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Specific productivity and some correlations between growth and productivity were evaluated in a set of 24 apricot (Prunus armeniaca L.) genotypes in 1994-1999. Even though the planting stock came from the same nursery, was of even age and on the same rootstock, the tree size of genotypes varied from planting to a permanent site. Differences in the tree size of genotypes slightly diminished over the six-year period, likely under the influence of uniform pruning used for all trees. Nevertheless, tree size evaluated from the area of stem cross-section can be considered as a genotype disposition. It is proved by a positive, highly significant correlation (r = 0.84⁺⁺) between the rank genotypes according to the area of stem cross-section in the fourth and eleventh year after planting. Confidence intervals also confirmed significance of differences in specific productivity. In total, specific productivity of twelve genotypes was significantly higher than in the control cultivar Velkopavlovická. A negative, significant moderate correlation (r = -0.40⁺) was calculated between tree size and specific productivity expressed as yield weight per unit area of stem cross-section. Weakly growing genotypes had higher specific productivity. The highest specific productivity was recorded in cultivars Vynoslivyj and Priusadebnyj and in LE-1321 and LE-390 hybrids. Of them, the most interesting for producers and fruit quality was Vynoslivyj with average fruit weight 47 g and harvest ripeness 11 days after Velkopavlovická.

Laboratory experiments were carried out with seeds of Galinsoga ciliata and Chenopodium album in 1998, 2000 and 2001. The study involved germination of non-dormant seeds in the light and the dark at 5-30°C, the germination energy at 15, 24, and 33°C, and the primary dormancy of seeds matured during the period from July to October. Both weeds germinated better in the light compared to the dark. Seeds of G. ciliata germinated at 10-33°C. Germination exceeding 85% was recorded at 12-28°C. Ch. album germinated in a wider temperature interval (5-33°C). Maximum germination (75%) was obtained at 18°C. A very high germination energy of G. ciliata seeds was found at 24°C. At this temperature, 89% of seeds germinated during the second and third day of the germination test. Seeds of Ch. album had a low germination energy at 15 and 24°C. The germination energy was high only at 33°C, however, the total germination reached at this temperature was only 26.5%. Both G. ciliata and Ch. album formed primary dormant seeds during all three testing years. The length of primary dormancy varied from 10 to 100 days depending on the date of ripening and on the year. The longest primary dormancy was found with early ripened seeds (July and August).

This study was performed on 24 clonal rootstocks and 4 scion apple cultivars to evaluate rootstock/cultivar combinations for susceptibility to fire blight (Erwinia amylovora). For this aim, the clonal rootstocks were planted in plastic greenhouse in 1992 and grafted with 4 cultivars (Golden Delicious, Dulcit, Domino and Dione) in 1998. A total of 96 rootstock/cultivar combinations were tested during 1998-2001. Each year, 10 to 30 actively growing shoots per one combination were inoculated with the pathogen. The shoots were inoculated by cutting through first unfolding leaves with scissors dipped into inoculum (109 cfu/ml). The trees were misted to create a high relative humidity. The susceptibility of the test roostock/cultivar combinations was evaluated by calculating the length of necrosis to the total shoot length 40 days after inoculation. The degree of susceptibility of cultivar tested varied depending on the rootstocks and years. In order of decreasing to increasing levels of fire blight susceptibility of four cultivars tested, the pattern observed was Dulcit, Golden Delicious, Domino (moderately susceptible) and Dione (very susceptible). The lowest susceptibility of four cultivars tested was observed on TE 52 rootstock (on average, the cultivars were evaluated as intermediate), the highest susceptibility was on JTE-E and M9 rootstocks (the cultivars were very susceptible). The influence of 21 remaining rootstocks on susceptibility in scion cultivars was not marked. Thus some rootstocks can render the scion cultivars more fire blight susceptible or more resistant.

Humerus, tibia and antebrachium fractures determined in 30 dogs of different breed, age, weight and gender were treated using Type I and II external fixators. Meynard and handcuff clamps were used in the external fixators. Limited open approach was applied in 6 of the cases and closed reduction techniques in 24. In cases where closed reduction and stabilisation was done, the patients were seen to use their leg within 3-10 days post-operatively and that walking was reasonably good after 20 days. In cases to which a limited open approach had been applied, use of leg was achieved in a period close to the closed method.

The cabbage-carrot juices were inoculated with Lactobacillus plantarum 92H at the concentration of 8 × 106 CFU/ml and fermented in a thermostat at 24°C for 150 hours. During the fermentation, both analytical (pH, total acidity, reducing sugars, l-ascorbic acid, lactic, acetic and citric acids, biogenic amines) and sensory (appearance, colour, turbidity, sediment and taste) parameters were followed. For the evaluation of the results of the chemical and sensory (taste) analyses of these juices the multivariate statistical methods were applied. PCA and FA reduced the 7 original analytical variables to 1 independent component (factor) that accounted for 96.92% of the total variance, and CA divided samples into 2 groups according to the contents of lactic and acetic acids. PCA and FA reduced the 8 taste and mixture taste descriptors to 2 components (factors) that accounted for 97.28% of the total variance.

Fourteen Potato virus Y (PVY) isolates were characterized. They represented PVYN strain only. However, application of serological and molecular genetic methods led to a more complicated characterization. For example, five isolates induced necrotic symptoms on tobacco plants typical of PVY^N, despite reacting as PVY^O serologically. Moreover, the PVY isolates were not identical according to molecular genetic properties. Typical PVY^NTN PCR products were observed for 11 isolates, but four of them (Hr220-5, Hr387-7, Nord 242 and Syn1Scot) did not produce potato tuber necrotic symptoms in infected cultivars. An immunocapture RT-PCR probing was developed using a set of 24 primer pairs derived from eight regions of the PVY genome. Using this method, five out of seven PVY^NTN isolates including the Czech standard PVY^NTN from the potato cv. Nicola were found to be identical. However, two PVY^NTN isolates and all the other probed PVY samples showed unique patterns, suggesting specific differences at the nucleotide level. This method enabled specific identification of individual isolates variability even within different PVY strains.

The effect of two priming techniques: hardening (prehydration treatment) and solid matrix priming (SMP) was studied on the seeds of two parsley varieties (Cukrowa and Berlińska) in 3-year laboratory experiments. On the images obtained from scanning electron microscope (SEM) there is a parsley embryo developing during germination up to the moment of radicle emergence. On the surface of primed seeds, in particular using the hardening method, lateral cracks are visible. The respiratory activity of primed seeds was similar to that of non-primed in the period of initial 24 h of germination, but significantly higher after 48 h. As compared to non primed seeds solid matrix priming significantly increased the percentage and the speed of germination. Nevertheless, pelleting reduced the positive effect of priming on the germination ability, without affecting the germination speed. After 18 months of storage, the vigour of primed seeds, particularly through hardening, had significantly decreased.

The occurrence of Erysiphe cichoracearum (Ec) and Sphaerotheca fuliginea (Sf), causal agents of cucurbit powdery mildewin the Czech Republic (CR) was studied in the period of 1995-2001. Nearly 800 leaf samples with disease symptomswere microscopically examined. Ec is the predominating species, detected on 98% of locations. It was accompanied by Sfon 24% of locations. The occurrence of Sf as the only powdery mildew species was proved on 2% of locations. Recentoccurrence of Sf in the CR corresponds with data on Sf fast spreading and prevailing on cucurbits in West and SouthEurope. However, Ec is the strongly predominating powdery mildew species largely distributed throughout the country.The hyperparasitic fungus Ampelomyces quisqualis was detected on 30% of samples.

The influence of inoculation techniques on induction of post-infection ethylene production in susceptible and resistant genotypes of bean (Phaseolus vulgaris) inoculated with the kappa race of Colletotrichum lindemuthianum was studied. Three inoculation methods (brushing, dipping and spraying) of excised leaves were compared. The brushing technique caused both the highest ethylene production at 120 h after inoculation, and better symptom development than dipping and spraying. It was, therefore, adopted to determine the post-infection ethylene production in four inoculated bean genotypes (GLP406 and Kaboon - resistant, GLP636 - moderately resistant; and MDRK - susceptible). Ethylene production increased slightly 24 h after inoculation in all four genotypes, followed by a rapid decline after 48 h. Ethylene production remained low until 120 h after which a sharp rise was observed in genotype MDRK. Increased production, though to a lesser extent, was observed in GLP636. This trend was repeatable and thus may offer an additional physiological marker to bean breeders to screen for resistance to C. lindemuthianum.

Weight, height, width and diameter of fruits and stones were evaluated in 21 apricot cultivars and hybrids in 1994-1997. Statistically significant differences between the measured values of traits confirmed their applicability for objective characterization of genotypes. The evaluated traits are genetic dispositions. It was also proved by the rank of genotypes arranged according to the values of particular traits in one year that was highly significantly identical in the other years of the evaluated period (correlation coefficient r = 0.45⁺⁺ to 0.87⁺⁺). The relationship between fruit weight and other traits (stone weight, stone height and stone width) is not linear. Fruit weight increases (or decreases) faster towards the limit values of traits. The average percentage proportion of stone weight in fruit weight ranged from 4.9% to 9.6% in the genotypes over the period of four years. A lower proportion of stone in fruit weight is a positive trait for selection of suitable genotypes for direct consumption and flesh processing. This trait can also be a suitable criterion of genotype selection to breed cultivars with a low proportion of inedible part. Promising cultivar Lemeda is an example of the low stone proportion in flesh weight. A high level of variability was found in the values of stone and fruit weight (coefficient of variation v = 19.00% and v = 24.74%, respectively). Coefficients of variation for other traits (fruit and stone height, width and diameter) were by more than a half lower.

Forestry and Game Management Research Institute at Jíloviště-Strnady has created a new experimental base for thinning research since 1956. A total of 46 experimental series were founded in Norway spruce (Picea abies [L.] Karst.); 24 series are still maintained. This paper focuses on the series established in young Norway spruce stands in 1958 (Rumburk, Mostek, Vim­perk I, Vimperk II and Nisa). The goal of thinning experiment was to compare two basic methods of thinning: positive selection from above (2a) and negative selection from below (3b or 5b). Each experimental series has a control plot (1c) where no thinning was conducted. The effect of thinning by positive selection from above carried out in the 40-year period of investigations was a 10-45% decrease in the abundance of trees in lower diameter classes compared with control plots. Negative selection from below resulted in a more pronounced decrease in thin trees abundance (50-69% compared with control plots). The abundance of thick trees (diameter of 30 cm and more) increased by 5-50% on all comparative plots with thinning. Static stability characterised by the h/d ratio of mean stem and h/d ratio of dominant trees (200 thickest trees per hectare) was influenced by thinning mostly positively (final value of h/d ratio found by the last revision was considerably lower).

The corpus luteum (CL), formed from the ruptured follicle, is required for the course of normal cyclicity and the duration of pregnancy in females. The influence of a mixture of polychlorinated biphenyls - PCBs (Aroclor-1248) - on the secretory function of CL (dispersed bovine luteal cells) during different stages of the estrous cycle was studied. The cells (1.2 × 105/ml) were pre-incubated for 24 h and were then treated with 10, 100 or 500 ng/ml of PCBs. A􀄞er 24, 48, 72, 96 or 144 h luteinizing hormone (LH; 100 ng/ml; positive control) was added to the medium. The most evident impaired secretion of progesterone was measured after 72 h of incubation with PCBs and this time was selected for the further experiments. In Exp. 2 high density lipoproteins (HDL), as a source of cholesterol (25 μg), increased progesterone secretion from luteal cells; PCBs enhanced this effect in mid and late stage of the estrous cycle. PCBs had no effect on the stimulatory influence of LH, which itself stimulated progesterone secretion. In Exp. 3 PCBs (500 ng/ml) decreased progesterone secretion from the early CL and increased stimulatory effect of noradrenaline (NA) on progesterone secretion from mid CL. Aroclor-1248 stimulated oxytocin (OT) secretion from all stages of CL development. NA alone increased OT secretion from mid and late CL and moreover, it amplified effect by Aroclor on CL from all studied stages of their development. We conclude that the mixture of PCBs, commercially available as Aroclor-1248, can directly impair the function of bovine CL and thus it can affect the estrous cycle duration or embryo development.

Aiming at determination differences in leaf and root potassium concentration of diverse sugar beet genotypes as well as its effect on sugar beet root quality and yield. Investigations comprising 15 sugar beet genotypes (five multigerm lines, five hybrids and five monogerm lines) were carried out on two soil types (Calcic luvisol: L-1 and L-3 and Calcic gleysol: L-2 and L-4) during two growing seasons. Root yield of the investigated genotypes on Calcic luvisol (50 t/ha) was higher, than on Calcic gleysol (34 t/ha). In general, multigerm lines were known for the highest leaf potassium concentration (2.75%), lowest root one (3.78 mmol/100 g root), highest sugar content (13.8%) and best root extractable sugar (1.5%). Monogerm lines had the lowest leaf potassium concentration (2.51%), highest root one (4.24 mmol/100 g root), lowest sugar content (12.9%), and the poorest extractable sugar (10.7%). Root yield of the investigated hybrids (48 t/ha) was higher by 16% compared to multigerm lines yield (42 t/ha) and as much as 35% higher compared to monogerm lines (36 t/ha). Sugar beet root potassium was in significantly negative correlation with sugar content at three localities (L-1: r = -0.485**, L-2: r = -0.096, L-3: r = -0.687**, L-4: r = -0.337**) whereas at all four localities it was in negative correlation with extractable sugar (L-1: r = -0.634**, L-2: r = -0.407**, L-3: r = -0.930**, L-4: r = -0.749**). Potassium concentration in sugar beet leaf was in significant positive correlation with sugar content at three localities (L-1: r = 0.382**, L-2: r = 0.231, L-3: r = 0.717**, L-4: r = 0.516**).

Field trials were conducted at two sites Troubsko near Brno and Prague-Ruzyně in 1996-1999 with three varieties of safflower (Gila, CW-74, Sironaria). Three rates of nitrogen fertilization were used: N0 = no fertilization, N₁ = 40 kg/ha, N₂ = 80 kg/ha. Sowing rates were 50 and 70 germinable seeds per m2. The average values of oil content were highest in seeds of CW-74 variety (27.2%). Gila had on average the lowest oil content (24.5%). Linoleic acid was dominant in all three safflower varieties. Variation in content of linoleic acid in different years was not so high as in oil content. The highest average content of linoleic acid was found in Gila variety (81.2%), the lowest in Sironaria (77.4%). At Ruzyně average seed yield on dry basis was 2.7 t/ha and average straw yield was 7.56 t/ha. At Troubsko seed yield was 2.56 t/ha and straw yield was 3.69 t/ha (by 50% lower than at Ruzyně). The effect of year of growing and site on seed yields and on other parameters was highly significant. N fertilization increased safflower seed yield at Troubsko site only, where the dose of 40 kg/ha N increased the yield by 0.08 t/ha on average of years and the dose of 80 kg/ha N increased the seed yield by 0.2 t/ha in comparison with no nitrogen fertilization treatments. Increased N rates and especially higher plant density resulted in an increase in straw yields. Neither were thousand seed weight nor number of flower heads influenced significantly by different N rates or the above-mentioned differences in plant density.

Ecology of capercaillie (Tetrao urogallus) was studied in the mountains of Central Slovakia (West Carpathians) in 1981-2003. In the studied area, the capercaillie population inhabited especially old natural forests (100-250 years old) in the spruce-beech-fir (850-1,270 m a.s.l.) and spruce (1,250-1,530 m a.s.l.) vegetation zones. The overstorey stand age ranged between 80 and 250 years with the mean of 128 years. The understorey stand age ranged from 10 to 60 years. The overstorey tree density ranged between 200 and 1,050 stems per ha (mean 725). The understorey tree density ranged from 5 to 650 trees per ha (mean 290). Both males and females preferred old forests throughout the year. The results demonstrate a marked decrease (> 50%) in the numbers of cocks and hens on twelve monitored leks (28%) and a slight decrease (< 50%) on ten display grounds (24%). During the study period, capercaillie cocks became extinct on seven (16%) leks and in their surroundings. More or less constant numbers were found on twelve leks only (28%) and a slight increase occurred on two leks only (4%). A statistically highly significant correlation was found between the area of old-growth forest and the number of cocks attending a lek. In addition to forest deterioration predation appeared to be of major importance in limiting the numbers of capercaillies. Key points for forest management in relation to capercaillie protection are suggested.

The evaluation of effects of some non-genetic factors (sex, litter size, age of dams and year of study) on the growth of 85 kids of the Brown Short-haired breed was carried out in a period of two successive years. The analysis of the growth of all kids revealed that in the time interval from birth to Day 90 of age daily gain and final body weight were 181.3 g and 19.52 kg, respectively. As far as the effect of sex was concerned, the intensity of growth was significantly higher in males than in females (P ≤ 0.01) in all periods under study. From birth to Day 90, the respective daily gains of males and females were 200.6 g and 162.0 g. As far as the litter size was concerned, it was found out that daily gains of singles and triplets were higher than those of twins and that the differences between single kids and twins were significant (P ≤ 0.01) in all periods under study. Specifically, daily gains of single kids, twins and triplets in the time interval from birth to Day 90 were 201.4 g; 167.1 g and 175.6 g, respectively. The analysis of the effect of age of dams on daily gains revealed significant effects of this factor on daily gains in the time intervals of Day 30 - Day 60; Day 60 - Day 90; Day 30 - Day 90 and from birth to Day 90 (P ≤ 0.05). With the exception of the period from birth to Day 30, the highest daily gains were recorded in kids of four-years-old dams in all other periods under study. In both years of study, all kids were reared under nearly identical conditions but the effect of year of study on the growth was significant.

Hair roots are a very attractive source of DNA for microsatellite-based parentage control of breeding animals. However, unlike blood samples, irregular DNA typing results have been observed in assays utilizing hair follicles. The amount of starting material and DNA preparation method are the crucial factors. In order to improve DNA typing results for horse hair roots, two quick preparation methods and additional purification steps were evaluated. PCR efficiency for each approach was expressed as percentage of samples with complete DNA profiles for 12 horse microsatellites. The lowest percentage (22%) of complete DNA profiles was obtained for samples prepared by the proteinase K digestion method. The best genotyping results (94%) were achieved after phenol-chloroform extraction of DNA from samples prepared by the proteinase K digestion method. Direct cleanup of DNA samples with an ethanol-sodium acetate mixture gave comparably good results of microsatellite genotyping (91%). DNA preparation from hair roots with proteinase K digestion followed by DNA purification with ethanol was chosen as the most efficient approach for horse DNA typing under parentage testing.

Viruses cause many diseases in plants, animals, and humans. They are strict intracellular parasites with cellular specificity. Viral particles can be transmitted by different routes, such as contaminated food and water. People usually get infected orally, after ingestion of products contaminated during processing or subsequent handling or preparation. This review article is focused on the most severe foodborne viruses specific for humans, of the following genera: Norovirus, Enterovirus, Hepatovirus, Astrovirus, and some others. Methods for detecting viruses in food and strategies for preventing virus transmission via food are also discussed.

Fifty one products of dried milk baby food purchased from 10 producers from seven countries available on the Czech market have been tested. IS900, the specific fragments for Mycobacterium avium subsp. paratuberculosis (MAP) have been detected using PCR in 25 samples (49.0 %) and fragment f57 by real time PCR in 18 samples (35.3%). These results correspond to the epidemiological situation in Europe and are not unexpected. Paratuberculosis in cattle was almost unknown in the Czech Republic until 1990. An increase in the number of cows with paratuberculosis found in slaughterhouses and the incidence of Crohn's disease in the last decade is evident. The possible risk of MAP dead cells or bacterial structures in food is discussed in respect to autoimmune Crohn's disease. The national programmes of paratuberculosis control and certification of paratuberculosis-free herds should be strongly supported to decrease the risk for children and other people under higher risk. Producers should use MAP free milk for baby food production on a voluntary basis.

Neospora caninum is a protozoan parasite causing bovine abortion all over the world. The aim of this study was to investigate how common N. caninum infection is among dairy herds in the Czech Republic. Bulk milk samples were collected from 495 dairy herds and analysed for the presence of specific antibodies by a commercial N. caninum iscom ELISA. Five out of 495 dairy herds (1.01%) had percentage positive values ≥20 and were considered positive. In the positive herds, blood samples were collected from cows and pregnant heifers and analysed by the ELISA test. The within-herd seroprevalence ranged from 2.5 to 50%. The bulk milk ELISA could be a useful and inexpensive method for rapid screening of Neospora caninum infection in dairy herds in large areas.

The yield, cluster drop and nut traits of the hazelnut cultivars Tombul, Palaz and Çakildak in Turkey were examined during 2001-2002. The cluster drop ranged from 7.5 to 17.0%. The highest yield per shrub with 2,930 g in 2001 and 3,190 g in 2002 was found in cultivar Tombul. This cultivar was also better in terms of the studied fruit traits compared with the other cultivars. In this cultivar (in 2001 and 2002), nut numbers per cluster were 3.87 and 3.46, nut weights were 1.53 and 1.70 g, kernel weights 0.93 and 0.99 g, and kernel proportions were 50.9 and 53.8%.

The subject of our research was to verify effects of the mechanical preparation of soil in the natural regeneration of pedunculate oak in a floodplain forest. On the site of a hard-wooded floodplain forest at the confluence of the Morava and Dyje rivers (Czech Republic), several sample plots were established differing in the preparation of soil during regeneration, in weeding the plots and in the period of the implementation of soil surface scarification before and after the fall (or distribution) of acorns. On the basis of results obtained, mechanical preparation of soil on non-weed-infested plots in the heavy seed year is not necessary, however, it supports seedling emergence from acorns and eliminates weed tree emergence and weed. However, it is better to realize it only after the fall of acorns and to incorporate them into soil and thus their emergence will be increased. Soil scarification can be carried out also in the course of harvesting the parent stand through the extraction of wood and slash from the regenerating area. In weed-infested stands, however, the thorough preparation of soil before the fall of acorns appears to be a necessity.

In the past ten years, meat and meat products consumption has changed dramatically. It has been caused by price and non-price factors. This article gives a brief recapitulation of the development of the consumption of meat and meat products and identifies the key factors which, in the past ten years, have had a major impact on this development. This article presents results of the secondary data analysis and the results of an inquiry into meat and meat products consumer behaviour carried out in the late 2004.

A total of 60 random samples of fresh chicken burger, fillet, and luncheon (20 of each) were collected from markets at Tanta city. The average total yeast counts (cfu/g) in burger, fillet, and luncheon samples were 2.7 × 10⁶ ± 1.1 × 10⁶, 2.1 × 10⁵ ± 0.9 × 10⁵, and 1.4 × 10⁷ ± 0.7 × 10⁷, respectively. A total of 158 yeast isolates of 23 species were isolated and identified. Candida, Cryptococcus, Debaromyces, Issatchenkia, Pichia, Rhodotorula, Saccharomyces, Trichosporon and Yarrowia species were recovered from the examined samples of fresh chicken meat products in varying percentages ranging from 5% to 50%. The tested plant extracts of cinnamon, clove and thyme revealed a potent anti-yeast activity against C. albicans, D. hansenii and S. cerevisiae at 20% concentration, and a moderate inhibitory activity against these yeast strains at 10% concentration, while garlic extract had a lesser inhibitory effect on the yeast strains tested at the same concentration. Moreover, thyme, cinnamon and clove extracts had a complete inhibitory effect on chicken fillet inoculated with Candida albicans when incubated at 5°C and 25°C.

A total of 36 samples of feed - 19 samples of hays and 17 samples of silages were used for estimation of in vivo and in vitro digestibility. The organic matter digestibility (OMD) was estimated by in vivo and two in vitro techniques (method of Tilley and Terry and two-stage pepsin-cellulase method (Pepcel)). The regression equations were calculated from the results obtained in the experiment. Tilley and Terry method provided consistent results of OMD estimation for both the groups of roughages: in vivo OMD = 14.7 + 0.782 × [Tilley and Terry] (n = 18; R² = 0.76); in vivo OMD = 36.3 + 0.513 × [Tilley and Terry] (n = 16; R² = 0.75) for hays and silages, respectively. Different accuracy was found out in Pepcel method: in vivo OMD = 37.0 + 0.478 × [Pepcel] (n = 19; R² = 0.49); in vivo OMD = 37.8 + 0.484 × [Pepcel] (n = 17; R² = 0.87) for hays and silages, respectively.

The present study deals with the use of high-grain diets with a low proportion of fodder for fattened cattle, and with the evaluation of their effect on the growth intensity and metabolic profile of the animals. Thirty Holstein × Czech Pied bulls were given diets containing from 86.69 to 88.54% concentrates based on crushed cereals in the period from 216^th to 327^th day of age. The growth intensity of bulls was high, with the average daily weight gain of 1.64 kg in the course of the whole experiment. When the average body weight of animals reached 343.67 kg and 450.93 kg, blood samples were taken from the vena jugularis of 10 randomly selected animals for the assessment of acid-base balance and selected biochemical parameters. Slightly decreased pH values and increased pCO₂ were detected by the assessment of acid-base balance. The calculated values of base excess and standard bicarbonate were in the reference range; however in samples of the second collection a highly significant decrease was found (P ≤ 0.01). By a biochemical analysis of blood increased levels of plasma phosphorus were detected in samples of both collections in comparison with the accepted reference range. A statistically highly significant increase (P ≤ 0.01) in plasma urea concentrations was detected in samples of the second collection. Other investigated parameters ranged within the accepted reference values. The results of the experiments show that high-grain diets produced intensive growth with high daily weight gains, without adverse effects on the health status of the investigated bulls. Although some depletion of compensatory mechanisms maintaining the acid-base balance was recorded, no serious disturbance of metabolic profile was registered in the animals.

Contamination of cell cultures and sera used for animal virus propagation with mycoplasmas represents a serious problem, especially in virology. Therefore specific control measures must be used. To achieve this we introduced PCR for the detection of mycoplasma species in cell cultures and compared its results with ELISA and microbiological culture. Seven mycoplasma species which are the most common contaminants of cell lines (Mycoplasma arginini, M. fermentans, M. hyorhinis, M. bovis, M. orale, M. hominis, and Acholeplasma laidlawii) were used to verify the method. Then we assessed five selected cell lines and three bovine sera by the PCR, ELISA and culture methods and compared the results. PCR was positive for all of the mycoplasma species tested. ELISA kit used (Mycoplasma detection kit, Roche, Germany) allowed detection of only four species of contaminating mycoplasmas (Acholeplasma laidlawii, Mycoplasma arginini, M. hyorhinis, and M. orale). All the methods detected contamination of the VERO and RK13 cell lines. The agents of contamination were determined by the species-specific ELISA kit as Mycoplasma arginini and M. orale, respectively. Other cell lines and sera tested were not contaminated with mycoplasma. The results confirmed that the PCR method used in the present study is a sensitive, fast and specific detection method of mycoplasma contaminations and is suitable for routine mycoplasma detection in cell cultures and bovine sera.

The objective of this study was to investigate the development of rumen mucosa and the level of plasma IGF-1 in calves induced by different amounts and types of milk replacers and solid diet. Forty-five male Holsteincalves 7 days of age were assigned to three groups: group I milk free replacer, late weaned; group II milk free replacer, early weaned, and group III milk replacer, early weaned. All animals received additional concentrate, water and maize silage were offered ad libitum. In each group, three calves were slaughtered at 41 days of age. The concentration of ruminal total SCFA and the molar proportion of butyrate did not differ between the groups, but the molar proportion of acetate was lower (P = 0.01) and the proportion of propionate was higher (P = 0.02) in early weaned calves. Compared to the late weaned calves (group I) the length, width and surface of the papillae of atrium ruminis, the length and width of the papillae of ventral ruminal sac and the length of the papillae of ventral blind sac were greater (P < 0.05) in the early weaned calves fed low amounts of milk and high amounts of concentrate (group III). Furthermore, there was a tendency of plasma IGF-1 concentration to be increased (P = 0.1) in early weaned calves. The plasma levels of glucose and insulin were decreased (P < 0.01, and P = 0.03, respectively). Positive correlations existed between papillae length and plasma IGF-1 concentrations (P < 0.10). Insulin and glucose concentrations were negatively correlated with parameters of papillae development (P < 0.1). In conclusion, the development of rumen papillae was stimulated in calves consuming increased amounts of concentrate. The effect was not correlated with the molar proportion of butyrate, but with the molar propionate proportion in the rumen and with the plasma IGF-1 concentration

Host range and growth of two Ditylenchus dipsaci (Stem and Bulb Nematode) populations on onion, garlic, leek, spinach and chicory were compared. Inoculation was conducted by placing a droplet of 1.5% CMC suspension containing nematodes between the first leaves. The life cycle of the parasite was completed in variants of the original host plants, i.e. salad chicory was infected with the chicory population, and garlic and onion with the garlic population. Survival of the nematodes on garlic and spinach inoculated with the chicory population, and on chicory inoculated with the garlic population was determined. Nematodes of the chicory population did not survive on onion and leek, nor did the garlic population survive on spinach and leek. Nematode infection did not affect the dry weight of aboveground parts of plants, although a reduction would probably occur if the experiments had lasted longer. Symptoms of the infections were apparent in chicory inoculated with the chicory population. Nematodes in the substrate in which the plants were grown were found only in those variants with plants in which the life cycle was completed.