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Objectives: This study was performed in cooperation with the State Veterinary Administration (SVA) in order to monitor the occurrence of Shiga toxin-producing Escherichia coli isolates in swabs from the carcasses of pigs and cattle at slaughterhouses., Material and Methods: From June to August 2013, SVA staff took 168 swabs from cattle and 318 from pigs at 157 different slaughters in the Czech Republic. Basic processing of the samples was carried out in the State Veterinary Institutes (SVIs) in Prague, Jihlava and Olomouc according to the methodical process coordinated by the National reference laboratory (NRL) for Escherichia coli (Czech Ministry of Agriculture). The procedure was based on the guideline ISO TS 13136., Results: Out of the 486 swabs, twenty-two positive samples were detected. There were a total of 22 isolates of Shiga toxigenic E. coli (STEC) and 1 strain with the characteristic of enterohemorrhagic E. coli (EHEC). Genes typical for enteroaggregative E. coli (EAggEC) were not found in any of the isolates. Most STEC strains originated from pigs. The stx1 gene was detected twice (stx1a, stx1d) and the stx2 gene 13 times (12 times stx2e, once stx2a). Seven STEC isolates were detected from samples of cattle origin. One strain was stx1 (stx1a) -positive, the stx2 gene was found 6 times (4 stx2e, 1 stx2a and 1 stx2c). One isolate carried simultaneously both stx1a and stx2a. Each of the serogroups O91, O113 and O146 described as etiological agents of severe disease in humans were detected only once. None of these strains harbored additional virulence factors typical for strains causing serious illness., Conclusion: RESULTS of this study show the overall prevalence of Shiga toxigenic E. coli of 4.5 % and 0.2 % of enterohemorrhagic strains in the studied samples. Raw meat originating from local farms does not currently represent an important source of STEC for humans.

Yeasts frequently colonize various kinds of domestic animals, but may also cause serious diseases. The aim of this study was to identify yeast isolates collected from dogs, cows and pigs, and to determine their in vitro antifungal susceptibility. Fifty-six yeast isolates from dogs (n = 24), cows (n = 20), and pigs (n = 12) were investigated. Appearance of colonies grown on Sabouraud agar, micromorphology on rice agar, as well as assimilation and fermentation of various carbon and nitrogen sources were evaluated. Susceptibility to six antifungals (flucytosine, amphotericin B, miconazole, ketoconazole, itraconazole and fluconazole) was determined semiquantitatively using the commercially available Fungitest kit (Bio-Rad Laboratories). Ten yeast species were identified in dogs with relatively even distribution. On the other hand, cow and pig were clearly dominated by Candida krusei (from 7 species) and Candida rugosa (from 5 species), respectively. Further, most of yeast isolates exhibited good susceptibility to the antifungals tested particularly to amphotericin B, ketoconazole and itraconazole. Based on results, it can be concluded that significant differences in the species spectrum and distribution were documented between groups of yeasts from dogs, cows and pigs. This is probably due to different environmental conditions and the endogenous origin of the yeast isolates. Mostly good susceptibility to systemic antifungals should positively influence the therapy of diseases caused by yeasts in veterinary medicine.

Virginiamycin is an antibiotic active against grampositive bacteria in the alimentary tract, which is also suitable for supplementation of diets of growing and finishing ruminants. The aim of this work was to specify the effect of virginiamycin on some parameters of rumen fermentation in vitro with inoculi taken from wethers adapted or non-adapted to the virginiamycin intake. Incubations were performed anaerobically at 39 degrees C in serum bottles closed with Bunsen valves. Virginiamycin was added at 0 or 10 mg/l to the rumen fluid diluted with McDougall buffer. Virginiamycin significantly decreased production and utilization of lactic acid, production of methane and decomposition of casein when rumen fluid was taken from non-adapted wethers. Most of its effects disappeared when rumen fluid was sampled from wethers adapted to the virginiamycin intake (100 mg per head daily for 2 months). Adaptation of wethers to virginiamycin was further confirmed by analyses of the rumen fluid which was used for inoculation of in vitro cultures. Molar percentages of acetate, propionate, butyrate and valerate were the same before and after the adaptation. Therefore it can be concluded that the effects of virginiamycin on rumen parameters are not stable and its addition to ruminant diets cannot be recommended, with exception of the milk nutrition period. In the last experiment the stability of virginiamycin in the rumen fluid of adapted wethers was investigated.(ABSTRACT TRUNCATED AT 250 WORDS)

The prevalence of antibodies to C. burnetii was studied in the Karlovy Vary district (the Czech Republic) between 1987 and 1989. Sera of cows, sheep and heart eluates of small ground mammals were tested using the complement fixation test with C. burnetii antigen in phase II (Bodibion, Mevak Nitra, Slovakia). Titers greater or equal to 8 or 10 were considered as positive. Cows from two large-scale farms were tested four times (the average number of every sampling was 339 cows). Their seroprevalences varied from 0.3 to 4.3% and from 0.3 to 10.6% on the first and second farm, respectively. The highest seroprevalences were on both farms in July, 1987. No clinical signs of Q-fever were observed in cows from these farms. In May, 1988, sera of 96 sheep from two farms were tested. No antibodies to C. burnetii were detected. A total of 488 small ground mammals from 9 various localities was tested. Antibodies were ascertained in one Common Vole (Microtus arvalis) at a titer of 10 and in one Bank Vole (Clethrionomys glareolus) at a titer of 2560. At present, some strains of C. burnetii occur in cattle and small ground mammals in the study area but these strains do not cause the clinical Q fever as they did in the same area at the beginning of the fifties.

Using the test of indirect immunofluorescence, the authors examined sera of animals for antibodies against the strain CG 18-20 of Hantavirus (identical with strain Puumala) and against the Hantaan strain. As a control and supplement of the examination the authors used cells containing the TBE virus, strain Hypr. In a group of 260 hares (Lepus europaeus) in 3.5% antibodies were present against Hantavirus CG 18-20. Of 41 deer (Capreolus capreolus) they were present in 14.1%. Of 11 fallow-deers none had antibodies against hantaviruses. Among 145 specimens of Bos taurus antibodies were present in two incl. one against the strain Hantaan. The findings are discussed in relation to previous research of natural foci of hantavirus infections and infections with the TBE virus in Bohemia and Moravia. The paper reveals hitherto unknown localities of foci and hitherto not studied participants of the circulation of hantaviruses.

The incidence of staphylococcus species in healthy animals was investigated in young and adult individuals of cattle, in pigs and in domestic fowl, using the method of selective isolation of strains. A total of 6066 samples was examined; 4567 strains were revealed and they included all known species, except Staphylococcus caseolyticus, S. saccharolyticus, S. schleiferi and S. lugdunensis. 3.8% of strains failed to be identified with any species. The test samples were taken from slaughtered animals, only in calves intravital smears of tonsils were examined. The species most frequently isolated from the tonsil tissue in adult cattle were as follows: S. aureus (19.9%), S. saprophyticus (12.4%), S. hyicus (8.8%) and S. hominis (8.6%). The following species were isolated from the lung tissue: S. saprophyticus (28.8%), S. cohnii (10.6%) and S. epidermidis (10.2%); from the mammary gland parenchyma these were the species S. saprophyticus (17.4%), S. xylosus (13.1%) and S. epidermidis (10%). In the tonsil tissue of pigs the percent proportions of S. aureus and S. hyicus were 44.5% and 31.8%, respectively; the most frequent species detected from the lungs were S. aureus (20.6%), S. saprophyticus (12.3%), S. hyicus (12.1%) and S. epidermidis (11.5%). In domestic fowl the most frequently occurring species were S. epidermidis (23.7%), S. gallinarum (16.5%) and S. aureus (15.4%). In calves the incidence of S. xylosus (37%), S. saprophyticus (19.2%) and S. cohnii (15.2%) was found to be highest. The indicence of the other staphylococcus species in all test animals can be expressed by low percentages.

In 65 stable strains of K. pneumoniae, nine of which originated from acute parenchymatous mastitis of cattle and 56 from milk, nasal mucus, skin from the udder base and from the rectal contents of clinically healthy dairy cows, the virulence for white mice was studied. The achieved results were as follows: (1) At 1 ml dose of the 24-hr. broth culture i. p., 51 strains (78.4%) were virulent, at 2 ml dose 56 strains (86.1%). The percentage of the strains from milk and from the rectal contents of the clinically healthy dairy cows was approximately the same, whereas the strains from acute parenchymatous mastitis and skin were virulent in the full extent. (2) The influence of the growth phase and of the presence of microbial capsule was not marked because both in the capsuled and in the uncapsuled strains the lethal doses amounted to 0.2 to 2.0 ml, however, in both groups also the completely harmless strains were detected. In a detailed evaluation it is necessary to take into consideration that in the capsuled strains (49) the lethal doses amounted to 0.5 ml (50% of all cases) and in the uncapsuled to 1 ml (43.7% of all cases). (3) Necrotoxin test showed that 18 strains (27.7%) caused local skin inflammation in the rabbit, lasting 3 to 6 days and characterized by skin reddening and swelling (diameter 1.5 to 2.0 cm). This finding is in direct correlation with the death of experimental mice but not with the lethal doses and time of exitus; in both cases 0.2 to 2.0 ml doses were applied and the animals died one to three days after inoculation.

The microbial population of the praeputial sac was studied in a group of ten young bulls housed in one section of the rearing farm in the age period from 2 to 14 months when they were transferred to A. I. stations. As to currently occurring microflora, Proteus sp. and Pseudomonas aeruginosa were isolated most frequently. The remaining micro-organisms isolated during the study included E. coli, non-haemolytic and viridizing streptococci, Staphylococcus epidermidis, micrococci, aerobic sporulating bacteria, saprophytic corynebacteria snd gamma-negative non-fermenting rods. Campylobacter foetus subsp. foetus was not detected and the same applies to the other species of this genus (Campylobacter sp.). When the bullocks were transferred to the rearing farm, the mycoplasms were no longer isolated from the praeputial mucous membrane. Mycoplasms were determined in all the studied animals after six months' stay in group. The isolated strains were identified as M. bovigenitalium by the epiimmunofluorescence method.

A simplified scheme for the subdivision of coagulase-positive staphylococci and another simplified scheme for the diagnostics of coagulase-negative species were worked out. On the basis of the production of staphylokinase, coagulation of human and bovine plasma, acetoin production from glucose, and growth on agar with crystal violet, it is possible to identify S. aureus with its biovars A, B, C1, C2, D, as well as S. intermedius. The coagulase-negative species can be diagnosed according to their sensitivity to novobiocin, nitrate reduction, fermentation of maltose, sucrose, salicin, xylose, trehalose, mannitol and mannose, and haemolytic activity. The proposed diagnostic schemes were verified with success on the collection strains and on the 1305 staphylococci strains isolated largely from the bovine mammary gland, from dogs, man and domestic fowl. In S. aureus strains a close correlation was demonstrated between their biotype characteristics and the host species. A similar correlation was determined for S. intermedius. As to the coagulase-negative species, S. epidermidis, S. hominis and S. haemolyticus were diagnosed most frequently. Both schemes represent a reliable, prompt and technically simple method of the diagnostics of the Staphylococcus microorganisms.