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H U Bertschinger

Publications and source records attributed to H U Bertschinger.

At least 37 records · Page 2Linked to original sources

[Epidemiology of trichophytosis in fattening calves in regard to the prevention of leather defects].

During the year 1989 12,520 veal calves were visually examined for ringworm at the Zürich abattoir. The mean prevalence of ringworm amounted to 7.7% with a maximum of 12.8% in July and a minimum of 5.1% in March. Epidemiological data were collected at repeated visits from 73 calf fattening farms. Batches of calves were significantly more frequently affected in continuous management systems (51%) than in all-in all-out systems (28%). Ringworm was more prevalent in farms with large groups of calves, and where calves were shorn. Prevention of leather defects necessitates prophylactic measures. The latter are determined by the importance of animal to animal contacts for transmission of the fungus. The health status of calves at purchase and the choice of the management system are therefore of primary importance. Vaccination may be considered in problem herds. A premium for high quality skins might further stimulate the interest of the producers in leather quality.

Animals↗

Inheritance of resistance to oedema disease in the pig: experiments with an Escherichia coli strain expressing fimbriae 107.

Inheritance of resistance to intestinal colonization with E. coli causing oedema disease is hypothesized to be under the control of one locus consisting of two alleles with susceptibility (S) dominating resistance (s). This mode of inheritance was investigated by mating pigs, resistant and susceptible to the disease, and examining the offspring. Weaned piglets were repeatedly inoculated orally with 5 x 10(5) CFU per pig per day of a streptomycin resistant strain of E. coli serotype O139:K12(B):H1:F(107) and susceptibility determined by daily semiquantitative cultural examination of rectal swabs. Using results obtained from offspring, 5 boars were retrospectively assigned the genotype ss, 1 was assigned Ss, and 2 were assigned SS. Nine sows were designated ss, 8 classified Ss and 4 SS. Ninety two pigs resulted from matings regarded as ss x ss; 89 (97%) of these were resistant to colonization and oedema disease. Of the 168 pigs from Ss x ss matings, 83 (49%) were resistant, while only 13 (9%) of 146 pigs from matings with at least one SS parent were classified resistant. The results are compatible with inheritance being controlled by one locus and with susceptibility dominating resistance to oedema disease.

Amoxicillin↗

The role of adhesive F107 fimbriae and of SLT-IIv toxin in the pathogenesis of edema disease in pigs.

Colonization of the small intestine and the excretion of a toxin are important steps in the pathogenesis of edema disease in pigs. Although much is known about the chemical and biological characteristics of SLT-IIv toxin, its mode of action and its genetic determinant, F107 fimbriae were only recently described as colonization factors. Here we summarize our current knowledge about the virulence factors F107 fimbriae and SLT-IIv toxin.

Animals↗

Adhesive fimbriae produced in vivo by Escherichia coli O139:K12(B):H1 associated with enterotoxaemia in pigs.

Two strains of E. coli O139:K12 (B):H1 were compared in vitro and in the intestinal environment. Both strains colonized the small intestines of experimentally inoculated pigs and exhibited in vivo a similar relationship to the microvillus border as enterotoxigenic E. coli (ETEC). Strain 107/86 grown on blood agar expressed numerous long flexible non-haemagglutinating fimbriae which were antigenically distinct from the known fimbriae of porcine ETEC. It adhered in vitro to porcine enterocyte brush border fragments. Strain 124/76 grown on blood agar was devoid of fimbriae and did not adhere to brush border fragments. However, fimbriae morphologically and antigenically indistinguishable from those of strain 107/86 were detected in the intestinal environment by direct immunofluorescence and by immuno electron microscopy.

Animals↗

[Lowering of the incidence of puerperal mastitis in the sow by protection of the mammae from contamination].

Twelve sows each farrowed in an experimental pen designed especially for this study or in a crate. Viable counts of enterobacteriaceae were performed in samples taken from the laying area and from the teats. Secretion from every mammary complex was examined repeatedly for bacteria and for somatic cells. The sows in the experimental pen did not lay down in their own faeces. The viable counts in samples from the laying area and the teats were much lower than with the sows kept in farrowing crates. Infection with E. coli was observed in 3 mammary complexes of the sows in the experimental pen as compared to 27 complexes of the sows in the crate. More than half of the infections was detected in the samples taken before farrowing began. In the average the bacteria persisted for 1.3 days. On the first 4 days of life piglets sucking teats with cytologically defined mastitis had an average daily gain of 105 g as compared to 125 g with piglets sucking healthy teats. In conclusion puerperal mastitis is a consequence of faecal contamination of the mammary gland. Soiling of the laying area with faeces and urine can be reduced by improvements in the farrowing accommodations.

Animals↗

V-factor dependent strains of Pasteurella multocida subsp. multocida.

At bacteriological examination of swine lungs with pneumoniae due to Mycoplasma hyopneumoniae, two strains of pyridine nucleotide (V-factor) requiring bacteria were isolated. They exhibited a pattern of biochemical reactions fitting with that of Pasteurella multocida subsp. multocida. Deoxyribonucleic acid (DNA): DNA hybridization with these isolates and Pasteurella multocida subsp. multocida showed that they were V-factor requiring strains of this species. Preliminary investigations on the qualitative and quantitative V-factor requirements have been performed.

Animals↗

Ultrastructure of the intestinal mucosa in pigs experimentally inoculated with an edema disease-producing strain of Escherichia coli (0139:K12:H1).

The intestinal tissues from 11 pigs orally inoculated with Escherichia coli (E. coli, 0139:K12:H1) were examined by transmission electron microscopy. The colonization of E. coli along the small intestinal mucosa was found in seven principals without any major changes in the enterocytes from day 2 to day 7 after inoculation when the experiment was terminated. Lesions of vessels of the intestinal mucosa could be detected as early as two days after inoculation and persisted until the experiment was terminated. Lesions consisted of endothelial swelling and vacuolation, subendothelial fibrin deposition, perivascular edema, microthrombus formation, endothelial proliferation, and necrosis of the tunica media. The possible pathogenesis of the disease is discussed.

Adhesiveness↗

[How widespread is Q fever in Switzerland?].

There are very few reports in the literature on mass seroepidemiological studies of the prevalence of Q fever antibodies. Those to be found are mostly concerned with focal epidemics of Q fever. Out of more than 2000 serum specimens from blood donors analyzed at random in Switzerland in 1982 for Q fever antibodies, 3.5% gave seropositive results (CBR titer at least 1:10). In selected population samples, e.g. forestry workers or vets, the prevalence was distinctly higher (7.6% and 25.7%). Contact with sheep and the consumption of unboiled and not commercially processed milk proved to be mutually independent risk factors. The foregoing findings indicate that the incidence of Q fever in Switzerland is higher than would appear from the number of cases reported to the Federal Health Department. They are discussed in view of the recent renewed interest in Q fever endocarditis.

Animals↗

Bacterial colonization and morphology of the intestine in porcine Escherichia coli enterotoxemia (edema disease).

Twenty-one pigs were divided into three groups. Pigs in one group were inoculated with the intestinal contents which included bacteria from a pig with edema disease. Pigs in another group were inoculated with a culture of Escherichia coli serogroup O 139:K12(B):H1 isolated from the aforementioned contents, and pigs in a third group served as uninoculated controls. The infection was similar following both inocula. Enterotoxemia developed in 11 of the 14 pigs allowed to survive for more than two days. The onset varied from two to seven days after inoculation. There were maximal viable counts of E. coli in the intestine from the second day post-inoculation and thereafter. In frozen and paraffin sections, as well as by scanning electron microscopy, the organisms were seen on the surface of the small intestinal epithelium where they formed either isolated colonies or continuous layers. They colonized the lower small intestine more intensely than the upper section. The intestinal epithelium and the villi of infected pigs were indistinguishable morphologically from the tissues of three uninoculated control pigs. The diarrhea which was observed in controls and inoculated pigs before inoculation and the villus atrophy in controls and inoculated pigs indicated a preexisting infection with at least one other agent.

Animals↗

Role of nutrition in the pathogenesis of porcine Escherichia coli enterotoxaemia.

The role of nutrition in the pathogenesis of E. coli enterotoxaemia was studied in weaned pigs inoculated with a field strain of E. coli O139:K82(B):H 4. Feeds extremely low in nutrients (5% crude protein, 4.6 MJ/kg digestible energy, 17% crude fibre) completely prevented the disease by inhibiting proliferation of the pathogenic bacteria in the intestine. This protective effect of the diet could not be used for disease control, because the pigs did not develop immunity. A diet moderately low in nutrients (8% crude protein, 9 MJ/kg digestible energy, 11% crude fibre) allowed proliferation of the inoculated bacteria to the point, where most of the pigs developed solid immunity and losses were significantly reduced. This diet combined with inoculation of the pigs with herd specific organisms allowed control of the disease in the field.

Animal Feed↗

Quantitative detection of antibodies to Mycoplasma suipneumoniae in pigs' sera by an ezyme-linked immunosorbent assay.

A new method for quantitative detection of antibodies to Mycoplasma suipneumoniae in pigs' sera has been developed by the application of an enzyme-linked immunosorbent assay (ELISA). The results show that the ELISA is specific and highly sensitive. In experimentally infected pigs antibodies could be detected several weeks before the clinical manifestation of enzootic pneumonia.

Animals↗