Enterotoxin production by Staphylococcus species other than Staphylococcus aureus has been reported. Staphylococcus strains (104 in toto) representing twelve species and subspecies were examined for enterotoxins using a commercial staphylococcal enterotoxin ELISA immunoassay (TECRA, International Bioproducts). Staphylococcus intermedius (24 strains) and S. aureus (7 strains) were positive with this test. Western blots of S. aureus exoproteins demonstrated proteins of ∼30 kD, consistent with known staphylococcal enterotoxins. The major antigen in all S. intermedius strains, a 75 kD protein, was not analogous to previously described staphylococcal enterotoxins. This protein was unique to S. intermedius. Gel filtration data indicate that the protein is a subunit of a larger protein in vivo. The 75 kD protein cross-reacts with several enterotoxin antibodies. It is unclear whether the protein is a toxin, but its homology with S. aureus enterotoxins may indicate a shared toxic region, or this protein may create false positive results in screening for enterotoxin.

Successful treatment of canine pyoderma has become increasingly difficult due to the development of antimicrobial resistance and recurrence of infection. The development and spread of antimicrobial resistance has major implications because treatment failures have been associated with increased mortality, morbidity and costs related to disease. All canine skin samples submitted to Vetdiagnostix Veterinary Pathology Services for microbiological culture and sensitivity between January 2007 and June 2010, from which Staphylococcus intermedius was isolated, were selected for this investigation. A total of 319 samples from dogs of various ages, sexes and breeds from various locations throughout South Africa were obtained. In addition to the antimicrobial susceptibility data, data relating to dog signalment (age, gender, breed), case history and any other aspects of the history provided e.g. diagnosis, sample type and geographical location of the patient were collected. The number of skin samples yielding Staphylococcus intermedius was high in dogs up to the age of 6 years and, then decreased with only a few cases in dogs aged 11 years or older. The distribution of samples collected in 2010 was unusual in that there were two peaks, one in dogs two years old or less and one in 6 to 9-year-old dogs. With the exception of skin samples taken in 2008, a high percentage of dogs were under the age of one year old. 2008 had a lower percentage of affected dogs less than one year of age compared to the other years. Staphylococcal pyoderma is more common in dogs below the age of five years. Dogs above this age are less likely to contract this condition. The genders tended to be equally distributed throughout the years, with almost equal proportions of affected males and females present. The Bull Terrier types and Shepherd types were grouped separately as they were over-represented and are known to be prone to pyoderma. Large short haired dogs were consistently worse affected throughout the years sampled, followed by the Bull Terrier types. In 2010, small short haired breeds were worse affected compared to the numbers between 2007 and 2009. The monthly distribution, with the exception of 2009, tended to be consistent throughout the years. The unusual temporal distribution in 2009 could be associated with a general distribution in the number of samples compared to the other years sampled. Samples tended to be mainly from practices located in the KwaZulu-Natal province of South Africa. This is most likely due to the fact that the laboratory is located in this province, with a courier network that arranges collection from these practices. Practices in other regions send their samples to the laboratory via private courier companies and the South African Post Office. Antimicrobial resistance of S. intermedius was greatest to ampicillin followed by tetracycline and then potentiated sulphonamides. The results also showed that, in general, antimicrobial resistance was low. Very few methicillin resistant isolates were detected. Temporal trends were not noted, with the exception of ampicillin where isolates became more susceptible and potentiated sulphonamides (co-trimoxazole) where isolates were becoming more resistant. Staphylococcus intermedius is significantly less resistant to erythromycin, clindamycin, cephalexin, oxacillin, amoxicillin-clavulanic acid, enrofloxacin, marbofloxacin and gentamicin, with most strains being susceptible to these drugs. Resistance to penicillin and tetracycline is frequently found in Staphylococcus intermedius and is on the increase. Resistance to most other antimicrobials, particularly newer generation antimicrobial agents such as the fluoroquinolones, is still comparatively low. In general, both the Kirby-Bauer and broth dilution MIC tests yielded similar results for the antimicrobial agents tested. The main difference between the two tests was evident in the over-estimation of resistance by the Kirby-Bauer test in the cases of ampicillin, co-trimoxazole, penicillin and doxycycline. This could be related to the instability of these particular drugs in vitro. Inoculum densities may also have played a role, with denser inocula producing smaller zone sizes for the drugs tested. Using the MIC method, all of the isolates tested were found to be completely sensitive to ticarcillin, oxacillin, amoxicillinclavulanic acid, imipenem, ceftiofur, chloramphenicol, doxycycline, gentamicin, amikacin and co-trimoxazole. Of the isolates tested using the MIC method, between 2-40% showed some level of resistance to the following antimicrobials: erythromycin, penicillin, ampicillin, enrofloxacin, clindamycin and marbofloxacin. The highest level of resistance observed was shown to erythromycin. The increase in resistance to the lincosamides, lincomycin, clindamycin and erythromycin may be attributed to the increased use of these drugs in the last decade. Knowledge of trends in bacterial resistance is important for veterinarians when determining treatment for canine skin infections. The information obtained from the analysis of the antimicrobial susceptibility profiles of Staphylococcus intermedius isolated from canine pyoderma cases will provide veterinarians with valuable information on choosing the most appropriate drug to treat S. intermedius skin infections as well as re-enforcing the need for the prudent use of antimicrobial drugs in companion animals. Copyright / Dissertation (MSc)--University of Pretoria, 2011. / Veterinary Tropical Diseases / unrestricted

Numerous species of the genus Staphylococcus other than Staphylococcus aureus are important pathogens in human clinical practice and veterinary medicine. With improved methods of identification and more precise classification, we have speciated over 500 strains of staphylococci representing 17 species and subspecies of non-S. aureus Staphylococcus. We have examined these strains for possible virulence factors which may play a role in their pathogenesis. Using transmission electron microscopy (TEM), we have demonstrated that small to large amounts of glycocalyx are found on staphylococcal cells. Animal models have shown that staphylococci cause abscess formation in the presence or absence of a foreign body implant. Molecular characterization of cell extracts of Staphylococcus intermedius show that this species elaborates a protein which is serologically similar to the enterotoxins of Staphylococcus aureus in ELISA tests, but differs markedly in other characteristics.

The purpose of this study was to evaluate the antimicrobial potential of the propolis extract, natural substance known for its therapeutic properties, against to 67 microbial isolates of canine otitis. The Minimum Bactericidal Concentration (MBC) of the propolis extract against the isolates of coagulase-positive Staphylococcus and the Minimum Fungicide Concentration (CFM) for Malassezia sp. isolates were determined using the broth microdilution technique. The MBC was 15.1mg mL-1, while the MFC was 2.4mg mL-1. Thus was shown the antimicrobial potential of the propolis extract tested against these two agents and the lower bactericidal and fungicidal concentration needed for the inhibition of them. / O objetivo do presente estudo foi avaliar o potencial antimicrobiano do extrato de própolis, substância natural conhecida pelas suas propriedades terapêuticas, frente a 67 isolados microbianos da otite canina. A Concentração Bactericida Mínima (CBM), do extrato de própolis, frente a isolados de Staphylococcus coagulase positiva e a Concentração Fungicida Mínima (CFM) para isolados de Malassezia pachydermatis foram determinadas utilizando-se a técnica de microdiluição em caldo. A CBM foi de 15,1mg mL-1, enquanto a CFM foi de 2,4mg mL-1.Dessa forma foi demonstrado o potencial antimicrobiano do extrato de própolis testado contra esses dois agentes e a menor concentração bactericida e fungicida necessária para a inibição dos mesmos.

Memoria para optar al Título Profesional de Médico Veterinario / Staphylococcus spp, forman parte de la microbiota de piel y mucosas de caninos, pero son además patógenos oportunistas principalmente las especies S. intermedius y en menor medida S. schleiferi subesp. coagulans y S. aureus, produciendo pioderma y otitis externa. La terapia de este tipo de patologías por lo general es empírica y prolongada, pudiendo provocar resistencia antimicrobiana. El objetivo de este estudio fue caracterizar, a través de la detección de genes, las bases moleculares de resistencia a antimicrobianos como macrólidos (ermB), tetraciclinas (tetM), β-lactámicos (mecA) y detectar la mutación de los genes gyrA y grlA que determinan la resistencia a quinolonas. De un total de 170 cepas aisladas desde otitis externa (53) y pioderma (117), 1 cepa presentó resistencia fenotípica a oxacilina, 16 a tetraciclinas, 18 a macrólidos y 15 a quinolonas. La detección del gen mecA fue de un 100%, tetM un 81,25% (13) y ermB 94% (17). La mutación responsable de la resistencia en los genes gyrA y grlA fue detectada en el 100% de las cepas que se enviaron a secuenciar, encontrándose en la posición 84 en el caso de gyrA reemplazando el aminoácido serina por una leucina y en la posición 80 para grlA sustituyendo una serina por una isoleucina. Si bien la prevalencia de resistencia en Chile es aun menor en comparación a otros países, este es el primer estudio a nivel nacional que ayuda a conocer los mecanismos de resistencia en las bacterias de las mascotas, destacando además por primera vez en país, la presencia del gen mecA en Staphylococcus intermedius aislado de un canino / Proyecto MULT-O6/03-2

Memoria para optar al Título Profesional de Médico Veterinario / El presente trabajo corresponde a un estudio transversal que incluyó cepas de Staphylococcus spp. coagulasa positivo de gatos con diversas patologías dermatológicas atendidos en el Hospital Clínico Veterinario de la Universidad de Chile entre marzo a diciembre del año 2010. Se ingresaron 68 muestras de 68 pacientes con afecciones dermatológicas, obteniéndose 30 cepas (44%) de Staphylococcus spp. coagulasa positiva de 30 pacientes, las cuales se identificaron mediante el kit BBL Crystal TM para Gram positivas y se les realizó el estudio de sensibilidad antimicrobiana mediante el método de difusión en placa de Kirby-Bauer, según las normas de Clinical and Laboratory Standards Institute (CLSI, 2008). Los antimicrobianos en estudio fueron: oxacilina, amoxicilina con ácido clavulánico, ampicilina, clindamicina, eritromocina, cefadroxilo, doxiciclina, tetraciclina, sulfametoxazol-trimetoprim, vancomicina, ciprofloxacino y enrofloxacino. Staphylococcus intermedius fue la especie más frecuentemente aislada alcanzando el 67% (20 cepas), seguido por Staphylococcus aureus con un 33% (10 cepas). El 10% del total de cepas en estudio (3 cepas) fueron sensibles a todos los antimicrobianos utilizados, el 37% (11 cepas) fueron resistentes a un antimicrobiano y un 53% (16 cepas) fueron multirresistentes. El 13,3% del total de cepas (4 cepas) fueron resistentes a meticilina, siendo todas identificadas como S. intermedius, todas éstas fueron resistentes a fluoroquinolonas, lincosamidas, macrólidos y sulfonamidas. Ninguna cepa fue resistente a vancomicina / FIV 2009 Código: 12101401.9102.008