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OBJECTIVE: To compare serum triglyceride concentrations obtained after food had been withheld (i.e., fasting concentrations) in dogs with epilepsy that had been treated long term (> or = 3 months) with phenobarbital or with phenobarbital and potassium bromide with concentrations in healthy control dogs. DESIGN: Cross-sectional study. ANIMALS: 57 epileptic dogs that had been treated with phenobarbital (n=28) or with phenobarbital and bromide (29) and 57 healthy, untreated control dogs matched on the basis of age, breed, sex, neuter status, and body condition score. PROCEDURES: Blood samples were collected after food had been withheld for at least 12 hours, and serum biochemical and lipid concentrations were determined. Oral fat tolerance tests were performed in 15 control dogs and 9 dogs with epilepsy treated with phenobarbital alone. RESULTS: 19 of the 57 (33%) epileptic dogs had fasting serum triglyceride concentrations greater than the upper reference limit. Nine (16%) dogs had a history of pancreatitis, and 5 of the 9 had high fasting serum triglyceride concentrations at the time of the study. A significant relationship was found between body condition score and fasting serum triglyceride concentration in all dogs, but serum triglyceride concentration was not significantly associated with phenobarbital dosage or serum phenobarbital concentration. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that dogs treated long term with phenobarbital or with phenobarbital and bromide may develop hypertriglyceridemia. Fasting serum triglyceride concentration should be periodically monitored in dogs treated with phenobarbital because hypertriglyceridemia is a risk factor for pancreatitis.  相似文献   
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OBJECTIVE: To evaluate factors associated with response to treatment, remission duration, and survival in cats with low-grade lymphoma affecting various organ systems. DESIGN: Retrospective case series. Sample POPULATION: 41 cats with histologically confirmed low-grade lymphocytic lymphoma. PROCEDURES: Medical records and biopsy specimens of cats with histologically confirmed low-grade lymphocytic lymphoma of various organ systems treated with prednisone and chlorambucil between 1995 and 2005 were reviewed. The Kaplan-Meier method was used to estimate remission duration and survival. Factors potentially associated with prognosis were compared. RESULTS: Common clinical signs were weight loss (83%), vomiting (73%), anorexia (66%), and diarrhea (58%). Seventy-eight percent of cats tested had low serum cobalamin concentrations. Lymphoma was confined to the gastrointestinal tract in 68% of cats. Fifty-six percent of cats achieved a complete response to treatment, and 39% achieved a partial response. Five percent of cats had no response. No association was found between any risk factors (including anatomic site) and response to treatment. Partial response was associated with shorter remission duration, compared with complete response; median remission duration was 428 days for cats achieving a partial response, compared with 897 days for cats achieving a complete response. No other factors were associated with remission duration. Overall median survival time was 704 days. No factors were significantly associated with survival time. CONCLUSIONS AND CLINICAL RELEVANCE: Most cats with lymphocytic lymphoma responded to treatment with prednisone and chlorambucil, and most factors evaluated were not associated with outcome.  相似文献   
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Objective To describe a slowly progressive retinopathy (SPR) in Shetland Sheepdogs. Animals Forty adult Shetlands Sheepdogs with ophthalmoscopic signs of SPR and six normal Shetland Sheepdogs were included in the study. Procedure Ophthalmic examination including slit‐lamp biomicroscopy and ophthalmoscopy was performed in all dogs. Electroretinograms and obstacle course‐test were performed in 13 affected and 6 normal dogs. The SPR dogs were subdivided into two groups according to their dark‐adapted b‐wave amplitudes. SPR1‐dogs had ophthalmoscopic signs of SPR, but normal dark‐adapted b‐wave amplitudes. Dogs with both ophthalmoscopic signs and subnormal, dark‐adapted b‐wave amplitudes were assigned to group SPR2. Eyes from two SPR2 dogs were obtained for microscopic examination. Results The ophthalmoscopic changes included bilateral, symmetrical, greyish discoloration in the peripheral tapetal fundus with normal or marginally attenuated vessels. Repeated examination showed that the ophthalmoscopic changes slowly spread across the central parts of the tapetal fundus, but did not progress to obvious neuroretinal thinning presenting as tapetal hyper‐reflectivity. The dogs did not appear seriously visually impaired. SPR2 showed significantly reduced b‐wave amplitudes throughout dark‐adaptation. Microscopy showed thinning of the outer nuclear layer and abnormal appearance of rod and cone outer segments. Testing for the progressive rod–cone degeneration ( prcd )‐mutation in three dogs with SPR was negative. Conclusion Slowly progressive retinopathy is a generalized rod–cone degeneration that on ophthalmoscopy looks similar to early stages of progressive retinal atrophy. The ophthalmoscopic findings are slowly progressive without tapetal hyper‐reflectivity. Visual impairment is not obvious and the electroretinogram is more subtly altered than in progressive retinal atrophy. The etiology remains unclear. SPR is not caused by the prcd‐mutation.  相似文献   
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A retrospective study of the demographics of the Canadian dairy industry was conducted using data derived from Statistics Canada’s Census of Agriculture from 1991 to 2011. This longitudinal study shows that Canada’s dairy industry has undergone considerable consolidation. From 1991 to 2011, the number of dairy producers and dairy farms decreased by 48.9% and 61.9%, respectively. Furthermore, this trend in consolidation is likely to continue; nearly half (45.8%) of all dairy producers in Canada were ≥ 50 y of age in 2011. Not only will most of these producers be retired by 2021, but younger producers will also exit the industry for other reasons. These findings mirror what is occurring in Canada’s cow-calf industry, underscoring that supply-managed sectors experience demographic consolidation similar to non-supply managed sectors. These substantial changes will have ramifications for the veterinary profession. There will be fewer but larger farms, and the services and knowledge demanded of veterinarians will change accordingly, which has implications for food animal veterinary education.  相似文献   
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A 10-year-old neutered female cat had chylothorax, precaval syndrome, and a mediastinal granuloma resulting from infection with Cryptococcus neoformans. Diagnosis of a chylous effusion was made by cytologic examination of pleural fluid and by finding higher triglyceride levels in the effusion than in serum (825 vs. 64 mg/dl, respectively). Postmortem examination revealed cryptococcal organisms in the mediastinal granuloma, lungs, cerebral meninges, and connective tissues adjacent to the thyroid gland. Chylous effusion in a cat associated with cryptococcosis has not been reported previously. Cryptococcosis should be included in the differential diagnosis in chylous effusions in cats.  相似文献   
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Accurate antimicrobial drug use data are needed to enlighten discussions regarding the impact of antimicrobial drug use in agriculture. The primary objective of this study was to investigate the perceived accuracy and clarity of different methods for reporting antimicrobial drug use information collected regarding beef feedlots. Producers, veterinarians, industry representatives, public health officials, and other knowledgeable beef industry leaders were invited to complete a web-based survey. A total of 156 participants in 33 US states, 4 Canadian provinces, and 8 other countries completed the survey. No single metric was considered universally optimal for all use circumstances or for all audiences. To effectively communicate antimicrobial drug use data, evaluation of the target audience is critical to presenting the information. Metrics that are most accurate need to be carefully and repeatedly explained to the audience.  相似文献   
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