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261.
OBJECTIVE: To determine the frequency of urinary tract infections (UTIs) in dogs with indwelling urinary catheters in an intensive care unit (ICU) and the frequency of multi-drug-resistant (MDR) Escherichia coli UTIs in those dogs. DESIGN: Prospective study. ANIMALS: All dogs in the ICU with an indwelling urinary catheter from January 2003 through December 2003. PROCEDURES: Urine samples and rectal swab specimens were collected at admission and every 3 days until discharge from the hospital. Escherichia coli isolates from urine samples and rectal swab specimens and those from dogs that were temporally or spatially associated with dogs with MDR E coli UTIs underwent antimicrobial susceptibility testing. Pulsed-field gel electrophoresis was performed on MDR isolates from urine and rectal swab specimens. RESULTS: Urinary catheters were placed in 137 dogs. Twenty-six UTIs were diagnosed, 15 on the day of admission and 11 after 3 or more days of catheterization. Of 12 dogs with E coli UTIs, 6 were infected at admission and 6 acquired the infection in the ICU. Two MDR E coli UTIs were detected, 1 of which was acquired in the ICU. One MDR E coli urinary isolate had an electrophoresis pattern similar to that of rectal isolates from the same dog. Urinary E coli isolates were most frequently resistant to ampicillin and cephalothin. CONCLUSIONS AND CLINICAL RELEVANCE: The ICU-acquired MDR E coli UTI likely originated from the dog's intestinal flora during hospitalization. Dogs that have been referred from a community practice may have MDR E coli UTIs at the time of admission.  相似文献   
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OBJECTIVE: To describe MRSA infection and colonization in household pets, and transmission of MRSA between animals and humans. METHODS: MRSA infection and colonization in household pets and human contacts were evaluated during investigations initiated after identification of MRSA infection or colonization of a household pet in order to determine if there had been transmission between animals and humans. All MRSA isolates were screened for Panton-Valentine leukocidin (PVL) genes by use of polymerase chain reaction, and isolate relatedness was determined by use of pulsed-field gel electrophoresis (PFGE). RESULTS: Investigations of six situations where MRSA was identified in one or more animals in a household or veterinary facility were performed. MRSA was isolated from 8 animals (5 dogs and 3 cats) with clinical infections, 1 cat that was in contact with 2 infected cats and 14/88 (16%) of household contacts or veterinary personnel. Both animal-to-human and human-to-animal transmission were suspected. An indistinguishable MRSA isolate was recovered from at least one human that was in contact with each animal case. All isolates were classified as Canadian epidemic MRSA-2, the predominant community-associated MRSA clone in humans in Canada. No isolates possessed genes encoding for the PVL. CONCLUSIONS: Transmission of MRSA between humans and animals, in both directions, was suspected. MRSA appears to be an emerging veterinary and zoonotic pathogen.  相似文献   
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Concern has been raised about the potential for Clostridium difficile to be a bovine and foodborne pathogen, yet limited study has been performed in cattle, and none in veal calves. This study evaluated the epidemiology and microbiology of C. difficile on one veal farm. Rectal swabs were obtained from calves within 48 h of arrival and at one, 17 and 21 weeks later. Selective culture for C. difficile was performed. Isolates were characterized by PCR ribotyping and PCR for tcdA, tcdB and cdtA. Tetracycline resistance and resistance genes were investigated. Multivariable logistic regression models were constructed to determine the relationship between shedding of the bacterium and specific ribotypes and the independent variables: time of sampling and area of housing. Calves were twice more likely to test positive 1 week after arrival (51%) when compared to initial results (32%). Shedding at 17 and 21 weeks was significantly lower (2% at both samplings). Ribotype 078 was the most common. Twelve different ribotypes were present initially with only three ribotypes found subsequently. Seventy-six percent (40/53) of isolates initially recovered were tetracycline resistant compared to 93% (81/87) from 2nd sampling. Tetracycline resistance genes were detected in 24% (13/53) of isolates during 1st and in 55% (50/91) during 2nd sampling. The high prevalence of pathogenic C. difficile in veal calves could be of zoonotic concern. The low prevalence before slaughter may be of importance for the evaluation of foodborne risks. Oxytetracycline administration to calves may have an impact on prevalence of C. difficile colonization.  相似文献   
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AIM: To develop a real-time PCR for the detection of Mycoplasma agalactiae, using PCR primers targeting the ma-mp81 gene.

METHODS: A group of 15 M. agalactiae isolates, 21 other Mycoplasma spp. isolates and 21 other bacterial isolates was used in evaluation of the assay.

RESULTS: All M. agalactiae isolates were detected by the assay and none of the non-target isolates was amplified. The analytical detection limit of the assay was 10 fg of purified genomic DNA and 104 cfu/ml milk inoculated with M. agalactiae. When applied to goat-milk samples collected from three herds free of M. agalactiae infection, the assay had a specificity of 100%.

CONCLUSIONS: The assay would be useful in a diagnostic laboratory, providing specific, sensitive and rapid detection of M. agalactiae.  相似文献   
268.
Exudative epidermitis (EE) is a common skin disease of young pigs, caused mainly by Staphylococcus hyicus. Increased prevalence of EE and poor response to treatment are reported. Common strategies used by Ontario pork producers to treat pigs with EE were determined using a survey. Injection of penicillin G was reported as the most common parenteral antibiotic choice. Antimicrobial resistance patterns of S. hyicus and Staphylococcus aureus isolated from clinical cases (30 herds with samples from approximately 6 pigs per farm) showed that 97% of S. hyicus isolates were resistant to penicillin G and ampicillin; 71% of these isolates were resistant to ceftiofur. Similar resistance was noted among S. aureus isolates. Antimicrobial resistance has become a problem in the treatment of EE in Ontario.  相似文献   
269.
CASE HISTORY: A 6-year-old intact male New Zealand Huntaway dog had slowly progressive alopecia that was first observed at 12 weeks of age.

CLINICAL FINDINGS: Patchy alopecia was confined to the black-haired areas of the body, and was most evident on the head and dorsum of the body; tan-haired areas of skin appeared normal. Histological examination of black-haired skin revealed distended melanocytes and large aggregates of melanin within, and surrounding, the hair follicles and the epidermis. Macrophages distended with melanin were also visible within the perifollicular and superficial dermis, and follicular lumina were often plugged by keratin that contained aggregates of melanin. The follicles were dysplastic and few hair shafts were visible emerging from follicular infundibula within the sections.

DIAGNOSIS: The clinical and histological findings were consistent with black-hair follicular dysplasia (BHFD).

CLINICAL RELEVANCE: This is the first report of BHFD in a dog in New Zealand, and is the first report in a Huntaway. The most significant effect of BHFD is a predisposition to follicular plugging and secondary bacterial skin infections. Due to the hereditary nature of the follicular dysplasias, breeding from affected dogs should be discouraged. Histological examination of the skin is required to differentiate between the different follicular dysplasias as well as differentiating between follicular dysplasia and follicular atrophy due to endocrinopathy.  相似文献   
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