Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis, 2013 (vol. 61), issue 5
Results of a phenological study of the European larch (Larix decidua Mill.) growing in a mixed stand
Emilie Bednářová, Kristýna Slovíková, Sabina Truparová, Lucie Merklová
Acta Univ. Agric. Silvic. Mendelianae Brun. 2013, 61(5), 1239-1246 | DOI: 10.11118/actaun201361051239 
This paper presents an evaluation of the onset and duration of phenological stages of the European larch (Larix decidua Mill.) growing in a mixed stand in Drahanská vrchovina highlands. It covers the period of 2007-2010 and refers to results obtained in the preceding study period of 1991-2006. In individual years of this study, beginnings and durations of individual phenological stages differed in dependence on climatic conditions. Temperature requirements of European larch regarding the onset of individual phenological stages were evaluated on the base of sums of air temperatures above 0° C and of effective air temperatures higher than +5°...
Dynamics of nitrogenous substances content in the diet of the wood mouse (Apodemus sylvaticus)
Ladislav Čepelka, Marta Heroldová, Eva Jánová, Josef Suchomel
Acta Univ. Agric. Silvic. Mendelianae Brun. 2013, 61(5), 1247-1253 | DOI: 10.11118/actaun201361051247
The representation of nitrogenous substances in the stomach content of Apodemus sylvaticus was determined using the NIRS (near-infrared spectroscopy) method. Out of the total of 247 examined stomachs, 66 were male and 181 female. Sampling of study material was conducted in 2003-2010 at three isolated forest sites in South Moravia with different habitat conditions and different type of management (old semi-natural forest with dominance of English Oak (Quercus robur); production forest with dominant Sessile Oak (Quercus petraea) and Black Locust (Robinia pseudoacacia); pheasantry with variable mixture of forest plots). The...
Energy and economic effectiveness of winter rape and winter wheat cultivation for liquid biofuel production
Tomasz K. Dobek, Marek Rynkiewicz, Jan Červinka, Jan Mareček
Acta Univ. Agric. Silvic. Mendelianae Brun. 2013, 61(5), 1255-1259 | DOI: 10.11118/actaun201361051255
Aim of this study was an analysis and assessment of the economy and energy effectiveness of winter wheat and winter rape cultivation for liquid biofuel production. The cost of production and economical effect index is more profitable in case of winter rape. Also the final balance of energy effectiveness has shown better values if the biodiesel had been produced from winter rape as compared with bioethanol from winter wheat. Calculation of the obtained products and their comparison with an energy unit has shown that the netto energy from biodiesel was positive while that from bioethanol was negative, which means that in the latter case expenditure is...
Ecology of beech regeneration in the allochthonous spruce stands - a case study
Lumír Dobrovolný, Miroslav Cháb
Acta Univ. Agric. Silvic. Mendelianae Brun. 2013, 61(5), 1261-1268 | DOI: 10.11118/actaun201361051261
We study the successional process of beech in a allochthonous spruce monocultures. In the natural regeneration of the predominatly spruce stand (area: 14.28 ha, age: 110 years) with single mother beech trees admixture the spruce regeneration occupies the most part of the study area. However, about one quarter of area is occupied relatively regular by beech regeneration. The spruce density was at all times higher than that of beech while the spruce height grow was by contrast at all times lower than that of beech. Mean distance of beech seedlings dispersion is 12.7; at a distance greater than 40 m, the density already neared zero. Density of spruce...
Determination of mixing quality in biogas plant digesters using tracer tests and computational fluid dynamics
Luděk Kamarád, Stefan Pohn, Günther Bochmann, Michael Harasek
Acta Univ. Agric. Silvic. Mendelianae Brun. 2013, 61(5), 1269-1278 | DOI: 10.11118/actaun201361051269
The total electricity demand of investigated biogas plants (BGP) makes up 7-8 % of the total electricity produced. Nearly 40 % of this energy is consumed just for mixing in digesters and the energy demand for mixing in some biogas plants can be even higher. Therefore, optimal mixing in anaerobic digesters is a basic condition for efficient plant operation and biogas production. The use of problematic substrates (e.g. grass silage or other fibrous substrates), installation of unsuitable mixing systems or inconvenient mixing intervals may lead to mixing problems. Knowledge about mixing in biogas digesters is still insufficient, so the objective of this...
Resolving browning during the establishment of explant cultures in Vicia faba L. for genetic transformation
Helena Klenotičová, Iva Smýkalová, Lenka Švábová, Miroslav Griga
Acta Univ. Agric. Silvic. Mendelianae Brun. 2013, 61(5), 1279-1288 | DOI: 10.11118/actaun201361051279
Optimisation of in vitro regeneration systems of two explant types for low-tannine cultivars of faba bean based on culturing of shoot apices and cotyledonary nodes were provided by usage of various antioxidants - ascorbic acid, citric acid, glutathione and activated charcoal. In subsequent testing, the combined effects of antioxidants with transformation co-cultivation compounds acetosyringone and L-cysteine was studied. The application of antioxidants lead to decreased callogenesis, citric acids treatments (50 mg.l-1) dramatically decreased necrotic response of explants. However, citric acid, used together with ascorbic acid completely...
The utilization of rapeseed expeller for carp (Cyprinus carpio) diets
Vladimír Kukačka, Jiří Jirásek, Radovan Kopp, Jan Mareš
Acta Univ. Agric. Silvic. Mendelianae Brun. 2013, 61(5), 1289-1295 | DOI: 10.11118/actaun201361051289
Production effectiveness of rapeseed stamping in the common carp fodder was attested in the controlled conditions of recirculation system with the absence of natural food. 4 isonitrogenous (31.5% NS) and isoenergetic (17.3 MJ GE.kg-1, resp. 13.5 MJ DE.kg-1) diet with different (35 and 40%) unmodified (URS) and technologically modified (MRS) rapeseed expeller ratio were tested. During the sixty-day feeding trial, beneficial production effect of diet with modified stamping was proved. Diet MRS fish were characterized by significantly (P < 0.05) faster length growth. In comparison with fry of MRS variant, they have reached highly...
Oils degradation in agricultural machinery
Vojtěch Kumbár, Petr Dostál
Acta Univ. Agric. Silvic. Mendelianae Brun. 2013, 61(5), 1297-1303 | DOI: 10.11118/actaun201361051297
Evaluating of oils condition in agricultural machinery is very important. With monitoring and evaluating we can prevent technical and economic losses. In this paper there were monitored the liquid lubricants taken from mobile thresher New Holland CX 860. Chemical and viscosity degradation of the lubricants were evaluated. Temperature dependence dynamic viscosity was observed in the range of temperature from -10 °C to 80 °C (for all oils). Considerable temperature dependence dynamic viscosity was found and demonstrated in case of all samples, which is in accordance with theoretical assumptions and literature data. Mathematical models were developed...
Design and verification of additional filtration for the application of ecological transmission and hydraulic fluids in tractors
Pavel Máchal, Radoslav Majdan, Zdenko Tkáč, Bohuslav Stančík, Rudolf Abrahám, Ivan Štulajter, Peter Ševčík, Milan Rášo
Acta Univ. Agric. Silvic. Mendelianae Brun. 2013, 61(5), 1305-1311 | DOI: 10.11118/actaun201361051305
This contribution presents the design and function verification of additional filtration. It is intended for the common transmission and hydraulic oil filling of tractors. The main role of this filtration concept is to ensure a high level of oil cleanness as a condition for the application of ecologic fluids in tractors. The next one is to decrease the wear of lubricated tractor components, the degradation of oil and eventually to extend the interval of oil change. The designed additional filtering is characterized by ease installation through the use of quick couplings and hoses to the external hydraulic circuit. Therefore, the filtration is suitable...
Design of a laboratory hydraulic device for testing of hydraulic pumps
Pavel Máchal, Zdenko Tkáč, Ján Kosiba, Juraj Jablonický, Ľubomír Hujo, Marián Kučera, Juraj Tulík
Acta Univ. Agric. Silvic. Mendelianae Brun. 2013, 61(5), 1313-1319 | DOI: 10.11118/actaun201361051313
The present contribution deals with solves problem of research of testing device to monitor of hydrostatic pumps durability about dynamic loading under laboratory conditions. When carrying out the design of testing device are based on load characteristics of tractor hydraulic circuit, the individual characteristics of hydraulic components and performed calculations. Load characteristics on the tractors CASE IH Magnum 310, JOHN DEERE 8100, ZETOR FORTERRA 114 41 and Fendt 926 Vario were measured. Design of a hydraulic laboratory device is based on the need for testing new types of hydraulic pumps or various types of hydraulic fluids. When creating of...
Assessment of stability of a revitalized stream T12 in Orlické Záhoří
Jana Marková, Petr Pelikán
Acta Univ. Agric. Silvic. Mendelianae Brun. 2013, 61(5), 1321-1328 | DOI: 10.11118/actaun201361051321
The aim of presented project is to execute an analysis and evaluation of stream-bed conditions for streams after revitalisation measures. Revitalisation of stream T12 in Orlické Záhoří has been comprehensive, included changes of stream line and longitudinal and transversal profile. The evaluation was so provided in two absolutely different stream-beds.The evaluation was focused on stream-bed ground and slopes stability, which were established on the base of tangential stress, scouring and nonscouring velocity and of mean velocity in vertical calculation. Then the individual methods of calculation were compared and the results were faced with actual...
Carotenoids and lycopene content in fresh and dried tomato fruits and tomato juice
Andrea Mendelová, Martina Fikselová, Ľubomír Mendel
Acta Univ. Agric. Silvic. Mendelianae Brun. 2013, 61(5), 1329-1337 | DOI: 10.11118/actaun201361051329
Important component of the tomato are carotenoid dyes, especially lycopene. The importance of lycopene in the diet of people in recent years has grown mainly for its pharmacological effects due to its ability to reduce the risk of carcinoma diseases and prevention of cardiovascular diseases. The aim of this work was to analyze the content of total carotenoids and lycopene in 8 varieties of tomato and to monitor dynamic changes after their different treatments (heating, drying). The experiment included following tomato varieties: Bambino F1, Darina F1, Diana F1, Denár, Milica F1, Orange F1, Paulína F1, Šejk F1.We found that processing of tomato...
Evaluation of airborne laser scanning data for tree parameters and terrain modelling in forest environment
Tomáš Mikita, Martin Klimánek, Miloš Cibulka
Acta Univ. Agric. Silvic. Mendelianae Brun. 2013, 61(5), 1339-1347 | DOI: 10.11118/actaun201361051339
The aim of this article is to analyse possibilities of airborne laser scanning (ALS) data utilization in forestry, especially for the purposes of terrain modelling and for forest inventory (determination of forest height, diameter breast height and volume - DBH). The accuracy of ALS data in forestry was tested on the area of 1.5 ha. On this area the topography and location of all trees as well as their heights were surveyed in detail by means of total station. Firstly, the altitudinal accuracy of ALS for the creation of digital elevation model (DEM) was evaluated, based on the comparison with relief measurement. The research also evaluated different...
The effect of temperature and loading rate on the rheology of butter
Šárka Nedomová, Jana Strnková, Jaroslav Buchar, Vladimír Sýkora
Acta Univ. Agric. Silvic. Mendelianae Brun. 2013, 61(5), 1349-1356 | DOI: 10.11118/actaun201361051349
Series of the indentation of the cone (60°) by the constant speed into blocks butter has been conducted. The indentation tests were performed at different speeds (1, 6 and 60 mm.min-1), and the corresponding force - displacement responses were fitted with an analytical solution to obtain the time-dependent constants and the instantaneous force-displacement response. Experiments have been performed on 18 different commercially available butters. A puncture test was performed to investigate the rheological properties of the food materials at 4 °C and at 19 °C. The indentation force decreases with the temperature. It increases with the loading...
Evaluation of selected reproductive parametres in gilts and loss of piglets after repopulation
Pavel Nevrkla, Marie Čechová, Zdeněk Hadaš
Acta Univ. Agric. Silvic. Mendelianae Brun. 2013, 61(5), 1357-1364 | DOI: 10.11118/actaun201361051357
The aim of this study was to evaluate selected parametres of reproduction in sows in the first litter and piglets loss from birth to weaning after repopulation in a production sow herd. Observed parametres were evaluated in two commercial programs. An experimental group consisted of 80 gilts (40 in commercial program A and 40 in commercial programm B). Gained values of the total number of piglets per litter were 16.23 ± 2.26 from gilts in the program A and 15.63 ± 2.13 from gilts in the program B. Evaluation of live-born piglets per litter showed numbers of 14.74 ± 2.09 in the program A and 14.50 ± 2.10 in the program B....
The effect of iodine and strumigens long-term foodborne intake on histometrical parameters of thyroid gland in gimmers
Zdeněk Peksa, Jan Trávníček, Roman Konečný, František Jelínek, Hana Dušová, Kateřina Volfová, Aneta Vrbová, Luboš Zábranský, Daniel Falta, Václav Pálka
Acta Univ. Agric. Silvic. Mendelianae Brun. 2013, 61(5), 1365-1369 | DOI: 10.11118/actaun201361051365
In 2010 and 2011 two experiments on gimmers of Šumava mountain sheep were performed. The first experiment was carried out on 12 animals (experimental period was 11 months); control group was fed with 3 mg I*kg-1 in dry matter per day and experimental group was fed with 5 mg I*kg-1 in dry matter per day. The second experiment lasted 10 months and it was carried out on 12 animals. Feed ration for control group contained 10 mg I*kg DM-1. Feed ration for experimental group contained 10 mg I*kg DM-1 too; moreover it included rapeseed meal and 1 g of sodium nitrate. The aim of the first experiment was focused on...
Effect of time from harvest to agglomeration process of herbaceous mass on the density and hardness of briquettes
Marek Rynkiewicz, Petr Trávníček, Petr Junga
Acta Univ. Agric. Silvic. Mendelianae Brun. 2013, 61(5), 1371-1376 | DOI: 10.11118/actaun201361051371
The study presents the results about the density and hardness of the briquettes produced from barley straw, wheat and rapeseed straw and hay. 6-month and 18-month raw materials after harvest from the fields were used to the agglomeration, stored in stacks in the field. The study showed that the briquettes produced from 6-month material characterized by a greater density in the comparison with the 18-month material. The difference was 130.28 kg.m-3 for the hay briquette, whereas the difference was 58.14 kg.m-3 in the case of rape straw briquettes. Similar results were found for the hardness. All samples of briquette used for testing...
Influence of annealing temperature of straw briquettes on their density and hardness
Marek Rynkiewicz, Petr Trávníček, Eva Krčálová, Jan Mareček
Acta Univ. Agric. Silvic. Mendelianae Brun. 2013, 61(5), 1377-1382 | DOI: 10.11118/actaun201361051377
The study evaluated the effect of annealing temperature of non-wood, herbaceous ground briquettes on their density, hardness and fracture incidence. The study showed an average density of hay briquettes at 20 °C was 1 256.99 kg.m-3, whereas at 60 °C density increased to 1 369.44 kg.m-3. The analysis showed statistically significant differences in the average densities of briquettes, depending on their temperature. Temperature of briquettes also had a statistically significant effect on their hardness. In case the temperature increases from 20 to 60 °C both longitudinal and transverse cracks were observed for all samples.
Dynamics of the cyanobacterial water bloom with focus to Microcystis and its relationship with environmental factors in Brno reservoir
Lucie Straková, Radovan Kopp, Eliška Maršálková, Blahoslav Maršálek
Acta Univ. Agric. Silvic. Mendelianae Brun. 2013, 61(5), 1383-1390 | DOI: 10.11118/actaun201361051383
Our paper brings new information about long-term changes of the phytoplankton communities in the Brno reservoir with the focus on the Microcystis abundance using the semi-monthly monitoring data covering the period 2006-2012. The main aim is to extract from this long-term data set differences in number of Microcystis cells depending on environmental factors. The development of cyanobacteria in Brno reservoir is caused by excessive phosphate loading from wastewater treatment facilities upstream and from non-point sources along the Svratka river. It focuses management effort on upstream controls of reservoir condition. High abundance in...
The economic efficiency of forest energy wood chip production in regional use - A case study
Dalibor Šafařík, Tomáš Badal
Acta Univ. Agric. Silvic. Mendelianae Brun. 2013, 61(5), 1391-1398 | DOI: 10.11118/actaun201361051391
This regional project case study deals with the limiting factors of economic efficiency in the production of forest energy wood chips. The evaluation of production efficiency made use of data obtained from the Lesy města Brna, a.s. (Forest of the City of Brno, Corp.), which were subjected to two static methods of investment evaluation: an analysis of the tipping point and determination of the limit of variable costs and a dynamic modified tipping point analysis using cash flow (i.e. cash break even analysis). The results have confirmed an established hypothesis, namely that the decisive factor in the profitability of the production of forest energy...
Occurrence of couch grass [Elytrigia repens (L.) Desv. ex Nevski] under different grassland management
Marie Štýbnarová, Pavlína Mičová, Hana Karabcová, Marie Svozilová
Acta Univ. Agric. Silvic. Mendelianae Brun. 2013, 61(5), 1399-1404 | DOI: 10.11118/actaun201361051399
The objective of this research was to investigate occurrence of common couch grass (Elytrigia repens (L.) Desv. ex Nevski) under different grassland management by means of a small-plot trial. The trial was managed during 2003-2011 with four levels of utilisation: intensive (4 cuts per year, 1st cut on 15 May), medium intensive (3 cuts per year, 1st cut on 30 May), low intensive (2 cuts per year, 1st cut on 15 June), and extensive (2 cuts per year, 1st cut on 30 June). Four rates of fertilisation were applied for each utilisation treatment: nil-fertilisation, P30K60, N90P30K60,...
Arthropod diversity (Arthropoda) on abandoned apple trees
Pavla Šťastná, Václav Psota
Acta Univ. Agric. Silvic. Mendelianae Brun. 2013, 61(5), 1405-1422 | DOI: 10.11118/actaun201361051405
In 2010 and 2011, the occurrence of arthropods on apple trees without management was monitored near the village of Velké Bílovice, South Moravia, in two selected localities (an abandoned apple tree orchard and a road apple tree alley). Arthropods in tree tops were killed using deltamehtrin applied with a fogger (Puls Fog). Each collection always contained the material from 5 trees in each site. In 2010, three collections were performed (28/4, 20/5, and 9/7), two in 2011 (11/5 and 23/6). Representatives of eleven orders were captured. Of all the orders trapped, Coleoptera was represented most frequently, the Hymenoptera and Diptera followed. In the...
Avoidance behaviour testing of Eisenia andrei in biodegradable plastic environment
Zuzana Tichá, Pavel Mach, Markéta Žáková, Monika Vítězová
Acta Univ. Agric. Silvic. Mendelianae Brun. 2013, 61(5), 1423-1429 | DOI: 10.11118/actaun201361051423
Avoidance behaviour test with the earthworms (ISO 17512-1:2008) is a rapid screening test for the evaluation of soil and the influence of pollutants and chemicals on the behaviour of earthworms. The purpose of the testing is to determine the avoidance behaviour of earthworm (in this case Eisenia andrei was used) which can be used as an organism for the composting and occur naturally in soil environment. The methodology was modified according to the needs of the avoidance behaviour testing of earthworms in biodegradable plastic environment. It is a biodegradable thermoplastic material Mater-Bi, which is produced from corn starch. Californian...
The effect of mineral fertilization on belowground plant biomass of grassland ecosystems
Ján Tomaškin, Ján Jančovič, Ľuboš Vozár, Judita Tomaškinová
Acta Univ. Agric. Silvic. Mendelianae Brun. 2013, 61(5), 1431-1440 | DOI: 10.11118/actaun201361051431
Aim of the work was to determine the effect of different doses of mineral fertilization on belowground and aboveground plant biomass production of three different types of grasslands, to state R:S ratio (root:shoot) and turnover period of belowground plant biomass of grasslands. In the contribution, we assess production of underground biomass, tillering zone and aboveground biomass on three types of grasslands - permanent grassland (PG), over-sown grassland (OSG) and temporary grassland (TG) in sub-mountain area of central Slovakia. There were applied four levels of mineral nutrition in each grassland (non-fertilized variant, var. 30 kg.ha-1P...
Verification of the occurrence of some plant species as indicators of landfill impact on the environment
Magdalena Vaverková, Dana Adamcová, František Toman
Acta Univ. Agric. Silvic. Mendelianae Brun. 2013, 61(5), 1441-1450 | DOI: 10.11118/actaun201361051441
An ecological study was conducted on landfill site in Kuchyňky, Czech Republic. Our paper focuses on verification of research into the issue of waste disposal and the possibilities of using bioindicators to assess landfill impact on the surroundings. The subject of research was surface area of the landfill and its immediate surroundings. Sampling was carried out in 2010-2012 and compared with simple floristic list prepared in 2007. Floristic composition was explored in individual segments. Species abundance was established by valuating the simple presence of the species: 1 yes, 0 no, N not identified - irrespective of population abundance. During the...
Landscape dynamics in the Brno's surrounding between 2001 and 2011
Hana Vavrouchová, František Toman
Acta Univ. Agric. Silvic. Mendelianae Brun. 2013, 61(5), 1451-1457 | DOI: 10.11118/actaun201361051451
In surroundings of the larger cities there are possible to observe one of the symptoms of today's postmodern society - suburbanized surface. A number of primary and secondary negative effects of this process are undisputed. To identify these influences in specific locality, analyze of structural and functional changes of territory are appropriate to make first. Spatial indicators are a suitable analytical tool for the synthetic evaluation of these changes. The indicators are simple and able to document the changes within land use categories in the time period, to identify just those categories with the most significant transformations and to objectify...
Changes of landscape structure and cultural values of vineyard landscape
Martina Verešová, Ján Supuka
Acta Univ. Agric. Silvic. Mendelianae Brun. 2013, 61(5), 1459-1470 | DOI: 10.11118/actaun201361051459
The aim of this paper is to assess the structural changes development of vineyard type of cultural agriculture landscape in Čajkov cadastre. In landscape space out of built up rural settlement Čajkov the vineyards create a specific landscape segment which covers 6% of the whole cadastre area. Two time development periods are compared, i.e. 1896s and 2010s, or 2011s with emphasis to land use form changes and area size changes of vineyard parcels. The result shows that vineyards represent more than 100 hundred years continuity of historical valuable cultural landscape which was not influenced by agricultural collectivisation processes within the second...
Characterisation of actinomycetes community from the heavy metals-polluted soil
Monika Vítězová
Acta Univ. Agric. Silvic. Mendelianae Brun. 2013, 61(5), 1471-1478 | DOI: 10.11118/actaun201361051471
The isolation of actinomycetes was performed from soil samples influenced by car-traffic. The acute toxicity of soil leaches was tested by the help of Microtox® bioassay testing system which uses freeze dried luminescent bacteria Photobacterium phosphoreum as the test organisms. The content of heavy metals in biomass of soil microorganisms and in whole soil samples was determinate. 115 strains of actinomycetes were isolated and their total numbers in soil samples were estimated. The acute toxicity of soil influenced the total numbers of actinomycetes. By the help of DNA-DNA reassociation procedure the generic diversity of bacteria...
Microbiological characteristics of bioaerosols at the composting plant
Monika Vítězová, Tomáš Vítěz
Acta Univ. Agric. Silvic. Mendelianae Brun. 2013, 61(5), 1479-1485 | DOI: 10.11118/actaun201361051479
The diversion of biodegradable waste from landfill is of key importance in developing a sustainable waste strategy for the next decade and beyond. The proliferation of waste treatment technologies such as mechanical biological treatment, anaerobic digestion and composting will be paramount in achieving this strategic goal. Composting plant is one of the end technology, which is widely used in waste processing of the biodegradable waste. These wastes originate from the maintenance of green areas in the cities and the municipalities and from the separatelly collected biodegradable waste from the citizens. There is also possible to process other biodegradable...
Corrosion resistance of zinc-based systems in NaCl environment
Jiří Votava
Acta Univ. Agric. Silvic. Mendelianae Brun. 2013, 61(5), 1487-1495 | DOI: 10.11118/actaun201361051487
Metal components in engineering, industry and agriculture are subjects of degradation process influenced by corrosion which result in changes of mechanical characteristics. The current trend of anticorrosion protection is aimed at inorganic metal zinc-based coatings, such as zinc dipping which can be improved by duplex protection. This paper deals with two types of corrosion protection of steel components by zinc coating, first of which is produced by hot dip galvanizing, the other by Zn-Al spray.Hot dip galvanizing was processed in working conditions; the Zn-Al coating was sprayed following the instructions of producer. It is a special aerosol...
Influence of edge radius of sintered-carbide tip on roughness of machined surface
Jiří Votava
Acta Univ. Agric. Silvic. Mendelianae Brun. 2013, 61(5), 1497-1504 | DOI: 10.11118/actaun201361051497
Increasing of cutting speed and thus increasing labour productivity is observed as a current trend in engineering production. This effort results to development of new cutting materials which are more capable to resist increased requirements on machined surface as well as operating life of the instrument. Nowadays, the most widely used materials used for cutting instruments are sintered carbides which are alloyed by other metals.The goal of this paper is to analyse change in quality of machined surface depending on the change of cutting conditions. For cutting operation, there were used a milling cutter high-speed steel 90 (HSS) and removable sintered-carbide...
Occurrence of mastitis pathogens in relation to somatic cells
Marcela Vyletělová Klimešová, Oto Hanuš, Lucie Hasoňová, Petr Roubal, Ivan Manga, Ludmila Nejeschlebová
Acta Univ. Agric. Silvic. Mendelianae Brun. 2013, 61(5), 1505-1511 | DOI: 10.11118/actaun201361051505
There were examined 161 cows from 4 farms in total. The suspect animals were selected according to viscosity test results, clinical symptoms and somatic cell count (SCC). Milk samples were examined for the presence of pathogens and for SCC. 55 mastitis pathogens were identified. The most frequently isolated species was Enterococcus faecalis (n = 20), followed by Staphylococcus aureus (n = 6) and Streptococcus uberis (n = 5). The SCC ranged from 9 to 24 204 ths.ml-1. There was positive occurrence of bacteria genus Staphylococcus and Enterococcus at lower SCC (50 ths.ml-1) and at higher SCC numbers...
Bioavailability of liquid methionine hydroxy analogue-free acid relative to DL-methionine in broilers
Jiří Zelenka, Jaroslav Heger, Vlastislav Machander, Markus Wiltafsky, Martin Lešták
Acta Univ. Agric. Silvic. Mendelianae Brun. 2013, 61(5), 1513-1520 | DOI: 10.11118/actaun201361051513
An experiment with broiler chickens was conducted to compare the relative bioavailability of liquid methionine hydroxy analogue free acid (MHA-FA) with that of DL-methionine (DLM) during fattening to 35 days of age. Ross 308 male chicks were allotted to 9 treatments, each consisting of six replicates of 140 birds/pen. Four graded levels (0.04, 0.08, 0.16, and 0.28 %) of MHA-FA or DLM products (weight/weight comparison) were added to a maize-wheat-soyabean meal basal diet deficient in sulphur amino acids. The criteria of response were body weight, feed conversion ratio, carcass yield and breast meat yield. Significant responses to graded levels of both...
Trends in temperature and precipitation in the period of 1961-2010 in Žabčice locality
Zdeněk Žalud, Jan Brotan, Petr Hlavinka, Miroslav Trnka
Acta Univ. Agric. Silvic. Mendelianae Brun. 2013, 61(5), 1521-1531 | DOI: 10.11118/actaun201361051521
The paper evaluates fifty-year series of meteorological data measured at the experimental field station of Žabčice training farm belonging to Mendel University in Brno. The evaluated temperature and precipitation data from 1961 to 2010 were divided into the normal period of 1961-1990 and the subsequent period of twenty years from 1991 to 2010. In addition to the monthly data, different parts of the year were assessed and compared. The findings of this local study carried out in the warmest and also the driest locality in the Czech Republic imply a change in the development of climate. Ten of the twelve months show higher average temperatures in the...
Latest aspects of mechanical filtration
Stanislav Koláček, Michal Černý
Acta Univ. Agric. Silvic. Mendelianae Brun. 2013, 61(5), 1535-1542 | DOI: 10.11118/actaun201361051535
The aim of this study was to describe and unify all knowledge about mechanic filtration. The first part deals with the parameters and properties of filtration. Here some important basic concepts are explained such as pressure gradient, filter life, etc. There's also a description of convenient filtration technology for coarse and fine materials, such as sand, smoke or soot. The second part primarily focuses on the real use and application of filters for liquid and gaseous media. The differences in construction between different types of filters for filtration of fuels, oils, hydraulic fluids, air and cabin filters are described. The last section is...