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Results 2731 to 2760 of 5824:

Susceptibility of bacteria of the Enterococcus genus isolated on Lithuanian poultry farms

M. Ruzauskas, R. Siugzdiniene, V. Spakauskas, J. Povilonis, V. Seputiene, E. Suziedeliene, R. Daugelavicius, A. Pavilonis

Vet 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.

Changes in methane release from organic matter passing through the digestive tract of horses

L. Kolář, M. Maršálek, J. Frelich, S. Kužel, P. Smetana, J. Zedníková, M. Švecová

Czech J. Anim. Sci., 2009, 54(3):112-120 | DOI: 10.17221/1677-CJAS

Using the tests of methanogenic activity (TMA) changes in methane yield (YCH4) and anaerobic degradability (Dc) of organic matter of feeds and excrements were studied in an experimental group of six horses while complete analytical methods were applied (N-compound matters, proteins, non-protein N-compound matters, fat, nitrogen-free extract, ash, crude fibre, organic matter, NDF, ADF, hemicelluloses, cellulose, lignin and chemical oxygen demand COD) and the material balance was determined. The horses utilised 48.8% of organic matter of feeds in dry matter while the daily weight of droppings was 21 kg with 5.20% of dry matter and 4 kg of urine with 7% of organic matters. It is important that the theoretical methane yield per 24 hours corresponding to the organic matter of ingested feeds which was transferred to excrements is 1.771 m3 CH4 at 0°C and 1 013.25 hPa while the actual daily methane yield of droppings is 1.739 m3 CH4 at 0°C and 1 013.25 hPa, i.e. practically identical, because the yield from urine organic matters was not included in the actual daily methane yield. Because the anaerobic degradability of the used feed mixture and horse droppings is practically identical, it is obvious that besides the enteric fermentation according to the reaction CO2 + 4 H2 → CH4 + 2 H2O by hydrogenotrophic methanogens no classical anaerobic digestion takes place in the digestive tract of horses; it means that the horse breeding sector is not a factor contaminating the atmosphere by methane.

Production and quality of milk thistle (Silybum marianum[L.] Gaertn.) cultivated in cultural conditions of warm agri-climatic macroregion

M. Habán, P. Otepka, Ľ. Kobida, M. Habánová

Hort. Sci. (Prague), 2009, 36(2):69-74 | DOI: 10.17221/38/2008-HORTSCI

A polyfactorial field experiment was established and investigated during vegetation periods from 2004 to 2007 at the Dolná Malanta locality (Nitra district, Slovakia). The following parameters were measured: (1) yields of milk thistle (Silybum marianum [L.] Gaertn.) achenes, i.e. fruits, in 2004-2007; (2) content of silymarin in dry fruits of milk thistle in 2006-2007; and (3) total yields of silymarin per ha in 2006-2007. Factors of the experiment were as follows: (1) crop residues of cultivated pre-crop (no crop residues - K, with crop residues - R); (2) cultivation of freezing-out intercrop (no intercrop - B, with intercrop - M); (3) fertilization using artificial fertilizers (no fertilization - O, with fertilization - F); (4) year of cultivation (2004-2007). The highest yields of milk thistle fruits were recorded in 2006: from 1,426.5 kg/ha (RBO variant - incorporated crop residues without intercrop, no artificial fertilizers) to 1,832.0 kg/ha (KBF variant - without crop residues, without intercrop and with application of artificial fertilizers). The highest content of silymarin complex in dry fruits of milk thistle was measured in 2007: from 15.14 mg/kg (RMF - with crop residues, intercrop and fertilization) to 20.01 mg/kg (KBO - without crop residues, intercrop and fertilization). The highest total yield of silymarin per ha was recorded in investigated variants in 2006; in variant without crop residues it ranged from 16.45 kg/ha (KMF - with intercrop, with fertilizers) to 24.62 kg/ha (KMO - with intercrop, no fertilization).

Spatial distribution of soil nutrients after the establishment of sand-fixing shrubs on sand dune

X.W. Dong, X.K. Zhang, X.L. Bao, J.K. Wang

Plant Soil Environ., 2009, 55(7):288-294 | DOI: 10.17221/13/2009-PSE

Caragana microphylla Lam., an indigenous leguminous shrub, was the dominant plant species to be used to control desertification in semi-arid Horqin Sandy Land. To elucidate the cover effect of Caragana microphylla planted for 25 years on spatial distribution of soil nutrients including C, N, P and K, soil samples were taken from four soil depths (0-5 cm, 5-10 cm, 10-20 cm, and 20-40 cm) and three slope positions (windward slope, top slope, and leeward slope). Soil nutrients under shrubs (US) and between shrubs (BS) were compared to investigate the enrichment effect of plantation. The results showed that soil nutrients except total K were significantly higher in surface soil (0-5 cm) than in deeper layer soil (P < 0.01). Significant differences were found in the contents of total organic carbon, total nitrogen, total phosphorus, and total K at different slopes. The contents of total organic carbon and total nitrogen were higher in US than in BS (P < 0.05), but pH was lower (P < 0.01). Our results indicated that the establishment of Caragana microphylla increased the accumulation of soil nutrients, and played an important role in restoring sand dune ecosystems.

Engineering rice based medium for production of lovastatin with Monascus species

Bibhu Prasad Panda, Saleem Javed, Mohamed Ali

Czech J. Food Sci., 2009, 27(5):352-360 | DOI: 10.17221/47/2008-CJFS

Angkak (red mold rice, red yeast rice, Chinese red rice), a traditional Chinese functional food is produced by solid-state fermentation of cooked non-glutinous rice with Monascus species. The secondary metabolite of Monascus species, monacolin K (lovastatin), has been proved to lower blood lipid levels. In this study, the best Monascus purpureus strain was selected from MTCC 369, 410, 1090 based on lovastatin concentration. Four medium parameters (NH4Cl, MgSO4, NaCl, CaCl2) screened by Plackett-Burman design from total nine medium variables were optimised by Box-Behnken design of response surface methodology. Maximum lovastatin production of 3.420 mg/g was predicted in the solid medium containing 20 g rice and 40 ml liquid nutrient (NH4Cl 14.32 g/l, MgSO4 0.76 g/l, NaCl 14.65 g/l, and CaCl2 0.54 g/l) by the point prediction tool of Design Expert Ver. 7.1 software at 14th day of fermentation.

Oxygen Transfer coupled to Oxidation Reactions: Numerical Tool for Optimizing Nutritional Quality of Food

C. Pénicaud, V. Guillard, S. Peyron, N. Gontard

Czech J. Food Sci., 2009, 27(10):S28 | DOI: 10.17221/952-CJFS

Dissolved oxygen, due to atmospheric oxygen transfer through food, lowers the overall nutritional, chemical, and physical qualities of food during storage and marketing, causing food product less acceptable or unacceptable to consumers. Oxygen can react with all food components: lipids, proteins, sugars, and vitamins. To imagine new strategies of protection of food, it is necessary to evaluate oxygen transfer and to couple this transfer to chemical reactions. In this work, ascorbic acid oxidation under aerobic conditions has been studied. The objective is to model ascorbic acid degradation regarding both ascorbic acid and oxygen influence, the last one depending on diffusion rate into food and oxygen consumption during reaction. Ascorbic acid degradation was first studied in water under stirring in which oxygen diffusion could be neglected. Experiments were carried out during six days, under six different oxygen contents varying between 0 (simulating packaging in anaerobic conditions) and 21% (simulating packaging in atmospheric conditions) at 8, 14, 20, 27 and 33°C. Thanks to these experiments, kinetic parameters as reaction orders for ascorbic acid and oxygen, kinetics constant and activation energy have been identified. Oxygen sorption kinetics were measured thanks to luminescence oxygen sensors, placed into of a thin layer of agar gels 1% (w/w) exposed to eight successive increasing oxygen content in the atmosphere (from 0% to 21%). The probes measured oxygen content into material as a function of time. Oxygen diffusivity in agar gel was then identified by minimising the sum of square error between experimental results and those predicted by a mathematical model. Finally, using mass balance equation on oxygen and ascorbic acid contents, oxidation reaction and oxygen diffusion in model food systems were modelled. Validation of the model was carried out on agar gels 1% (w/w) enriched in ascorbic acid (1000 mg/l) in which the ascorbic acid content profile was determined by slicing each cylindrical gels in thin layers of 0.5 mm thick and by determining the ascorbic acid content in each layer. Knowing initial ascorbic acid content, oxygen content in atmosphere and temperature, the model can predict evolution of ascorbic acid content in the product as a function of time. This model could be used as a tool to imagine new strategies for protection of interest compounds in food.

Meteorological situations in 2007 and their implications for the cycling of selected chemical elements in a Central Bohemian forested catchmentOriginal Paper

Petra Kubínová, Petr Drahota, Jaroslav Fišák, Petr Skřivan, Jan Rohovec

Soil & Water Res., 2009, 4(4):149-158 | DOI: 10.17221/38/2008-SWR

Comparison of the annual bulk precipitation in the Lesní potok experimental catchment (Central Bohemia, Czech Republic) in the hydrological year 2007 (758.8 mm) with the average annual value between the years 1995 and 2006 (737.4 mm) indicates almost similar values, whereas the stream water discharge in 2007 amounts to only 38.2% of the average annual value of the comparable time span. It has been found that the low discharge in 2007 resulted from the extremely temperate winter and from the anomalous distribution of the precipitation events throughout the year. These factors, together with higher pH values of stream water in 2007, reduced the output of elements from the catchment. The output of dissolved Al, Be, Cd, Mn, Ni, Pb, and Zn through the stream water in 2007 is amounted to only 15 to 20% of their annual output in 1995-2006. The unusually low output of the elements distinctly affected their budgets in the catchment changing towards more positive mass balance values. This holds especially for the major base cations Ca, Mg, and Na (e.g. shift from -1460 to -127 mg/m2year for Ca and from -572 to +15 mg/m2year for Mg) and also for the trace elements Be, Mn, Ni, and Sr (e.g. shift from -368 to +144 μg/m2year for Be, from 2820 to 14 300 μg per m2year for Mn, and from 191 to 7 790 μg/m2year for Sr). The meteorological conditions in 2007 induced, to a certain extent, the recovery of the acid-sensitive ecosystem disturbed by a long-term high input of acid precipitation.

EST-SNPs in bread wheat: discovery, validation, genotyping and haplotype structureOriginal Paper

Sachin Rustgi, Rajib Bandopadhyay, Harindra S. Balyan, Pushpendra K. Gupta

Czech J. Genet. Plant Breed., 2009, 45(3):106-116 | DOI: 10.17221/16/2009-CJGPB

The present study involves discovery, validation and use of single-nucleotide polymorphisms (SNPs) in bread wheat utilizing 48 EST-contigs (individual contigs having 20-89 ESTs, derived from 2 to 11 different genotypes). In order to avoid a problem due to homoeologous relationships, the ESTs in each contig were classified into 175 sub-contigs (3.7 sub-contigs/EST-contig) using characteristic homoeologue sequence variants (HSVs), which had a density of 1 HSV every 136.7 bp. In silico analysis of sub-contigs led to the discovery of 230 candidate EST-SNPs with a density of 1SNP/273.9 bp. Locus specific primers (each primer pair flanking 1-18 SNPs) were designed utilizing one sub-contig each from 42 EST-contigs that contained SNPs, the remaining 6 contigs having no SNPs. To provide locus specificity to the PCR products, each primer was tagged with an HSV at its 3' end. Only 10 primer pairs, which gave each a characteristic solitary band, were utilized to validate EST-SNPs over 30 diverse bread wheat genotypes; 7 SNPs were validated through resequencing the PCR products. Allele specific primers were designed and utilized for genotyping of 50 diverse bread wheat accessions (including 30 bread wheat genotypes previously used for validation of SNPs), with an aim to test their utility in genotyping and map construction. The allele specific primers allowed the classification of 50 genotypes in two alternative allele groups for each SNP as expected, thus suggesting their utility for genotyping. Of the above 7 validated SNPs, 4 belonged to a solitary locus (PKS37); 7 haplotypes were available at this locus. Altogether, the results suggested that EST-SNPs constitute an important source of molecular markers for studies on wheat genomics.

Climate change and its possible influence on the occurrence and importance of insect pests

Zdeněk Laštůvka

Plant 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.).

Hydroperoxide Formation of Steryl Ester

M. Lehtonen, S. Kemmo, A.-M .Lampi, V. Piironen

Czech J. Food Sci., 2009, 27(10):S224 | DOI: 10.17221/936-CJFS

Phytosterols and -stanols are added to food products because of their known ability to lower serum cholesterol levels. They are applied either in their free or esterified forms, i.e. as fatty acid esters. Sterols are known to form variety of oxidation products under exposure to heat, light and metal contaminants, for example in food processing conditions. Since these oxides may have adverse health effects, the oxidation process needs to be studied. Until recently, sterol oxidation studies have concentrated on following the formation of secondary oxidation products in free sterol and steryl esters, but little is known about the oxidation of steryl esters as intact molecules. The aim of this experiment was to study primary autoxidation of intact steryl ester by measuring hydroperoxide formation in bulk cholesteryl ester. Cholesteryl linoleate was maintained at 60°C for 0-72 h after which formed hydroperoxides were determined with normal phase high performance liquid chromatography connected to diode array detector (HPLC-DAD). Also peroxide value (PV) was measured to indicate the total amount of formed hydroperoxides. With HPLC method steryl ester -OOH's could be analysed as intact esters, without saponification. A gradient elution was performed with 0.3-10% methyl-tert-butyl ether (MTBE) in heptane followed by cleanup with 30% MTBE. Compounds were detected with DAD at wavelengths 206 nm and 234 nm. Peroxide value indicated that the formation of hydroperoxides reached the maximum after 12 h of prolonged heating. According to HPLC data, at this time point less than 10% of the hydroperoxide groups were located in the sterol moiety and more than 90% in the fatty acid chain. The proportion of sterol-OOH's increased as the heating continued; at 24 h 20% and at 48 h 30%. However, after 72 h no hydroperoxides were observed. In conclusion, oxidation of cholesteryl linoleate started in the fatty acid moiety and as the reaction progressed more of the sterol -OOH's were observed, though at all time points fatty acid -OOH's were dominating.

The effect of kaolin feeding on efficiency, health status and course of diarrhoeal infections caused by enterotoxigenic Escherichia coli strains in weaned piglets

M. Trckova, H. Vondruskova, Z. Zraly, P. Alexa, J. Hamrik, V. Kummer, J. Maskova, V. Mrlik, K. Krizova, I. Slana, L. Leva, I. Pavlik

Vet 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.

Effect of microbial phytase and diet fermentation on ileal and total tract digestibility of nutrients and energy in growing pigs

S. Nitrayová, P. Patráš, M. Brestenský, J. Zelenka, J. Brož, J. Heger

Czech J. Anim. Sci., 2009, 54(4):163-174 | DOI: 10.17221/1743-CJAS

A digestibility experiment using six ileally cannulated growing gilts (initial BW 31.6 kg) was carried out to study the effect of microbial phytase and diet form on apparent ileal and total tract digestibilities of dry matter (DM), nitrogen (N), phosphorus (P), calcium (Ca) and energy and on apparent ileal digestibility of amino acids. The basal P-deficient diet was fed either dry or mixed with water (feed:water ratio 1:2.5) and fermented in a laboratory setup. The enzyme was added to the dry diet at four levels (0, 1 000, 1 500 and 3 000 U/kg) and to the liquid fermented diet at two levels (0 and 1 000 U/kg) using a 6 × 6 Latin square design. The supplementation of microbial phytase to the basal diets significantly (P < 0.05) improved ileal and total tract digestibility of P and tended to improve the digestibility of Ca. Phytase supplementation at 3 000 U/kg to the dry diet improved ileal and total tract P digestibility by approximately 30 and 60%, respectively. A similar effect was found in the liquid fermented diet supplemented with phytase at 1 000 U/kg. As a result of improved P digestibility, faecal P excretion was reduced by 20-40%. There was no significant effect of phytase addition or diet fermentation on the digestibility of DM, N, energy or amino acids. The response in amino acid digestibility to phytase calculated with acid insoluble ash as a marker was slightly higher than that calculated with Cr2O3.

Influence of Cheese Type and Maturation Time on the Early Maillard Reaction in Cheese

U. Schwietzke, U. Schwarzenbolz, T. Henle

Czech J. Food Sci., 2009, 27(10):S140-S142 | DOI: 10.17221/1111-CJFS

Formation and degradation of Amadori products (APs) originating from the early Maillard reaction during maturation of three different commercial cheeses, namely Cheddar, Emmentaler and Gouda, was investigated. APs were analysed as the corresponding N-(furoylmethyl) amino acids formed after acid hydrolysis. The contents of furosine, which is a hallmark for Amadori products resulting from derivatisation of lysine at the ε-amino group (ε-APs), ranged from 4 to 20 mg/100 g protein, corresponding to 33 to 159 μmol of lysine Amadori product per 100 g protein in the cheese samples at the start of the ripening period. Furosine contents declined during ripening in all investigated cheeses, in which cheese type and the stage of ripening influenced the rate of furosine decline. In contrast to this, all detectable N-terminal APs (α-AP) decreased at similar rates. The mean total content of these substances ranged from 12 to 48 μmol/100 g protein. The ratio between ε-APs and α-APs can be used as an indicator for the cheese ripening.

Time-Intensity Studies of Sweeteners

K. Čmejlová, Z. Panovská, A. Váchová, D. Lukešová

Czech J. Food Sci., 2009, 27(10):S327-S329 | DOI: 10.17221/916-CJFS

We used time-intensity studies in this work for evaluating the perception of sweet taste of sucralose, aspartame, and saccharose over time. In second part of this study the mixture of sweeteners and zinc sulphate, which modifies sweet taste perception, was used. We determined the following parameters from the assessor's charts of time profile: maximum intensity of sweet taste and the time which was needed to get to its maximum, the time period of perception of sweet taste and the area under the curve. For evaluation each assessor received 20 ml of a water solution with the sweetener followed by the mixture of the same sweetener with zinc sulphate. The intensity of sweet taste was measured before and after spitting out the solution. Then it was measured at intervals of 5 s for 70 seconds. It can be seen from the charts that sucralose has a more gentle sweet taste perception in time than the other sweeteners and that the zinc sulphate modifies the sweet taste but it does not inhibit it absolutely.

The effects of partial replacement of corn silage on biochemical blood parameters in lactating primiparous dairy cows

U. Polat, H. Gencoglu, I.I. Turkmen

Vet Med - Czech, 2009, 54(9):407-411 | DOI: 10.17221/72/2009-VETMED

The aim of this experiment was to investigate the effects of partial replacement of corn silage with long alfalfa hay and/or coarse chopped wheat straw on biochemical parameters in late lactating Holstein primiparous dairy cows. Twelve late lactating Holstein primiparous cows including four cows equipped with a rumen cannula, averaging 210 ± 20 days in milk and weighing 575 ± 50 kg were randomly assigned in a 4 × 4 Latin square design. During each of four 21-days periods, cows were fed four total mixed diets that were varied in the forage sources: (1) 50% corn silage (CS), (2) 35% corn silage + 15% wheat straw (CSW), (3) 35% corn silage + 15% alfalfa hay (CSA), (4) 25% corn silage + 10% wheat straw + 15% alfalfa hay (CSWA). At the end of the feeding period, blood samples were taken from jugular vein. Serum glucose, total protein, albumin/globulin, creatinine, creatinin kinase, urea and uric acid levels were determined by using Auto Technicon DAX 72 autoanalyzer. While serum glucose, albumin, globulin, urea, uric acid and creatinine kinase activity were not found significantly different among groups, serum total protein (between CS and CSA, CS and CSWA) and creatinine (between CSA and CSWA) levels had statistical significance at the levels of P < 0.05. It is concluded that rumen propionate and ammonia levels may be good indicator for glucose and BUN, respectively.

Effect of land use on soil enzyme activities at karst area in Nanchuan, Chongqing, Southwest ChinaOriginal Paper

Q. Li, J.H. Liang, Y.Y. He, Q.J. Hu, S. Yu

Plant Soil Environ., 2014, 60(1):15-20 | DOI: 10.17221/599/2013-PSE

The study of soil enzyme activities under different land use is of importance for exploration of the soil quality evolution and its evaluation during the revegetation at karst area in Nanchuan, Chongqing, China. Seven kinds of land use were chosen as subject, aiming at revealing the changes in soil enzyme activities through experimental and statistical analysis. The results showed that different land use significantly influenced the enzyme activities. Soil urease, invertase, catalase and amylase behaved the different change. A descending order of urease activity was artificial forest, natural forest, shrubbery, grassland, slope field into terrace, rock desertification and farmland. As to invertase and amylase, they have no clear change orderliness with land use change. Moreover, no significant change was observed in catalase activity and the lower value was found in natural forest. The above results cannot reflect the land use effect on the enzyme activities. According to the soil enzyme index (SEI), it can be seen that the SEI changed with an order of natural forest > artificial forest > grassland > shrubbery > farmland > slope field into terrace > rock desertification, which can objectively and fully evaluate the land use change in soil enzyme.

Quantification of nutrient content in the aboveground biomass of teak plantation in a tropical dry deciduous forest of Udaipur, India

J. I. Nirmal Kumar, R. N. Kumar, R. Kumar Bhoi, P. R. Sajish

J. For. Sci., 2009, 55(6):251-256 | DOI: 10.17221/107/2008-JFS

This study was designed to evaluate the quantification of the nutrient content of aboveground biomass of teak plantation in a tropical dry deciduous forest of Udaipur, Rajasthan, India. The nutrient contents in the total biomass of teak in the plantation were 165.47 kg/ha N, 20.96 kg/ha P, 35.06 kg/ha K, 49.29 kg/ha Ca, 31.52 kg/ha Mg, 4.27 kg/ha Na, 4.06 kg/ha S and 3.21 kg/ha Cl. In total, 42.93% of the dry matter accounted for crown biomass (leaves, branches, twigs and reproductive parts), which in turn accounts for 60.93% N, 58.63% P, 54.30% K, 51.40% Ca, 62.5% Mg, 53.62% Na, 59.85% S and 60.74% Cl of the aboveground biomass, whereas 57.07% of the dry matter account for trunk biomass (bole bark and bole wood), which in turn accounts for 39.07% N, 41.37% P, 45.70% K, 48.6% Ca, 37.5% Mg, 46.38% Na, 40.15% S and 39.26% Cl.

Enterococcus faecium growth model

Pavel Čermák, Aleš Landfeld, Pavel Měřička, Milan Houška

Czech J. Food Sci., 2009, 27(5):361-371 | DOI: 10.17221/79/2008-CJFS

Enterococci are bacteria commonly found in humans. However, these bacteria can cause severe infections in susceptible individuals. The strains of Enterococcus faecium have demonstrated an increasing resistance to antibiotics, which is considered an important virulence factor. The contribution of E. faecium to the infection-related illnesses has recently increased, which involves most of the isolated Vancomycin-Resistant Enterococcus (VRE) strains. Enterococci are common contaminants of human milk processed in milk banks, and the consumption of contaminated milk can cause severe infection-related complications if the control mechanisms fail to detect the contamination. Extensive data are available on the growth curves of E. faecium in broth at pH values between 6 and 7, at temperatures of 5°C to 20°C, and for water activity values aw of 0.97 to 0.997. These growth curves were replaced with non-linear Gompertz curves for microorganism growth, the parameters of which were correlated with the temperature and pH values. A mathematical relationship to water activity could not be established since only two water activity levels have been experimentally tested and the resulting model would be highly inaccurate. The issue of water activity was resolved by the development of two separate models, one for each of the water activity values. The models correspond very well with the experimental growth curve data from which they were developed. The model for the water activity level of 0.997 was used to predict the growth of E. faecium in cow and human milks (these two fluids have practically identical water activity), and the prediction was compared to the experimental data. A good agreement between the predicted and experimental data was achieved for cow milk. With human milk, the model usually predicted a more rapid growth rate than that seen experimentally. The model was thus on the conservative side in all cases. The inhibitory agents naturally present in human milk might be responsible for the slower growth rates.

Influence of the Addition of Buckwheat Flour on Gluten Free Bread Quality and Antioxidant Capacity

M. Wronkowska, D. Szawara-Nowak, D. Zielińska, A. Troszyńska, M. Soral-Śmietana

Czech J. Food Sci., 2009, 27(10):S284 | DOI: 10.17221/607-CJFS

The diet based on gluten free products is characterised by a low content of some nutritional components such as proteins and mineral components, as well as non-nutritional but physiologically important components like dietary fibre. Buckwheat grains are a rich source of proteins, which have a high biological value due to the well-balanced amino-acids composition, although its digestibility is relatively low. The aim of the present research was to investigate the influence of buckwheat flour addition on gluten free bread quality and their antioxidant capacity. In this study, own gluten free bread formula, composed of corn starch, potato starch, salt, yeast, pectin, sugar and sunflower oil was investigated. The buckwheat flour substituted corn starch at final amount of 10, 20, 30, 40% w/w of total ingredients in gluten free bread formula. The breads were baked in electric oven at 200°C for 25 min. The bread samples were freeze-dried, ground and sieved. The sensory quality of buckwheat enhanced gluten free breads was analysed using sensory profiling (QDA) and hedonic tests. The measurement of macroelements content in the crumb was carried out using the atomic absorption spectroscopy (AAS) method (SORAL-SMIETANA et al. 2001). The antioxidant capacity (AC) of the breads was evaluated by cyclic voltammetry (CV) method and free radical scavenging activities of 67% methanol extracts against 2,2-diphenyl-1-picryhydrazyl radical (DPPH.) as DPPH Radical Scavenging Activity (DPPH RSA). All breads were analysed for their total phenolics content. The buckwheat enhancing gluten free breads were in accordance to the requirements of Polish Standards (PN-A-74123) for gluten-free bread. The sensory profiles of gluten-free breads were dependant on the amount of buckwheat flour added. The overall quality of breads was the highest for bread with 40% buckwheat flour addition. The positive correlation between macroelements content and increasing amount of buckwheat flour was observed in breads. The antioxidant capacity of buckwheat enhanced gluten free breads determined by CV and DPPH RSA was related to the amount of added buckwheat flour. The total phenolics content was positively correlated with antioxidant capacity of the breads. In summary, buckwheat flour as a natural source of minerals and antioxidant activity, and also as a structure-forming factor improving the sensory quality, can be used for preparation of new buckwheat enhanced gluten free breads.

Spectroscopic characteristics of humic acids originated in soils and ligniteOriginal Paper

Ľubica POSPÍŠILOVÁ, Naděžda FASUROVÁ

Soil & Water Res., 2009, 4(4):168-175 | DOI: 10.17221/14/2009-SWR

The aim of our work was to characterise the stability, humification degree, and principal classes of fluorophores in humic acids isolated from different matrices. Soil humic acids were isolated from arable soils and grassland that differ in the texture and moisture regimes (e.g. aquic; udic; and ustic moisture regimes). Basic soil characteristics, such as total organic carbon content, humus fractionation, cation exchange capacity, soil reaction, texture, and optical indexes were determined. The international standard method for humic acids (HA) isolation was used. Lignite represents a valuable organic substrate, with mineral inclusion situated on the transformation route from phytomass to a dehydrated, dehydrogenated, and deoxidised carbon type complex and water. One of the most attractive ways of non-energetic exploitation of lignite is humic substances source exploitation. It is known that humic acids isolated from lignite show typical bands known from other HA soil samples due to aromatic and various C-O structures. Spectroscopic characterisation has been a topic of great interest, chemical species being analysed with respect to the overall spectral characteristics of the system. Therefore UV-VIS, FTIR, and synchronous fluorescence spectroscopy (SFS) were applied in our study. The elemental composition and ash content in HA samples were determined. HA preparations were more hydrated in hydromorphic soils (Fluvi-Eutric Gleysol and Gleyic Stagnosol). The highest carbon content was found in lignite HA (57.5 weight %). Generally, carbon content was decreasing in the following order: Lignite HA > Haplic Chernozem HA > Fluvi-Eutric Gleysol HA > Haplic Luvisol HA > Gleyic Stagnosol HA > Eutric Cambisol HA. FTIR spectroscopy showed that the aromatic indexes varied from 0.61 to 0.73. HA were divided into two groups according to the aromatic and aliphatic compounds in their molecules. The highest aromatic degree and stability was found in lignite HA and Haplic Chernozem HA. Humic acids isolated from grassland and hydric soils contained more aliphatic and newly formed compounds. Synchronous fluorescence scan spectra identified aliphatic compounds in grassy and hydric soils at lower wave lengths. At higher wave lengths, identical fluorophores were detected. We registered five main peaks at: 467/487, 481/501, 492/512, 450/470, 339/359 (at Δλ = 20 nm). The peaks positions corresponded to the fluorescence behaviour of Elliot soil HA standard. Only lignite HA revealed another fluorescence peak at 492/512 nm. The peaks positions complied with the fluorescence behaviour of Leonardite standard HA. The relationships between the fluorescence indexes, colour indexes, aromatic indexes, humification degree, and elemental composition were evaluated by correlation analysis.

Plasma citrulline levels and acute cellular rejection early after small bowel transplantation in pigs

E. Honsova, A. Lodererova, P. Balaz, M. Oliverius

Vet Med - Czech, 2009, 54(5):215-222 | DOI: 10.17221/47/2009-VETMED

Small bowel transplantations (SBT) are increasingly performed to treat patients with irreversible intestinal failure or short-bowel syndrome. Histologic evaluation of small bowel allograft biopsies is important for the diagnosis of acute cellular rejection (ACR). A reliable serological marker of ACR after SBT is still unknown. Recently, citrulline was identified as a potential biomarker of reduced enterocyte mass. The aim of our study was to analyze rejection and plasma citrulline levels early after SBT in pigs. 24 pigs were used and divided into four groups. Group A, autologous SBT (n = 3) as a control group; Group B, allogeneic SBT with tacrolimus monotherapy (n = 7); Group C, allogeneic SBT immunosuppressed with tacrolimus and sirolimus (n = 8); and Group D, without immunosuppresion (n = 6). The observation period was 30 days. Mucosal biopsies were obtained on Days 0, 3, 5, 7, 10, 14, 20, 28 and simultaneously plasma citrulline levels were measured. ACR was classified according to standardized grading schema on a scale of indeterminate, mild, moderate, and severe. There were no significant differences in citrulline plasma levels between cases with mild ACR and indeterminate for ACR. A significant decline in plasma citrulline levels occurred in cases of moderate and severe rejection. Plasma citrulline levels constituted a marker of more advanced injury of small bowel epithelium.

Effects of ozonation on water quality and pikeperch (Sander lucioperca) performance in a recirculating aquaculture systemOriginal Paper

Jitka Kolářová, Jiří Křišťan, Oleksandr Malinovskyi, Josef Velíšek, Alžběta Stará, Samad Rahimnejad, Tomáš Policar

Czech J. Anim. Sci., 2021, 66(9):381-390 | DOI: 10.17221/54/2021-CJAS

The aim of this study was to examine the effects of ozonation on the water quality, and growth, blood biochemistry, antioxidant capacity and survival of pikeperch (Sander lucioperca) reared in a recirculation aquaculture system for 30 weeks. A group without ozone treatment was used as a control. The ozone application led to a significant reduction of the water chemical oxygen demand, biological oxygen demand and unsuspended solids concentration. The results revealed that an ozone treatment as a water treatment method has a positive influence on the intensive culture of pikeperch ensuring a higher survival rate (77%) compared to the non-treated control group (67.2%). Moreover, the ozonation prevented fin damage to a large extent and reduced the prevalence of an Ichthyophthirius multifiliis infection. Furthermore, the ozone application led to a reduction in the thiobarbituric acid reactive substance level and enhanced the superoxide dismutase activity in the fish gills. However, the effect of ozonation was null on the plasma biochemical parameters. Overall, these findings suggest that an ozone treatment, using adequate technological equipment to destroy the residual ozone, improves the water quality and protects pikeperch against any possible infection and fin damage in a recirculation aquaculture system.

External fixator for the treatment of narrowed pelvic canal in a catCase Report

S Pinna, C Tassani, M Rossini, F Lanzi

Vet Med - Czech, 2021, 66(8):356-362 | DOI: 10.17221/173/2020-VETMED

The aim of this study was to report the outcome of the use of an external fixator to treat a pelvic canal stenosis in a 5-month-old female cat. The cat was referred with a history of 3 weeks of intermittent signs of constipation refractory to the medical management, occurring after surgical treatment for a bilateral sacroiliac luxation and sacral fracture. The clinical examination revealed instability of the pelvis and a radiograph showed a pelvic canal stenosis and megacolon. External fixator was the method of choice to be used in this case. The manually applied tension on an external fixator resulted in a widening of the pelvic canal. At 45 days after surgery, there were no signs of constipation, and the radiological examination showed progressive bone healing. At 18 months post-op, the cat had no abnormalities both on the clinical examination and on the radiography. In conclusion, the use of an external fixator led to the widening of the pelvic canal using a minimally invasive procedure. To the authors' knowledge, this case report represents the first surgical description and clinical outcome of the widening of the pelvic canal in cats using an external skeletal fixator.

Changes in dry weight and starch content in potato under the effect of herbicides and biostimulantsOriginal Paper

Krystyna Zarzecka, Marek Gugała, Iwona Mystkowska, Anna Sikorska

Plant Soil Environ., 2021, 67(4):202-207 | DOI: 10.17221/622/2020-PSE

The aim of the study was to determine the interaction of herbicides and herbicides with biostimulants on the accumulation of dry matter and starch in potato tubers. In a three-year field experiment based on the method of randomised sub-blocks, two factors were taken into account. The first factor were potato cultivars: Bartek, Gawin, Honorata. The second factor were five methods of herbicides and biostimulants application: (1) the control object without chemical protection (CO); (2) herbicide linuron + clomazone (Harrier 295 ZC) (H); (3) herbicide linuron + clomazone (Harrier 295 ZC) and biostimulant Ecklonia maxima (Kelpak SL) - (H + K); (4) herbicide metribuzin (Sencor 70 WG) - (S); (5) herbicide metribuzin (Sencor 70 WG) and biostimulant sodium para-nitrophenol, sodium ortho-nitrophenol, sodium 5-nitroguaiacol (Asahi SL) - (S + A). The cultivars and weather conditions significantly affected the content and yields of dry matter and starch. The herbicides and biostimulants used determined the starch accumulation as well as dry matter and starch yields. Most starch in tubers (more by 3.7 g/kg) and the highest dry matter and starch yields (more by 2.87 and 1.79 t/ha, respectively), compared to the control object, were obtained after the application of the herbicide Sencor 70 WG and biostimulant Asahi SL.

Design, development and performance evaluation of small-scale fodder chopping machine for farmersOriginal Paper

Jannatul Ferdows Nipa, Md. Hasan Tarek Mondal, Md. Atikul Islam

Res. Agr. Eng., 2021, 67(3):116-122 | DOI: 10.17221/52/2020-RAE

A straw chopper is a mechanical device used to uniformly chop fodder into small pieces to mix it together with other grass and then feed it to livestock. The objective of this research was to design and develop an animal fodder chopping machine to be utilised by dairy farmers within their purchase range. The drawing of these machine parts was undertaken in AutoCAD software and the construction was performed in a local workshop. After development of this machine, performance tests were carried out on a farm. The chopping machine tests were carried out with commonly grown fodder (namely: straw, grass, and maize) in Bangladesh. The performance evaluation of the developed machine was carried out in terms of the chopping efficiency, machine productivity, and energy consumption. The economic analysis of the straw chopping machine was assessed by indicating the cost effectiveness to the poor farmers. Analysis of the data in regard to chopping efficiency and machine productivity varied from 93 to 96% and from 192 to 600 kg×h-1, respectively. The energy consumption during the chopping process ranged between 0.0025 and 0.01 kWh for the different types of fodder. The break-even point of the fodder chopping machine was 3 793 kg of cut straw and the payback period was within one year depending on the use.

Production of low protein and gluten-free cookies for phenylketonuria (PKU) and/or celiac patientsOriginal Paper

Ozen Parlak, Ayse Neslihan Dundar

Czech J. Food Sci., 2021, 39(1):29-34 | DOI: 10.17221/145/2020-CJFS

Abstract: The aim of this study was to analyse the production of gluten-free, low protein cookies, which can easily be consumed by celiac and phenylketonuria (PKU) patients. The formula was adopted to prepare the control cookies (without dried fruits) from maise starch, stabilisers, salt, sodium bicarbonate, protein-reduced milk powder, and sunflower oil. Different cookies were made by adding raisins (R), dried black currants (Cu), dried dates (D), dried apples and cinnamon (A) separately. In cookies, two different stabilisers were calculated according to starch weight [pectin (P): 0.15%, glycerol monostearate (GMS, G): 0.4%]. The effects of stabilisers and dried fruits on the physicochemical and sensory properties of cookies were investigated. The protein content was significantly higher (P < 0.05) in the cookies including R with pectin (PR), Cu with pectin (PCu), and A with pectin (PA). The amount of phenylalanine (Phe) was significantly higher (P < 0.05) in PR. The values of dietary fibre were the highest in the A cookies, while the lowest values appeared in the control (C). In the sensory evaluation (appearance, tasting properties, and affordability), it was found that PD (pectin with dries dates) was chosen as the best cookie (P < 0.05).

How does air pollution perception affect farmers' decisions on agricultural mechanisation? Evidence from rural ChinaOriginal Paper

Junkai Ma, Xintong Liang

Agric. Econ. - Czech, 2025, 71(9):475-484 | DOI: 10.17221/328/2024-AGRICECON

Air pollution is beyond an environmental or health issue. The impact of air pollution on farmers' decisions on agricultural mechanisation has always been overlooked and debate persists over subjective and objective pollution. Adopting data set from the China Labour Force Dynamics Survey, we investigate the influence of air pollution perceptions on farmers' mechanised farming. The endogeneity problem is addressed through the instrumental variable method. The consequences reveal that air pollution perceptions strengthen farm mechanisation, and reduced farming time is the key intrinsic mechanism through which perceived air pollution affects farmers' decisions on agricultural machinery. Additionally, this impact is more pronounced in male household heads and farmers in the plains. These findings render valuable policy implications for farmers chronically exposed to air pollution and for agricultural modernisation in China, including the necessity of improving air conditions and encouraging agricultural machinery services.

Domestic cat's internal carotid artery in ontogenesisOriginal Paper

H Ziemak, H Frackowiak, M Zdun

Vet Med - Czech, 2021, 66(7):292-297 | DOI: 10.17221/116/2020-VETMED

The aim of the study was to trace the presence of the internal carotid artery in the system of cerebral arteries of the domestic cat and to determine the role of this artery in supplying blood to the brain in ontogenesis. The available publications provide ambiguous or even contradictory information. The authors of some studies claim that there is no extracranial segment in the domestic cat's internal carotid artery. Other authors reported the internal carotid artery in the arterial pattern of the encephalon base. The study was conducted on sixty-one domestic cats: fifteen foetuses, sixteen juvenile cats, and thirty adult cats were analysed. The internal carotid artery - a vessel with a relatively large lumen - was fully preserved in all the foetuses and most of the juvenile animals. This artery was not complete with regard to the adults and some juvenile individuals, because it had lost the extracranial segment as a result of the obliteration process. A precise description of this area is not only of biological, but also of clinical, significance. The knowledge of the anatomical structure of cerebral vessels is particularly important to correctly interpret images obtained during diagnostic tests and to conduct surgical procedures correctly.

Clinical and immunohistochemical findings of splenic mast cell tumour in a cat: A case reportCase Report

S Lee, MS Kang, Y Jeong, Y Kim, HH Kwak, EW Choi, S Choi, I Park, JY Chung, JH Choi, JO Ahn

Vet Med - Czech, 2021, 66(11):498-502 | DOI: 10.17221/11/2021-VETMED

A 6-year-old, spayed, female, domestic shorthair cat presented with a 4-month history of chronic intermittent vomiting and anorexia. The haematologic results indicated moderate anaemia and a circulating mast cell population. The abdominal radiography revealed a markedly enlarged spleen. The cytological analysis of the spleen showed a uniform population of mast cells, and a diagnosis of systemic mastocytosis (splenic mast cell tumour with mastocytaemia) was made. This diagnosis was subsequently confirmed by the histopathological examination of the spleen. The immunohistochemistry for KIT showed KIT pattern II (focal cytoplasmic expression). A splenectomy and chemotherapy with vinblastine and prednisolone resulted in remission of the anaemia and other clinical signs. This case report highlights the importance of cytological evaluations of peripheral blood smears and/or aspirates of enlarged spleens for diagnosing splenic mast cell tumours and for quickly initiating the appropriate treatment.

The use of the game theory in the management of agroecosystem servicesOriginal Paper

Ernesto Mesa-Vázquez, José A. Aznar-Sánchez, Óscar González-Yebra, Miguel A. Gómez-Tenorio

Agric. Econ. - Czech, 2025, 71(11):618-627 | DOI: 10.17221/86/2025-AGRICECON

Agroecosystems provide a number of ecosystem services that are essential to human well-being.  The valuation of these services by stakeholders offers important information that can be used to manage them more efficiently. In agroecosystems, individual stakeholder preferences can be heterogeneous and even opposing. This paper puts forward a novel analytical framework based on game theory to integrate the valuation of ecosystem services by different stakeholders into agroecosystem management. To illustrate it, the agricultural region of Los Vélez (south-eastern Spain) is used and three game modalities are applied (prisoner’s dilemma, common-pool resource game and battle of the sexes). Results indicate that the use of game theory contributes to more effective conflict resolution between stakeholders with different interests and priorities, making it easier to reach consensus on optimal management strategies. This approach can guide policymakers in the design and implementation of socially accepted agroecosystem management policies.

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