Background Many medical conditions are thought to cause gastroduodenal ulceration or erosion (GUE) in dogs. However, evidence for the association between many of these conditions and GUE in dogs is lacking. Objective To identify medical conditions associated with GUE in dogs. Animals One hundred and sixty‐eight dogs with GUE and 168 randomly selected control dogs without evidence of GUE identified on necropsy between January 2008 and September 2018. Methods Patient signalment, blood urea nitrogen (BUN) and serum creatinine concentrations, recently administered ulcerogenic drugs, as well as necropsy findings were recorded. The association between these findings and presence of GUE was assessed by univariable and multivariable analysis. Results In the final multivariable model, the following factors were associated with GUE: Nonsteroidal anti‐inflammatory drug (NSAID) administration (odds ratio [OR], 6.3; 95% confidence interval [CI], 2.3‐17.4; P = .0004), glucocorticoid administration (OR, 3.0; 95% CI, 1.5‐5.9; P = .001), gastrointestinal neoplasia (OR, 13.5; 95% CI, 1.7‐108.0; P = .01) and gastrointestinal mechanical disease (foreign bodies, gastric dilatation, and volvulus; OR, 4.8; 95% CI, 1.2‐19.7; P = .03). Additionally, working dog breeds were predisposed to GUE compared to mixed breed dogs (OR, 2.8; 95% CI, 1.1‐7.4; P = .04). Insufficient clinical data was available to either support or refute a role of other putative risk factors evaluated. Conclusion and Clinical Importance Administration of NSAID or glucocorticoid and gastrointestinal neoplasia or mechanical disease were associated with GUE in dogs. The potential predisposition of working breed dogs for GUE requires further investigation.

bStaphylococcus pseudintermedius is the most common microorganism isolated from canine pyoderma and postoperative wound infections. The prevalence of methicillin-resistant S. pseudintermedius (MRSP) has increased, and recently, isolates that are resistant not only to methicillin but also to other classes of antibiotic drugs, including aminoglycosides, have become common. A total of 422 S. pseudintermedius isolates collected from 413 dogs were analyzed for amikacin and methicillin resistance using broth microdilution and disk diffusion testing. Methicillin-resistant isolates were significantly (P < 0.0001) more likely to be resistant to amikacin (37%, 31/84) than were methicillin-susceptible isolates (7%, 22/338). Additionally, resistance to non-␤-lactam antibiotics was significantly associated with resistance to amikacin irrespective of methicillin resistance. Among the 422 isolates, 32 that tested positive for amikacin resistance by broth microdilution or disk diffusion testing were investigated further for the presence of aminoglycoside-modifying enzyme genes using multiplex PCR. Of these isolates, 66% (21/32) were methicillin resistant. In contrast to previous studies of Staphylococcus aureus, the most prevalent gene detected was aph(3=)-IIIa found in 75% (24/32) of isolates followed by aac(6=)/aph(2؆) and ant(4=)-Ia in 12% (4/32) and 3% (1/32), respectively. Understanding the differences in antimicrobial resistance gene carriage between different species of Staphylococcus may improve antimicrobial drug selection for clinical therapy and provide insights into how resistance develops in S. pseudintermedius.

Parosteal osteosarcoma is a rare, slow-growing tumor most commonly arising from the surface of long bones. Tissue or histological sections from 5 dogs and 1 cat with zygomatic arch masses were examined. Clinical presentations varied from chronic sneezing to facial swelling. Imaging consistently demonstrated osseous proliferation in the area of the zygomatic arch. Histologically, the masses were characterized by well-differentiated fibro-osseous and chondroid components that radiated outward from the periosteum of the zygomatic bone. Cellular atypia and mitotic figures were uncommon. Parosteal osteosarcomas have previously been reported in the skulls of dogs and cats, but only 1 has been reported on the zygomatic arch. Initially, these tumors are of low histologic low grade, but with time, they can show more aggressive behavior and invade the underlying bone.

In the United States, veterinary use of mupirocin is primarily limited to the treatment of canine pyoderma caused by methicillinresistant Staphylococcus pseudintermedius (MRSP). In this study, only 1 of 581 S. pseudintermedius isolates tested was resistant to mupirocin and carried the high-level mupirocin resistance gene, ileS2, on a plasmid. Staphylococcus pseudintermedius is the primary bacterial pathogen isolated from canine pyoderma and also causes postsurgical infections in dogs (1, 2). Methicillin resistance and multidrug resistance are increasing in S. pseudintermedius, thus limiting the options for therapeutic treatment of canine skin infections (2). Mupirocin is a bacteriostatic antibiotic that reversibly binds to isoleucyl-tRNA synthetase to disrupt protein synthesis and is widely used to eliminate nasal carriage of methicillin-resistant Staphylococcus aureus (MRSA) in human MRSA carriers (3). Mupirocin has been used on only a limited basis in veterinary medicine but is approved in the United States for the treatment of bacterial skin infections and superficial pyoderma in dogs (4).In S. aureus, two levels of mupirocin resistance have been identified. Low-level mupirocin resistance occurs due to a point mutation to the chromosomal ileS gene that encodes the native isoleucyl-tRNA synthetase. The MIC for mupirocin for staphylococci carrying the low-level resistance is Ն8 g/ml but Յ256 g/ml (5). Conversely, high-level mupirocin resistance (MIC of Ն512 g/ml) is usually conferred by the plasmid-borne ileS2, although a chromosomal location of ileS2 has been reported (5). Recently, ileS2 plasmid-mediated mupirocin resistance was found in a mupirocin-resistant, methicillin-susceptible S. pseudintermedius strain isolated from a dog in Croatia (6). The goal of the present study was to determine the prevalence of mupirocin resistance in S. pseudintermedius isolated from patients presented to a veterinary hospital in Texas.In this study, 581 isolates of S. pseudintermedius were screened for phenotypic low-level mupirocin resistance. Isolates were collected from veterinary patients, predominantly dogs (n ϭ 446), but also included isolates from cats (n ϭ 9). Some patients were cultured at multiple sites and contributed more than one isolate, and of these, 21 patients contributed more than two isolates. The isolates included a historical collection of 403 isolates from clinical infections and contained both methicillin-resistant S. pseudintermedius (MRSP) isolates (n ϭ 153) and methicillin-susceptible S. pseudintermedius (MSSP) isolates (n ϭ 250). The isolates from clinical infections were collected from the following anatomic sites: skin (n ϭ 96), external ear canal (n ϭ 31), wounds (n ϭ 79), postoperative infections (n ϭ 33), urine or the urinary tract (n ϭ 87), and other sources (n ϭ 77). Additional isolates were collected during a study of MRSP prevalence in canine patients without clinical staphylococcal infection that presented for elective orthopedic procedures. The MRSP prevalence study yielded 178 S. pseudin...

OBJECTIVE- To determine effects of hip joint osteoarthritis on radiographic measures of hip joint laxity and congruence. DESIGN- Longitudinal study. ANIMALS- 40 Labrador Retrievers. PROCEDURES- Dogs were assigned to 2 groups based on radiographic evidence of osteoarthritis. Dogs in the osteoarthritis group were free of osteoarthritis at initial radiographic evaluation (t(1)) and developed osteoarthritis by a subsequent radiographic evaluation (t(2)). Dogs in the nonosteoarthritis group had no radiographic osteoarthritis at either evaluation. Hip joint laxity was quantified by use of the distraction index (DI) from a distraction radiographic view and use of the Norberg angle (NA) from a ventrodorsal hip-extended radiographic view. The compression index (CI) from a compression radiographic view was used as a measure of joint congruence (concentricity). RESULTS- Hip joint laxity (NA or DI) did not change over time in the nonosteoarthritis group. Mean hip joint laxity (NA and DI) for the osteoarthritis group was greater at t(1) than for the nonosteoarthritis group. With the onset of osteoarthritis, mean NA decreased significantly and mean CI increased significantly, but mean DI remained unchanged. CONCLUSIONS AND CLINICAL RELEVANCE- No radiographic evidence for compensatory hip joint tightening associated with osteoarthritis was detected. Hip-extended radiography revealed that hip joints got looser with osteoarthritis and NA decreased. Hip joint laxity (DI) on distraction radiographs was unchanged by the onset of osteoarthritis and remained constant in the osteoarthritis and nonosteoarthritis groups at both evaluations. However, the CI increased with osteoarthritis, as reflected in nonzero indices (incongruence). The CI may be a valid marker for early hip joint osteoarthritis.