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VLIV SUMY EFEKTIVNÍCH TEPLOT NA AKUMULACI ZÁSOBNÍCH LÁTEK V KOØENOVÉM SYSTÉMU VOJTÌ©KY SETÉ (MEDICAGO SATIVA L.)

Josef Hakl, Jaromír ©antrùèek, Pavel Fuksa, Josef Kalista

Acta Univ. Agric. Silvic. Mendelianae Brun. 2008, 56(2), 81-86 | DOI: 10.11118/actaun200856020081

The aim of this study was to investigate the relation between growing degree day method and accumulation of root reserve saccharides before over wintering by alfalfa (Medicago sativa L.) in the condition of Czech Republic. In 2002-2004, the field experiment was conducted at the Research station of the Czech University of Life Sciences in central Bohemia. The interval between summer and last autumn harvest was 40-50 days or 60-70 days, respectively. These intervals were expressed as cumulative growing degree-days (GDD) for each year. The plants were sampled in each autumn with four replicates for each variant; the average depth of sampling was 150 mm. The weight of roots, amount of starch, and water soluble saccharides (WSC) per m2 was determined. The total accumulation of root reserve saccharides was determined mainly by conditions during all vegetation period. The length of the interval or cumulative GDD influenced only variation of this basic amount. The GDD was corresponded better with starch content whilst WSC was more related to length of the interval. In central Bohemia condition, the GDD 600-700 °C was preliminary determined for maximal accumulation of root reserve saccharides. The GDD above this level did not significantly increase the root reserve accumulation. For exact verify of this model, other experiments in more sites are needed.

VLIV LEPENÍ NA MNO®STVÍ EMISÍ VOC

Petr Èech

Acta Univ. Agric. Silvic. Mendelianae Brun. 2008, 56(4), 29-36 | DOI: 10.11118/actaun200856040029

The study deals with the influence of urea-formaldehyde glue and veneered bolstering on technological operation veneering on quantity of emission VOCs (volatile organic compounds).
The so-called Volatile Organic Compounds (VOC) are among the largest pollution sources of both the internal and external environments.
VOC is defined as emission of any organic compound or a mixture thereof, with the exception of methane, whereby the compound exerts the pressure of 0.01 kPa or more at the temperature of 20 °C (293.15 K) and reaches the corresponding volatility under the specific conditions of its use and can undergo photochemical reactions with nitrogen oxides when exposed to solar radiation.
The effects of VOC upon environment can be described by equation:
VOC + NOx + UV radiation + heat = tropospheric ozone (O3).
In this work there were tested background working environment in various parts of multi-storeyed press, next was judged emissive charge of veneered device and used glue. We used surface material such as chipboard. We used urea-formaldehyde glue KRONOCOL U300 on technological operation veneering.
The VOC emissions from the wooden surfaces with or without finishing were tested in the Equipment for VOC Measuring with a small-space chamber. This equipment was installed in and made available by the Institute of Furniture, Design and Habitation. The small-space chamber is suitable for testing small parts of wood products. The device equipped with small-chamber satisfies all conditions mandated in the standard ENV 13 419 DIN -V-ENV 13 419 "Determination of the emissions of Volatile organic compounds".
The VOC emissions were collected in columns with sorbent Tenax TA. We analyzed the columns with the VOC emissions by: the gas chromatography in conjunction with mass spectrometer and Direct Thermal Desorption.

Vyhodnocení nìkterých ukazatelù pitné vody ve vybraných, rùznì hospodaøících chovech dojnic v Èeské republice

Václava Genèurová, Oto Hanu¹, Libor Janù, Antonín Macek, Marcela Vyletìlová

Acta Univ. Agric. Silvic. Mendelianae Brun. 2008, 56(4), 57-76 | DOI: 10.11118/actaun200856040057

The paper evaluates drinking water quality on selected dairy farms on the territory of the Czech Republic. The drinking water samples were collected in the farm milk storage rooms of 30 farms with subsequently made analyses. The pre - selected chemical and microbiological indicators were stated according to the regulation No. 252/2004 Coll. (pH, conductivity, chemical oxygen demand, colour, turbidity, Fe, ammonia ions, nitrites, nitrates, colony count growing at 36 °C, colony count growing at 22 °C, coliform bacteria, Escherichia coli, Ca, Mg, Na, K, Zn, Cu, Mn, Pb, Cr and Ni). The statistical evaluation was performed in the obtained data file and these data were compared with the limit values given by the regulation. The nitrate content ranged between 1 and 40.7 mg L-1 with an average of 15.6 mg L-1. The pH values varied from 5.71 to 8. The chloride concentration geometrical means was 7.57 mg L-1. The Ca average concentration 58.5 mg L-1 was in the middle of the recommended interval 40-80 mg L-1. The geometric means in Mg content was 7.9 mg L-1 being under the recommended value 20-30 mg L-1. The Cu, Pb, Cr and Ni limit values were not exceeded. The limit values in microbiological analyses were exceeded 18x in coliform bacteria, 10x in enterococci, 5x in Escherichia coli. The microbiological colonies growing at 36 °C exceeded limit 9x, those growing at 22 °C 5x.
Further, differences are compared between the organic and conventional farms, and between farms producing milk in different type of LFAs (less favourable areas) and farms not included in these areas. The difference found out between the chloride concentrations in organic (6.56 mg L-1) and conventional farms (18.2 mg L-1; p < 0.05) was statistically significant. Locality or altitude, where a given far is situated, were another classifying criterion. A significant dependence was only found out in nitrate content, which decreased (p < 0.05) with increasing altitude (the correlation coefficient value -0.39). It can correspond with the soil use decrease - a lesser fertilization intensity. Statistically significant differences were found out in hardness value as well as in Ca, Mg contents connected with that in all reference criterions. The hardness was clearly lower (1.13 mmol L-1) in organic farms as compared with concentration 2.27 mmol L-1 in conventional ones. It is, however, only a supplementary indicator according to the respective regulation. No statistical significance was found among microbiological finding values in any case.

Kvalitativní charakteristiky a antioxidaèní vlastnosti kultivarù brokolice (Brassica Oleracea L. var. italica Plenck)

Marek Gajewski, Pawe³ Szymczak, Marta Gorczyca, Maja Madejska

Acta Univ. Agric. Silvic. Mendelianae Brun. 2008, 56(1), 91-96 | DOI: 10.11118/actaun200856010091

Quality traits of three broccoli cultivars, which were grown for autumn crop was determined: 'Chevalier' F1, 'Milady' F1 (cultivars of Dutch origin) and 'Cezar' F1 (of Polish origin). Immediately after harvest sensory quality of broccoli was evaluated, using the quantitative descriptive analysis method (QDA). In 'brainstorming' session there were chosen 14 attributes (profiles) concerning smell, texture, taste / flavour. Overall quality impression was also scored and hedonic test of broccoli liking was performed. Other quality traits determined were: antioxidant activity, total carotenoids content, vitamin C content, colour parameters in CIE L*a*b* system. These traits were determined separately for florets and stems of broccoli plants, both of which are usable parts of this vegetable. Results showed that investigated cultivars differed in respect of quality traits concerning sensory attributes, antioxidant activity, carotenoids content, vitamin C content and colour parameters. Results showed also that florets of broccoli performed higher antioxidant activity than stems. Carotenoids content in broccoli cultivars was much higher in florets than in stems, but vitamin C content was on similar level in florets and stems of the plants. Florets and stems of all broccoli cultivars differed much in respect of colour parameters - lightness, greenness and yellowness.

VLIV ZRÁNÍ NA TEXTURNÍ VLASTNOSTI EIDAMSKÝCH SÝRÙ

Táòa Lu¾ová, ©árka Povolná, ©árka Nedomová, K. ©ustová, Veronika Bla¹ková

Acta Univ. Agric. Silvic. Mendelianae Brun. 2008, 56(2), 107-114 | DOI: 10.11118/actaun200856020107

In this study were evaluated the Edam cheeses with fat content in dry matter 30% and 45% (w/w) produced using two different starter cultures YY and LL during 6 months of ripening. Sampling times were 26, 54, 89, 117, 146 and 180 days after production. The surface and central parts of cheeses have been evaluated separately.
Cheese texture was analysed by using a Tira test 27025. The force needed to compress the sample was recorded (N).
Ripening time had significant effect on rheological characteristics of the cheeses. The improvement of texture was related to the ripening time. At the beginning of ripening (1st month), there is a significantly higher hardness on surface layer of the cheese in samples of cheeses with 30% fat in dry matter. This is the case in both cultures. This difference has evened out after 2 months of ripening. The force needed to compression of the centrepiece of cheese with lower fat content in dry matter was 30.96 N and of cheese with higher fat content in dry matter 36.51 N, while after 60 days of ripening of cheese with lower fat content in dry matter it was 50.56 N and of cheese with higher fat content in dry matter 63.23 N.
The influence of two different types of starter culture on the texture was evaluated. It was found out that after 60 days of ripening of cheese with 45% (w/w) fat in dry matter there was significant difference (P ≤ 0.01) in the firmness between cheese with starter culture YY (force 63.23 N) and LL (force 48 N). In every Edam sample after 3 months of aging (optimal ripe Edam) there was no dependence on the type of starter culture. After 120 days of ripening there was a significant difference in firmness of cheese with culture YY (44.58 N) and LL (33.61 N).
Satistically significant difference (P ≤ 0.05) between the firmness of the surface and the central parts of the cheese was not found after one month of ripening.

VLIV ZPÙSOBU A DÉLKY SKLADOVÁNÍ NA VLHKOST A SENZORICKOU JAKOST TRVANLIVÝCH SALÁMÙ

Hana ©ulcerová, Jiøí ©tencl, A. ©ulcová

Acta Univ. Agric. Silvic. Mendelianae Brun. 2008, 56(4), 183-196 | DOI: 10.11118/actaun200856040183

Heat-treated salamis "Vysoèina" were produced with standard way in a meat factory; their diameter was 55 mm. Samples were stored under laboratory conditions at different temperatures: 5, 10, 15, 20, and 25 °C and sensory analysed every week during one month storage. The dry matter (d.m.) was measured, too. Descriptors of general appearance, sausage casing, texture, cut surface, dry edge, smell, taste, and salty were monitored. Biggest changes were in descriptors general appearance and sausage casing (P < 0.001) and also in dry edge (P < 0.010) during the month period. Germs of moulds were found only at 5 and 10 °C. Rapid increase of d.m. in samples was noticeable in the first week of the storage time. It was 3 % d.m. at 5 °C and 11 % d.m. at 25 °C. Increase of d.m. of salamis continues slowly in the next three weeks period; the total difference was about 10 % d.m. in the temperature range measured. Decrease of d.m. at 5 °C was noticed in the last week of the measurement. The difference was 3.5 % d.m. This change means that the equilibrium moisture content of the samples of salamis has been reached at the temperature 5 °C. The best sensorial quality of salamis "Vysoèina" was in the storage temperature ranged from 15 to 20 °C.

PENTOSANY VE VZTAHU K JAKOSTI ®ITA

Jindøi¹ka Kuèerová

Acta Univ. Agric. Silvic. Mendelianae Brun. 2008, 56(4), 115-120 | DOI: 10.11118/actaun200856040115

The aim of this contribution is the evaluation rye pentosans in the relation to protein content, Falling number, content of maltose and amylograph values. Population and hybrid varieties of rye were grown during 2003-2005. Trials were situated in three different locations of the Czech Republic - Hradec nad Svitavou, Krásné údolí and Staòkov. Content of pentosans varied between 6.60-9.21 %. The highest content of pentosans (average of the three years and three locations) achieved the hybrid variety Picasso (8.11 %), which had the highest Falling number (235.8 s) and amylograph maximum (625.5 AJ), too. The location Hradec nad Svitavou (8.21 % pentosans) was the best and the year 2003 (8.34 % pentosans) was the most positive.
The results were affected by soil and weather conditions which have influence on protein content. Between the pentosans content and the Falling number a high positive correlation (r = 0.523, P < 0.01) was found and nonsignificant negative correlations with protein content (r = -0.070) and amylograph maximum (r = -0.072). Remarkable difference in the Falling number and amylograph maximum between population varieties (Daòkovské nové a Selgo) and hybrid variety (Picasso) were found.

ANALÝZA KONDENZÁTU ZE SU©ENÍ DØEVA V KONDENZAÈNÍ SU©ÁRNÌ ØEZIVA

Ale¹ Dejmal, Jiøí Zejda

Acta Univ. Agric. Silvic. Mendelianae Brun. 2008, 56(5), 31-38 | DOI: 10.11118/actaun200856050031

Some associated substances which are not innate to the drying wood may be evaporated together with moisture to the surrounding environment during the drying process. These substances in high concentrations can be dangerous and have negativ influence on the living environment. This work deals about the results of expertize condensation arose during the drying of spruce wood. Wet spruce lumber was dried by dehumidification system with low temperature conditions (55 °C). The analysis of condensate fluid (water) collected during the first part of drying process shows on a content of some volatile organic compounds. The condensed fluid was get from drying of spruce timbre of 24 mm of width. The timbre was dried in a small semi industrials scale drying kiln when the moisture of the lumber was 56% in the beginning of the process. Volume of the lumber under examination was 2.2 m3. The condensate fluid was originally from down pipe. The condensate fluid was collected during the initiatory phase of the drying, four hours after the initiation of the drying process itself. First, the value of pH of the condensate fluid was measured. Determination of volatile organic compounds was done by accredited method SOA-16. The concentration of these substances were under the limits set in the statute No. 61/2003 Law Digest.

VLIV SILÁ®NÍCH ADITIV NA DYNAMIKU, KVALITU A AEROBNÍ STABILITU FERMENTAÈNÍHO PROCESU KUKUØIÈNÝCH SILÁ®Í

Václav Pyrochta, Libor Kalhotka, Petr Dole¾al

Acta Univ. Agric. Silvic. Mendelianae Brun. 2008, 56(1), 157-164 | DOI: 10.11118/actaun200856010157

In the experiment, the effect of additives supplementation on the fermentation quality of corn silage was examined, compared with the untreated control ( K). The aditive "A" contained bacterial component of (Propionibactrium acidipropionici - MA126/4U 3*1010 and Lactobacillus plantarum - MA18/5U). The effective substances of bacterial inoculants "B", selected were bacterial strains of (Lactobacillus casei ssp. rhamnosus LC - 705 DSM 7061 4*1011, Propionibacterium freudenreichii spp. shermanii JS DSM 6067 2-4*1011). There were used as effective substances of bacterial inoculants "C" lactic bacteria and enzyme (Lactobacillus plantarum CCM 3769 1.67*1010, Lactococcus lactis CCM 4754 1.67*1010, Enterococcus faecium CCM 6226 1.67*1010, Pediococcus pentosaceus CCM 3770 1,67*1010, cellulase, hemicellulase, sodium benzoate). They were applied in the dose of prescript by producer. At conservations with all aditivum were statistically significant (P < 0.01) increase of lactic acid formation from 55.31±9.72 g/kg DM of control silage to 59.60±10.84 g/kg DM aditivum "A", 59.36±10.04 g/kg DM aditivum "B" rather to 60.74±9.90 g/kg DM aditivum "C". Aditives "A" and "B" were statistically significant (P < 0.01) increase propoinic acid and total fermentation acid content in silages occured. The fermentation characteristics in the microbial aditivum silages by us were more favourable. The date of fermentation was statistically significant (P < 0.01) increase the contents of acetic acid from 45.49±2.83 g/kg DM of 4st day to 63.07±4.25 g/kg DM of 32ndday rather to 67.70±2.94 g/kg DM of 64st day. There were statistically significant (P < 0.01) increase contents of acetic acid and total acid content. The date of fermentation was statistically significant (P < 0.01) degressive of pH.

VLIV PØÍDAVKU CHEMICKÉHO KONZERVAÈNÍHO PØÍPRAVKU NA KVALITU SILÁ®E LUPINY

Jiøí Skládanka, Petr Dole¾al

Acta Univ. Agric. Silvic. Mendelianae Brun. 2008, 56(2), 139-146 | DOI: 10.11118/actaun200856020139

The aim of this study was to evaluate the effect of a chemical preservative supplementation on the quality of lupine silage as compared with untreated controls. Fresh green Lupine (Lupines lupine), variete Juno, dry matter content 187.15 g/kg at full waxy stage of maturity were chopped to the legth of cut ca 30-50 mm. The crop was artificially wilted for a periody 24 h and ensiled as described above. Lupine were ensiled for 98 days in laboratory silos, capacity about 4 l alone or with supplementation of chemical preservative 3 and 6 l/tone forage respectively). The relatively mean WSC content and the low buffering capacity of lupine crop provided for a good preservation with the chemical preservative.
The best quality of fermentation process and nutritive value was found in silages with the supplement of acid mixtures dosed at 6 l/t since they showed not only a better content of net energy (NEL) and CP but also a significantly higher ethanol content, a more favourable RDP content and a higher starch content than the control. The supplement of preservatives resulted in the increased DM content in stored silage, in the increased escape of silage effluents and in the inhibited (P < 0.01) formation of acetic acids (19.8±2.17 g/kg DM) in comparison with control silage. In chemical treated silages (3 l/t) was also increased level (P < 0.01) of lactic acid (116.9±2.61 g/kg DM) and total acids in kg of dry matter (143.4±3.64 g/kg), but decreased level of pH value (4.03±0.01), acidity water extract (KVV-1221.1±11.51 mg KOH/100 g silage), titration acidity (FT-0.107±0.002), and of NH3 content (664.1±7.51 mg/kg DM).

Mo¾nost pou¾ití su¹ených organických a organominerálních hnojiv jako náhrady za chlévský hnùj u raného kvìtáku

Stanislav Boèek, Ivan Malý, ©árka Patoèková

Acta Univ. Agric. Silvic. Mendelianae Brun. 2008, 56(2), 21-30 | DOI: 10.11118/actaun200856020021

Experiments were conducted in field plots to evaluate the effects of three alternative dried organic, or organomineral, fertilizers on yield and quality of the early maturing cauliflower variety, 'Gameta'. Plots were established in ®abèice (South Moravia, Czech Republic) in 2005-2007. We used the following fertilization treatments: Agormin T, Agro, Dvorecký agroferm, cattle farmyard manure and solo mineral fertilizers, compared to an unfertilized control. All plots, except the control, were fertilized to achieve the same level of nutrients, as determined by the soil analyses and the chosen target yield. We assessed the following traits at harvest: weight of above-ground mass, marketable yield, head weight and head diameter. Levels of ascorbic acid, nitrates, dry matter and mineral ions (potassium, sodium, calcium and magnesium) were measured in the heads. Agormin T significantly increased the weight of above-ground mass and total marketable yield. All organic fertilizers significantly increased head weight and head diameter in comparison to both the unfertilized control and mineral fertilizers. Ascorbic acid levels were not significantly affected by the fertilizers. The highest value of ascorbic acid was observed for farmyard manure, the lowest for Dvorecký agroferm. Dried fertilizers had no positive effect on ascorbic acid levels and total solids, as compared to farmyard manure. In contrast, Agormin T resulted in significantly lower levels of dry matter. Solo mineral fertilization resulted in the highest levels of nitrates in cauliflower heads. Fertilization with Agro and farmyard manure significantly increased the levels of nitrates in heads, as compared to the control, but all values were under the hygienic limit. The different fertilizer treatments did not have any significant effects on the levels of mineral cations. The dried granulated fertilizers Agormin T, Agro and Dvorecký agroferm were shown to be good alternatives to bulky farmyard manure for early ripening cauliflower. Only Agormin T decreased the dry matter content in heads.

POSOUZENÍ KVALITY ÈERSTVÉHO A SILÁ®OVANÉHO PIVOVARSKÉHO MLÁTA V PRÙBÌHU SKLADOVÁNÍ

Vladimír Majer

Acta Univ. Agric. Silvic. Mendelianae Brun. 2008, 56(4), 247-256 | DOI: 10.11118/actaun200856040247

The main objective of this paper is to assess the changes of content of essential organic nutrients, yeasts and moulds and effect of aerobic fermentation when the fresh (untreated) and treated brewers grains (BG) is stored in the stall conditions. Both the fresh brewers grains from Radegast brewery and that treated by mixture of sodium benzoate (22.9%) sodium propionate (8.3%) and following 90 days anaerobic fermentation were mounded in the entrance of stall and tested in two tests, one during the winter period in February, the other one during the summer period in June. Influence of treatment was evident on the process of fermentation, levels of the nitrogen-free extract substances (NFES) and number of forming colony units (FCU) of moulds in the winter period. The fermentation activities in both tested masses were documented, however the decrease of intent of NFES in treated variants was highly conclusive (P < 0.01) lower than that of untreated variants. Stagnation of increase of formol titration in treated BG matches the same tendency. Significant (P < 0.01) limitation of mould growth was noted at treated BG, the number of FCU of moulds stagnated since 1st to 5th to day of testing. On the other hand the number of FCU of moulds in untreated BG was redoubled after 4 days since the start of testing. Treatment influenced monitored parameters above all in the early gout after the start of testing. NFES content in untreated BG in February statistically highly conclusive (P < 0.01) fell from average values 502.99 ± 8.704 in 1st day of testing on 437.533 ± 18.877 g.kg dry matter in 6th day of testing while at treated BG was fall behind the same period only conclusive (P < 0.05). There was ascertained highly conclusive growth (P < 0.01) of level of formol titration from 0.004 ± 0.001 in 1st day to 0.178 ± 0.038 in 6th day of the same testing at untreated BG, while the level of formol titration stagnated at treated BG. In June content of NFES at untreated BG statistically conclusive (P < 0.05) declined from 455.578 ± 9.515 in 1st day on 432.92 ± 9.515 g.kg dry mater in 5th day of testing. Near NFES content at treated BG statistically conclusive (P < 0.05) declined as late as 7th day. Alike formol titration level at untreated BG surged from 0.008 ± 0.001 in 1st day on 0.087 ± 0.036 in 5th day, on the contrary at treated BG come to statistically highly conclusive (P < 0.01) growth as late as 7th day of testing.
Both monitoring demonstrate that the treatment of BG by mixture of sodium benzoate (22.9%) and sodium propionate (8.3%) and its subsequent 90 day anaerobic fermentation will reduce activity of moulds and fall of included NFES and retarded resolution of protein on subsequent manipulation up deliver form silage bag and during a short-period storage in stall.

Slo¾ení a toxicita sinic rybníkù ji¾ní Moravy v závislosti na intenzitì rybáøského hospodaøení

Radovan Kopp, Andrea Ziková, Jan Mare¹, Stanislav Navrátil, Ondøej Adamovský, Miroslava Palíková

Acta Univ. Agric. Silvic. Mendelianae Brun. 2008, 56(5), 111-118 | DOI: 10.11118/actaun200856050111

During the vegetative period of the year 2005 (June-October) we carried out hydrobiological and hydrochemical monitoring of selected ponds inhered in Southern Moravia in relation to different fishery management intensities. Water temperature, dissolved oxygen content, pH, conductivity and water transparency were monitored directly at taking place, N-NH4+, N-NO2-, N-NO3-, P-PO43- content and chlorophyll-a concentration were measured in hydrochemical laboratory. At the same time, water samples for taxonomical analyses of phytoplankton and assessment of toxin content of cyanobacteria were taken. All ponds were characterized by low water transparency, high values of pH, N-NH4+, P-PO43- and high chlorophyll a concentration. We detected maximum concentration of 18.7 µg.l-1 microcystins in ponds dominated by the species Microcystis aeruginosa. Total microcystin concentration in water of all ponds with dominance of pikoplanktonic cyanobacteria were below detection limit (LOD < 0.125 µg.l-1). The dominance of cyanobacteria species shifts from coccal (especially genus Microcystis) to small-colonial pikoplanctonic (genus Aphanocapsa, Aphanothece) and to single-filamentous (genus Planktothrix, Limnothrix, Pseudanabaena) cyanobacteria related to increasing fish stock density.

Vliv rychle fermentovaného praseèího hnoje na výnosové parametry brokolice a vybrané pùdní parametry

Peter Kováèik, Anton Uher, Tomá¹ Lo¹ák, Peter Takáè

Acta Univ. Agric. Silvic. Mendelianae Brun. 2008, 56(5), 119-124 | DOI: 10.11118/actaun200856050119

The effect of Difert (a pig manure fermented by caddices of domestic flies produced on sawdust litter) on broccoli yield parameters and selected soil parameters were investigated on gleic fluvisol in a small-plot field trial localized at area of Slovak University of Agriculture in Nitra (48°18' N, 18°05' E).
The results showed that Difert applied in doses of 250 kg N.ha-1 and 350 kg N.ha-1 acted positively on the yields of fresh primary broccoli roses. However, the results are not statistically significant. Also a positive effect on N, P, K, Ca, Mg contents in broccoli roses was recorded. Difert has a moderate alkalizing effect on soil and increases the content of Cox in the soil. Moreover Difert insignificantly decreased the content of vitamin C and significantly increased the content of nitrates in broccoli roses, but the worst qualitative effect on broccoli parameters was detected by applying mineral N fertilizers, which significantly increased the content of nitrates in broccoli roses and insignificantly decreased the vitamin C content. However, it resulted in the highest broccoli yields. The application of mineral N fertilizers had a negative effect on the total content of carbon in the soil as well.
The effect of Difert on broccoli yield and soil parameters refers to the feasibility of reducing the maturing period of the manure from 6 months to 1 week, in order to decrease the manure storage capacities.

Vliv pastvy ovcí na obsah energie a organických ¾ivin ve stepních porostech Národní pøírodní rezervace Mohelenská hadcová step

Pavel Veselý

Acta Univ. Agric. Silvic. Mendelianae Brun. 2008, 56(1), 229-236 | DOI: 10.11118/actaun200856010229

The aim of this research was to assess the implications of sheep grazing for the nutritional value of the vegetation in the Mohelno Serpentine Steppe National Nature Reserve (NNR). A free pasture controlled by an electric fence was practised from 1997 to 1998. The German Merino sheep were grazing on an area of 4.25 and 6 ha with a pasture load of 6.8-9.4 sheep per 1 ha in 1997 and 6.7-8.7 sheep per 1 ha in 1998. The steppe vegetation samples were collected from five different sites reflecting the phytocenological composition typical of the individual steppe areas. The vegetation samples were collected on an area of 3×1 m2 during the growing season at two-week intervals. The collected samples were tested for the amount of dry matter, fibre, nitrogenous substances, fat, ash, nitrogen-free extractive substances (NFES), gross energy (GE), metabolic energy (ME), lactation net energy (LNE), fattening net energy (FNE), PDIN and PDIE (PDI - referring to the factually digestible nitrogenous substances in the small intestine of the ruminants). During pasture there was a decrease in the dry matter levels but its average levels remained high (35.45-46.78%). The effect on the nitrogenous levels became apparent (P < 0.05) mainly in the second year of grazing (10.00-10.94% compared to 11.64-19.35% in the vegetation dry matter). However, in comparison with the pasture vegetation the effect remained less significant. A similar situation was observed in relation to the fluctuation of PDIN and PDIE (64.60-70.71 compared to 75.18-124.98 g/kg of the dry matter and 79.03-82.71 compared to 89.41-29.27 g/kg of the dry matter respectively). The fat levels (3.80-4.02%) were not affected by the site (P < 0.05) but the specific utilization. The grazing brought about a marked increase in the fat levels (P < 0.001). The amount of the fibre during the first year was affected only in terms of its decreased site variability (29.60-31.31%). The conclusive evidence (P < 0.05) of the decrease did not appear until the second year of grazing (21.76-27.88%). In the course of the pasture the ash levels identified in the dry matter were fluctuating between 8.74-10.19% depending on the site conditions and the form of utilization. Considerably high levels (P < 0.05) were recorded on more intensely grazed areas. NFES levels in the step areas (45.16-47.26%) were steady both in terms of the site conditions and the form of utilization.
The energy levels did not reflect the site variability. The ME, LNE and FNE levels (9.39-9.79; 5.52-5.80 and 5.34-5.69 MJ per kg of the dry matter respectively) were affected by the form of utilization. During the pasture the site variability of the energy levels decreased. There was also a substantial increase in the amount of energy established in the dry matter, which rose to the levels usual for pasture vegetation.

VLIV OBSAHU HRACHU V DIETÁCH NA STRAVITELNOST DUSÍKATÝCH LÁTEK U PRASAT

Jan Vavreèka, Miroslav Sikora, Petr Mare¹, Ladislav Zeman

Acta Univ. Agric. Silvic. Mendelianae Brun. 2006, 54(2), 139-146 | DOI: 10.11118/actaun200654020139

The aim of these balance experiments was to analyse the level of feeding pea varieties GOTIK and ZEKON on the digestibility of protein in growing pigs. Variety ZEKON has low content of antinutritional factors in comparison with variety GOTIK. The tentative mixtures contained following amounts of pea (Experiment A): 0.1%, 9%, 18% and on the whole were observed six diets. The apparent digestibility of protein with the diet containing ZEKON was 81.1±4 in group SZ0.1, 81.78±2.47 in group SZ9 a 78.94±4.14 in SZ18 and with the diet containing GOTIK in comparison with ZEKON lower, namely 79.9±4.12 in group SG0.1, 76.02±5.77 in SG9 a 78.18±2.28 in SG18. We observed only one statistical significant value between group SZ9 and SG9 (P

VYPOVÍDACÍ SCHOPNOST UKAZATELE EVA VE VZTAHU K INFORMAÈNÍMU OBSAHU TRADIÈNÍCH VÝKONNOSTNÍCH UKAZATELÙ U PODNIKÙ ÈESKÉHO POTRAVINÁØSKÉHO PRÙMYSLU

Gabriela Chmelíková

Acta Univ. Agric. Silvic. Mendelianae Brun. 2006, 54(6), 77-84 | DOI: 10.11118/actaun200654060077

The topic of this paper is motivated by the increasing popularity of Economic Value Added (EVA) and by the need to make the managing process of Czech agribusiness firms more efficient. Through adoption of EVA principle, the proponents of EVA argue, that EVA will lead to increased efficiency in the management and allocation of all assets and hence increased shareholder value. Though from the theoretical point of view EVA is seen as a superior performance metric, the results of the most empirical studies do not support this claim. One of the standard argument against EVA superiority results from the statistical survey of the relationship between EVA and traditional performance measures. Despite of the results of the most empirical studies this paper assumes (with regard to the specifics of Czech food processing sector) a difference in information content of EVA and traditional performance metrics. The intent of this article is to provide a simple regression test of the hypothesis that between EVA and traditional performance metrics is not tight linear dependency, which would point out that EVA has the same information content as traditional performance measures. The regression results indicate in all cases a positive correspondence between EVA and financial performance metrics with very low dependency of EVA on the financial metrics, which supports the examined hypothesis.

Porovnání mléèné u¾itkovosti a nìkterých reprodukèních parametrù hol¹týnských krav importovaných ze ©védska s jejich vrstevnicemi v Polsku

Ewa Czerniawska-Pi±tkowska, Maciej Szewczuk, H. Kamieniecki, M. Adamski, A. Bru¶, Daniel Falta

Acta Univ. Agric. Silvic. Mendelianae Brun. 2007, 55(1), 39-44 | DOI: 10.11118/actaun200755010039

The general aim of the present work was to compare dairy performance and some reproductive parameters of Holstein-Friesian (HF) cows imported from Sweden as an in-calf heifers, and their age mates in Poland. The animals were kept freely on the deep litter on the farm owned by Agro-company "Witkowo" and feeding was based on TMR (total mixed ration) system during whole year. All ration's ingredients (bulky feed, concentrate, miscellaneous additives) were mixed and fed as all-mash. The feed ration depended from the physiological condition of a cow and it was composed of corn and grass ensilage, mash concentrate, crushed corn meal, brewer's grains and beet pulp.
Cows imported from Sweden as in-calf heifers obtained higher milk, fat and protein yield in both lactations comparing to home cows. Significant statistical differences were observed for kg of milk, kg of protein, for FCM (P

Mikrobiologická detekce probiotických mikroorganismù ve fermentovaných mléèných výrobcích

Radka Burdychová

Acta Univ. Agric. Silvic. Mendelianae Brun. 2007, 55(2), 15-20 | DOI: 10.11118/actaun200755020015

A number of health benefits have been claimed for probiotic bacteria such as Lactobacillus acidophilus, Bifidobacterium spp. and Lactobacillus rhamnosus. Because of the potential health benefits, these organisms are increasingly incorporated into dairy foods. However, to reach health benefits, the concentration of probiotics have to be 106 CFU/g of a product. For assessing of required probiotic bacteria quantity, it is important to have a working method for selective enumeration of these probiotic bacteria.
Five bacteriological media were evaluated to assess their suitability to selectively enumerate Streptococcus thermophilus, Lactobacillus rhamnosus, Lactobacillus acidophilus and Bifidobacterium spp. Bacteriological media evaluated included Streptococcus thermophilus agar, pH modified MRS agar, MRS-vancomycine agar and BSM (Bifidus selective medium) agar under different culture conditions.
Seven selected fermented milk products with probiotic culture were analyzed for their bacterial populations using the described selective bacteriological media and culture conditions. All milk products contained probiotic microorganisms claimed to be present in declared quantity (106-107/g).

Pøekroèení kritických úrovní ozonu na stanici monitoringu èistoty ovzdu¹í v areálu BZA MZLU v Brnì v letech 2001 a¾ 2006

Jan Svoboda

Acta Univ. Agric. Silvic. Mendelianae Brun. 2007, 55(2), 123-130 | DOI: 10.11118/actaun200755020123

Cumulative effects of agricultural crops exposition, forests and other ecosystems for ozone concentration above the threshold is characterized by exposition index AOT. According to experst for EHK, the recent level is 40 ppb. Very dry summer in 2006 and 2003 created good conditions for photochemical reaction as well as ozone transport in Central Europe. Such years can be taken as an example in connection with expected concentration of ground ozone (as a result of global warming). Amount of ozone in troposphere is measured in Botanic garden and MZLU arboretum areas since 2001 by analyzator 41M-LCD. Ozone course correlates with course of air temperature from end of May till end of August. Coefficient of correlation for 2006 was 0,872 and year 2003 was 0,777, which is statistically significant. Similar course was found for summer months of 2004 (0.703), a bit lower as 2006. There were exceeded imission limits for vegetation protection and AOT40 in 2003 and 2004. There were the highest values for vegetation protection in 2006, 2003 and 2004. Immision limits exceeded 90 days in 2006, 61 days in 2003 and 53 days in 2004.

Vliv redukce listové plochy na výnos a kvalitu cukrovky (Beta vulgaris L. var. altissima Döll)

Radim Cerkal, Jan Dvoøák, Karel Vejra¾ka, Jiøí Kamler

Acta Univ. Agric. Silvic. Mendelianae Brun. 2007, 55(5), 37-44 | DOI: 10.11118/actaun200755050037

The yield of sugar beet is directly affected by LAI (leaf area index) and values of LAD (leaf area duration). The integral leaf area plays, except for other factors, an important role during the damage or reduction of leaf apparatus. There are many sources of leaf damage: natural disasters (hailstorm), diseases, pests (including game browsing) etc. The intensity of the root production and quality differs in relation to the growth stage of the damage plant. The aim of this study was to evaluate the extent of losses in the root yield and the quality of sugar beet upon gradual reduction of the leaf area. Two diploid varieties Monza and Compact were used in the small-plot trials conducted in years 2004 to 2006 (in the experimental station ®abèice - maize production region, zone K2, average altitude 184 m, soil type was classified as gley fluvisoil, soil is medium heavy to heavy, clay-loam to loam type). The leaf area was manually reduced by 25% and 50% at BBCH 18-19 growth phase (8-9 leaves unfolded). The results were statistically evaluated by analysis of variance and testing by Tukey test (at the significance level α = 5%). Reduction of the leaf area was reflected on the decrease of the root yield by 1 to 10% depending on the year of harvest. In addition, the stressful state of the plants after defoliation resulted in the decrease of the yield of polarization sugar per hectare, namely by 0.45 to 1.66 t.ha-1. In 2005, the leaf area reduction caused a rise of the α-amino nitrogen content. The rise in the potassium and sodium cations content caused by the leaf area reduction also increased the sugar content in the treacle (by 0.1 to 0.16%). The increasing leaf area reduction lead to decreasing of yield of polarization sugar. However, this descent was statistically significant in harvest year 2006 only.

Stanovení vìtrné eroze v pùsobnosti vìtrolamù

Jana Dufková

Acta Univ. Agric. Silvic. Mendelianae Brun. 2007, 55(5), 65-70 | DOI: 10.11118/actaun200755050065

The influence of shelterbelts on the erodibility of soil by wind was studied at three chosen shelterbelts of Southern Moravia, Czech Republic - near the shelterbelts in the cadastral areas of Dolní Dunajovice, Micmanice and Suchá Loz. Ambulatory measurements of wind velocity as so as soil sampling for soil humidity analyses, non-erodible and clay particles analyses were done during the year of 2006. Subsequently, real erodibility of soil by wind was determined at these three areas. Results of the measurements and calculations verify positive effect of shelterbelts consisted in wind velocity decreasing (at about 78% in average), soil humidity increasing (at about 102% in average) and soil resistance increasing (at about 70% in average) at the leeward side of the shelterbelts.

VLIV PLEMENE A RÙZNÝCH KØÍ®ENCÙ JEHÒAT BERÁNKÙ NA JAKOST MASA

Jan Kuchtík, Franti¹ek Horák

Acta Univ. Agric. Silvic. Mendelianae Brun. 2007, 55(4), 37-42 | DOI: 10.11118/actaun200755040037

Effect of breed (German Long-wooled breed, GL, n = 6) and different crossbreeds of lambs males of breeds GL, Merino (M) and Oxford Down (OD) on meat quality was evaluated on the basis of laboratory analyses of muscle of right rack (musculus triceps brachii). Following crossbreeds of lambs were evaluated: OD 50 M 25 GL (n = 6), GL 50 OD (n = 6), OD 75 GL (n = 6) and GL 75 OD (n = 6). Breed and crossbreeds had a highly significant effect (P ≤ 0.01) on contents of intramuscular fat (IMF) and ash. The factor of breed and crossbreeds had also a highly significant effect (P ≤ 0.01) on water holding capacity and reflectance and a significant effect (P ≤ 0.05) on pH of meat in the period of 24 hours after slaughter (pH 24). On the other hand the factor of breed and different crossbreeds had not significant effect on contents of dry matter (DM), protein (P), myoglobin, hydroxyproline, collagen, elastin and connective tissue. This factor had not also significant effect on energy value in the original matter. The highest values of DM (23.60 %) and IMF (3.56 %) were found in OD 50 M 25 GL. The highest values of ash (1.05 %) were foud in GL 100 and OD 75 GL. The highest value of connective tissue (2.23 mg in 100 g of muscle) was found in OD 50 M 25 GL. On the other hand its lowest content (1.86 mg in 100 g of muscle) was found in OD 75 GL.

STANOVENÍ OBSAHOVÝCH SLO®EK KOZÍHO MLÉKA POMOCÍ FT NIR SPEKTROMETRIE

Kvìtoslava ©ustová, Jan Kuchtík

Acta Univ. Agric. Silvic. Mendelianae Brun. 2007, 55(4), 103-110 | DOI: 10.11118/actaun200755040103

Our work deals with a possibility of determining basic composition (fat, true protein, casein, lactose and somatic cells) of goat's milk Fourier transform near-infrared spectroscopy (FT NIR). Samples of milk were warmed to 40 °C, agitated, cooled to 20 °C, transferred to Petri dishes and analysed by reference methods and by FT NIR in reflectance mode. The measured area was spaced by a metallic mirror. Statistically significant differences between the reference values and the calculated values of NIR were not found (p = 0.05). Very high correlation coefficients were determined for goat's milk: fat 0.907, protein 0.989, casein 0.890 and lactose 0.981. The study showed that NIRS method, when samples of milk are measured on Petri dishes, is a useful technique for the prediction of fat, true protein, casein and lactose in goat's milk. Results of calibration for somatic cells are not accurate (correlation coefficients of calibration 0,885 and correlation coefficients of validation 0.566).

Implementace standardù v eLearningových systémech

Roman Malo

Acta Univ. Agric. Silvic. Mendelianae Brun. 2007, 55(3), 161-170 | DOI: 10.11118/actaun200755030161

Nowadays, eLearning standards' support within eLearning systems is much discussed problem. In this problem domain especially the reference model SCORM must be considered. This de-facto standard is a package of common standards and specifications used for the standardization of eLearning activities as eLearning content preparation, using e-course, communication etc.
Implementation of standards itself is a process with great difficulty and time requests. Interesting and considerable approach to this problem is dividing all the process into several standalone and isolated steps focused on the individual segments of standards. This concept, in the paper described as 4-tier model of eLearning standards' implementation, principally based upon the SCORM model enables sequential implementation of support for standards of eLearning metadata, eLearning content and also communication and navigation in e-courses. This possibility leads to portability and independence of result e-content. Discuss concept is a framework for standardization within eLearning subsystem of University Information System at Mendel University in Brno.

Alternativy chromátování v protikorozní ochranì galvanicky vylouèených zinkových povlakù

Petr Verner, Vlastimil Chrást, Karel Krahula, Martin Zmrzlý, Marian Èeròanský, Jana Houdková, Vladimír Vorlíèek

Acta Univ. Agric. Silvic. Mendelianae Brun. 2006, 54(1), 135-144 | DOI: 10.11118/actaun200654010135

Surface treatment of zinc galvanized steel is carried out usually using chromate based baths. These baths are used for improvement of the corrosion resistance and enhancement of the chemical adhesion of organic coatings. Anticorrosive effects of the chromium conversion coatings were not completely exceeded yet by another kind of passivation. Toxicity of CrVI is a basic problem of chromate conversion coats. This paper presents the main results and conclusions of experimental study on zinc conversion layers based on vanadates, using a good CrVI bath as reference. Anticorrosive mechanisms were compared by the corrosion tests in saline cabinet. Inhibition effects were characterized by scanning electron microscopy, by X-ray dispersive spectrometry (EDS) associated X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy.

VHODNOST TRITIKALE K VÝROBÌ BIOETHANOLU PØI POU®ITÍ TECHNICKÝCH ENZYMÙ

Jindøi¹ka Kuèerová

Acta Univ. Agric. Silvic. Mendelianae Brun. 2006, 54(4), 33-38 | DOI: 10.11118/actaun200654040033

The aim of this contribution is to be able to used triticale in distilling industry. Four triticale varieties were grown during 2003-2005. Trials were situated in four different locations of the Czech Republic - Staòkov, Hradec nad Svitavou Krásné údolí and Libìjovice. There were used varieties Kolor, Presto, Modus and Disko. The alcoholic yield, protein content and starch content were determined. The technical enzymes Termamyl SC and SAN Extra L. were used into laboratory fermenting tests for saccharification starch. Reached alcoholic yields move between 37-46 la. The highest alcoholic yield (average three years and four locations) was estimated by variety Modus (41.19 la/100 kg. in dry matter), the lowest variety Kolor (40.08 la/100 kg in dry matter). The location Hradec n/Svitavou (41.68 la) and Krásné Údolí were favourable, the year 2005 (41.48 la) was the most positive.
The highest starch content is into positive correlation with alcoholic yield (r = 0.396) and negative with protein content (r = -0.327). The results were pointed out that triticale makes it suitable for in the distilling industry.

Statistické zhodnocení aberací èernozemí na území Moravy pøi komplexním prùzkumu pùd

Vítìzslav Vlèek, Eduard Pokorný

Acta Univ. Agric. Silvic. Mendelianae Brun. 2006, 54(2), 181-192 | DOI: 10.11118/actaun200654020181

In this paper, an attempt at measure formulation of aberation in the set of results of soil analyses observed on chernozems within Soil science is presented. The statistical evaluation was realized based on the report results from separate districts. The chernozem (regardless of subtype) were chosen as suitable for statistical evaluation. The analysis of one character was calculated for the set of results in topsoil (0-30 cm) and subsoil (30-60 cm). The comparison of average content in topsoil and subsoil was made by t-test. The significant difference is shown in content of humus (topsoil 2.61% and subsoil 1.86%), phosphorus (topsoil 8.31 mg/100 g, subsoil 4.75 mg/100 g) and kalium (topsoil 16.28 mg/100 g and subsoil 9.96 mg/100 g). There is no significant difference in other characters such as content of particles under 0,01 mm (topsoil 40.16% and subsoil 42.67%), exchange reaction (topsoil 7.03 and subsoil 7.00) and CEC - cation exchange kapacity (topsoil 23.74 mmol/100 g and subsoil 23.50 mmol/100 g). With respect to chernozems character it can be deduced, that in most of not anthropically influenced samples from mollic horizon the similar features were observed in both monitored depths. This presumption is supported also by observed differencies: humus content in topsoil was distinctly increased by addition of organic substances in organic fertilisers and by cultivation of perennial forage crops. The aberation was not observed in soil reaction. This fact could be interpreted by suppressor soil ability. Similarly, no aberation was documented in CEC. In view of quality/health of soils it is positive detection because both: exchange reaction and CEC are classified in basic soil characters. The maximal aberation was observed in phosphorous content in topsoil (with log-normal (extreme) distribution of results) and, somewhat less, in kalium content. Both characters are classified in most anthropically affected due to the addition of both components in fertilisers. Similar situation can be monitored also in the influence of humus content.

Vyu¾ití mokøadních rostlin k odvodnìní stabilizovaných èistírenských kalù

Jiøí ©álek

Acta Univ. Agric. Silvic. Mendelianae Brun. 2006, 54(2), 107-116 | DOI: 10.11118/actaun200654020107

The operators of little rural wastewater treatment plants have been interested in economic exploitation of sewage sludge in local conditions. The chance is searching simply and natural ways of processing and exploitation stabilized sewage sludge in agriculture. Manure substrate have been obtained by composting waterless sewage sludge including rest plant biomass after closing 6-8 years period of filling liquid sewage sludge to the basin. Main attention was focused on exploitation of swamp plants for dewatering liquid sewage sludge and determination of influence sewage sludge on plants, intensity and course of evapotranspiration and design and setting of drying beds. On the base of determined ability of swamp plants evapotranspiration were edited suggestion solutions of design and operation sludge bed facilities in the conditions of small rural wastewater treatment plant.

VLIV PØÍDAVKU SORBENTÙ NA KVALITU SILÁ®Í Z PIVOVARSKÉHO MLÁTA

Petr Dole¾al, Ladislav Zeman, Jan Dole¾al, Václav Pyrochta, Petr Mare¹, Franti¹ek Lád

Acta Univ. Agric. Silvic. Mendelianae Brun. 2006, 54(1), 15-22 | DOI: 10.11118/actaun200654010015

In the experiment was the effect of absorbens supplementation on the fermentation quality of brewers' grains silage by comparing with the untreated control. As effective substance of experimental groups were barleygroats and malt sprouts. The addition of malt sprouts "B" and barleygroats "C" in our experiment conditions increased statistically significantly (P

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