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D Rysánek

Publications and source records attributed to D Rysánek.

At least 19 recordsLinked to original sources
PubMed2005

Effects of certain inducers of leukocytes migration into the bovine mammary gland on neutrophil apoptosis manifestation in a subsequent in vitro cultivation.

The aim of the study was to elucidate the effects of induced leukocyte migration into the bovine mammary gland on the manifestations of early and late apoptotic features of neutrophils cultivated in vitro. The Latin square design was used in two experiments, each involving four experimental repetitions in 4 clinically healthy virgin heifers. The neutrophil early apoptotic features were detected by flow cytometric detection (FCM) of phosphatidyl-serine translocation. Late neutrophil apoptotic features were detected by ELISA quantitation of histone-complexed DNA fragments. Leukocyte influx induction was accomplished by using four inducers: i) sterile buffered saline solution (PBS); ii) 5 % glucose solution (GLU); iii) synthetic muramyl dipeptide analogue (MDP); and iv) lipopolysaccharide (LPS), administered into the mammary gland lumen. Leukocytes from mammary glands were obtained by mammary gland lumen lavages after influx induction. The total cell counts in lavages increased after treatment by all inducers in comparison to the counts before influx induction (P<0.001). Cell counts were higher and differed significantly by MDP and LPS (P<0.01) in contrast to PBS. The highest proportion of neutrophils was induced by LPS (P<0.01). After three-hour incubation, light microscopy examination revealed the highest manifestation of neutrophil apoptosis after induction by GLU (P<0.05). The lowest apoptosis manifestation, though statistically non-significant, was detected after induction by MDP and LPS. Determination of early manifestation of neutrophil apoptosis revealed the lowest manifestation of neutrophil apoptosis after induction by LPS (P<0.01). The results of late manifestation of neutrophil apoptosis revealed the highest proportion of apoptotic neutrophils after induction by GLU (P<0.05). The manifestation of secondary necrosis of apoptotic neutrophils or neutrophil lysis after 3 h of incubation was low and not significant. In conclusion, certain inducers of neutrophil migration into the lumen of bovine mammary glands (GLU and LPS in the present experiments) significantly influence the manifestation of neutrophil apoptosis during their subsequent in vitro incubation.

Animals↗
PubMed2003

Staphylococcus aureus isolates from dairy cows and humans on a farm differ in coagulase genotype.

Staphylococcus aureus is a frequent cause of animal and human infections. The aim of the present study was to test diversity of the populations of S. aureus colonising cattle and humans sharing an infected environment. Eighty-six S. aureus isolates obtained from dairy cows, from people coming into contact with dairy cows on the farm and the other farm personnel were characterized by restriction fragment length polymorphism of the coagulase gene. Molecular analyses identified ten polymorphism types with prevalent presentation of type II in isolates from cow's milk and type IV in isolates from people coming into contact with dairy cows on the farm (the cattlemen) and the other farm personnel. Seven further genotypes were identified among the isolates from the cattlemen. The results indicate that the strains dominating in human population did not equate to the causative agents of bovine mastitis.

Agriculture↗
PubMed2002

Prevalence of and resistance to anti-microbial drugs in selected microbial species isolated from bulk milk samples.

The prevalence of strains of Staphylococcus aureus, coagulase-negative (CN) staphylococci, Listeria monocytogenes, Escherichia coli, Enterococcus faecalis, E. faecium and Bacillus cereus, was investigated in 111 bulk milk samples. Staphylococcus aureus was isolated from 38 samples, CN staphylococci from 63 samples, E. coli from 49 samples, E. faecalis or E. faecium from 107 samples, and L. monocytogenes from two samples. Bacillus cereus was not found in any of the samples and three samples were free of any of the selected species. Sensitivity to the anti-microbial drugs amikacin, ampicillin, ampicillin + sulbactam, cephalothin (CLT), cephotaxime, clindamycin, chloramphenicol (CMP), co-trimoxazole, erythromycin (ERY), gentamicin, neomycin, norfloxacin, oxacillin, penicillin, streptomycin (STR), tetracycline (TTC) and vancomycin was tested using the standard dilution technique. Minimum inhibitory concentration (MIC) characteristics (MIC50, MIC90, MIC range) were determined for each microbial species. Resistance against one or more anti-microbial drugs was found in 93% of S. aureus, 40% of CN staphylococci, 73% of E. coli, 88% of E.faecalis, 55% of E.faecium, and one L. monocytogenes strain. Most of the strains, particularly enterococci, were resistant to STR, TTC, and ERY (MIC50 4 microg/ml). A high percentage of staphylococci were resistant to beta-lactam antibiotics. High resistance to CLT was found in 11 strains of E. coli (MIC 256 microg/ml) and strains resistant to CMP (MIC90 16 microg/ml) were detected. The highest numbers of resistance phenotypes were found in E. coil (16) and CN staphylococci (12). Eighteen identical resistance phenotypes were demonstrated in indicator bacteria (E. coli, E. faecalis, E. faecium) and pathogens (S. aureus, CN staphylococci) isolated from the same bulk milk sample. The obtained resistance data were matched against the herd owners' information on therapeutic use of the drugs. This confrontation could not explain the findings of strains resistant to ERY or CMP. Our findings are evidence of selection of resistant strains among not only pathogenic agents, but also among indicator bacteria which can become significant carriers of transmissible resistance genes.

Animals↗
PubMed2001

Comparison of methods for the determination of antimicrobial resistance in Staphylococcus aureus from bovine mastitis.

The results of three standard methods (broth dilution, agar dilution, disk diffusion) and an experimental modification of the microdilution method for determination of resistance to ampicillin, cephalotin, cloxacillin, neomycin, novobiocin, penicillin and streptomycin were compared using 151 Staphylococcus aureus isolates obtained from cases of mastitis. The accuracy of the dilution methods was compared by determination of minimum inhibition concentrations (MIC, MIC50, MIC90 and modal MIC) and by assessment of the agreement within the tolerance of +/-1 dilution step in 2-fold dilution series. The results of the dilution methods were further compared with those of the reference disk diffusion method and the strains were classified as sensitive or resistant using the interpretation criteria for human strains. The comparisons indicated that MIC characteristics and the final classification as sensitive or resistant were method-dependent. Resistance to aminoglycoside antibiotics was observed more often when using broth dilution methods, especially when the broth was supplemented with lactose.

Ampicillin↗
PubMed2001

Neutrophil apoptosis during the resolution of bovine mammary gland injury.

The role of neutrophil apoptosis in the resolution of bovine mammary gland injury induced by intramammary administration of physiological buffered saline (PBS) or lipopolysaccharide (LPS) was investigated. Twenty mammary glands of five non-pregnant heifers were used in the two studies and each animal received both stimuli. Samples of cell populations were collected by mammary gland lavages before and 24, 48, 72 and 96 hours after treatment and examined by light microscopy and staining for myeloperoxidase (MPO). A marked influx of neutrophils into the mammary gland was observed 24 hours after stimulation. At the same time, apoptotic neutrophils and MPO-positive macrophages (MAC) were identified in the samples. The numbers increased to reach maximum values at 48 hours after stimulation with PBS and at 72 hours after stimulation with LPS. The observed differences in the length of the resolution period indicate that neutrophil viability can be modulated by delaying the apoptotic process. Apoptosis of neutrophils and their subsequent phagocytosis by MAC can be regarded as a significant mechanism in the removal of neutrophils from the acutely injured mammary glands and, hence, in the resolution of bovine mastitis.

Animals↗
PubMed2001

Variations among unbred heifers in the activities of polymorphonuclear leucocytes from the mammary gland and blood.

The phenotypic characteristics are described for the activity of polymorphonuclear leucocytes NMN) obtained by either lavage of the cavity system of juvenile mammary glands stimulated with a synthetic muramyl dipeptide analogue or isolation from the peripheral blood. Attention was paid to the variability of characteristics and its sources, and to correlations among them. The following characteristics were investigated in 27 clinically healthy, unbred Bohemian Red Pied x Holstein heifers: migration activity in situ, number of phagocytosing PMN, phagocytotic index, bactericidal activity of PMN and unstimulated and zymosan-stimulated luminol-dependent chemiluminescence. Considerable individual variation was found in the characteristics. Significant differences between blood PMN and PMN from lavages after influx induction were found for bactericidal activity (P < 0.05) and chemiluminescence (P < 0.01). A significant correlation between blood PMN and mammary gland PMN was found only for the number of phagocytosing cells (r = 0.329; P < 0.01). Highly significant positive correlations (P < 0.01) were demonstrated between the number of phagocytosing PMN [a], phagocytotic index [b], and bactericidal activity [c] in both blood PMN (r(ab) = 0.602; r(ac) = 0.565; r(bc) = 0.529) and mammary gland PMN (r(ab) = 0.730, r(ac) = 0.618, r(bc) = 0.589). No significant correlation was demonstrated for non-stimulated (NS), zymosan-stimulated (ZS), or opsonized zymosan-stimulated (OZS) chemiluminescence with any of the other characteristics of phagocytotic activity, in either blood PMN or mammary gland PMN (P > 0.05). The animal was a highly significant source of variability for all the phagocytotic activity characteristics (P < 0.01). Udder quarter was a non-significant source of variability for all the characteristics of phagocytotic activity except for NS chemiluminescence (P < 0.05) and ZS or OZS chemiluminescence (P < 0.01). However, udder quarter was a non-significant source of variability of chemiluminescence indices ZS/NS and OZS/NS (P > 0.05). It has been demonstrated that in situ migration activity, the number of phagocytosing PMN, phagocytotic index, bactericidal activity of PMN and chemiluminescence indices of PMN collected from juvenile mammary glands of unbred heifers after influx induction can be regarded as candidate early markers of resistance to mammary infections.

Animals↗
PubMed1999

Ultrastructure of phagocytes from mammary glands of non-pregnant heifers.

Results of ultramicroscopic investigations of phagocytes isolated from non-secreting and aberrantly secreting juvenile mammary glands of non-pregnant heifers are presented. The two types of phagocytes observed in cell suspensions obtained by lavage of mammary gland cavities were polymorphonuclear leukocytes and macrophages. Polymorphonuclear leukocytes were spherical or irregular in shape and contained segmented nuclei. Azurophilic and specific electron-dense granules, mitochondria, glycogen particles, phagosomes and phagolysosomes in cytoplasma and characteristic pseudopodia on the cell surface were observed. In addition to these normal polymorphonuclear leukocytes, degenerating cells, characterized by spherical nuclei, total absence of pseudopodia, merged nuclear segments and altered granules, other cellular organelles and plasmalemma were present. Two types of macrophages, i.e. vacuolized and non-vacuolized, could be distinguished. Typical of the non-vacuolized type was a kidney-shaped nucleus, a rich Golgi complex and a large amount of lysosomes in the cytoplasm. The vacuolized macrophages contained a large amount of electron-dense vacuoles in the cytoplasm. Unlike non-secreting glands, the cell suspensions collected from aberrantly secreting juvenile mammary glands contained only vacuolized macrophages. The vacuolization results from phagocytosis of corpuscular particles of aberrant milk plasma.

Animals↗
PubMed1994

Minimal inhibition concentrations of selected antibiotics for strains of Staphylococcus aureus.

Minimal inhibition concentrations (MIC) of gentamycin (Ge), neomycin (Neo), rifampicin (Rif), ampicillin (Amp), lincomycin (Lin), erythromycin (Ery), and streptomycin (STM) were determined by the agar dilution technique using 46, 130, 131, 125, 140, 139 and 142 strains of Staphylococcus aureus, respectively. The strains, selected from the collection of the authors' laboratory, were isolated from mammary gland secretions of cows affected with clinical or subclinical mastitis. The following ranges of MIC (micrograms/ml) were assessed for the antibiotics under study: Ge 0.125-0.50, Neo 0.06-0.50, Rif 0.0039-0.030, Amp 0.015-1.00, Lin 0.25-1.00, Ery 0.06-0.25, STM 0.50-64.0. Modal MIC (micrograms/ml) were as follows; Ery 0.125 (86%), Lin 0.5 (71.4%), Rif 0.007 (68.7%), Ge 0.25 (56.5%), STM 1.00 (54.2%), Neo 0.25 (53.8%), Amp 0.06 (41.6%). The order of efficiency expressed in MIC 90 (micrograms/ml) was as follows: Rif (0.015), Ery (0.125), Ge (0.25), Neo (0.25), Amp (0.5), STM (4.0).

Animals↗
PubMed1993

[Effectiveness of the BR-Test and the Intest in the determination of chemotherapeutic residues in raw and preserved milk].

Negative detection of residues of inhibitory substances has become one of the standard quality traits of raw milk also in the Czech Republic. Hence a requirement appeared in 1991 to evaluate the usability of two commercially produced microtitration tests for this purpose. The tests of BR-TEST (Enterotox) and INTEST (Mlékárenský průmysl) were performed in weekly intervals for the time longer by a week than is the declared expiration, that means seven replications in BR-TEST and five replications in INTEST. Compact and stripped microplates (STRIPS) designated BR-TEST "AS", BR-TEST 12x8 "AS" and INTEST C-96 type and INTEST 0-96/6x16 were used for the tests. The principle of inhibition demonstration in the concentration series of selected drugs was applied. The drugs were chosen with respect to the frequency of their use for clinical treatments in the CR. Tab. II shows the used drugs and concentration series. The following parameters were tested: detection limits, reproducibility, effect of milk preservation, and the declared expiration. Tab. III shows detection limits. It is apparent the BR-TEST detection responses to streptomycin and chloramphenicol were lower in BR-TEST than in INTEST in our experiments. The responses to penicillin, oxacillin and oxytetracycline were lower in some cases, and equal in other ones. On the other hand, the INTEST detection response to sulfadimidin was markedly lower in comparison with BR-TEST. Tab. IV summarizes the range of detection limits in milk with Heeschen's reagent. In our experiments the detection response of BR-TEST to the tested chemotherapeutics was lower in some cases, in other cases it was the same as in INTEST.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

[Determination of protein A in Staphylococcus aureus strains from a collection].

The author used the haemagglutination method to estimate A protein in 153 strains of Staphylococcus aureus from collections. Protein A was detected in 66% of coagulase positive strains deposited in the course of time in the collection in 1983-1988. All strains were kept in skimmed milk at -20 degrees C. For evaluation of the reaction a semiquantitative scale was proposed. The author observed a diminished capacity to form protein A with the time of storage of the strains. In strains deposited for a shorter time in the collection (only three years) the percentage of positive results rose to 92.5%. In coagulase negative strains protein A was not detected.

Hemagglutination Tests↗
PubMed1990

[Algorithms in the evaluation of electrical conductivity in milk in screening for mastitis].

An algorithm of evaluation of diagnostic data for electronic screening of subclinical and clinical mastitis was derived from 5848 field measurements of the electric conductivity of mammary gland secretions and from the same number of clinical, bacteriological and cytological examinations of 92 dairy cows. The algorithm consists in the calculation of arithmetical mean of the two highest values of mixed, i.e. absolute, and or differential conductivity of a seven-day sliding cycle. Regardless of the intensity of disease forms, for healthy and colonized mammary glands, for mammary glands suffering from nonspecific subclinical mastitis, infectious subclinical mastitis and infectious clinical mastitis, the overall agreement with findings according to repeated clinical, bacteriological and cytological examinations made 88.8% with 4.2% of falsely negative and 7.0% of falsely positive findings. The overall agreement for persistent forms of diseases made 95.3% without falsely negative findings and with 4.7% of falsely positive findings.

Animals↗
PubMed1984

[Analysis of factors affecting the electric conductivity of cow's milk--breed, locale, season].

The problem was studied in a set of 678 mammary glands of 212 cows - crossbreds between the Holstein-Friesian breed with the Slovak Spotted cattle, crossbreds of the Black-Pied Lowland and Bohemian Spotted breed, and three-way crossbreds of the Black-Pied Lowland, Swedish White and Bohemian Spotted cattle. The confrontation of the confidence intervals of milk conductivity (MC) in healthy mammary glands at alpha = 0.05 showed that in the crossbreds of the Black-Pied Lowland cattle the MC was statistically significantly higher than in the breed types of the Holstein-Friesian cattle. The MC values decrease when there is a larger proportion of the blood of beef-and-dairy cattle (Slovak Spotted and Bohemian Spotted breeds). The locality where the stock was kept was found to act as an important factor underlying MC only in cases when both the geographical conditions and breed proportions were different. In a set homogenized with respect to the breeds, statistically significant differences in MC were demonstrated between the spring and summer season, spring and autumn, summer and autumn, and autumn and winter season.

Animals↗
PubMed1984

[The congruence and repeatability of electronic determinations of somatic cell counts in milk by diagnostic laboratories].

Six joint trials were conducted in six diagnostic laboratories equipped with the Coulter Counter Model D electronic computers. The congruence and repeatability of the determination of somatic cell counts in milk were determined in these trials. The results were confronted with similar trials performed in the Netherlands. The average differences in the results of determinations performed in the different laboratories exhibited a tendency of improvement as the joint tests proceeded, so that a satisfactory congruence of the results in all laboratories was obtained in the last trial. The standard deviation of the average difference and the average difference between parallel samples were characterized by high variedness . As found, the calibration of the computers by the plateau-and-trough method is not satisfactory and should be replaced by the calibration method of half the number and by the setting of an equal threshold size of the counted cells. The repeatability of determination will have to be improved by controlling rationing devices for milk dilution and by controlling the standard volumes counted by the apparatuses.

Animals↗
PubMed1984

[Relation of the count of somatic cells in tank samples to the incidence of contagious mastitis on large farms].

The relation between the prevalence of contagious mastitis with the finding of Streptococcus agalactiae and Staphylococcus aureus and the number of somatic cells in the tank samples of milk was studied on the basis of a clinical and bacteriological examination of 11 129 daily cows on four large farms, with a capacity of 600 to 1240 animals. A statistically significant correlation was demonstrated between the analyzed characteristics (r = 0.621). The relation was demonstrated at a prevalence up to 25.3%. The number of somatic cells provides a marked indication of prevalence only from 10%. We failed to demonstrate a statistically significant correlation between the prevalence of mastitis with a cultivation finding of Staphylococcus aureus and the number of somatic cells in tank samples of milk (r = 0.054). The results suggest that on large farms it will not be possible to use only the number of somatic cells in tank milk samples as a signal of diagnostic improvement and preventive mastitis-control measures, since a 10% prevalence of these diseases usually excludes the possibility of herd sanitation.

Animals↗
PubMed1980

[The diagnostic value of measuring the electric conductivity of milk].

A positive correlation of the milk specific conductance (MSC) to the number of cells (r = 0.65) and to the content of chloride ions (r = 0.93) was found on the basis of an examination of 196 udder-quarter milk samples. As indicated by the closeness of the relationship to the number of cells, MSC measurement at a determination level of 41.8% has similar diagnostic effectiveness as the determination of the content of chloride ions (determination level 43.5%) and lactose content (determination level 42.8%), and much higher diagnostic effectiveness than the determination of titration acidity (determination level 23.4%). As indicated by the closeness of the relationship to the content of chloride ions, MSC measurement at a determination level of 86.7% has higher diagnostic effectiveness than the determination of lactose content (determination level 73.9%) and titration acidity (determination level 54.6%). In both comparisons, the highest diagnostic effectiveness was found in assessing the chlorine-sugar number (determination levels of 49.8% and 94.0%). The MSC value, corresponding to the cellulization of 500 . 10(3) cells per ml of milk, was determined from regression: 0.523 S . m-1. The diagnostic congruence of MSC with the number of cells in milk was 81.25%, and with the findings of mastitis test-NK only 54.0%. The variability of the measurements of MSC renders it impossible to use this measurement to indirect multi-step screening of milk cellulization. It is only realistic to distinguish two classes of the measured MSC values: negative and positive.

Animals↗
PubMed1976

[Milking without additional hand stripping and health status of the mammary gland].

A field trial was performed in two half-sib first-calver groups of the Bohemiam Spotted breed. Each group included thirteen animals, studied for the effect of milking without additional hand stripping on the health condition of the mammary gland for a period of one lactation. The indices of an udder health condition were not affected at an appreciable level of statistical significance (the clinical and bacteriological picture, the positivity of the Mastitis test - NK, the content of milk cellular elements, milk chloride ion content, lactose content, and the value of the chlorine-sugar number. The unstripped udder halves showed a slight increase of the irritation index (by 0.1), milk cellular element content (by 33 000 per per 1 ml), chloride ion content (by 0.81 mmol 1+-1), and chlorine-sugar number (by 0.03). However, the mentioned increase did not exceed the limits of the physiological ranges of the parameters under study - hence it cannot be treated as a sign of udder alteration due to milking without additional hand stripping.

Animals↗
PubMed1975

[Influence of some factors on the electric conductivity of mixed milk].

The authors evaluated the method of the determination of the electric conductivity of purchased milk for the estimation of the hygienic aspects of mlik quality and for mass diagnosis of the inflammatory diseases of dairy cow mammary glands. The variability coefficient of duplicates varied from 1.37 to 3.09%. The study of the dependence of milk conductivity measurement on milk temperature revealed a statistically highly significant positive correlation between the values of these two factors. In the temperature range from 30 degrees C to 35 degrees C the coefficients of correlation ranged from 0.951 to 0.996. Furthermore, interference caused by milk acidity was examined during a five-day incubation of samples at 25 degrees C. A statistically significant difference was observed from the third hour of incubation (P less than 0.05) and a statistically highly significant difference from the fourth hour of incubation (P less than 0.01). the evaluation of the diagnostic value of the method of the measurement of electric conductivity in purchased milk revealed a positive correlation to the content of chloride ions (r = 0.69) and to the number of the cellular elements of milk (r = 0.33).

Acids↗