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The aim of this publication is to design a procedure for the synthesis of an IDT (interdigital transducer) with diluted electrodes. The paper deals with the surface acoustic waves (SAW) and the theory of synthesis of the asymmetrical delay line with the interdigital transducer with diluted electrodes. The authors developed a theory, design, and implementation of the proposed design. They also measured signals. The authors analysed acoustoelectronic components with SAW: PLF 13, PLR 40, delay line with PAV 44 PLO. The presented applications have a potential practical use. [ABSTRACT FROM AUTHOR]

The paper deals with the issue of constructing delay lines on the basis of surface acoustic waves and their application to single-mode oscillators. As a result of a theoretical analysis concrete delay lines are proposed. In the contribution, there is presented a theory of designing a symmetrical mismatched and matched delay line for a single-mode oscillator of electrical signals on the basis of which there were designed and fabricated acousticelectronic components for sensors of non-electrical quantities. From the experimental results it can be stated that all of six designed and fabricated delay lines can be effectively used in the construction of single-mode oscillators. [ABSTRACT FROM AUTHOR]

The aim of this study was to determined nutritive value of five hybrids varying in maturity sown to plots of experimental site located in southern Slovakia. Nutrient contents and digestibility parameters were obtained from samples of herbage or silages to estimate net energy of lactation (NEL) contents and milk yield (MY) potential based on in vivo digestibility of organic matter (DOM), pepsin-cellulase in vitro digestibility of OM (IVOMD) using Ankom DaisyII Incubator (Ankom Technology Corp., NY, USA), cellulase digestibility of OM (CDOMD), neutral detergent fiber (CDNDF) or in vitro digestible non starch carbohydrates (IVDNSC). Genotype effect accounted for differences in carbohydrates content and crude protein (CP). Linear regression models increased coefficient of determination (R²) when CDOMD and IVOMD were included to predict in vivo apparent digestibility NDF (NDFD) but RMSE were higher compared to DOM. Structural carbohydrate contents had mostly precise estimates but limited R² as the predictors of DOM, NDFD and NEL in combination with in vitro digestibility determinants. There was negative relationship of IVOMD and DOM (r = - 0.72; p < 0.01) but positive as it comes to CDOMD (r = 0.81; p < 0.01). Equations based on CDOMD (E7), IVDNSC and CP (E8) and CDNDF and Starch (E9) were selected to predict NEL. Residuals of NEL (observed -- predicted) ranged from -0.57 to 0.41 MJ/kg. Mid-late hybrids had higher MY kg/ha and MY kg/Mgthan early (FAO 340). E7 and E9 were sensitive to ADL content while E8 favored hybrids rich in Starch. [ABSTRACT FROM AUTHOR]

Recent experiments have demonstrated that a fundamental mechanism of the electrospinning process is the rapid whipping of an electrically charged liquid jet. This article focuses on the mathematical modeling of such a whipping, also called a bending, instability of the electrically charged liquid jet, which is created from a polymer solution by electrospinning. The ideal rectilinear segment of the electrically charged jet, the so-called “viscoelastic dumbbell”, is a key attribute of the mathematical model presented herein. We have formulated governing equations which can be used to describe the physical properties and dynamics of this segment in a three-dimensional Cartesian coordinate system. We developed a multi-threaded computer application that allows us to simulate the electrospinning process. This application is the algorithmization of a numerical discretization. Using three-dimensional computer graphics we are able to visualize the results of the computer simulations of paths of the jet as well as the depositions of electrospun nanofiber. These theoretical results are in agreement with previously published laboratory experiments. [ABSTRACT FROM AUTHOR]

Abstract: This article focuses on the analysis of electrostatic field generated by a special collector consisting of two parallel cylindrical conductors used for electrospinning. Computed values of critical electrical potential obtained by an analytical model are compared with measurements. Here we show that the gap distance between the special collector and a spinning electrode, i.e., a syringe needle, has not substantial effect on the critical potential if the special collector distance from the syringe needle is higher than the gap distance between cylindrical conductors. The presented model is a good analytical approximation of electric field created by the used special collector. [Copyright &y& Elsevier]

The paper deals with possibilities of use of television technique in diagnostics of aerial systems of radio transmitters. Graphically presented: heating characteristic of the junction at the transmitter power of 60 % (slack and polluted junction); relationship between temperature of connection (feeder -- line, capacitor frame) spacing collar and power; relationship between temperature rise amount of connection and feeder line upon power; thermograph of the junction feeder line -- spacing collar, capacity frame; thermograph of the junction feeder line -- spacing collar. [ABSTRACT FROM AUTHOR]

The aim of the experiment was to determine the amino acid content in 3 grape varieties by-products (bunch, pomace, stem) from Austria (AT) and Slovakia (SK). In total, 54 samples from 3 varieties Zweigelt (ZG), Pinot Blanc (PB) and Green Veltliner (GV) white skinned from 6 different locations (Nitra and Vienna wine region) of Vitis vinifera sp. were analysed. In each variety the amino acids composition was determined for the whole grape (bunch) and by-products of wine industry (pomace, stems). Samples of grape by-products were freeze dried, homogenized and analysed for amino acids concentration using amino acid analyzer AAA 400 (Ingos, Prague). Descriptive statistics (means, standard error of mean, minimum maximum), differences between varieties (Tukey test, p < 0.05) using One-way ANOVA and differences between the countries with independent samples T-test (p < 0.05) by IBM SPSS v. 20.0 were generated. After the amino acid analysis in grape bunch, pomace and stem in general the highest content of glutamic and aspartic acid was found. However, the grape pomace amino acid content is highly variable and statistically different between the varieties and countries. In contrary, lower variability in amino acids content between the varieties was found in grape stem. However, similar pattern in amino acids with the lowest content between the countries and varieties in grape by-products was observed. Finally, low content of Cysteine, Methionine, Histidine and Proline was found. [ABSTRACT FROM AUTHOR]

The main goal of this study was to evaluate the health condition of dairy cows in relationship to milk production and milk composition using continuous monitoring boluses. In total, seven Holstein cows had boluses implemented for monitoring rumen pH and temperature every 15 min with an accuracy of ± 0.1 pH/°C. Milk production test day records were noted by Breeding Services of Slovakia, s.e. (state-owned enterprise) 5 × per each cow with a bolus over 27 weeks of lactation. Dairy cows were divided into three groups according to their mean daily pH. After that, the test day records with the selected group were paired. Only two cows had pH values within the normal pH intervals during the control days. Consequently, there was found to be a 6.8% (P < 0.05) decrease in daily milk production in cows with lowered pH compared to cows with normal pH. Furthermore, there was found to be a 14.08% (P < 0.05) decrease in daily milk production in cows with an increased pH compared to cows with normal pH. Narrower fat to protein ratio and lactose content was found in cows with decreased and increased ruminal pH. The lowest milk fat concentration (P < 0.05) but the highest somatic cell count and urea content were determined in cows with decreased pH. These results show that continuous monitoring of rumen environment is a suitable method for nutrition and health management in dairy herds and allows the nutritionist to make nutritional interventions for pH stabilization within normal range in order to keep good milk production and high milk quality. [ABSTRACT FROM AUTHOR]

The performance of ruminants is affected mainly by the rumen bacterial community. The composition and properties of the rumen bacterial community depend largely on the diet components that are fed to the ruminant. The aim of this study was to determine the effect of grape pomace intake on the rumen bacterial community of sheep. Four different diets, two of which contained dried grape pomace (DGP), were used in this study. Rumen fluid samples from 12 wethers were used for 16S rRNA gene sequencing and subsequent bacterial identification. At the phylum level, Bacteroidetes and Firmicutes; at the family level, Prevotellaceae and Porphyromonadaeceae; and at the genera level, Prevotella and Verrucomicrobia_Subdivision5_genera_incertae_sedis were the most common regardless of the diet the animals were fed. After the addition of DGP to the diet, the relative abundance of Methanobrevibacter, Butytirivibrio, Fretibacterium, and Verrucomicrobia _Subdivision3 _genera_incertae_sedis significantly increased, whereas that of Succiniclasticum and Selenomonas significantly decreased. The upregulated pathway of methanogenesis from H2 and CO2 was supported by a significant increase in Methanobacteriaceae after the diet was supplemented with DGP. The rumen bacterial community diversity indices (Richness and Shannon) were significantly affected by diet composition as well as by the change of housing location. The addition of DGP into the wethers' diet increased the richness of the rumen bacterial community, which is good for maintaining rumen bacterial homeostasis. No adverse effect of the addition of DPG on the rumen bacterial community was noted. [ABSTRACT FROM AUTHOR]

The aim of this study was to analyse the effect of supplementary feeding of DHA (Docosahexaenoic Acid) rich algae product (Algae STM Alltech Inc.) on production of milk, fat and protein as well as on reproduction of high yielding Holstein dairy herd. Field trial was set up on Top 10 dairy farm in western part of Slovakia, under commercial conditions. The data of high yielding dairy cows, separated in two groups of 30 (control) and 29 (trial) animals, were recorded for period of 3 subsequent months from October to December 2015. Animals were fed once a day Total Mixed Ration based diet with different feed mixture composition in trial group (+100 g Algae STM Alltech Inc. per cow and day). Performance data were collected in accordance with official milk recording system of Breeding Services of Slovak Republic s. e. and milk samples were collected once per month according to the A4 standard methodology. The control group showed higher level of milk production compared to trial. Our study indicated that the feeding of algae caused milk fat depression and generally lower protein content in milk. Significant impact of algae feeding was found also for the level of urea in milk. In addition, the supplementary feeding of DHA may represent effective strategy to increase the percentage of pregnancies per inseminations in lactating dairy cows. [ABSTRACT FROM AUTHOR]

In our study the presence of bacteria, yeast, and microscopic fungi was evaluated. Three forms of corn silage were made including silage without additive, silage with microbial additive (lactic acid bacteria), and silage with nutritional additive (urea). Silage additives were applied to the matter within the recommended dosage, then the matter was ensiled into plastic bags and stored at a constant temperature. After 5.5 months of storage, average samples for microbial and mycotoxins analysis were taken. From microbiological points, the plate count agar method for enumeration of total count of bacteria, lactic acid bacteria, enterococci, yeasts, and microscopic fungi and mass spectrometry for microbiota identification were used. In total, 43 species of bacteria and yeasts and 6 genera of microscopic fungi were identified from all samples of corn silages. The most isolated species were Lentilactobacillus buchneri and Kazachstania exigua from bacteria resp. yeasts and Aspergillus and Penicillium from microscopic fungi. Mycotoxins were determined by HPLC-MS/MS and divided into two groups as regulated and emerging. In the corn silages only Fusarium mycotoxins were observed. All corn silages, regardless of the addition of the additive, were the highest in nivalenol content. Deoxynivalenol and beauvericin with the highest concentrations were present in silage with urea. Although the mycotoxins content of the variants changed, these changes were not statistically significant. In general, addition of lactic acid bacteria Lentilactobacillus buchneri and Lacticaseibacillus casei and urea as silage additives affect the microbial diversity; however, the hygienic quality of whole crop corn silage was not negatively changed. [ABSTRACT FROM AUTHOR]

The aim of this study was to analyse the effects of different daily intakes of rapeseed bee pollen on the growth and biochemical blood serum indicators in male and female rats. A total of 40 clinically healthy male and female Wistar rats were randomly divided into four groups. In the control group (C) rats were fed a standard complete diet; in the experimental groups standard diets were supplemented with different doses of bee pollen. Treatment group T1 was given standard diet with the addition of bee pollen at a 0.3% concentration; in group T2 the addition was 0.5%; and in group T3 it was 0.75%. The experimental period lasted for 90 days. A significant effect (P < 0.05) of bee pollen on the body weight gain and feed conversion ratio of female rats was found. Significantly (P < 0.05) higher cholesterol concentration in blood serum of male rats was found in the groups with bee pollen addition (groups T2 and T3) compared to the control group. Lower triglyceride serum content in all female experimental groups (T1 and T3) was observed in comparison to the control. Higher serum cholesterol content in the experimental female rats was detected; significant differences were analysed in groups T1 and T3 compared to the control female group. Rapeseed bee pollen at concentrations of 0.5 and 0.75% positively affected the body weight gain of female rats, however, with higher feed consumption (P < 0.05). Rapeseed bee pollen reduced the triglycerides serum content in female rats and increased the cholesterol serum content in male and female rats (P < 0.05). [ABSTRACT FROM AUTHOR]

Simple Summary: The introduction of alternative feedstuff such as grape pomace into the diets of dry cows could decrease the cereal needs in ruminant feeding systems and could modify the composition of colostrum. Grape pomace is a by-product of the wine industry. It contains polyphenols and fatty acids, which have the potential to improve the animal product quality. The nutritional quality of colostrum and the quality of colostral fat is affected by dry cow nutrition in the late stages of pregnancy. This study determined the potential of grape pomace feeding to increase colostral protein, which, according to the literature, is connected with the concentration of immunoglobulin G, better passive immunisation, and the health of calves. The addition of grape pomace was determined to have no effect on colostral nutrient and fatty acid concentrations. Thus, grape pomace can be used as a nutrient source for dry cows. The utilisation of different by-products from the food industry as nutrient sources for farm animals is both possible and beneficial. Grape pomace is a by-product that contains polyphenols and fatty acids, both of which have the potential to improve the nutritional quality of cow colostrum. This study aimed to explore how the addition of grape pomace to the diet of dry cows affects the concentration of nutrients and fatty acids of colostrum. Sixteen Slovak spotted cows in late pregnancy were used in this study. From the seventh day before expected calving to the day of calving, cows in the grape pomace group received a diet supplemented with dried grape pomace, at 0.116 kg/cow/day. Colostrum samples were analysed for basal nutrients and fatty acid concentrations. Between the control and experimental groups, the nutrient and fatty acid concentrations of all the colostrum samples did not show significant differences. The nutrient levels in the colostrum from both groups of cows were typical, as related to the time from calving. The addition of the grape pomace into the diet of dry cows had no effect on nutrient concentrations and the fatty acid composition of the colostrum. The somatic cell score of the colostrum sampled at the 12th hour after calving (4.2 versus 2.6) was positively affected by grape pomace addition. The results of this study revealed that grape pomace (fed in an amount of 0.116 kg/cow/day) had no positive or negative effect on the base nutrients and fatty acids of cow colostrum, and, therefore, grape pomace can be used as a nutrient source for dry cows in small amounts. [ABSTRACT FROM AUTHOR]

The aim of the study was to analyse the fatty acid profile of wild boar (Sus scrofa) meat. The samples were obtained from the mountain Tríbeč (southwest part of the Slovak Republic). A total of 36 samples in 3 age categories of meat were analysed. The effect of age on the intramuscular (IMF) fat content was analysed. The highest (P < 0.05) IMF content was found in the samples from the youngest animals (18.07%), the lowest (P < 0.05) in the sub-adult animals. Significant (P < 0.05) differences were found in palmitic acid (C16:0). Significant decrease of heptadecanoic acid (C17:0) as an effect of age was analysed in the samples. Of the important fatty acids, the most abundant in all age categories of wild boar were oleic (C18:1 cis 9), palmitic (C16:0), and linolelaidic acid (C18:2 cis n6). Differences in the content of mentioned acids were significant (P < 0.05). In a-linolenic and γ-linoleic acids, non-significant (P > 0.05) differences were detected. Significant differences (P < 0.05) between age categories were found in cis-11-eicosenoic (C20:1 n9) and cis-11,14-eicosadienoic acids (C20:2 n6). Significant differences (P < 0.05) were found in PUFA (polyunsaturated fatty acids), MUFA (monounsaturated fatty acids), and SFA (saturated fatty acids) concentrations. The highest PUFA content was typical for the samples from the oldest animals, MUFA from the sub-adults, and SFA from the youngest wild boar. More significant results were observed in the normalized data with the factor component scores. The wild boar fatty acid profile is significantly affected by age. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the effect of pumpkin and flaxseed oils on the fatty acid profile and nutrient changes in table eggs. At 38 weeks of age, Lohmann Brown Lite hens were divided into three groups depending up the diet. The birds were housed in individual cages (6 hens per cage) with a space allowance of 943.2 cm2 per hen, and given diet standard complete feed mixture for laying hens. Hens from experimental groups were fed with complete feed mixtures supplemented by pumpkin (group E1) or flaxseed (group E2) oils at a dosage of 3%. The experiment lasted 52 days. In the last week of the trial, the eggs were collected for chemical analysis. Twelve eggs from each dietary treatment were randomly selected and analysed. Significant differences between control and group E1 in the content of crude protein (P < 0.05), between both experimental groups (E1 and E2) in the content of ash (P < 0.01) in yolk, and between control and the experimental groups in the content of dry matter (P < 0.05) in albumen were detected. Significant (P < 0.01) differences were found in contents of myristic, palmitic, heptadecanoic, oleic, linoleic, and cis-11,14-eicosadienoic acids between control and experimental groups E1 and E2. Compared to control, higher (P < 0.01) concentrations of monounsaturated fatty acids, lower concentrations of saturated fatty acids and also lower contents of polyunsaturated fatty acids in the experimental groups were observed. The supplementation of flaxseed oil had a positive effect on the content of n-3 a-linolenic acid. [ABSTRACT FROM AUTHOR]

The aim of the study was to analyze the effect of different intakes of macroelements from feed on the mineral blood profile of sport horses. In the experiment which lasted for 12 months (6 months for each of the two periods), 14 sport horses with 2 types of feed rations were monitored. The blood was collected at the beginning of the experiment and every 2 months (three blood collections for each period). Feed rations had a negative effect on Ca (3.40 mmol⋅l-1 and 3.32 mmol⋅l-1) and K (3.2 mmol⋅l-1 and 2.98 mmol⋅l-1) concentrations in equine serum obtained from the second and third blood collection, respectively. Concentration of P (1.28 mmol⋅l-1 and 1.20 mmol⋅l-1) in equine serum obtained from the second and third blood collection, respectively, was higher (P < 0.05) compared to the first blood collection. Concentrations of Mg and Na were in reference intervals. In the 2nd period of experiment, feed rations were adjusted based on individual requirements of the monitored horses; the proportion of the mineral ingredient in the feed rations was lowered. More balanced concentrations of Ca, Mg, Na and K were detected in equine blood serum as a result of lower intake of the minerals from feed; the concentration of P was, except for one case, higher than in the 1st period. We observed a positive effect of individual ration compositions based on the results of blood mineral profile. The study describes for the first time the effect of a high and adequate long-term intake of macroelements on their concentrations in sport horses' blood serum. [ABSTRACT FROM AUTHOR]

Contamination by microscopic fungi and mycotoxins in different bee pollen samples, which were stored under three different ways of storing as freezing, drying and UV radiation, was investigated. During spring 2009, 45 samples of bee-collected pollen were gathered from beekeepers who placed their bee colonies on monocultures of sunflower, rape and poppy fields within their flying distance. Bee pollen was collected from bees' legs by special devices placed at the entrance to hives. Samples were examined for the concentration and identification of microscopic fungi able to grow on Malt and Czapek-Dox agar and mycotoxins content [deoxynivalenol (DON), T-2 toxin (T-2), zearalenone (ZON) and total aflatoxins (AFL), fumonisins (FUM), ochratoxins (OTA)] by direct competitive enzyme-linked immunosorbent assays (ELISA). The total number of microscopic fungi in this study ranged from 2.98 ± 0.02 in frozen sunflower bee pollen to 4.06 ± 0.10 log cfu.g-1 in sunflower bee pollen after UV radiation. In this study, 449 isolates belonging to 21 fungal species representing 9 genera were found in 45 samples of bee pollen. The total isolates were detected in frozen poppy pollen 29, rape pollen 40, sunflower pollen 80, in dried poppy pollen 12, rape pollen 36, sunflower 78, in poppy pollen after UV radiation treatment 54, rape 59 and sunflower 58. The most frequent isolates of microscopic fungi found in bee pollen samples of all prevalent species were Mucor mucedo (49 isolates), Alternaria alternata (40 isolates), Mucor hiemalis (40 isolates), Aspergillus fumigatus (33 isolates) and Cladosporium cladosporioides (31 isolates). The most frequently found isolates were detected in sunflower bee pollen frozen (80 isolates) and the lowest number of isolates was observed in poppy bee pollen dried (12 isolates). The most prevalent mycotoxin of poppy bee pollen was ZON (361.55 ± 0.26 μg.kg-1), in rape bee pollen T-2 toxin (265.40 ± 0.18 μg.kg-1) and in sunflower bee pollen T-2 toxin (364.72 ± 0.13 μg.kg-1) in all cases in frozen samples. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the effect of different biological and biochemical additives on the final nutritive quality, fermentation process and concentration of mycotoxins of ensiled high moisture crimped corn. We created four variants for the experiment: control (UC), A1, and A2 (biological stimulators with the active principle of lactic acid bacteria) and variant B (combined additives with the active principle of lactic acid bacteria, benzoate sodium and active enzymatic complex of cellulases). After 6 months of storage in laboratory conditions, we determined in experimental silages the content of dry matter ranging from 608.9 to 613 g·kg-1. The significantly lower content of crude fibre was detected in silages with additives. In silages ensiled with additives we detected the highest content of nitrogen-free extract in variant B (834.3 g·kg-1 of DM, P < 0.05). A similar effect was determined also in the content of starch; significant differences were detected in variants A1 and B (P < 0.05) compared to the control variant. We detected a significantly (P < 0.05) higher content of total sugars in trial silages; the highest content was in variant A2 (6.1 g·kg-1 of DM). In the trial variants we determined significantly the lowest content of acetic acid in variant B (2.82 g·kg-1 of DM). In case of butyric acid, whose content in the control variant was 0.22 g·kg-1 of DM, we detected the lowest content in variant A1 conserved with homo- and heterofermentative species of lactic acid bacteria. The lowest content of ammonia was determined in silages of variant B (0.074 g·kg-1 of DM). We found lower concentrations of DON and FUM (P > 0.05) after the application of biological and biochemical silage additives. In concentration of T-2 toxin we detected a significantly (P < 0.05) lower value in variant A1. In concentration of AFL we found significant differences between variants A1 and B, as well as in concentration of OT between untreated control variant (UC) and variants conserved by additives. Application of silage additives influenced the nutritive and hygienic quality of the conserved fodders. [ABSTRACT FROM AUTHOR]

Simple Summary: Looking for non-antibiotic substances that can enhance health by improving the gastrointestinal microbiome of animals is an ongoing task. Among other compounds, medium-chain fatty acids, such as lauric acid, can exert positive effects. Coconut oil is a rich source of lauric acid, and therefore, the aim of this study was to describe the effect of adding coconut oil to the feed of growing pigs on intestinal microbiome diversity and bacterial abundance. Rectal swab samples were analyzed to assess the intestinal microbiomes of pigs. Typically, growing pigs are characterized by continuously changing bacterial communities as a result of aging. However, a significant effect of coconut oil treatment was detected in the presented study. Decreases in Corynebacterium, Pseudomonadales, and Mitsuokella and increases in Alloprevotella, Bifidobacteriales, and Lactobacilli could be attributed to the supplementation of feed with coconut oil. Coconut oil treatment did not have a significant effect on the diversity index of rectal microbiomes, but an abundant increase in probiotics such as Bifidobacterium and Lactobacillus in the gastrointestinal tract is desirable in pig breeding. From this point of view, the addition of coconut oil to the feed of pigs is a good option for improving the microbiome in their gastrointestinal tracts. Coconut oil has a high content of lauric acid, which has selective antibacterial activity. This study aimed to explore the effect of coconut oil ingestion on the gastrointestinal microbiomes of pigs. A 14-day-long feeding experiment included 19 pigs in two groups (9 on a normal diet and 10 on a diet supplemented with coconut oil). At the start and end of the experiment, a rectal swab sample was taken from each pig in both groups, and total bacterial DNA was extracted. We used 16S rRNA high-throughput amplicon sequencing to evaluate the microbiome changes during the feeding experiment. A total of 446 operational taxonomic units (OTUs) were detected in the whole sample set. Shannon's indices of bacterial diversity did not change significantly during the experiment. Changes in the bacterial community during the study period and in response to the coconut oil treatment were highly significant (p < 0.001). During the study, an increase in the abundance of Lactobacillus was detected in the group treated with coconut oil. An increase in Alloprevotella, Bifidobacteriales, and Lactobacillales and a decrease in Corynebacterium, Mitsuokella, Psychrobacter, and Pseudomonadales were attributed to the coconut oil treatment. Although the addition of coconut oil to pig feed did not affect Shannon's index of diversity, it had a positive effect on the abundance of bacterial groups that are considered to be commensal and/or probiotic. [ABSTRACT FROM AUTHOR]