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Introduction: Fifty-six E. coli, 37 P. multocida und 8 M. haemolytica were isolated from 157 nasal swabs taken from calves in 52 dairy herds. The antibiotic susceptibility of the organisms was determined by measurement of the minimal inhibitory concentrations. Of the 56 E. coli isolates, 55.3% exhibited resistance to tetracyclines, 55.3% to sulfonamides, 39.3% to beta-lactams, 30.3% to aminoglycosides, 8.9% to fluorochinolones and 3.5% to 3rd generation cephalosporins. The 3rd generation cephalosporin- resistant isolates contained the extended spectrum-beta-lactamase gene blaCTX-M-14 and came from 2 farms where the milk of cows under antimicrobial treatment was fed to the calves and mastitis was treated with cefquinome as first line therapy. Of the 37 P. multocida isolates, 48.6% exhibited resistance to tetracyclines, 16.2% to beta-lactams, and 5.4% each to macrolides, aminoglycosides and sulfonamides. The 8 M. haemolytica isolates showed no resistances against the tested antibiotics.

The VIDAS Salmonella Test (VST) is an enzyme-linked fluorescent immunoassay for the detection of Salmonella-antigens. The suitability of VST for the detection of Salmonella in faecal, tissue, and feed samples was evaluated by the comparison with routine culture methods. From 312 naturally contaminated samples 17 were classified as Salmonella positive by routine methods and 28 by VST. Salmonella were isolated from 15 VST positive samples by the routine method and from eight samples only by an extended culture method. Five positive VST results could not be proved by culture. Two samples were classified as positive by the routine method and as false-negative by VST. The sensitivity varied between 88% and 100% and the specifity between 92% and 100%, depending on the kind of sample. Matrix or serovar specific factors resulting in a false VST result could not be determined. The performance of VST was easy and did not require special experiences. Mostly, samples with Salmonella negative results were faster detected than by culture methods. VST is suitable for the detection of Salmonella in the studied kind of samples especially as a screening method.

Two siblings of African origin presented with multiple scaling patches and alopecia on the scalp four weeks after returning from a vacation in Eritrea. Direct KOH examination revealed fungal elements; Trichophyton mentagrophytes and Trichophyton terrestre were identified in the fungal culture. We discuss the putative pathogenic role of both microorganisms in causing disease. Although infection with Microsporum canis currently accounts for almost fifty percent of all cases of tinea capitis in Germany, other fungi have gained importance due to tourism and increasing migration.

Probiotic feed additives have to undergo a strict assessment according to EU regula-tions, including the evaluation of the influence on the gut microflora of the host animal. A probiotic strain of the genus Enterococcus faecium and two different host animal species, young calves and newly hatched turkeys, were chosen as a test model for the establishment of schemes for feeding trials. Investigations included faeces samples and pooled swab samples of faeces as well as samples from gut sections derived from diagnostic slaughtering. The samples were tested for aerobic total count, for enterococci count and for Enterobacteriaceae and E. coli. The test schemes were appropriate for the evaluation of the influence of the probiotic feed additive on the physiological gut microflora of the host animals. Additional information could be gathered concerning safety aspects and effectiveness.

Protein patterns from 681 Pasteurella multocida strains of different animal species and distinct geographical regions were analyzed by PAGE. We found 9 protein types taking the most intense band as reference. This band represents a protein of the outer membrane (OMP). In assigning the strains to protein types a relation to animal hosts of the strains was established. The majority of isolates from rabbits (88%) belongs to type P6, which is not found in strains isolated from cattle or pigs. Strains from pigs did not include the protein types P2, P4 and P8, in cattle strains type P9 was absent. The distribution of protein types in bovine isolates was shown to be related to the geographical location. The results are discussed with particular emphasis on immuno-prophylaxis. It appears promising to develop P. m. vaccines specific for certain animal species.

Enterohemorrhagic Escherichia coli (EHEC) are increasingly identified as the cause of diarrhea and hemorrhagic colitis in countries with highly developed livestock. In 5-10% of patients, full-blown hemolytic uremic syndrome (HUS) occurs as a postinfectious life-threatening complication. Up to 1996, 5 out of 39 patients (12.8%) with EHEC O157 infections in Austria developed HUS. Acute complications of HUS such as brain edema may also lead to death; one fatal outcome has been observed so far in Austrian patients. Aside from the cytotoxic Shiga toxins, other different pathogenic factors are often found in clinical EHEC isolates. These include a cytolysin termed EHEC-hemolysin and a low molecular heat-stabile enterotoxin. Furthermore, most EHEC strains express an important surface protein, intimin, which is important for adherence to intestinal epithelial cells. EHEC are heterogeneous in their antigenic structure (O-, H-antigens). In Austria O157:H7 and O157:H- are the dominating serogroups; in 1997 the first Austrian case of HUS due to EHEC O26:H11 was documented. Because there are no known reliable phenotypical markers for EHEC, diagnostic strategies should focus on the demonstration of Shiga toxins or Shiga toxin genes. For epidemiological purposes it is also important to attempt to isolate the causative agent. Cows and other ruminants are reservoirs for EHEC. In the Tyrol 3% of unpasteurised milk samples, up to 10% of minced beef samples, and 6% of calves yield EHEC O157. Aside from transmission via contaminated food, direct transmission from person to person also plays a major role in the chain of EHEC infection. In contrast to Italy and Bavaria, Austria has not experienced a major outbreak due to this organism so far. A nationwide surveillance system of HUS has shown an incidence of 0.37 HUS cases per 100,000 residents in the age group 0-14 years for 1995 (Italy: 0.2 cases per 100,000; Bavaria: approx. 1.5 cases per 100,000).

In the context of the detection of the haemolyticuraemic syndrome (HUS) and of enterohaemorrhagic E. coli (EHEC) in 13 persons, 372 faeces samples from 13 herds of cattle in northern Bavaria were examined for the presence of EHEC. 128 (34.4%) of the faeces samples were found to be VT-positive. From 78 of these samples (61%), verotoxin-producing E. coli strains (VTEC) could be isolated. During these examinations, E. coli strains with combinations of markers (VT, eae A, EHEC haemolysin) being typical of EHEC were found in 3 samples from animals belonging to the same herd. In 2 cases, these could be assigned to O157:H-, in one, to O118:H16. It has not been possible to detect possible sources of infection and chains of infection assumed to exist in association with the detection of HUS and EHEC infections in humans because most cases had been diagnosed on the basis of verotoxin detection in stool specimens. Moreover, corresponding isolates for a comparative onward differentiation from verotoxin-producing E. coli isolates from animals were not or could not be made available.

In man, EHEC infections may result in severe disease. Cattle and foods derived from this animal species are considered as a source of infection. The presence of VTEC being potential EHEC was studied. For analysis, feces samples were examined which had been taken from 204 heads of cattle slaughtered in various regions of Germany. VTEC could be isolated from 97 animals (47.6%). This indicates a presence of VTEC in slaughtered cattle being 5 times higher than known for Germany so far. The aeaA gene could be demonstrated in a mere 23 out of 667 VTEC isolates. The CVD 419 sequence was present in 55.3% of the VTEC isolates. Ehly was found in 61% of them. Consequently, both markers were unsuitable for the detection of VTEC in faeces samples from cattle and in foods with faecal contamination. The VTEC isolates belonged to 54 different serotypes of E. coli, VTEC 0157 have not been found so far. Some of the VTEC serovars found in this study have already been described as associated with human disease following EHEC infection. The presently available laboratory methods do not permit to exclude a risk for humans from bovine VTEC reliably. For this reason, bovine VTEC should be further on considered as potential EHEC and an infection of humans by such agents be avoided.

A total of 383 Pasteurella strains isolated from calves and pigs were typed by their phenotypic properties and allotted to the following species and subspecies: [table: see text] P. multocida ssp. septica, P. avium biotype 2, P. canis and P. canis biotype 2 could be isolated up till now only from calves, on the other hand P. multocida ssp. gallicida were found in pigs only.

With the DNA-DNA colony hybridization technique using specific gene probes for Verotoxin 1 (VT 1) and Verotoxin 2 (VT 2) 2100 E. coli strains from healthy animals were tested. Ten out of 82 milk cows (21.2%), 20 out of 212 beef cattle (9.4%) and five out of 75 pigs (6.7%) were found to carry genes for VT 1, VT 2 or both toxins, respectively. Among these strains the biotypes 5 and 6 were predominant. Some of the serotyped isolates have been described to be pathogenic for humans, like O157:H7, 082:H8, 0116, 0113, 0126 and 091, respectively. The unexpected high incidence of VTEC positive healthy animals possibly indicates a health hazard for human beings. Further investigations on the incidence of VTEC in food are necessary.

Cultivation of Staphylococcus aureus in a fermenter significantly improved production of coagulase (Fig. 1,2,3). Optimal coagulase-activity was reached in the culture supernatant after inoculation with 8 x 10(9) colony-forming S. aureus per ml of brain heart infusion broth and 20 min at 37 degrees C. At this time most of the other enzymes and toxins (particularly protease and staphylokinase) had not been formed or only in small amounts. Characterization of coagulases from respectively 5 S. aureus-cultures from humans, cattle and dogs revealed molecular weights between 56800 and 71000, and isoelectric points between 5.4 and 6.4 (table 1).

In accordance with previous papers published within a series of publications which describe the results obtained from the Central Laboratory for Streptococcal Research in Kiel (1. Survey, 2. Mastitis-Streptococci) the group of Enterococci is discussed herewith. On the basis of more than 6000 strains which are stored in our databank including all biological characteristics, the distribution of the cultural, biochemical and serological parameters is listed in percentages, and the usefulness and reliability for the identification of the enterococcal group and also the differentiation of particular species is discussed. The results are tabulated for every single species and additionally, for serologic-positive and negative strains. For example, it can be shown that a third of all Str. faecium strains are motile, that lack of growth at 45 degrees C varies between 1.1% and 31.3% and that lack of serological reaction with group D-serum between 0.9% and 70%. In a comprehensive table and flow diagram these figures result in a proposal for a simple but sufficient identification procedure on different stages (enterococci, faecalis- or faecium-group, single species) depending on the individual requirements. With regard to the incidence of enterococci in man and animals, which was presented in the first paper, the organ sources of the different species are compared now. Apart from some interesting findings it can be stated that a typical predominance of the faecalis and faecium-group resp. in man or animals cannot be confirmed. But there seems to be a relation between the species and the organ source. For example, in humans the faecium-group predominates in the respiratory tract, but in the urogenital tract the presence of Str. faecalis is seven times higher than the faecium-group. The above results may also be of interest for ecological reasons and may be important for the pathogenesis and epidemiology of this streptococcal group.

The interrelation between the time of the withdrawal of rumen fluid and the DPA: N-relation in the fraction of mixed rumen bacteria was ascertained in a test with two cows with rumen fistulae. At the moment of feeding the DPA-content of 63 mg per g bacteria was very high. In the period of 3 to 9 hours after feeding it remained relatively constant (50 mg). A mean conversion relation of 20.4 of DPA to bacteria N was ascertained. The amino acid model proved to be the same in all fractions, the content values were comparable to those found in technical literature.

One single intravenous injection of 60 mg/kg of cyclophosphamide caused the development of moderate to medium catarrhal enteritis in calves, within two to four days from injection. --Distally aggravating damage to epithelial cells in the small intestine, accompanied by shortening of villi, as well as usually complete lymphocyte depletion of the lymph follicles of Peyer's patches were the most conspicuous pathohistological findings obtained from the intestinal tract. Regular epithelial damage, including ulcerations and necroses, were recordable also from the colonic mucous membrane. --No remarkable change in the gastro-intestinal flora was recordable from calves killed two days from cyclophosphamide application, but the quantitative composition of the gastro-intestinal germ flora was found to be remarkably altered in those animals which had been killed four days after administration of the cytostatic. --Elevated coli counts in the rumen as well as in the proximal and distal parts of the jejunum and ileum and reduced anaerobic overall germ counts and bacteroides values in the cecum and rectum were the most conspicuous bacteriological findings. --The direct damaging action of cyclophosphamide on the mucous membrane as well as altered immunological reactivity of the experimental animals should be considered the triggering factors which actually caused considerable displacement in the quantitative composition of the gastro-intestinal flora in those calves which had been killed four days after cyclophosphamide application.

Three cows were given two rations, a silage diet (3 animals) and a green forage diet (2 animals). Samples of rumen content were collected and aliquots of these were separated in a fraction of feed particles and protozoa (FP-fraction) and a fraction of mixed bacteria, varying the conditions of differential centrifugation. The low speed centrifugation was practised at 100 X g/5 min, 400 X g/10 min, 1000 X g/10 min, and 2000 X g/10 min. High speed conditions were 30,000 X g/30 min 4 degrees C. The lyophylisated sediments were used for determination of N and DAP. The content of N gave similar results for all fractions of mixed bacteria, the mean value being 7.43 +/- 0.48% (n = 20), while the N-content of the FP-fractions being 5.68 +/- 0.37% (n = 19). The N:DAP-ratio gave similar values for the cows fed the silage diet, the values were 29.45 +/- 1.56 (n = 12). The values for the cows receiving the green forage diet differed, the mean values were 23.08 +/- 0.88 and 42.01 +/- 5.81 (n = 5), respectively. In all five experiments highest ratios were found at 100 X g. Further investigations showed that storage at -20 degrees C rumen fluid after isolation of feed particles and protozoa decreased both the N- and DAP- content without affecting the N:DAP-ratio. Centrifugation at low speed with 100 X g resulted in a markedly decreased contamination with DAP in all the FP-fractions. Optimal conditions for separation of feed particles and protozoa from rumen fluid to get a fraction best reflecting the rumen bacterial populations are 100 X g/5 min.

Fecal samples of cattle and swine and samples of raw material and pulverized dehydrated meat taken from three rendering plants were investigated with special enrichment methods on the presence of Clostridium botulinum to get a view about the hygienic risk by the incidence of C. botulinum in rendering plants. Eight-six specimens were examined: 25 fecal specimens each of swine and cattle, 11 of raw material and 25 of pulverized dehydrated meat of three rendering plants. Twelve specimens contained C. botulinum: 7 fecal specimens, 6 of swine and one of cattle, 4 raw material specimens and one of pulverized dehydrated meat. C. botulinum was detected by its toxin production in culture medium. Six times C. botulinum type E, twice C. botulinum type B and one time C. botulinum type C was identified. C. botulinum could not be typed in other cases because the toxin quantities were too small. C. botulinum type E was detected in raw material and pulverized dehydrated meat in one of the three examined rendering plants.