharides which undesirably affect the nutritive value and acceptability of legumes. Content of a-galactooligosaccharides was reduced to 38% (Gotik cultivar) and to 45% (Grana cultivar) of the original value after 2 days of germination. The aim of further processing was to dry germinated pea to final moisture content 12-14%. Very interesting results were obtained when microwave heating was used as a preliminary treatment before hot air drying. Microwave treatment reduces the time of drying. The contents of soluble carbohydrates (sucrose, raffinose, stachyose and verbascose), proteins and trypsin inhibitor activity were determined as criteria of microwave heating effects on the chemical composition of germinated pea. Germinated pea was used for the preparation of pea soups and these pea dishes were sensory evaluated. |
Microwave heating - the influence of oven and load parameters on the power absorbed in the heated loadJ. Houšová, K. HokeCzech J. Food Sci., 2002, 20(3):117-124 | DOI: 10.17221/3521-CJFS The microwave power is a parameter greatly influencing the rate of heating. Several authors reported on certain differences between the rated power output as a parameter used by oven manufacturers in the labelling of ovens, and the power actually delivered to the heated product. A review of the respective information is given in this article together with the results of own experiments following the influence of the oven type and the heated substance parameters on the power actually absorbed in the substance volume during its heating. As the heated substance, water and solutions of NaCl and sucrose of different concentrations were used. For the heating, four types of domestic microwave ovens and glass and plastic containers, were used. The decreasing of the efficiency of heating with the decreasing volume of the heated substance and a certain relation between the rate of this decrease and the types of oven and of substance was estimated. With the small cavity ovens, a lower rate of the decrease of the absorbed microwave power with the decreasing volume of the substance was found as compared to the large cavity oven. A certain influence of other technical oven parameters is shown in the comparison of the tests results with the ovens of the same rated power and the cavity volume. In addition to the substance volume, also its dielectric properties probably influence the microwave power absorbed in small samples during the heating. No simple dependence can be seen on the basis of the tests results between the type of container used in the tests and the power absorbed in the heated substance. |
Influence of the amount of rennet, calcium chloride addition, temperature, and high-pressure treatment on the course of milk coagulationA. Landfeld, P. Novotná, M. HouškaCzech J. Food Sci., 2002, 20(6):237-244 | DOI: 10.17221/3537-CJFS Coagulated gel was characterised using an oscillation rheometer Rheostress RS 150. The influence was monitored of the additions of rennet and CaCl2, of temperature, and of high-pressure treatment on the properties of coagulated gel. Parameters of coagulation were assessed, i.e. elastic modulus G', the time of the start of coagulation t0, and the time constant of congealation τ. In monitoring the influence of increasing additions of rennet and CaCl2, and of temperature increase, it was found that the time of the start of coagulation t0 and the time constant of congealation t decreased. The limiting shear storage modulus G'max was practically constant at various amounts of CaCl2 and was moderately decreasing with increasing temperature and rennet addition. This effect was possibly caused by the fact that the limiting value is a regression parameter extrapolated to infinity. The real values of the modulus for a given time increased with increasing levels of calcium chloride added. Milk treated by the pressure of 600 MPa for 10 min formed, during coagulation, a more solid gel, the shear storage modulus being, almost by 100% higher as compared with untreated milk. Value of the time constant of congealation was practically halved. |
Land suitability evaluation of bilverdy research station for wheat, barley, alfalfa, maize and safflowerAli Asghar Jafarzadeh, Parisa Alamdari, Mohamed Reza Neyshabouri, Siamak SaediSoil & Water Res., 2008, 3(10):S81-S88 | DOI: 10.17221/15/2008-SWR In the present study and research work, land suitability evaluation (qualitative classification) was made for the Bilverdy research station of the Islamic Azad University in East Azarbaijan for wheat, barley, alfalfa, maize and safflower. The Simple Limitation Method (SLM), the Limitation Method regarding Number and Intensity (LMNI) and the Parametric Methods (PM) such as the square-root and the Storie methods were used. The landscape, climate and soil and characteristics that influence suitability of the land for particular crops have been combined according to the adopted methodology. Economic factors were excluded and moderate level of management was assumed. The results of different methods show that the most important limiting factors are climate, pH, organic matter (OM), gravel, salinity and sodicity, taken either alone or in combination. For safflower, the cation exchange capacity (CEC) can be added to these factors. Evaluation by the SLM and LMNI methods result in similar suitability classes, which confirms previous findings by other researchers for the same crops. However, in many cases the use of parametric methods, especially the square-root method, turned to be more realistic in distinguishing separate suitability classes. This study not only compares different methods and their results but also evaluates the suitability of the study area for particular crops. According to the square-root method, the area can be recommended as marginally suitable for cultivation of wheat, barley, alfalfa and safflower and is expected to yield about 40-65% of optimal production. |
Reincident corneal epithelial inclusion cyst in a dog: a case reportE.M. Martin-Suarez, A. Galan, J.M. MolledaVet Med - Czech, 2009, 54(2):84-88 | DOI: 10.17221/3003-VETMED An unilateral corneal epithelial inclusion cyst (CEIC) in a 8-years-old female mixed Poodle is reported. The cyst had been observed for 60 days, was unique, not congenital and only one eye was involved. One year prior to the referral the dog was treated with antibiotics due to an ocular trauma caused by a fight with a cat. In the same eye, palpebral melanocytic tumor and corneal dystrophy were also observed. In order to remove the CEIC a superficial keratectomy was performed. Collagen contact lens and topical antibiotics were the medical treatment of choice. Fifteen month after surgery the dog was referred for recurrence of the CEIC. A second keratectomy and similar topical treatment was attempted again. A second recurrence 16 months after surgery has not been observed to the date. Cytology and histology analysis of the cyst confirmed the diagnosis of the CEIC. Microbiologic studies were also realized and Staphylococcus epidermidis was aisled twice in fifteen months. In this case a relapsing CEIC is reported associated to S. epidermidis contamination. Corneal dystrophy and palpebral melanoma were concomitant lesions, although no relations with the CEIC were concluded. |
Rumen fermentation characteristics in pre-weaning calves receiving yeast culture supplementsB. Hučko, V.A. Bampidis, A. Kodeš, V. Christodoulou, Z. Mudřik, K. Poláková, V. PlachýCzech J. Anim. Sci., 2009, 54(10):435-442 | DOI: 10.17221/1674-CJAS In an experiment with 45 neonatal male Holstein calves, effects of yeast cultures Yea-Sacc® 1026 (SC) containing Saccharomyces cerevisiae (strain 1026) and Vitex (KF) containing Kluyveromyces fragilis (strain Jürgensen) on rumen fermentation characteristics were determined. From day 4 to day 56 of age, the calves were allocated to one of the three dietary treatments (Control, SC, and KF) of 15 animals each, placed in individual pens, and fed 4 l of whole milk twice daily and a basal concentrate mixture ad libitum as calf starter feeds. The control treatment was not supplemented with yeast culture. The yeast culture supplements Yea-Sacc® 1026 and Vitex were top-dressed at 10 g/calf daily on the basal concentrate mixture of treatments SC and KF, respectively. At the end of the experiment (day 56), all calves were slaughtered and the rumen fluid was analysed. The administration of yeast cultures Yea-Sacc®026 and Vitex to calves did not affect final body weight (BW), BW gain, dry matter intake, feed conversion ratio, ruminal pH, lactic acid concentration and the molar proportion of propionic acid, but it decreased (P < 0.05) the total volatile fatty acid concentration and the molar proportion of butyric acid, and increased (P < 0.05) the molar proportion of acetic acid and the acetate to propionate ratio. In addition, the microbial cellulolytic activity was higher in calves that received both yeast cultures compared to the control treatment. The results of this study suggest that the ruminal fermentation was more stable in calves receiving yeast culture supplements. |
Effects of putrescine and low temperature on the apoplastic antioxidant enzymes in the leaves of two wheat cultivarsT. Çakmak, Ö. AticiPlant Soil Environ., 2009, 55(8):320-326 | DOI: 10.17221/1037-PSE The effects of putrescine (a polyamine), low temperature and their combinations on the activities of apoplastic antioxidant enzymes were studied in the leaves of two wheat cultivars, winter (Dogu-88) and spring (Gerek-79). Fifteen-day-old wheat seedlings were treated with putrescine solutions (0.1, 1 and 10mM) prior to cold treatment (5/3°C). The activities of apoplastic catalase, peroxidase and superoxide dismutase were determined in the leaves both under normal and cold conditions at 1, 3 and 5 days. The results indicate that cold treatment significantly increased the activities of apoplastic catalase, peroxidase and superoxide dismutase in winter wheat while not generally affecting spring wheat. Under control conditions, the putrescine treatments were more effective in increasing the enzyme activities in winter wheat than in spring wheat. However, under cold conditions, the putrescine treatments surprisingly induced enzyme activities in spring wheat while generally reducing those in winter wheat leaves. The results show that putrescine may act as an agent inducing primary changes in the apoplastic antioxidant system of wheat leaves during reactive oxygen species-mediated damage caused by low temperature stress. |
Leaf growth under temperature and light controlJ. Repková, M. Brestič, K. OlšovskáPlant Soil Environ., 2009, 55(12):551-557 | DOI: 10.17221/93/2009-PSE Dynamics of crop growth and photosynthesis are two main processes that are of major importance for adaptation of plants to their environment. Two experiments were carried out during 2005 and 2006 with sun and shaded barley plants. The results showed that leaf area increased with leaf position on the main stem up to leaf position 5 for sun and leaf position 6 for shaded plants, and then declined towards flag leaves. Air temperature affected leaf appearance, mainly at the beginning of the growing season. A positive correlation between leaf expansion duration (LED) and accumulated temperature sum was measured for both variants, LED linearly increased with temperature sum. Leaf expansion rate (LER) showed a similar dependence on accumulated air temperatures in both light variants. A strong relation was found between soil temperature and LER for the first four leaves of the main stem of shaded plants in 2006. In shaded environment the higher LER was associated with lower accumulated irradiance sum when light restriction supported an increase of leaf elongation and final leaf length. |
Economic development in Slovak agricultureZ. Chrastinová, V. BurianováAgric. Econ. - Czech, 2009, 55(2):67-76 | DOI: 10.17221/580-AGRICECON The article discusses economic development of Slovak agriculture in the period after the accession of Slovakia to the EU and after adopting the CAP. It evaluates agriculture as a whole and its contribution to the national economy, as well as the economic performance of the individual legal forms of business and production sectors. The results achieved by agriculture in 2004-2007 suggest that the income within the sector (except of 2005) has improved also due to the inflow of the EU subsidies. On the other hand, despite the growing aid the production output is shrinking, wages stagnate and the employment is falling. This suggests that the CAP should be changed after 2013, especially as regards the ways of subsidy payments. Economics of the individual products are largely affected by input prices, realisation prices, as well as by the volume of direct subsidies, namely in the plant production - the subsidies for crops grown on arable land, and in animal production - the subsidies per 1 Big Cattle Unit. |
Sanitation of fresh green asparagus and green onions inoculated with SalmonellaMiguel A. Martínez-Téllez, Francisco J. Rodríguez-Leyva, Ilce E. Espinoza-Medina, Irasema Vargas-Arispuro, Alfonso A. Gardea, Gustavo A. González-Aguilar, J. Fernando Ayala-ZavalaCzech J. Food Sci., 2009, 27(6):454-462 | DOI: 10.17221/138/2008-CJFS The absence of good agricultural and manufacturing practices in the production and postharvest handling of fresh produce, such as green asparagus or green onions increase the contamination risk by biological hazards like Salmonella. The objective of this work was to investigate the efficacy of chlorine (200 and 250 ppm), hydrogen peroxide (1.5% and 2%), and lactic acid (1.5% and 2%) sanitisers during different exposure times (40, 60, and 90 s) on the reduction of Salmonella enterica subspecie enterica serovar Typhimurium in inoculated fresh green asparagus and green onions. Washing with clean water only reduced < 1 log10 CFU/g in both vegetables. The most effective sanitiser evaluated for fresh green asparagus and green onions disinfection appeared to be 2% lactic acid reducing Salmonella growth close to 3 log10 CFU/g. Hydrogen peroxide was the least effective agent for Salmonella Typhimurium reduction. No effect was observed of the exposure time of inoculated product to sanitiser up to 90 seconds. These results confirm that lactic acid could be used as an alternative for fresh green asparagus and green onions sanitation. |
Antioxidant Activity in Variously Prepared Elderberry Foods and SupplementsK. Cejpek, I. Maloušková, M. Konečný, J. VelíšekCzech J. Food Sci., 2009, 27(10):S45-S48 | DOI: 10.17221/951-CJFS Antioxidant capacity of foods and food supplements based on berries and flowers of medicinal plant elderberry (Sambucus nigra L.) was assessed. Reducing properties of the samples and extracts were evaluated using amperometric detection at working electrode potential -0.8 V after HPLC separation. Moreover, antiradical activity of selected samples was determined by the means of spectrophotometric DPPH radical scavenging method. Electrochemical activity (EA) of fresh juice pressed from elder fruits amounted to 0.71 g AAE/l with anthocyanins as minor contributors (10.2%). Catechins and phenolic acids were the major active groups. During production of elder berry spread, even more than 90% of the EA compounds found in raw elder berry material can be destroyed. Comparable activity may be found also in the products from elder flowers. Although elder blossom syrups possessed similar EA regardless of the technology used (0.033-0.054 g AAE/kg), their chromatographic patterns were often very different. For example, no flavonols were present in the syrups, if traditional preparation comprising 24-h maceration with citric acid was applied. Analyzing the chromatographic patterns, one can distinguish different base materials and technology, which can be used for the authenticity confirmation. Herbal infusions from elder flowers, which contain more flavonols than are in syrups, were 16-27 times richer in EA than drinks prepared from the syrups after recommended dilution. Only the syrup designed for preventing and treating upper-respiratory viral infections showed the EA (0.09 g AAE/kg) comparable to that of herbal infusion (0.13 g AAE/l). |
A new method of cleaning solid surfaces contaminated with oilsV. Řezníček, V. Dvořák, K. Kykalová, J. Severa, J. Mareček, J. FryčRes. Agr. Eng., 2009, 55(4):141-148 | DOI: 10.17221/4/2009-RAE The aim of the work was to find an alternative way of cleaning roads and other kinds of solid surfaces contaminated as a result of accidents. The method is designed to dissolve oil leaks coming from motor vehicles, but it is also suitable for removing other liquids with similar physical and chemical characteristics, for example plant and paraffinic oils. The principle of this method is to emulsify the contaminant with the reagent foam. The foam is applied on the contaminated surface and it reacts with the contaminant, given rise to an emulsion. The process is supported by the mechanical movement of brushes, which mix the foam with the contaminant. The movement increases the sorption capacity of the foam and its stability. After the surface decontamination, the residual emulsion is removed, together with the foam, with a combined wet suction cleaner equipped with an emulsion defoamer. The aggregate emulsion is disposed of in special establishments, especially in dangerous waste incinerators. |
Determination of indigestible neutral detergent fibre contents of grasses and its prediction from chemical compositionF. Jančík, P. Homolka, B. Čermák, F. LádCzech J. Anim. Sci., 2008, 53(3):128-135 | DOI: 10.17221/2716-CJAS Five grass species (Dactylis glomerata L., Phleum pratense L., Lolium perenne L., Festuca arundinacea L.) and the hybrid Felina (Lolium multiflorum L. × Festuca arundinacea L.), commonly used in roughages for ruminants, were harvested at different maturities of primary growth (n = 60) and evaluated for contents of dry matter (DM), crude protein (CP), ash, crude fat, neutral detergent fibre (NDF), acid detergent fibre (ADF), acid detergent lignin (ADL), indigestible neutral detergent fibre (INDF) and digestible neutral detergent fibre (DNDF). INDF and DNDF contents were determined by in sacco rumen degradation of grasses for 12 days in non-lactating cows. ADL content was found to be highly correlated (P < 0.05) with DNDF (r = -0.87) and presented a reliable (R2 = 0.78; residual mean square error of 17.65 g/kg DM; P < 0.0001) parameter to predict INDF contents. Over a six-week period of maturation INDF contents increased (P < 0.0001) in all studied grasses. It was confirmed by this study that the INDF contents of grasses, which markedly increased during maturation, could be effectively predicted from ADL contents. |
Effects in genetic evaluation for semen traits in Czech Large White and Czech Landrace boarsJ. Wolf, J. SmitalCzech J. Anim. Sci., 2009, 54(8):349-358 | DOI: 10.17221/1658-CJAS Data on 75 567 ejaculates from 1 417 boars of the breeds Czech Large White and Czech Landrace collected in 23 AI centres between 2000 and 2007 were analyzed. Fixed effects were estimated from a four-trait animal model for semen volume, sperm concentration, motility and percentage of abnormal spermatozoa and from single-trait animal models for the total number of spermatozoa and the number of functional spermatozoa. Both the total number of spermatozoa and the number of functional spermatozoa were highest in winter and lowest in summer. Boar's age had a strong influence on semen volume, the total number and the functional number of spermatozoa; these traits increased especially in the first phase. The percentage of abnormal spermatozoa also increased with age. An interval between successive collections of 7 to 10 days yielded the best values for all semen traits. As semen traits are of direct economic importance for AI centres, it can be expected that the estimation of breeding value for semen traits will become important and that AI centres will choose among top boars for production and female reproduction traits the boars with better semen production. |
Complementary currency systems as a source of endogenous development of localitiesL. ZagataAgric. Econ. - Czech, 2004, 50(10):477-484 | DOI: 10.17221/5236-AGRICECON The paper tackles the issue of regional and social development. From a sociological point of view, it focuses on the phenomenon of complementary currency systems. The analysis shows that money, as a social institution, has got certain features, which have an impact on economic behavior of people. Establishing a currency on the local level, which would circulate as a complement of the national currency, brings certain social benefits to local society. Nowadays, there are many complementary currency systems all over the world, including Europe. The paper attempts to answer the question, how they can contribute to the local development. |
Effect of perforated foil and polypropylene fibre covers on growth of early potato cultivarsW. Wadas, E. Kosterna, A. KurowskaPlant Soil Environ., 2009, 55(1):33-41 | DOI: 10.17221/379-PSE This paper presents the results of a three-year research on the effect of perforated polyethylene foil and polypropylene fibre covers on the growth of early potato cultivars at various lengths of plant covering period (2 and 3 weeks after plant emergence). Plants grown under covers were higher, produced higher mass of above-ground parts, and were characterised by a smaller value of leaf weight ratio (LWR) and leaf area ratio (LAR) compared with the cultivation without covering. In the case of plant covering for 2 weeks after emergence the mass of leaves at the time of cover removal was on average almost 2 times higher and the mass of stems over 2.5 times higher than in the cultivation without covering; the values of LWR and LAR were however smaller by 0.094 and 0.137 m |
Mitigation of salt stress in strawberry by foliar K, Ca and Mg nutrient supplyE. Yildirim, H. Karlidag, M. TuranPlant Soil Environ., 2009, 55(5):213-221 | DOI: 10.17221/383-PSE Plant root and shoot dry weight, leaf relative water content (LRWC) and chlorophyll content were reduced by 30%, 21%, 15%, 34%, respectively, at 40mM NaCl as compared to non-salt stress conditions. However, membrane permeability (MP) of plant increased (85.0%) with increasing salinity. Foliar nutrient application (FNA) alleviated deleterious effects of salinity stress on growth and this effect was statistically significant. The highest alleviation effect of FNA at 40mM salinity stress was observed in the case of 10mM foliar KNO3 and Ca(NO3)2 application, resulting in increase in plant root dry weight (50%), shoot dry weight (50%), LRWC (8.2%) and MP decrease (27.4%) at 40mM NaCl. Phosphorus, Fe and Zn contents in shoots and roots of plants also increased with FNA treatments, but they were still much lower than those of non-salt stress treatment. Sulphur, P, Fe and Zn contents of shoots reached similar values as in non-salt stress treatment when KNO3 was applied, whereas Fe, Mn, Zn, and Cu contents of roots reached the values of non-salt stress treatment when Ca(NO3)2 was applied. |
Possible phosphorus losses from the top layer of agricultural soils by rainfall simulations in relation to multi-nutrient soil testsJ. MatulaPlant Soil Environ., 2009, 55(12):511-518 | DOI: 10.17221/80/2009-PSE The objective of the study was to examine a possibility of predicting phosphorus leaching from the top layer of agricultural soils by rainfall simulations by means of three multi-nutrient soil tests: Mehlich 3, NH4-acetate extraction and water extraction (1:5, w/v). Another objective was to determine parameters of maximum phosphorus losses after an extreme load of rainfall on the top layer. Forty soils from different localities of the Czech Republic were used for the experiment. A leaching experiment was conducted in pedological cylinders with a soil layer of about 1 cm and with the bottom from a glass microfibre filter with pores 1.2 μm in size. Within 15 days the soils were flooded ten times with 25 mm of simulated rainfall in a minimum interval of 1 day. The closest regression between the soil test and phosphorus leaching was computed for NH4-acetate soil test (R2 = 0.8831) and Mehlich 3 test (R2 = 0.8572) after the first application of 25 mm of rainfall. In water extraction it was for the mean of 10 simulated rainfalls (R2 = 0.8674). As leaching proceeded, the closeness of regression diminished due to fluctuations of P concentration in leachates (increases and decreases), mainly in soils with higher P-test. The increase in P concentration could be caused by the activation of phosphorus from Fe-phosphates under anaerobic conditions in wet soils. The steepest decrease in P concentration in leachates was observed in light soils with low CEC value and higher initial P-test. |
Determination of Fox grape genotypes (Vitis labrusca L.) grown in Northeastern AnatoliaH. Celik, B. Kose, R. CangiHort. Sci. (Prague), 2008, 35(4):162-170 | DOI: 10.17221/655-HORTSCI Northeastern part of Anatolia is a gene center of grapevine and a wide diversity of Fox grapes grow here. Viticulture and some grapevines in the Black Sea Region (in the north of Turkey) are on the verge of extinction; several types and varieties grown in this region have never been described and did not survive till present. For the past 10 years vineyards and grapevines in the Black Sea Region have been studied. In the present study, eighteen grapevines of foxy taste grown in the Artvin and Rize provinces were described. An ampelographic description of young shoot, mature shoot, young leaf, mature leaf, berry, bunch and seed were carried out using the OIV (Office International de la Vigne et du Vin) list for grapevine cultivars and Vitis species. However, several other parameters of the cultivars were measured for evaluation. |
Energy and the European UnionV. Jeníček, V. KreplAgric. Econ. - Czech, 2009, 55(1):1-11 | DOI: 10.17221/2501-AGRICECON There exists no energy policy in the European Union, but rather a whole series of long-term goals setting its strategic orientation. Until 2000, when the Green Book named "Towards the European Strategy of Energy Supplies Securing" was accepted, no real debate on the strategy of energy was held in the EU. The Green Book represents a key document of the European energy policy and it originated as a consequence of the fears of the European Committee regarding the growing energy dependence on the energy resources imports, from the politically not stable parts of the world. Among the three key points of the energy strategy, there belong stable supply of energy, acceptable energy prices and environment protection. With regard to the deepening European integration and interconnection of the individual member states economies, the decisions of one country also have an energy impact on the other states. Therefore, the cooperation among the individual members is necessary. |
Combination of linear and weighted goal programming with penalty function in optimisation of a daily dairy cow rationJ. Žgajnar, L. Juvančič, S. KavčičAgric. Econ. - Czech, 2009, 55(10):492-500 | DOI: 10.17221/2601-AGRICECON The aim of the paper is to present a developed spreadsheet tool for the formulation of a daily dairy cow ration. It is constructed on the basis of two linked sub-models developed on the MS Excel platform. It merges the common linear programming model and the weighted-goal programming model with a penalty function. The first sub-model is included in the tool to make an estimate of the least-cost magnitude that might be expected. The obtained result is entered into the second sub-model as the goal that should be met as closely as possible. The tool was tested at two different values of preferential weights for dairy cows with a 25 kg daily milk yield. The results obtained confirm the benefits of the applied approach. In contrast to the common linear program tools, which terminate at formulation of the least-cost ration, our tool provides more efficient rations (in both economic and nutritive terms) by fine-tuning the nutritive goals and by allowing for harmless deviations from these goals by application of penalty functions. |
Dissolved organic carbon concentrations under conditions of different forestcompositionM. Remeš, J. KulhavýJ. For. Sci., 2009, 55(5):201-207 | DOI: 10.17221/16/2009-JFS The study deals with the monitoring of dissolved organic carbon (DOC) concentrations in seepage water sampled from differently managed forest plots in the Drahanská vrchovina Upland. Simultaneously, the input of DOC in precipitation and throughfall is evaluated. Preliminary results show higher mobility level of carbon substances in forest soil in a pure spruce stand compared to mixed stand or a pure beech stand. DOC can be one of suitable characteristics to evaluate the conversion effectiveness of spruce monocultures. |
Quantity and distribution of fine root biomass in the intermediate stage of beech virgin forest Badínsky pralesP. Jaloviar, L. Bakošová, S. Kucbel, J. VencurikJ. For. Sci., 2009, 55(11):502-510 | DOI: 10.17221/31/2009-JFS The fine root biomass represents 3,372 kg/ha in the intermediate stage of the beech virgin forest with different admixture of goat willow, where the vast majority of this biomass is located in the uppermost mineral soil layer 0-10 cm. The variability of the fine root biomass calculated from 35 sample points represents approximately 90% of the mean value and reaches the highest value within the humus layer. The total fine root length investigated in 10 cm thick soil layers decreases with increasing soil depth. A significant linear relationship between the fine root length (calculated per 1 cm thick soil layer and 1 m2 of stand area) and the soil depth was confirmed, although the correlation is rather weak. The number of root tips decreases with increasing soil depth faster than the root length. As the number of tips per 1 cm of root length remains in the finest diameter class without significant changes, the reason is above all a decreased proportion of the finest root class (diameter up to 0.5 mm) from the total fine root length within the particular soil layer. |
The Effect of Fertilisation Method on Selected Elements Content in Tomatoes (Lycopersicon lycopersicum)I. Poustková, L. Kouřimská, K. Václavíková, D. Miholová, L. BabičkaCzech J. Food Sci., 2009, 27(10):S394-S396 | DOI: 10.17221/599-CJFS Fermented pig slurry was used for two kinds of tomatoes fertilisation as a replacement of industrial mineral fertilisers in three-year experiment and selected elements (Pb, Cd, As, Zn and Hg) content were monitored by the AAS method. The results obtained showed that anaerobically fermented pig slurry can be a suitable alternative to mineral fertiliser use. Its use as an organic fertiliser also did not decrease the hygienic quality and safety of the grown vegetable products, and all tomato samples fulfilled the heavy metals legislation limits for Pb, Cd, As, Zn and Hg content. Statistically significant (P < 0.05) influences of the year, cultivar and fertilisation method were found in case of zinc content. No statistically significant differences in case of arsenic were discovered. Statistically significant influence (P < 0.05) of the year was found in case of cadmium and mercury contents. |
