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P Butaye

Publications and source records attributed to P Butaye.

29 records · Page 2Linked to original sources

Phenotypic distinction in Enterococcus faecium and Enterococcus faecalis strains between susceptibility and resistance to growth-enhancing antibiotics.

Susceptibility of Enterococcus faecium and Enterococcus faecalis strains from animals and foods to growth-promoting antibiotics used in animal feed was tested by the agar dilution technique. Acquired resistance to bacitracin, narasin, tylosin, and virginiamycin was seen for both species, and for E. faecium, resistance to avilamycin and avoparcin was also seen. Drawing the distinction between susceptibility and resistance based on frequency distributions of MICs was easy with avoparcin, avilamycin, and tylosin but difficult with virginiamycin and to some extent also with bacitracin and narasin.

Animals↗

Comparison of glycopeptide-resistant Enterococcus faecium isolates and glycopeptide resistance genes of human and animal origins.

One hundred thirty-two glycopeptide-resistant Enterococcus faecium (GREF) isolates from different hospitals and pig and poultry farms in Belgium were compared on the basis of (i) their antibiotic susceptibilities, (ii) their SmaI pulsed-field gel electrophoresis (PFGE) patterns, and (iii) the organization of their Tn1546 or related elements in order to detect possible phenotypic and genotypic relationships among both groups of isolates. Human and animal vanA-positive GREF isolates were found to have similar susceptibility patterns; they remained susceptible to gentamicin and were, in general, susceptible to ampicillin. PFGE demonstrated a very high degree of genomic heterogeneity in both groups of isolates. However, indistinguishable isolates were found within different farms or hospitals, and in two instances, epidemiologically unrelated pig and human isolates showed indistinguishable PFGE patterns. In total, eight different transposon types were identified, and all were related to the prototype transposon Tn1546. The two predominant types, Tn1546 and type 2 transposons, which differed at three band positions, were present in both human and animal isolates. Type 2 transposons were significantly associated with pig isolates. The other types were seldom detected. These data suggest a possible exchange of glycopeptide resistance markers between animals and humans.

Animals↗

Identification of nonlipophilic corynebacteria isolated from dairy cows with mastitis.

Nonlipophilic corynebacteria associated with clinical and subclinical mastitis in dairy cows were found to belong to four species: Corynebacterium amycolatum, Corynebacterium ulcerans, Corynebacterium pseudotuberculosis, and Corynebacterium minutissimum. These species may easily be confused. However, clear-cut differences between C. ulcerans and C. pseudotuberculosis were found in their acid production from maltotriose and ethylene glycol, susceptibility to vibriostatic agent O129, and alkaline phosphatase. Absence of growth at 20 degrees C and lack of alpha-glucosidase and 4MU-alpha-D-glycoside hydrolysis activity differentiated C. amycolatum from C. pseudotuberculosis and C. ulcerans. The mastitis C. pseudotuberculosis strains differed from the biovar equi and ovis reference strains and from caprine field strains in their colony morphologies and in their reduced inhibitory activity on staphylococcal beta-hemolysin. C. amycolatum was the most frequently isolated nonlipophilic corynebacterium.

Acids↗

Pharmacokinetics and efficacy of amoxycillin in the treatment of an experimental Streptococcus bovis infection in racing pigeons (Columba livia).

The pharmacokinetics of amoxycillin in pigeons (Columba livia) and the efficacy of amoxycillin treatment in pigeon streptococcosis, were investigated. After intravenous administration of 150 mg.kg-1 amoxycillin, the drug plasma concentration-time profile fitted an open two-compartment model. Amoxycillin was quickly cleared from the circulation with a mean half-life of 66 min and showed a distribution volume of 0.9 L.kg-1. The absolute oral bioavailability of amoxycillin was 50.1%. A 5-day drinking water treatment with amoxycillin (1500 mg.L-1, corresponding to 112.0 mg.kg-1.day-1 during day-light hours) significantly reduced the postinoculation morbidity in pigeons experimentally infected with Streptococcus bovis, compared to untreated infected controls.

Amoxicillin↗

Effects of different test conditions on MICs of food animal growth-promoting antibacterial agents for enterococci.

The influence of the addition of sheep blood to Mueller-Hinton II agar and the effects of aerobic incubation with or without CO2 and of anaerobic incubation were tested with bacitracin, tylosin, avoparcin, virginiamycin, avilamycin, narasin, and flavomycin on enterococci. The antibacterial activity of bambermycin (Flavomycin) was strongly inhibited by the addition of blood, except with the species Enterococcus faecium, Enterococcus mundtii, Enterococcus hirae, Enterococcus casseliflavus, and Enterococcus gallinarum, which were not susceptible to this antibiotic on blood-free medium. With all other antimicrobials except avoparcin and tylosin, the presence of blood resulted in MIC increases of 1 to 3 log2 differences. Incubation in aerobic or anaerobic atmospheres enriched with CO2 lowered the susceptibility of enterococci to tylosin and increased their susceptibility to avilamycin, narasin, and avoparcin. This effect was most pronounced in tests on blood-free media. Results of susceptibility tests incubated under anaerobiosis and in a CO2-enriched atmosphere did not differ. For all enterococcal species, the preferred conditions for testing the susceptibility are Mueller-Hinton II medium supplemented with blood and incubation in a CO2-enriched atmosphere. However, when only E. faecium and Enterococcus faecalis are being tested, Mueller-Hinton II medium without blood incubated aerobically gives satisfactory results.

Aerobiosis↗

The prevalence of Chlamydia psittaci infections in Belgian commercial turkey poults.

The prevalence of Chlamydia psittaci infections in Belgian commercial turkey poults was examined and a follow-up study of one Belgian turkey flock was performed. Sera were examined for the presence of anti-chlamydia antibodies by immunoblotting. Cloacal and conjunctival swab smears and lung impression smears were examined for the presence of chlamydial antigen using the IMAGEN Chlamydia immunofluorescence test. Anti-chlamydia antibodies were found in 90 of 100 sera collected at slaughter from turkeys raised during the summer of 1992. The following winter, 73 of 100 sera reacted positively. On all twenty farms examined during 1992, turkeys were positive for anti-chlamydial antibodies. During 1993, chlamydial antigen was detected in swabs from 20 of 40 slaughterhouse turkeys tested. Antigen was found more often in the cloaca than in the conjunctiva. Chlamydial antigen was detected in samples from each of the 4 farms examined. The follow-up study on a turkey farm, sampling the birds at weekly intervals from one week old until 12 weeks of age, revealed that chlamydial antigen and anti-chlamydial antibodies were present during the whole period. During 1994, chlamydial antigen was detected in 45 of 60 lungs from slaughterhouse turkeys from all of 6 farms. During 1995, chlamydial antigen was detected in 41 of 54 lungs of 6 week old commercial turkey poults. The results of the present study indicate that Chlamydia psittaci infections are highly prevalent amongst Belgian commercial turkey poults with apparently little seasonal or year-to-year variation and that turkeys can contract the infection at an early age.

Animals↗

Characterization of avian Chlamydia psittaci strains using omp1 restriction mapping and serovar-specific monoclonal antibodies.

In the present study, 60 avian Chlamydia psittaci isolates were characterized using restriction fragment length polymorphism as well as serovar-specific monoclonal antibodies, enabling a comparison between the two characterization methods. Sixty avian C. psittaci isolates were characterized by Alul restriction mapping of the major outer membrane protein gene omp1 obtained after amplification by the polymerase chain reaction. The 60 avian C. psittaci strains were also characterized using serovar-specific monoclonal antibodies in a microimmunofluorescence test. Digestion of 60 avian C. psittaci omp1 amplicons by Alul generated 5 of the 6 known distinct restriction patterns (A, B, D, E and F). Restriction pattern C was not observed. Serotyping revealed 4 avian C. psittaci serovars (A, B, C and D). None of the 60 isolates was typed as serovar E. AluI restriction patterns A, B, D and E corresponded in 98% of the cases to serovars A, B, C and D, respectively. One isolate, classified as serovar A, generated restriction pattern F instead of A. Genotyping enabled a more precise differentiation of avian C. psittaci serovar A strains. Serovar A strains were divided into two groups according to their Alul restriction pattern (A or F). For epidemiological studies, genotyping can thus be a highly valuable alternative to serotyping, especially when applied directly to the clinical samples.

Animals↗