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A simple 1-D mathematical model for prediction of local temperatures in a layer of solid material during microwave heating (Houšová et al. 1998) and a sensitivity analysis were used to evaluate the influence of process and material parameters on vertical temperature profiles in a layer of material during heating. The results of calculations are presented in graphs and discussed. The incident microwave power and heat capacity and density of heated material are parameters with great effect on all local and average temperatures and local and average heating rates. The shape of temperature profile is influenced only to a small extent by a change in the value of applied microwave power and also in the value of heat capacity or density of heated material. The whole profiles shift to higher or lower temperature values when the incident microwave power is changing. The distribution of applied microwave power between the upper and bottom layer surface very much influences the shape of the profile and the values and position of the highest and the lowest temperature in the layer. Depth of penetration and thermal conductivity of heated material influence on the shape of temperature profiles and the temperature spread in the layer (evenness of temperature distribution). Effect of penetration depth also depends on the relation to the layer thickness - its effect increases with the increasing layer thickness. At the low values of penetration depth relative to the layer thickness, an uneven temperature profile is to be expected. Effect of thermal conductivity value on temperature profile depends on the time of heating. Because of a short time of microwave heating, the effect of this parameter on temperature distribution is smaller compared to the conventional heating methods. At the beginning of heating its influence is quite negligible. Temperature of the air surrounding the layer and intensity of heat exchange between the air and layer surface are parameters with only small local effect on temperature distribution.

Numerous data point to the fact that Czech people played an important role in the cultural development of Croatia. Professor Josip Ubl was one of the many outstanding Czech veterinarians who greatly contributed to the Croatian veterinary medicine. Prof. Josip Ubl was born on the 4th April 1844 in Chudenice, in the Plzeň district. He descended from a respectable family, which highly influenced his schooling. He finished his primary and secondary education at his birthplace. He graduated from the k. u. k. Militär-Thierartznei-Institute in Vienna in 1867. Prof. Josip Ubl first worked as an assistant lecturer and as a professor of animal husbandry and veterinary medicine at the School of Farming and Farming Crafts in Doubravice near Loštice and Mohelnice in Moravia. Later on he was appointed a teacher of veterinary medicine, animal husbandry, anatomy and zoology at the Kraljevsko gospodarsko-šumarsko učilište i ratarnica (Royal School of Farming and Forestry) in Križevci in Croatia. He was an exceptionally prolific writer and wrote seven veterinary manuals. Besides being an outstanding teacher he was also engaged in social work and was awarded for his contribution to this field of work several times. As the author of the first veterinary works in Croatian language and the creator of the Croatian veterinary terminology he has gained a prominent place in the history of Croatian veterinary medicine.

The task of applied research is not only to acquire new knowledge, through which it contributes to the development of economy, to the consumer protection or to the training of qualified experts. For state-supported veterinary research, this means striving to protect people's health against diseases transmitted from animals, food-born diseases, contamination of feed and foodstuffs by toxic xenobiotics, a reduction in food quality through the use of low-grade raw materials and an adverse effect of environmental pollution. The territory of the state must be protected against the infectious diseases and animals against the negative effects of environment and technologies which often strive irresponsibly for the highest profits without regard for the consequences. The contributions of the Veterinary Research Institute, Brno, and other Czech research facilities to increasing knowledge on cattle health and reproduction are documented by the list of 105 references of papers published in peer reviewed journals since 1992. This article is available on http://www.vri.cz/vetmed.asp and the reprints of cited references can be requested by e-mail to <vri@vri.cz>

The goal of this work was to verify the spice adulteration by the microscopic analysis. The samples of black powdered pepper and its meat product that did not have the expected spice and aromatic properties were controlled. The results of sensory and chemical investigation corresponded with microscopic findings. The suspected sample of spice and meat product with spice contained pronounced coloured parts that were not present in the usual structure of powdered pepper.

The changes in microbiological and chemical parameters during the fermentation and ripening of sheep cheese were observed. The cheese was produced from raw sheep's milk at different temperatures on the sheep farm. The following parameters were determined: total plate count, coliform count, Staphylococcus aureus count, pH value, titrimetric acidity, and the amount of lactic acid. As our results indicate, the fermentation at temperatures of between 18-22°C reduces the number of undesirable micro-organisms due to the presence of lactic acid being produced by lactic-acid bacteria. During the fermentation at lower temperatures (below 18°C) the amount of lactic acid is insufficient, and the undesirable microorganisms can survive.

Distribution of leukocyte types present in virgin bovine mammary glands was analysed in dot plots obtained by flow cytometry (FACS) of samples collected from 10 non-pregnant heifers after induction of leukocyte influx. Changes of percentage of leukocyte types during development and resolution of induced influx in comparison with blood leukocyte pattern allow identification of these cell types on FACS dot plot. The positions of mammary gland granulocyte and lymphocyte regions were identical with those of the corresponding peripheral blood cells. Two basic morphologically distinct types occupying separate regions in dot plots were observed in the population of mononuclear phagocytes (MoP): non-vacuolised monocyte-like macrophages (MoMAC) and vacuolised macrophages (MAC). Influx resolution was characterised by a marked shift of the MoMAC region towards that of MAC recognisable in dot plots by a separate region of intermediate MoP forms. The study provides a pattern of dynamics of percentages of mammary gland leukocyte types during influx development and resolution as imaged by FACS.

Two monoclonal antibodies (MAb) to the outer structural protein E2 (spike peplomeric protein) and two MAb to the inner capsid protein N of bovine coronavirus (BCV) were prepared and identified by Western blotting to be used for increasing the specificity and sensitivity of BCV detection. The MAb were checked by the haemagglutination inhibition test and immunoperoxidase tests and no cross reactivity with rotavirus was demonstrated by the immunoperoxidase test and ELISA. A mixture of all the four MAb at predetermined optimum concentrations was first used in sandwich ELISA and then, in combination with an anti‑coronavirus polyclonal antibody, for the development of a simple and rapid immunochromatographic test (ICT). The results of which can be read visually within 10 min. The inclusion of MAb into ELISA and ICT allows the detection of both intact and incomplete BCV virions. ELISA and ICT were used in the examination of a set of 74 faecal samples collected from calves suffering from diarrhoea. ELISA, used as the golden standard verified by electron microscopy, detected BCV in 15 samples (20.3%) and ICT in 16 samples. Three of the ICT‑positive samples were negative by ELISA. On the other hand, two of the 58 ICT‑negative samples were positive by ELISA. Sensitivity and specificity of ICT were 94.9% and 86.7%, respectively

The bionomics of Acarus siro was studied at 18 and 20°C and 70 and 80% R.H. on wheat germs, linseed, rapeseed and sunflowers to obtain data for optimisation of biological control of stored product mites on oilseeds. Wheat germs were used as a control substrate as they were considered optimal for development of A. siro. The development of eggs and larvae was longer than that of protonymphs and tritonymphs. Wheat germs appeared to be a better substrate for the development of mites than oilseeds. Generally, the life span of females as well as the oviposition period was shortest on wheat germs while longest on sunflower; also, at the higher temperature the female life span was shorter. The maximum number of eggs laid by a single female (356) was recorded on wheat germs at 20°C and 80% R.H. The development was significantly shorter at 20°C than at 18°C regardless of humidity. There were no significant differences between the effects of the tested oilseeds.

The bread-making quality of forty commercial winter wheat samples, grown in the western region of the CzechRepublic, and their flours (white flours with ash content of about 0.5%) prepared in a commercial mill was studied. Standard analytical methods (ash and protein content, wet gluten), amylolytic activity measurement (falling number), rheological investigation (alveograph, gluten index), sedimentation test and laboratory baking test were used for characterization of wheats and flours. In addition NIR method was used to calculate ash, wet gluten, sedimentation value and protein content. Statistically significant correlations were found practically between all tested quality parameters of wheat and corresponding flour samples. However, the strongest correlation (r = 0.69-0.70) significant at 0.01 level exists between specific bread volume and protein and wet gluten content, determined both by standard or by NIR methods.

Environmental samples (n = 254) were collected at regular intervals from 1994 to 1999 on three swine farms in the area of the district town Hodonín, Czech Republic. The samples of feed mixtures (n = 85), barn dust sediments (n = 44), and muscular (n = 42), hepatic (n = 41), and renal (n = 42) tissues of feeder pigs were analysed for the concentrations of mercury, cadmium and lead. The concentrations of mercury showed decreasing tendencies in animal tissue samples (1994-1996). Compared with the mean for the Czech Republic, the concentration of mercury was markedly higher in liver and kidney samples (0.064 mg/kg and 0.114 mg/kg, respectively) collected in 1998, the concentration of cadmium was moderately higher in feed, muscle, liver, and kidney samples collected in 1996-1998. Statutory limits were exceeded in two liver and two kidney samples and one feed sample only. The concentration of lead in muscle, kidney, and feed samples (1994-1996) and barn dust samples (1996-1998) showed also a decreasing tendency. However, the limit was exceeded in 16 muscle samples (0.11 to 0.23 mg/kg) collected in 1994-1999 and two kidney samples collected in 1996 (0.74 mg/kg) and 1999 (0.77 mg/kg). Heavy metals present in dust sediments apparently did not contribute significantly to their content in animal tissue. While the health risk resulting from the contents of mercury and cadmium can be classified as moderate, the contents of lead must be regarded as markedly more dangerous.

The astringent taste is important for the sensory quality of beverages. Perception thresholds of two important astringent compounds - tannic acid and (+)-catechin were determined using two procedures. The concentration-intensity dependence was linear at low concentrations and up to medium intensities of the astringent taste if unstructured graphical scales were used, but the saturation threshold was soon attained in the case of tannic acid. Recording the results on printed forms gave similar results as using a touch-sensitive monitor. The optimum tasting was achieved at swallowing after degustation of 5 s. The duration of degustation increased the intensity. The astringent flavour was suppressed by sugar, but was not significantly influenced by ethanol, citric acid or quinine hydrochloride. Astringent substances were accurately perceived and rated in wine, tea infusion and orange drink, but the increase of astringency was smaller than in model solutions. The astringent taste was easily distinguished from the bitter taste.

The aim of this work was to find out how repeated low doses of aflatoxin B1 (AFB1) and T-2 toxin would influence the Chinese hamster and if the amplifying of these effects would occur with the application of both toxins together. The animals were treated with 10 ml/kg of 7% dimethylsulfoxid (DMSO) in the control group (C), 1.0 mg/kg of AFB1 in group A, 1.0 mg/kg of T-2 toxin in group T2, and 1.0 mg/kg of AFB1 + 1.0 mg/kg of T-2 toxin in group T2/A. All mycotoxins were dissolved in 10 ml/kg of 7% DMSO. These doses were administered intragastrically twice a week for a period of three weeks. General health condition, histological picture of some internal organs, some biochemical blood serum indicators of liver and kidney functions, and leucogram were monitored. No differences in prosperity or weight gains appeared during the course of the experiment. The histological examination did not show any changes in the investigated organs in any experimental group. On the contrary, differences were found in the biochemical blood serum profile. ALT and AST activities decreased significantly in T2/A group animals compared with the other medicated groups (T2 - 24.46 µkat/l; 45.18 µkat/l; A - 18.17; 41.84; T2/A - 4.74; 14.21). A similar decrease appeared in GMT activity as well, but it was significant only in comparison with the T2 group (T2 - 0.6 µkat/l; T2/A - 0.25). ALP activity was increased in the experimental groups compared with the control, significantly in the T2 group (C - 5.0 µkat/l; T2 - 6.92). LDH activity was lower in the T2 and T2/A groups, significantly when the T2/A group was compared with the A group (A - 94.05 µkat/l; T2/A - 37.48). The cholesterol level was significantly increased in group A compared with the C and T2 groups. A smaller increase in the T2/A group was significant when compared with the T2 group as well (C - 3.05 mmol/l; T2 - 2.85; A - 3.59; T2/A - 3.27). Total and conjugated bilirubin concentrations decreased in group order A - C - T2 - T2/A, when differences among the A, T2 and T2/A groups were significant (T2 - 1.0 mmol/l; 0.36 mmol/l; A - 2.36; 0.85; T2/A - 0.69; 0.21). A glycemia decrease in medicated groups was significant in the T2/A group, while it approached a significant level in the T2 group (C - 10.46 mmol/l; T2 - 9.01; T2/A - 8.91). The main liver condition indicators seemed to be influenced by the T-2 toxin and AFB1 combination more than by individually applied toxins. We assume the amplification of the mycotoxin effects on proteosynthesis. The ALT activity especially was probably influenced more than in the additive manner. All the medicated groups showed a significant increase in the monocyte percent count (T2 - 9.8%; A - 9.62; T2/A - 8.85; C - 6.65). The differences observed in other leucocyte types were not significant. There were no differences in the effects of individual mycotoxins and their combination on the leucogram level.

The storage of lipid foods is mostly affected by the oxidation of lipid fraction. Dry foods are particularly sensitive because lipids are not protected by hydrated proteins against oxidation. A method suitable for testing dry foods was studied in model mixtures of rapeseed oil with albumin or cellulose. Oxipres apparatus was used, where the course of oxidation is monitored by changes of oxygen pressure. The end of induction period was more evident than in bulk oils as the contact of lipids with oxygen is better. The induction period was longer in mixtures of edible oil with albumin than in mixtures with cellulose. The induction period moderately decreased with increasing oxygen pressure, while the effect of sample weight was nearly negligible. The induction period length was a semilogarithmic function of reaction temperature. Variation coefficients and differences between the duplicates showed good reproducibility; they were lower in mixtures with albumin than in mixtures with cellulose, but both were of the same order as the respective values in bulk oils. At 120°C and 0.5 MPa oxygen, the induction periods could be usually measured within a working day.

The studies were performed involving qualitative and quantitative cytometric analysis of peripheral blood leukocytes in healthy carps at various stages of their ontogeny, i.e., in 3- to 29-month old carps. Three populations of leukocyte line cells were distinguished, which differed in forward scatter (FSC) and side scatter (90o, SSC) of laser light. The most abundant leukocyte pool was present in the eldest (23- to 29-month old) fish. Lower numbers of the cells were observed in the youngest (3- to 9-month old) carps while the lowest levels of the cells were detected in carps of the moderate age (11- to 21-month old). The leukocyte populations, distinguished on grounds of FSC/SSC characteristics, were suggested to correspond to lymphocytes/thrombocytes (low FSC, low SSC), granulocytes (high FSC, high SSC) and monocytes (high FSC, low SSC).

Phenolic compounds were extracted from rye caryopses with 80% (v/v) methanol. Phenolic acids were determined as free compounds and those liberated from soluble esters and glycosides. The analyses were performed using a Waters HPLC system equipped with a diode array detector (DAD). The following free phenolic acids were found: p-coumaric, ferulic and sinapic; the phenolic acids liberated from soluble esters were as follows: vanillic, caffeic, p-coumaric, ferulic and sinapic; and those liberated from soluble glycosides were the following: vanillic, p-coumaric, ferulic and sinapic. In rye caryopses, phenolic acids were chiefly in the form of soluble esters. A diode array detector was especially useful for the determination of vanillic acid: the UV spectrum of this compound showed a maximum at 260 nm whereas UV spectra of other phenolic acids were characterised by maxima at longer wavelengths.

Total content and composition of essential oils in caraway seed (Carum carvi L.) from a selection of caraway varieties grown in different production areas were determined after supercritical fluid extraction (SFE) and steam distillation. Different procedures of sample pretreatment (homogenization) and methods of isolation were compared from the point of view of efficiency, reproducibility and accuracy. The effect of storage period was also examined.

Experimental groups of pigs were treated orally with 120 mg (Group O 120), or 480 mg (Group O 480) of iodine per animal, or intramuscularly with 240 mg (Group I 240) of iodine per animal. Iodine was administered in the form of iodised fatty acid esters (IFAE). The treatment resulted in significantly increased iodine concentrations in tissues and a single dose was sufficient to meet the requirement for the whole fattening period (180 days). Urinary iodine concentrations in all the experimental groups were higher than in the control group C receiving iodine only from conventional feed. Urinary excretion of iodine between days 2 and 5 was more distinctive in orally treated than in intramuscularly treated animals (Figure 1). Iodine concentrations at the end of the fattening period (day 180) were higher in the treated than in the control groups. The treatment effect was more marked in Groups O 480 and I 240 than in Group O 120. The dynamics of blood serum iodine concentrations was similar to urinary concentrations (Figure 2). Mean thyroid gland weights in the groups O 120, O 480, I 240, and C were 9.19, 8.51, 7.10, and 12.01 g, respectively. An opposite tendency was observed for iodine concentrations in thyroid gland dry matter (Figure 3). No effects of any of the treatments on total protein, albumin, total lipids, or cholesterol concentrations in blood serum were observed. Group C showed lower tissue iodine concentrations than any of the experimental groups. The only exception was hepatic tissue in which approximately the same iodine concentrations were found in all the groups. Data obtained in Groups O 120, O 480, and I 240 indicate that decisive for tissue concentrations was rather the dose of iodine than the route of administration. Iodine is stored above all in the thyroid gland and adipose tissue. As can be seen in Figure 4, its concentration was higher in muscles with a higher proportion of fat (neck) than in lean muscles (ham).

A programme for evaluating the strict morphological analysis of sperm was developed. The programme was verified by conducting 552 morphological analyses of bull, stallion, boar and human ejaculates. The method was evaluated by comparing the results obtained by routinely used morphological examinations with the results received by the automatic method SASMO. The following advantages of the programme were demonstrated: it is possible to obtain information on the proportion of normal and pathological spermatozoa, to determine the frequency of the respective characteristics analysed, to express detected alterations per pathological spermatozoon (teratosperm index), to express frequency of respective alterations per total number of spermatozoa examined, to display alterations according to their frequency and differentiate between developmental and acquired alterations. It was proved that using the detailed morphological evaluation of sperm by the survival test, it is possible to get statistically significant information on the prediction of sperm survival. The programme represents an important aid for making the morphological evaluation of sperm quality more objective both in veterinary and human medicine and in all insemination stations and assisted reproduction centres.

During 1997-1998, the reaction of the collections of winter and spring wheat varieties to Tilletia caries was determined. In both years the most diseased winter varieties were Simona and Sparta, the least diseased were Samara and Ilona. High variability in the level of infection was observed in some varieties (VIada, Estica, Regina, Vega). No winter wheat variety was completely resistant. The most diseased spring wheat variety was Alexandria in both years, while Grandur showed no infection. High variability in the level of infection was observed in the special trials with cv. Ina and Contra. In trials of the efficacy of seed dressing against T. caries and T. laevis there was variability only in the controls, but not in dressed variants.