Prevalence of MRSA types in slaughter pigs in different German abattoirs.

To investigate the prevalence of types of meticillin-resistant Staphylococcus aureus (MRSA) in slaughter pigs in German abattoirs, nasal swabs were collected from a total of 1026 pigs in five abattoirs after stunning in the course of two studies, and examined for MRSA. Study 1 included four abattoirs; study 2 was carried out in one large abattoir. Isolates were tested for antimicrobial susceptibility and characterised using spa-typing, multilocus sequence typing (MLST) and typing of the staphylococcal cassette chromosome, SCCmec. Overall, MRSA was isolated from 70.8 per cent of 520 samples in study 1 and from 49.0 per cent of 506 samples in study 2. The proportion of positive samples varied substantially between the abattoirs in study 1. Most isolates belonged to spa-types t011 and t034 and SCCmec types III and V. MLST of selected isolates revealed that they were all MLST ST398. Besides beta-lactams, 100 per cent of the isolates were resistant to tetracycline, 80.5 per cent were resistant to erythromycin and 80.7 per cent were resistant to clindamycin. Less than 5 per cent of the isolates were resistant to other antimicrobials.

The isolation and identification of Leptospira interrogans serovar bratislava from a pig in Germany.

During a study on the improvement of selective media for the isolation of leptospires from clinical material, leptospires were isolated from the kidneys of a pig. Test material was cultured in EMJH-medium containing 0.4% rabbit serum and 3 inhibitory substances (Rifampicin 10 micrograms/ml, Amphotericin B 2 micrograms/ml, 5-Fluorouracil 100 micrograms/ml). The cultured leptospira-strain (Berlin 406) was identified to serogroup level using the cross agglutination method and it was further typed to serovar level by MAB's, factor analysis and restriction endonuclease analysis (REA). MAB typing of Berlin 406 gave an agglutination pattern profile typical of serovar bratislava. Factor serum identification clearly identified this strain as serovar bratislava. On REA examination, Berlin 406 gave a profile identical to that of the serovar bratislava type strain Jez Bratislava i.e. genotype B1. This is the first report of a confirmed isolate of Leptospira interrogans serovar bratislava from domestic animals in Germany. There exist a number of possibly important implications as this agent is being incriminated in the cause of clinical disease not only in pigs, but also in horses and dogs in other countries.

Serological reactions of leptospirosis-positive (MAR and CFT) bovine sera in ELISA.

The collection of test sera for measuring ELISA results was composed of bovine sera with MAT titres of greater than or equal to 1:200 in the leptospirosis MAT and of greater than or equal to 1:5 in the CFT together with sera from a serologically negative and clinically non-suspicious cattle herd. To establish cut-off ODs, the geometric mean net-extinction of the negative serum collection plus 1, 2, and 3 standard deviations were calculated. By comparison of 3 different conjugates from rabbits, it was demonstrated that results from anti-total bovine Ig were superior to anti-IgG and anti-IgM conjugates. Considerations regarding sensitivity and specificity led to the recommendation to use a test serum dilution of 1:160, to apply anti-total bovine Ig conjugates, and to establish the cut-off OD at the geometric mean net-extinction of negative sera plus 3 standard deviations. Under such conditions, agreement between leptospirosis MAT/CFT positivity on the one side and ELISA positivity on the other was reached in 74%. This recommendation is made for cross-sectional studies but not for examinations of clinically suspicious cattle herds.

[Udder immunization for the protection of calves from salmonella infections. 2. Estimation of serological findings of colostrum with regard to its protective activity]. / Euter-Immunisierung zum Schutz des Kalbes gegenüber Salmonella-Infektionen. 2. Beurteilung serologischer Befunde des Kolostrums hinsichtlich dessen Schutzwirkung.

Colostrum from cows which had been mammary gland vaccinated against salmonellosis were tested for antibodies by four different serological tests. Results from these tests were related to the protective activity for artificially infected calves. In opposition to agglutinating antibodies and antibodies detected by ELISA, complement fixing antibodies of the IgG1 class were shown to transfer early protection in artificially infected calves.

[Udder immunization for the protection of calves against salmonella infections. 1. Detection of specific Ig classes in the mother, colostrum and calf and the course of infection]. / Euter-Immunisierung zum Schutz des Kalbes gegenüber Salmonella-Infektionen. 1. Nachweis spezifischer Ig-Klassen im Muttertier, Kolostrum und Kalb sowie Verlauf der Infektion.

Pregnant cows were vaccinated at ablactation by infusion of heat inactivated S. dublin or S. typhimurium into the mammary gland in order to protect their offsprings via colostrum against salmonellosis. This method of vaccination is based upon statements according to which specific IgA and IgM play a prominent role in respect of protection. Both Ig classes are produced locally and are not channelled from the mother's system into the mammary gland. In comparison to calves from non-vaccinated control animals, calves from vaccinated cows did not exhibit clinical symptoms after challenge infection, and had a reduced salmonella excretion rate in respect of quantity but not in respect of the duration of shedding salmonella. Serological quantitation of specific Ig-classes (DIG-ELISA) did not allow to identify a specific Ig-class responsible for protection.

Species identification of blood-meals from tsetse flies (Glossinidae): results 1979-1985.

Results from species identification of almost 6,000 tsetse fly blood-meals are reported. Regarding Glossina palpalis and G. pallidipes, it was shown that the preference of tsetse flies for certain host species differed according to the sampling area. Consequently, results from blood-meal identification are to be interpreted with this point in view.

Use of formaldehyde-PBS for serum dilution in the microscopic agglutination test (MAT) for leptospirosis.

Altogether, 431 sera (381 positive and 50 negative sera) were tested against different Leptospira serovars in the microscopic agglutination test (CMAT) using PBS with and without formaldehyde for comparative purposes. For the preparation of serum dilutions with formaldehyde-PBS, formaldehyde was added to PBS at a final concentration of 0.4%. When retested after storage, 234 from the 381 formerly positive sera gave positive, 68 doubtful and 79 negative results in the MAT. Out of the 234 sera with positive reaction in MAT, 212 (90.6%) showed positive reactions in the MAT with formaldehyde as well, 19 (8.1%) doubtful reactions and 3 (1.3%) became negative. All sera with negative reaction in the routine MAT were found to be negative in the MAT with formaldehyde as well.