Vaginal isolation of beta-haemolytic Streptococcus from bitches with and without neonatal deaths in the litters.

The aim of the study was to identify beta-haemolytic streptococci in the vagina of bitches who had delivered healthy litters and bitches who had delivered litters in which neonatal deaths occurred. Fifty-one bitches divided into two groups were used. Group 1 (G1) included 28 bitches that had delivered healthy litters and group 2 (G2) included 23 bitches that had delivered puppies who died in the neonatal period. Two vaginal samples were taken, one in proestrus and the other at the end of gestation (EG). Beta-haemolytic Streptococcus (BS) was isolated from 16 bitches (57%) in G1 and from 21 bitches (91%) in G2. The bacteriological cultures, serological tests (Streptex® ) and PCR assay allowed identification of Streptococcus canis and Streptococcus dysgalactiae in G1 and G2. Ultramicroscopic studies allowed the observation of M Protein and capsules in strains of S. dysgalactiae and S. canis in G1 and G2. The S. canis strains isolated from G2 showed thicker capsules than S. canis strains isolated from G1 (234 ± 24.2 vs 151.23 ± 28.93 nm; p < .001.). No differences were observed in capsule thickness between strains of S. dysgalactiae isolated from G1 and G2 (210 ± 13.54 vs 211.66 ± 19.67 nm; p > .70). All strains of beta-haemolytic Streptococcus isolated were penicillin sensitive. Penicillin was administered from EG to 5 days post-partum in 10 G2 females with isolation of BS (G2A). Saline solution was administered in eleven G2 females with isolation of BS (G2B). Ninety per cent of the puppies survived in G2A and 25% survived in G2B. Our results suggest BS is involved in canine neonatal deaths.

[Antimicrobial resistance in indicator and zoonotic bacteria isolated from domestic animals in Argentina]. / Resistencia a los antimicrobianos en bacterias indicadoras y zoonóticas aisladas de animales domésticos en Argentina.

Antimicrobial resistance profiles in indicator and zoonotic bacteria isolated from faeces of healthy animals without clinical signs of the following species: bovine, equine, ovine, porcine, layer hens, and canine, were studied. The chosen antimicrobials are frequently used in veterinary and human medicine. The agar diffusion was the method used. The obtained results of 240 Escherichia coli, 189 Enterococcus spp., 11 Campylobacter spp. and 2 Salmonella Gaminara (16:d:1,7) showed a greater percentage of resistance and multiresistance in intensive breeding animals, porcine and layer hens. The observed resistance to ampicillin, streptomycin, tetracycline and nalidixic acid in E. coli coincides with the antimicrobials most commonly used on animal farms, the same as tetracycline and erythromycin in Enterococcus spp. The strains of Salmonella Gaminara (16:d:1,7) were susceptible to the antimicrobials tested. In Campylobacter spp. the scarce number of isolates hindered an adequate interpretation of the results. Owing to the lack of data in our country on antimicrobial resistance in indicator and zoonotic bacteria in domestic animals, we consider that the obtained values could be used as a starting point for a future monitoring program.

[Serovars of Salmonella enterica subspecies enterica and its antimicrobial resistance in slaughterhouse pigs]. / Serovariedades de Salmonella enterica subespecie enterica en porcinos de faena y su resistencia a los antimicrobianos.

A study was carried out in order to determine the prevalence of Salmonella and its serovars among porcine slaughterhouses, to evaluate the antimicrobial resistance profiles and to know the presence of class 1 integrons as possible reservoir of resistance. From a total of 386 samples from four porcine slaughterhouses of Buenos Aires and Santa Fe Provinces (Argentina), 93 (24.1%) Salmonella enterica subspecies enterica strains were identified, 52 (55.9%) from cecal contents and 41 (44.1%) from ileocecal lymph nodes. Thirteen serovars of S. enterica were found, the most prevalent were: S. Schwarzengrund, S. Heidelberg, S. subspecie I 6,8:e,h:-, S. Derby and S. Bredeney. Fifteen antimicrobials by the agar dilution method were tested: amikacin, gentamicin, ciprofloxacin, cephalotin, cefotaxime, enrofloxacin, fosfomycin, polimixin-B, tetracycline, chloramphenicol, streptomycin, trimethoprim-sulfamethoxazole, ampicillin, nitrofurantoin, and nalidixic acid. According to the CIM determination, 73% Salmonella enterica subspecies enterica strains were sensible to all the antimicrobials tested. Antimicrobial resistance was observed to tetracycline in 24 (25.8%) of 93 strains, to chloramphenicol in 22 (23.7%), to streptomycin in 22 (23.7%), to trimethoprim-sulfamethoxazole in 20 (21.5%), to ampicillin in 18 (19.4%), to nitrofurantoin in 3 (3.2%) and to nalidixic acid in 3 (3.2%). Some isolates of S. Typhimurium, S. Heidelberg, S. Derby, S. Orion showed multidrug resistance and carried the class 1 integrase gene. The highest percentage of resistance corresponded to the antimicrobials currently used in veterinary and porcine farms.

Serovariedades de Salmonella enterica subespecie enterica en porcinos de faena y su resistencia a los antimicrobianos / Serovars of Salmonella enterica subspecies enterica and its antimicrobial resistance in slaughterhouse pigs

Se realizó un estudio para determinar la prevalencia de Salmonella y sus serovariedades en cerdos de faena, para evaluar sus perfiles de resistencia a los antimicrobianos y para conocer la presencia de integrones de clase 1 como posibles reservorios de resistencia. A partir de un total de 386 muestras de porcinos provenientes de cuatro frigoríficos de las provincias de Buenos Aires y de Santa Fe (Argentina), se identificaron 93 (24,1%) cepas de Salmonella enterica subespecie enterica, 52 (55,9%) de contenido cecal y 41 (44,1%) de nódulo linfático ileocecal. Se hallaron 13 serovariedades de S. enterica, las más prevalentes fueron S. Schwarzengrund, S. Heidelberg, S. subespecie I 6,8:e,h:-, S. Derby y S. Bredeney. Se probaron 15 antimicrobianos por el método de dilución en agar: amikacina, gentamicina, ciprofloxacina, cefalotina, cefotaxima, enrofloxacina, fosfomicina, polimixina-B, tetraciclina, cloranfenicol, estreptomicina, trimetoprima-sulfametoxazol, ampicilina, nitrofurantoína y ácido nalidíxico. Según se estableció mediante la determinación de la CIM, el 73% de las cepas de S. enterica subespecie enterica fueron sensibles a todos los antimicrobianos probados. Se observó resistencia a tetraciclina en 24 (25,8%) de las 93 cepas, a cloranfenicol en 22 (23,7%), a estreptomicina en 22 (23,7%) a trimetoprima-sulfametoxazol en 20 (21,5%), a ampicilina en 18 (19,4%), a nitrofurantoína en 3 (3,2%) y a ácido nalidíxico en 3 (3,2%). Algunos aislamientos de S. Typhimurium, S. Heildelberg, S. Derby y S. Orion presentaron multirresistencia y portaban el gen de la integrasa clase 1. Los mayores porcentajes de resistencia correspondieron a los antimicrobianos habitualmente utilizados en veterinaria y en las explotaciones porcinas.

A study was carried out in order to determine the prevalence of Salmonella and its serovars among porcine slaughterhouses, to evaluate the antimicrobial resistance profiles and to know the presence of class 1 integrons as possible reservoir of resistance. From a total of 386 samples from four porcine slaughterhouses of Buenos Aires and Santa Fe Provinces (Argentina), 93 (24,1%) Salmonella enterica subspecies enterica strains were identified, 52 (55,9%) from cecal contents and 41 (44,1%) from ileocecal lymph nodes. Thirteen serovars of S. enterica were found, the most prevalent were: S. Schwarzengrund, S. Heidelberg, S. subspecie I 6,8:e,h:-, S. Derby and S. Bredeney. Fifteen antimicrobials by the agar dilution method were tested: amikacin, gentamicin, ciprofloxacin, cephalotin, cefotaxime, enrofloxacin, fosfomycin, polimixin-B, tetracycline, chloramphenicol, streptomycin, trimethoprim-sulfamethoxazole, ampicillin, nitrofurantoin, and nalidixic acid. According to the CIM determination, 73% Salmonella enterica subspecies enterica strains were sensible to all the antimicrobials tested. Antimicrobial resistance was observed to tetracycline in 24 (25,8%) of 93 strains, to chloramphenicol in 22 (23,7%), to streptomycin in 22 (23,7%), to trimethoprim-sulfamethoxazole in 20 (21,5%), to ampicillin in 18 (19,4%), to nitrofurantoin in 3 (3,2%) and to nalidixic acid in 3 (3,2%). Some isolates of S. Typhimurium, S. Heidelberg, S. Derby, S. Orion showed multidrug resistance and carried the class 1 integrase gene. The highest percentage of resistance corresponded to the antimicrobials currently used in veterinary and porcine farms.

[Antimicrobial resistance of Escherichia coli isolated from pigs in Argentina]. / Resistencia a los antimicrobianos de aislamientos de Escherichia coli obtenidos de cerdos de la República Argentina.

Antimicrobial resistance of Escherichia coil isolated from pigs in Argentina. Sixty-nine Escherichia coli isolates from healthy pigs or with clinical signs non-compatible with diarrhea caused by this microorganism, were studied. The purpose was to determine the resistance profile against antimicrobials frequently used in veterinary and human medicine. The agar diffusion method was used. High resistance percentages against antimicrobials used in swine farms such as ampicillin, streptomycin and tetracycline were observed, as well as against trimetoprim-sulfametoxazole and chloramphenicol, compounds that were stopped being used several years ago. Sixty two percent of isolates showed multidrug-resistance. The results obtained in this work corroborate the hypothesis that the phenotypic distribution of resistance and possibly that of its genetic determinants, are directly influenced by the antimicrobial treatments used.

[PCR-RFLP for Campylobacter jejuni subtyping]. / Aplicación de PCR-RFLP para subtipificar Campylobacter jejuni.

Ten Campylobacter jejuni isolates, 8 identified as C. jejuni biotype II of Lior and 2 as C. jejuni biotipe I, were recovered from aborted pig fetuses. In order to discriminate among strains, restriction fragment length polymorphism (RFLP) using Ddel of polymerase chain reaction (PCR) products of flaA gen was used. C. jejuni biotype II strains could be diferenciated in 6 by PCR-RFLP, and one subtype was obtained from C. jejunibiotype I. Although there is great variability of molecular techniques applied to the Campylobacter epidemiological studies, PCR-RFLP demonstrated to be a simple and accessible technique to discriminate Campylobacter jejuni isolates.

Aplicación de PCR-RFLP para subtipificar Campylobacter jejuni / [PCR-RFLP for Campylobacter jejuni subtyping]

Ten Campylobacter jejuni isolates, 8 identified as C. jejuni biotype II of Lior and 2 as C. jejuni biotipe I, were recovered from aborted pig fetuses. In order to discriminate among strains, restriction fragment length polymorphism (RFLP) using Ddel of polymerase chain reaction (PCR) products of flaA gen was used. C. jejuni biotype II strains could be diferenciated in 6 by PCR-RFLP, and one subtype was obtained from C. jejunibiotype I. Although there is great variability of molecular techniques applied to the Campylobacter epidemiological studies, PCR-RFLP demonstrated to be a simple and accessible technique to discriminate Campylobacter jejuni isolates.

Aplicación de PCR-RFLP para subtipificar Campylobacter jejuni. / [PCR-RFLP for Campylobacter jejuni subtyping]

Ten Campylobacter jejuni isolates, 8 identified as C. jejuni biotype II of Lior and 2 as C. jejuni biotipe I, were recovered from aborted pig fetuses. In order to discriminate among strains, restriction fragment length polymorphism (RFLP) using Ddel of polymerase chain reaction (PCR) products of flaA gen was used. C. jejuni biotype II strains could be diferenciated in 6 by PCR-RFLP, and one subtype was obtained from C. jejunibiotype I. Although there is great variability of molecular techniques applied to the Campylobacter epidemiological studies, PCR-RFLP demonstrated to be a simple and accessible technique to discriminate Campylobacter jejuni isolates.

[Campylobacteriosis in a low-income community in Buenos Aires, Argentina]. / Campilobacteriosis en una comunidad de bajos recursos de Buenos Aires, Argentina.

The authors describe the problem of campylobacteriosis in a low-income community located in southern Buenos Aires. Homes in the area were classified according to their total number of inhabitants, the number of children and animals living in the house and the amount of poultry meat consumed. Samples were taken from all the different types of homes that had been identified in order to isolate, identify and type Campylobacter sp., using the modified Skirrow technique, bio-chemical tests and the Lior technique respectively. The prevalences found were 16.96% in dogs, 20% in cats and 40% in poultry. The pathogens isolated were Campylobacter jejuni type II in 94.44% of the cases and Campylobacter upsaliensis in 5.55% of the cases. In poultry meat, 92.85% of the samples were positive (23.07% for type I and 76.92% for type II). The incidence of diarrhoea in children caused by C. jejuni was 0.4/1000 children/month (type I in all cases). A high prevalence of C. jejuni type II was detected in pets and in poultry meat. The source of infection in children may have been poultry meat.

In vitro antibiotic susceptibility of field isolates of Mycoplasma synoviae in Argentina.

Minimum inhibitory concentrations (MICs) were determined in vitro for 7 antibiotics (aivlosin, enrofloxacine, tylosin, tiamulin, kitasamycin, chlortetracycline, and oxytetracycline) against eight recent local Argentinean isolates and two standard strains of Mycoplasma synoviae. Aivlosin (3-acetyl-4"-isovaleryl tylosin tartrate), tylosin, and tiamulin showed the lowest MICs with MIC90s of 0.006, 0.012, and 0.05 microg/ml, respectively. Except one strain that showed resistant values to chlortetracycline (> or = 12.5 microg/ml), all the analyzed strains were susceptible in different degrees to all the antibiotics tested. In this study, the improved activity of the tylosin-derived drug, aivlosin, was confirmed because it showed, in most strains, MIC values half those for tylosin.

[Campylobacter jejuni and C. coli in aborted swine: comparison between phenotypic identification and polyacrylamide gel protein profiles]. / Campylobacter jejuni y C. coli en suinos abortados: comparación entre la identificación fenotípica y los perfiles proteicos en geles de poliacrilamida.

Campylobacter jejuni and Campylobacter coli were isolated from aborted pig fetuses which proceeded from different animals and farms between February 2000 and March 2001. Seven Campylobacter jejuni biotype II, three biotype I and one Campylobacter coli biotype I were identified by phenotypic tests and Lior's scheme. To corroborate and compare the phenotypic results, 7.5, 10 and 12.5% polyacrilamide gel electrophoresis (SDS-PAGE) were used under reducing conditions. Characteristic bands of hypervariable dense zone within C. jejuni and C. coli species were observed in all the whole cell protein extracts with differences in mobility. It was possible to establish differences between identical phenotypic Campylobacter isolates and different protein profile from fetuses of the same litter. SDS-PAGE is a stable and reproducible method to establish differences between Campylobacter strains and is considered applicable for the differentiation of the wide variability of Campylobacter species for epidemiologic purposes.

Campylobacter jejuni y C. coli en suinos abortados: comparación entre la identificación fenotípica y los perfiles proteicos en geles de poliacrilamida / [Campylobacter jejuni and C. coli in aborted swine: comparison between phenotypic identification and polyacrylamide gel protein profiles]

Campylobacter jejuni and Campylobacter coli were isolated from aborted pig fetuses which proceeded from different animals and farms between February 2000 and March 2001. Seven Campylobacter jejuni biotype II, three biotype I and one Campylobacter coli biotype I were identified by phenotypic tests and Lior’s scheme. To corroborate and compare the phenotypic results, 7.5, 10 and 12.5

polyacrilamide gel electrophoresis (SDS-PAGE) were used under reducing conditions. Characteristic bands of hypervariable dense zone within C. jejuni and C. coli species were observed in all the whole cell protein extracts with differences in mobility. It was possible to establish differences between identical phenotypic Campylobacter isolates and different protein profile from fetuses of the same litter. SDS-PAGE is a stable and reproducible method to establish differences between Campylobacter strains and is considered applicable for the differentiation of the wide variability of Campylobacter species for epidemiologic purposes.

Campylobacter jejuni y C. coli en suinos abortados: comparación entre la identificación fenotípica y los perfiles proteicos en geles de poliacrilamida. / [Campylobacter jejuni and C. coli in aborted swine: comparison between phenotypic identification and polyacrylamide gel protein profiles]

Campylobacter jejuni and Campylobacter coli were isolated from aborted pig fetuses which proceeded from different animals and farms between February 2000 and March 2001. Seven Campylobacter jejuni biotype II, three biotype I and one Campylobacter coli biotype I were identified by phenotypic tests and Liors scheme. To corroborate and compare the phenotypic results, 7.5, 10 and 12.5

polyacrilamide gel electrophoresis (SDS-PAGE) were used under reducing conditions. Characteristic bands of hypervariable dense zone within C. jejuni and C. coli species were observed in all the whole cell protein extracts with differences in mobility. It was possible to establish differences between identical phenotypic Campylobacter isolates and different protein profile from fetuses of the same litter. SDS-PAGE is a stable and reproducible method to establish differences between Campylobacter strains and is considered applicable for the differentiation of the wide variability of Campylobacter species for epidemiologic purposes.

[Serotyping of strains of Serpulina hyosenteriae isolated form swine with porcine dysentery symptoms in the province of Buenos Aires]. / Serotipificación de cepas de Serpulina hyodysenteriae aisladas de cerdos con cuadros de disentería porcina en la Provincia de Buenos Aires.

Seventeen Serpulina hyodysenteriae strains isolated from faeces, rectal swabs and intestinal contents of pigs with Swine Dysentery, from farms located in Buenos Aires province were serotyped. Samples on selective media (trypticase soy agar added by 5% ovine blood, 400 mg/l spectinomicin, 30 mg/l colistin, 30 mg/l vancomycin) were streaked and incubated under anaerobic atmosphere for 72 h at 42 degrees C. Suspected S. hyodysenteriae growth were identified by strong beta-hemolytic zone, without colonies, and the spirillar morphology, using the Victoria Blue 4-R stain were criteria following by S. hyodysenteriae preliminar identification. The following antigens were made by phenolic extraction from a concentrated inocula washed twice in PBS pH 7: whole-cell (WC), boiled cell (BC) and lipopolysaccharide (LPS). Two serological test were: coagglutination and immunodiffusion, using polyclonal rabbit antisera against the 9 serotypes of S. hyodysenteriae and S. innocens, using WC and BC like antigens for the first test and BC and LPS for the second. The Dot-ELISA Test was performed using BC and LPS antigens and monoclonal antibodies (AbM) against serotypes 1, 2, 3, 8, 9 of S. hyodysenteriae, AbM species-specific and AbM against S. innocens. All isolated S. hyodysenteriae strains belonged to serotype 8. Like in other countries occurred, it would exit a high regional prevalence of S. hyodysenteriae serotype, being the serotype 8 in Argentine.

Comparison of fecal Campylobacter in calves and cattle of different ages and areas in Japan.

To define the species of Campylobacter harboring in the intestine of calves and adult cattle and to examine their distribution among different age groups and farms, 34 calves and 60 adult cattle raised in 6 farms in 3 different areas were studied. Campylobacters were detected in the feces obtained from healthy calves (97.1%) less than 1-year-old but were much less frequently found in adult cattle (46.7%). Young calves harbored more species of Campylobacter than adult cattle. The isolation rate of campylobacters in adult cattle differed depending upon the farms examined. C. jejuni, C. hyointestinalis and C. fetus subsp. fetus were isolated from 61.8, 26.5, and 26.5% of calves, respectively. However, these 3 species were detected at the lower rates of 11.7 to 15.0% in adult cattle. C. coli, C. lari, C. fetus subsp. venerialis, C. fecalis, and other Campylobacter spp. were also detected in a few calves and adults. These results indicate that campylobacter colonization in the intestine is very common in young calves but not in adult cattle.