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Essential oils are aromatic oily liquids obtained from plant material (flowers, buds, seeds, leaves, twigs, bark, herbs, wood, fruits and roots). Besides antibacterial properties, essential oils or their components have been shown to exhibit antiviral, antimycotic, antitoxigenic, antiparasitic, and insecticidal properties. In this experiment the effects of supplementation of the diet for laying hens with thyme and hyssop essential oils on physical and microbiological egg parameters were studied. Hens of laying hybrid ISA Brown (n = 72) were randomly divided at the day of hatching into 3 groups (n = 26) and fed for 41 weeks on diets which differed in kind of essential oil supplemented. In the first experimental group the feed mixture was supplemented with thyme essential oil addition 0.25ml.kg^-1, in the second one got hyssop essential oil the same dose of 0.25ml.kg^-1. The results suggest that the supplementation of thyme essential oil into laying hens diet statistically significantly increased egg albumen weight, egg albumen percentage portion (P < 0.05) and egg yolk colour (9.07^a, 9.47^b, 9.06^a; P < 0.01), compared to the control group and decreased egg yolk percentage ratio. However, the most of qualitative parameters of internal content egg were not with thyme and hyssop essential oils addition significantly influenced. Significant differences in microbiological indicators were found among coliforms bacteria, enterococci, total number count (P < 0.001), lactobacilli and mesophilic sporulating aerobes bacteria (P < 0.05).

Casein measurement is important for cheesemaking and control of dairy cow nutrition. Reference Kjeldahl method is not suitable for routine purposes. Infra-red spectroscopy MIR and MIR-FT use can be a solutin. However, their casein specifity is relatively limited. Aim of the work was to assess the quality of performed calibrations for validation of calibration parameters. A retrospective analysis of MIR and MIR-FT calibrations was performed for estimation of limits their suitable parameters. Mean casein values of reference sample sets varied from 2.49 to 2.7% (2.61 ± 0.155). Mean variation range was 0.561 ± 0.164%. The mean correlation coefficient of calibration (KKK) was 0.974 ± 0.018 (P < 0.001). The mean standard deviation of mean for individual differences (SDID) was 0.03 ± 0.011% (from 0.01 to 0.08). MIR-FT results were slightly better both for calibration and for proficiency testing. The high and low KKKs were higher in the case of accepted calibration as in proficiency testing for MIR-FT and MIR (0.986 > 0.964 and 0.970 > 0.948; 0.982 > 0.947 and 0.947 > 0.911; P < 0.001). The casein number varied from 79.4 to 80.56% in bulk milk samples in three years, its variability was low from 1.4 to 1.5% relatively, which shows on relatively reliable casein analyses by methods MIR and MIR-FT. It does not need to agree fuly for individual milk samples. It is linked more to MIR than MIR-FT. Limits for acceptable calibration parameters were derived: > 0.945 for KKK; 0.048 for SDID and 0.029% for mean difference as maximum.

The objective of this work was to find an effective method of polyploidy induction using chemomutagens, colchicine and oryzalin, in diploid cultivar of Phlox paniculata 'Fujiyama' (syn. Mt. Fuji, Fuji). Ploidy level was determined by the flow cytometry method (FCM). Two methods of treating the explants (in vitro regenerated shoots) were tested; chemomutagen infiltration from nutrient media ("the infiltration method") and dipping of the explants in a chemical mutagen solution ("the dip method"). The highest values of tetraploid (5%), mixoploid (1.67%) frequency and polyploidization efficiency (1.25) were found in explants treated with 0.2% colchicine for 24 h in the dip method. Concentrations of 10 µM oryzalin and 0.2% colchicine for 14 d were the most effective for obtaining tetraploids in the infiltration method. The results will be exploited to other P. paniculata cultivars for breeding of this species.

The objective of this experiment was to determine the ruminal degradability of starch using the in vitro method. Maize silages from whole plants (MS), maize cob silage prepared by ensiling of the cobs with bracts (MCS), and maize grain silages (MGS) were compared with maize grain (MG). The tested feeds differed in total starch contents. Averaged starch contents with standard deviation values were 343.3 ± 18.7 g/kg for MS; 522.0 ± 8.9 g/kg for MCS; 727.9 ± 16.9 g/kg for MGS; and 682.8 ± 22.6 g/kg dry matter for MG. The in vitro ruminal degradability of starch was determined by the feed incubation period - for 2, 4, 6, 16 and 24 hours. The higher degradation was observed at the 4-h of incubation for maize silage from whole plants (46.6 ± 4.9 %), maize cob silage (41.2 ± 1.6 %) and maize grain silage (39.7 ± 1.4 %) as compared to maize grain (32.0 ± 1.0 %). Enhanced values of the in vitro ruminal degradability of starch continued to increase until the 24-h of incubation, when the differences between silages and maize grain were balanced. A significant difference of the curves of degradability profile was found between silages and maize grain (P < 0.0001) but was not significant between MS, MCS and MGS.