Change over time and agreement between clinical markers of disease resolution in dogs with aspiration-induced lung injury.

BACKGROUND: There is a lack of consensus regarding which markers of disease resolution to prioritise when assessing treatment response in client-owned dogs with aspiration-induced lung injury. This study describes the change over time and the agreement between the clinical markers used to determine disease resolution. METHODS: Physical examination (PE), owner-reported clinical signs (CS-O), thoracic radiographs (TXR) scores and C-reactive protein (CRP) concentrations were determined at enrolment, after 24, 48 and 72 hours, and after 7, 14 and 28 days. RESULTS: PE scores were significantly improved at 48 hours, while CRP initially increased (24 hours) and then decreased (48 hours). PE, CS-O and CRP significantly improved earlier (7 days) than TXR (14 days). The median number of days to marker normalisation was 7, 9 and 14 for PE, CRP and CS-O, respectively. Marker agreement was excellent/very good at enrolment and fair/poor during disease recovery. LIMITATIONS: Analysis did not control for differences aetiology of aspiration or the lack of standardisation in treatment approach. CONCLUSIONS: PE was the earliest and most consistent marker indicating disease resolution. Serial CRP monitoring (72 hours) may provide an objective marker of early treatment response. Alongside PE normalisation, improvement in CS-O, CRP and TRX may assist in determining disease resolution and guide treatments, including limiting antibiotic exposure in dogs with aspiration-induced lung injury.

No adverse consequences associated with targeting clinical signs to initiate antimicrobial treatment of postoperative subclinical bacteriuria in dogs following surgical decompression of Hansen type I thoracolumbar disk herniation.

OBJECTIVE: To describe the prevalence of postoperative bacteriuria, clinical course of subclinical bacteriuria in the absence of antimicrobial intervention, clinical signs of bacteriuria that trigger antimicrobial treatment, and outcomes for dogs with subclinical bacteriuria following surgical decompression of acute intervertebral disc herniation (IVDH) Hansen type I. ANIMALS: Twenty client-owned dogs undergoing hemilaminectomy for acute (≤ 6 days) IVDH Hansen type I affecting the thoracolumbar spinal cord segments between August 2018 and January 2019. PROCEDURES: In this prospective study, dogs were serially evaluated at presentation, hospital discharge, 2 weeks postoperatively, and between 4 and 6 weeks postoperatively. Dogs were monitored for clinical signs of bacteriuria, underwent laboratory monitoring (CBC, biochemical analyses, urinalysis, urine bacterial culture), and were scored for neurologic and urinary status. In the absence of clinical signs, bacteriuria was not treated with antimicrobials. RESULTS: Four of the 18 dogs developed bacteriuria without clinical signs 4 days to 4 to 6 weeks after surgery. In all 4 dogs, bacteriuria resulted in lower urinary tract signs 13 to 26 weeks postoperatively. No dogs had evidence of systemic illness despite delaying antimicrobial treatment until clinical signs developed. New-onset incontinence was the only clinical sign in 3 dogs. All bacterial isolates had wide antimicrobial susceptibility. Bacteriuria and clinical signs resolved with beta-lactam antimicrobial treatment. CLINICAL RELEVANCE: Postoperative bacteriuria occurs in some dogs with IVDH Hansen type I and, when present, may lead to clinical signs over time. Clinical signs of bacteriuria may be limited to new-onset urinary incontinence, inappropriate urination, or both. Delaying antimicrobial treatment until clinical signs of bacteriuria developed did not result in adverse consequences or systemic illness.

Comparison of urine fibrinogen and interleukin-6 concentrations between healthy dogs and dogs with risk factors for enterococcal bacteriuria.

OBJECTIVE: To compare urine concentrations of fibrinogen (uFIB) and interleukin-6 (uIL-6) between dogs with risk factors for enterococcal bacteriuria and healthy dogs. SAMPLE: Banked urine samples with negative aerobic culture results from 8 dogs with urolithiasis, 9 dogs with anatomic abnormalities of the lower portion of the urinary tract (LUT), 10 dogs with LUT neoplasia, and 21 healthy control dogs. PROCEDURES: Urine creatinine concentration (uCrea) was determined by an automated biochemical analyzer, and uFIB and uIL-6 were determined by dog-specific ELISAs. The uFIB:uCrea and uIL-6:uCrea ratios were calculated for each sample to normalize intersample differences in urine concentration and were compared among the 4 experimental groups. RESULTS: Median uFIB:uCrea ratios for dogs with urolithiasis (0.72; interquartile [25th to 75 percentile] range [IQR], 0.46 to 3.48) and LUT neoplasia (6.16; IQR, 3.89 to 12.75), but not for dogs with LUT anatomic abnormalities (0.48; IQR, 0.27 to 0.69), were significantly greater than that for control dogs (0.17; IQR, 0.07 to 0.39). Median uIL-6: uCrea ratios for dogs with urolithiasis (0.48; IQR, 0.18 to 1.61), LUT anatomic abnormalities (0.25; IQR, 0.17 to 0.33), and LUT neoplasia (0.25; IQR, 0.12 to 1.01) were significantly greater than that for control dogs (0.08; IQR, 0.06 to 0.11). CONCLUSIONS AND CLINICAL RELEVANCE: The uFIB and uIL-6 in dogs with risk factors for enterococcal bacteriuria were generally greater than corresponding values in control dogs. Further investigation is necessary to determine the role of fibrinogen in enterococcal colonization of the urinary tract of dogs.

The influence of intermittent hypoxia, obesity, and diabetes on male genitourinary anatomy and voiding physiology.

We used male BTBR mice carrying the Lepob mutation, which are subject to severe and progressive obesity and diabetes beginning at 6 wk of age, to examine the influence of one specific manifestation of sleep apnea, intermittent hypoxia (IH), on male urinary voiding physiology and genitourinary anatomy. A custom device was used to deliver continuous normoxia (control) or IH to wild-type and Lepob/ob (mutant) mice for 2 wk. IH was delivered during the 12-h inactive (light) period in the form of 90 s of 6% O2 followed by 90 s of room air. Continuous room air was delivered during the 12-h active (dark) period. We then evaluated genitourinary anatomy and physiology. As expected for the type 2 diabetes phenotype, mutant mice consumed more food and water, weighed more, and voided more frequently and in larger urine volumes. They also had larger bladder volumes but smaller prostates, seminal vesicles, and urethras than wild-type mice. IH decreased food consumption and increased bladder relative weight independent of genotype and increased urine glucose concentration in mutant mice. When evaluated based on genotype (normoxia + IH), the incidence of pathogenic bacteriuria was greater in mutant mice than in wild-type mice, and among mice exposed to IH, bacteriuria incidence was greater in mutant mice than in wild-type mice. We conclude that IH exposure and type 2 diabetes can act independently and together to modify male mouse urinary function. NEW & NOTEWORTHY Metabolic syndrome and obstructive sleep apnea are common in aging men, and both have been linked to urinary voiding dysfunction. Here, we show that metabolic syndrome and intermittent hypoxia (a manifestation of sleep apnea) have individual and combined influences on voiding function and urogenital anatomy in male mice.

Growth of adenocarcinoma from canine pleural fluid on aerobic bacterial culture.

We report a case of canine adenocarcinoma with multi-organ metastasis in which colonies of adenocarcinoma cells grew upon aerobic bacterial culture of pleural effusion. Stained agar colonies were highly similar to rare suspicious cells seen on cytologic examination of the pleural effusion, as well as rare cells seen on cytologic examination of pancreatic and gastric wall fine-needle aspirates. Cells from colonies growing on agar media were mildly immunoreactive for cytokeratin. Histologic examination of tissues obtained at autopsy revealed pancreatic adenocarcinoma with vascular invasion and nodal, gastric, pulmonary, and pleural metastasis.

Mucoid Pseudomonas aeruginosa infection in a cat with severe chronic rhinosinusitis.

A 6-year-old male neutered Bengal cat was presented to the University of Wisconsin Veterinary Care Hospital with a history of severe chronic rhinitis that was unresolved from kittenhood. In weeks prior to presentation, the cat's upper respiratory signs had significantly worsened and a left-sided facial swelling overlying the left frontal sinus was noted. Skull computed tomography, rhinoscopy, bilateral nasal biopsies, bacterial and fungal cultures of fluid from the left frontal sinus, and cryptococcal fungal antigen testing were performed. The cat was diagnosed with severe chronic rhinosinusitis and determined to have an infection with a mucoid variant of Pseudomonas aeruginosa (P aeruginosa). This case highlights an atypical cytomorphologic appearance of the well-known bacterial pathogen, P aeruginosa, an appearance that could be confused cytologically with other microorganisms, such as septate fungi. Mucoid variants of P aeruginosa are often associated with progressive lung or airway disease in people with cystic fibrosis and have not been previously documented in feline respiratory tract disease. This report also presents a brief review of chronic rhinosinusitis (CRS) in cats and describes a novel interventional treatment approach to feline CRS via sinusotomy and sinus flushing for severely affected cats.

Viable Mycobacterium avium ssp. paratuberculosis isolated from calf milk replacer.

When advising farmers on how to control Johne's disease in an infected herd, one of the main recommendations is to avoid feeding waste milk to calves and instead feed calf milk replacer (CMR). This advice is based on the assumption that CMR is free of viable Mycobacterium avium ssp. paratuberculosis (MAP) cells, an assumption that has not previously been challenged. We tested commercial CMR products (n = 83) obtained from dairy farms around the United States by the peptide-mediated magnetic separation (PMS)-phage assay, PMS followed by liquid culture (PMS-culture), and direct IS900 quantitative PCR (qPCR). Conventional microbiological analyses for total mesophilic bacterial counts, coliforms, Salmonella, coagulase-negative staphylococci, streptococci, nonhemolytic Corynebacterium spp., and Bacillus spp. were also performed to assess the overall microbiological quality of the CMR. Twenty-six (31.3%) of the 83 CMR samples showed evidence of the presence of MAP. Seventeen (20.5%) tested positive for viable MAP by the PMS-phage assay, with plaque counts ranging from 6 to 1,212 pfu/50 mL of reconstituted CMR (average 248.5 pfu/50 mL). Twelve (14.5%) CMR samples tested positive for viable MAP by PMS-culture; isolates from all 12 of these samples were subsequently confirmed by whole-genome sequencing to be different cattle strains of MAP. Seven (8.4%) CMR samples tested positive for MAP DNA by IS900 qPCR. Four CMR samples tested positive by both PMS-based tests and 5 CMR samples tested positive by IS900 qPCR plus one or other of the PMS-based tests, but only one CMR sample tested positive by all 3 MAP detection tests applied. All conventional microbiology results were within current standards for whole milk powders. A significant association existed between higher total bacterial counts and presence of viable MAP indicated by either of the PMS-based assays. This represents the first published report of the isolation of viable MAP from CMR. Our findings raise concerns about the potential ability of MAP to survive manufacture of dried milk-based products.

Clinical performance of a commercial point-of-care urine culture system for identification of bacteriuria in dogs.

OBJECTIVE To evaluate the clinical performance of a commercially available compartmentalized urine culture and antimicrobial susceptibility test plate (CCSP) for identification of canine bacteriuria and assessment of isolate antimicrobial susceptibility. DESIGN Cross-sectional study. ANIMALS 71 dogs. PROCEDURES Urine samples (n = 84) were divided into 3 aliquots. One aliquot (reference culture) was plated on culture medium ≤ 1 hour after collection for quantitative culture and testing by standard laboratory methods, another was stored at 4°C for 24 hours (to mimic storage practices at primary care facilities) and then processed by standard methods, and the third was applied to a CCSP ≤ 1 hour after collection to be processed and interpreted according to manufacturer instructions. Results were compared with those for reference culture, which was used as the criterion reference standard. Sensitivity, specificity, positive and negative predictive values, and agreement between methods was evaluated. RESULTS 43 isolates (25 single and 9 multiple isolates) were identified in 34 reference cultures. All results for stored cultures were identical to those for reference cultures. Overall sensitivity of the CCSP method to detect bacteriuria was 93%, and specificity was 100%. Thirty-three of 43 (77%) and 19 of 33 (58%) CCSP bacterial isolates were correctly identified to the genus and species level, respectively. The CCSP antimicrobial susceptibility results matched those for reference cultures for 13 of 33 (39%) isolates evaluated. CONCLUSIONS AND CLINICAL RELEVANCE Limitations of the CCSP method included inaccuracy of some antimicrobial susceptibility test results and failure to correctly identify bacteriuria in some dogs.

Multilaboratory Survey To Evaluate Salmonella Prevalence in Diarrheic and Nondiarrheic Dogs and Cats in the United States between 2012 and 2014.

Eleven laboratories collaborated to determine the periodic prevalence of Salmonella in a population of dogs and cats in the United States visiting veterinary clinics. Fecal samples (2,965) solicited from 11 geographically dispersed veterinary testing laboratories were collected in 36 states between January 2012 and April 2014 and tested using a harmonized method. The overall study prevalence of Salmonella in cats (3 of 542) was <1%. The prevalence in dogs (60 of 2,422) was 2.5%. Diarrhea was present in only 55% of positive dogs; however, 3.8% of the all diarrheic dogs were positive, compared with 1.8% of the nondiarrheic dogs. Salmonella-positive dogs were significantly more likely to have consumed raw food (P = 0.01), to have consumed probiotics (P = 0.002), or to have been given antibiotics (P = 0.01). Rural dogs were also more likely to be Salmonella positive than urban (P = 0.002) or suburban (P = 0.001) dogs. In the 67 isolates, 27 unique serovars were identified, with three dogs having two serovars present. Antimicrobial susceptibility testing of 66 isolates revealed that only four of the isolates were resistant to one or more antibiotics. Additional characterization of the 66 isolates was done using pulsed-field gel electrophoresis and whole-genome sequencing (WGS). Sequence data compared well to resistance phenotypic data and were submitted to the National Center for Biotechnology Information (NCBI). This study suggests an overall decline in prevalence of Salmonella-positive dogs and cats over the last decades and identifies consumption of raw food as a major risk factor for Salmonella infection. Of note is that almost half of the Salmonella-positive animals were clinically nondiarrheic.

Prevalence and clinical outcome of subclinical bacteriuria in female dogs.

OBJECTIVE: To determine the prevalence of subclinical bacteriuria and its natural clinical course over a 3-month period in healthy female dogs. DESIGN: Observational, prospective, cross-sectional study. ANIMALS: 101 healthy client-owned female dogs. PROCEDURES: In all dogs, screening clinicopathologic tests and bacteriologic culture of urine were performed. In culture-positive dogs, subclinical bacteriuria was confirmed by 2 positive culture results within 2 weeks and dogs were reevaluated at 3 months. RESULTS: The prevalence of subclinical bacteriuria in healthy female dogs was 9 of 101 (8.9%). Three-month follow-up data were available for 8 of 9 dogs with subclinical bacteriuria. Four dogs had persistent bacteriuria, and 4 had transient bacteriuria. No dogs with subclinical bacteriuria developed clinical signs during the 3-month observation period. Subclinical bacteriuria was diagnosed in 6 of 51 (12%) young and middle-aged dogs and 3 of 50 (6.0%) senior and geriatric dogs. No significant difference was found in the prevalence of subclinical bacteriuria with age. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that subclinical bacteriuria is a nonprogressive condition in healthy female dogs and can be persistent or transient. No significant difference in the prevalence of subclinical bacteriuria in young and middle-aged dogs versus senior and geriatric dogs was detected. No dogs with subclinical bacteriuria developed clinical signs requiring antimicrobial treatment during the 3-month observation period. Healthy female dogs with subclinical bacteriuria may be a population of dogs in which antimicrobial treatment is unnecessary.

Impact of disinfectant-filled foot mats on mechanical transmission of bacteria in a veterinary teaching hospital.

OBJECTIVE: To evaluate the efficacy of disinfectant-filled foot mats at reducing tracking of Salmonella enterica and overall bacterial contamination on floors in a veterinary teaching hospital. DESIGN: Prospective study. Samples-Bacteria collected from floors before and after placement of disinfectant-filled foot mats. PROCEDURES: Foot mats filled with a phenolic-based disinfectant were placed at key transition areas in common-use corridors between the large animal hospital (LAH) and small animal hospital in a veterinary medical teaching hospital. Microbiological samples were collected for total bacterial counts and for the presence of S enterica at 14 designated sample sites in the veterinary medical teaching hospital. Samples were collected at regular intervals for 7 months before mat placement and for 13 months after mat placement. RESULTS: Median numbers of aerobic bacteria isolated before and after disinfectant mat placement were not significantly different for most sites sampled. For 3 of the 4 transition areas between the LAH and connecting common-use corridor, there was a significant difference in median bacterial counts on either side of the threshold. This difference was significant regardless of whether a disinfectant mat was present or not. Salmonella enterica isolates were cultured from several sites in the LAH and sites outside the LAH, irrespective of the presence of a disinfectant mat. CONCLUSIONS AND CLINICAL RELEVANCE: -Disinfectant-filled mats may not be uniformly effective in reducing the bacterial load on floors or in reducing mechanical tracking of S enterica from contaminated areas in a veterinary teaching hospital. Further studies are needed to determine effective measures to reduce mechanical transmission of bacteria on footwear in veterinary hospitals.

Methicillin-resistant staphylococci: implications for our food supply?

Food-borne intoxication, caused by heat-stable enterotoxins produced by Staphylococcus aureus, causes over 240,000 cases of food-borne illness in the United States annually. Other staphylococci commonly associated with animals may also produce these enterotoxins. Foods may be contaminated by infected food handlers during slaughter and processing of livestock or by cross-contamination during food preparation. S. aureus also causes a variety of mild to severe skin and soft tissue infections in humans and other animals. Antibiotic resistance is common in staphylococci. Hospital-associated (HA) S. aureus are resistant to numerous antibiotics, with methicillin-resistant S. aureus (MRSA) presenting significant challenges in health care facilities for over 40 years. During the mid-1990s new human MRSA strains developed outside of hospitals and were termed community-associated (CA). A few years later, MRSA was isolated from horses and methicillin resistance was detected in Staphylococcus intermedius/pseudintermedius from dogs and cats. In 2003, a livestock-associated (LA) MRSA strain was first detected in swine. These methicillin-resistant staphylococci pose additional food safety and occupational health concerns. MRSA has been detected in a small percentage of retail meat and raw milk samples indicating a potential risk for food-borne transmission of MRSA. Persons working with animals or handling meat products may be at increased risk for antibiotic-resistant infections. This review discusses the scope of the problem of methicillin-resistant staphylococci and some strategies for control of these bacteria and prevention of illness.

A case of apparent canine erysipeloid associated with Erysipelothrix rhusiopathiae bacteraemia.

BACKGROUND: Erysipelothrix rhusiopathiae is a Gram-positive facultative anaerobe found worldwide and is most commonly associated with skin disease in swine, while anecdotal reports of cases in dogs have been associated with endocarditis. HYPOTHESIS/OBJECTIVES: Clinicians should consider systemic infectious diseases as a potential cause of erythematous skin lesions. ANIMALS: A 5-year-old female spayed Labrador retriever presented with lethargy, anorexia and erythematous skin lesions while receiving immunosuppressive therapy for immune-mediated haemolytic anaemia. Four days prior to presentation, the dog had chewed on a raw turkey carcase. METHODS: Complete blood count, serum chemistry profile, urinalysis and blood cultures. RESULTS: Blood cultures yielded a pure growth of E. rhusiopathiae serotype 1b. Amoxicillin 22 mg/kg orally twice daily for 2 weeks and discontinuation of azathioprine resulted in remission of fever and skin lesions. CONCLUSIONS AND CLINICAL IMPORTANCE: This report is the first documentation, to the best of the authors' knowledge, of Erysipelothrix infection, a known zoonosis, in an immunosuppressed dog, highlighting the need for infectious disease monitoring in patients receiving such therapy. This information may also help educate veterinarians to include Erysipelothrix infection as a differential diagnosis in dogs with fever and skin lesions, as well as the role of blood cultures in diagnosing this disease.

Nocardia arthritidis infection in the distal metaphysis of the metatarsal III and IV bone of a heifer.

CASE DESCRIPTION: A 19-month-old 536.4-kg (1,180-lb) Brown Swiss heifer was referred for evaluation of a firm swelling over the distal aspect of the right metatarsal region and chronic lameness in the right hind limb. CLINICAL FINDINGS: Examination of radiographs of the right metatarsophalangeal joints revealed an expansile, smoothly marginated, cyst-like lesion within the distal metaphysis of the metatarsal III and IV bone. Differential diagnoses included bone abscess, bone cyst, aneurysmal bone cyst, neoplasia, osteomyelitis, and metabolic bone disease. Aerobic microbial culture of the aspirate yielded moderate growth of branching, gram-positive, rod-shaped bacteria, which were presumptively identified as Nocardia spp. The isolate was subsequently identified as Nocardia arthritidis by 16S rRNA gene sequence analysis. TREATMENT AND OUTCOME: The lesion was surgically debrided, lavaged, and bandaged. Exercise was restricted, and systemic and local administration of antimicrobials was instituted. After a communication between the abscess and the metatarsophalangeal joints was iatrogenically created, the extralabel use of aminoglycosides was initiated. The heifer had noticeable clinical improvement within 2 weeks after initial evaluation and reportedly had no evidence of lameness and minimal external blemishes 3 months after the second evaluation. CLINICAL RELEVANCE: To our knowledge, this is the first report on the diagnosis and management of a long-bone abscess attributable to N arthritidis infection in cattle. Complications encountered during treatment and the decision to engage in extralabel use of antimicrobial agents in the heifer described here may serve as a guide for food animal practitioners faced with the treatment of valuable cattle.

Bacterial culture results from liver, gallbladder, or bile in 248 dogs and cats evaluated for hepatobiliary disease: 1998-2003.

BACKGROUND: Information is lacking on the prevalence and susceptibility patterns of bacterial isolates in dogs and cats with suspected hepatobiliary disease. OBJECTIVES: To characterize the prevalence, identity, and antimicrobial susceptibility of common hepatobiliary isolates from such patients. ANIMALS: Dogs and cats presented to the University of Wisconsin-Madison Veterinary Medical Teaching Hospital for which samples of bile, gallbladder, or liver were submitted for culture from 1998 to 2003, including 190 dogs (192 culture episodes) and 58 cats (61 culture episodes). METHODS: Cases were identified from the microbiology laboratory database. Data from patient medical records were extracted, including the history of antimicrobial administration, the presence of fever, the results of CBC and serum biochemistry, the presence of biliary obstruction or hepatobiliary inflammation, and the results of aerobic and anaerobic bacterial cultures and aerobic antimicrobial susceptibilities. RESULTS: Biliary cultures yielded a significantly higher percentage of positive results overall (30% [18 of 60]) than did hepatic cultures (7% [15 of 215]). In patients with cholecystitis, 62% (8 of 13) had positive biliary cultures. In patients with hepatic inflammation, 23% (7 of 30) had positive bile cultures, whereas only 6% (6 of 103) had positive hepatic cultures. Escherichia coli, Enterococcus spp., Bacteroides spp., Streptococcus spp., and Clostridium spp. were the most common true-positive isolates. More than 80% of Enterobacteriaceae were susceptible to ciprofloxacin or aminoglycosides, with only 30-67% susceptible to first-generation aminopenicillins and cephalosporins. Liver samples obtained by surgery or laparoscopy were more likely to yield positive cultures than those obtained by percutaneous needle biopsy.

Surveillance of Staphylococcus aureus in veterinary teaching hospitals.

Staphylococcus aureus isolates (n = 70) from 65 patients (36 canine, 18 equine, 7 bovine, 2 avian, and 2 feline) at seven veterinary teaching hospitals in the United States were studied. The majority of patients (83%) with an S. aureus infection were canine and equine, but this may have reflected a sample bias based on clinic case loads and diagnostic lab submissions at the participating institutions. Fourteen percent of patients with an S. aureus infection were infected with a methicillin-resistant S. aureus (MRSA) isolate. Six of seven institutions had at least one MRSA infection during the study. Pulsed-field gel electrophoresis on 63 of the 70 isolates yielded 58 unique strains of S. aureus. None of the strain types of the MRSA isolates matched each other or the type of any other S. aureus isolate. The proportions of patients infected with an MRSA isolate were not significantly different between institutions or animal species (P > or = 0.222). Methicillin-resistant S. aureus isolates in this study seemed to be community acquired rather than hospital acquired.

Molecular characterization of Staphylococcus intermedius carriage by healthy dogs and comparison of antimicrobial susceptibility patterns to isolates from dogs with pyoderma.

We conducted an epidemiological study of Staphylococcus intermedius using arbitrarily primed PCR (AP-PCR) and antibiograms. One hundred and twenty-five S. intermedius isolates were recovered from the oral cavity and/or cranial hair coat of healthy dogs enrolled in a pet therapy program. Commensal S. intermedius was cultured from 32% of the oral cavity cultures and 13% of the cranial hair coat cultures. We characterized the colonization of the dogs as transient, intermittent, or persistent. For dogs characterized as persistently colonized, 73% of the isolates came from the oral cavity. These isolates were also genotyped by AP-PCR. A single major AP-PCR type was observed in 91% of the dogs (n=22); minor variations were frequently observed in these major types. Antibiograms of these commensal isolates were compared to antibiograms from 97 historical clinical isolates (1988-1992) obtained from cases of canine pyoderma. Resistance was most often observed to penicillin (64% and 55%) and tetracycline (38% and 38%) among the commensal and clinical isolates, respectively. The commensal isolates were significantly less resistant to erythromycin, clarithromycin, clindamycin, and trimethoprim/sulfamethoxazole. Our data suggests that differences in both genotype and antimicrobial susceptibility phenotypes exist among S. intermedius strains isolated from different anatomic sites from the same dog and supports the opportunistic nature of S. intermedius in canine infections.

Isolation of Salmonella spp from the environment of dairies without any history of clinical salmonellosis.

OBJECTIVE: To determine whether Salmonella spp could be isolated from the environment of free stall dairies in Wisconsin without any history of clinical salmonellosis and determine the serotype and antimicrobial susceptibility of any Salmonella isolates recovered from the environment. DESIGN: Cross-sectional study. STUDY POPULATION: 20 free stall dairies with no history of clinical salmonellosis. PROCEDURES: Dairy owners completed a questionnaire regarding management and production practices. Multiple swab samples were obtained from throughout the free stall facilities and submitted for bacterial culture for Salmonella spp. Odds ratios were calculated to compare herd-level risk factors between dairies from which Salmonella organisms were isolated and herds from which Salmonella organisms were not isolated. RESULTS: Salmonella organisms were isolated from 9 of the 20 (45%) dairies. Salmonella serotype Meleagridis was isolated from 4 dairies, S. Meleagridis and S. Kentucky were isolated from 2 dairies, S. Meleagridis and S. Cyprus were isolated from 1 dairy, S. Cerro was isolated from 1 dairy, and S. Corvallis was isolated from 1 dairy. All isolates were susceptible to all antimicrobial agents tested. None of the potential risk factors analyzed demonstrated a significant association with an increased likelihood of isolating Salmonella spp. CONCLUSIONS AND CLINICAL RELEVANCE: Environmental Salmonella contamination was demonstrated on free stall dairies with no history of clinical salmonellosis.