In This Issue • July 1, 2018


Veterinarians, caught in a chronic opioid shortage, are turning to other anesthetics that may be less effective. In other news, the social climate at veterinary colleges is improving overall, but among students, sexism, racism, and homophobia may be increasing, according to study results.

See page 12

Letters to the Editor

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What Is Your Neurologic Diagnosis?

See page 39

ECG of the Month

See page 46

Pathology in Practice

See pages 49, 53

farad digest

Consequences of fipronil exposure in egg-laying hens

Federal law allowing extralabel drug use in the United States does not include products registered by the US Environmental Protection Agency. Thus, questions about withdrawal intervals following extralabel use of pesticides in food animals put FARAD in a precarious situation.

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Small Animals

A benchtop analyzer for measurement of ammonium concentration in canine plasma

Measurement of plasma ammonium concentration is considered a useful diagnostic test for hepatobiliary disease in dogs. However, ammonium is very labile, and samples must be analyzed within 20 minutes after collection. A new dry chemistry benchtop analyzer that measures ammonium concentration along with concentrations of multiple other analytes has recently become commercially available. In a study evaluating clinical performance of this analyzer that used 32 blood samples from 30 dogs (16 with and 14 without suspected hepatobiliary disease), clinical performance was considered acceptable for detection of high versus normal ammonium concentrations.

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Oral and dental anomalies in purebred, brachycephalic Persian and Exotic cats

Information on the prevalence and types of dental anomalies in brachycephalic cats would help veterinarians counseling owners of these cats and individuals considering obtaining them. In a study of 42 Persian and 8 Exotic cats, 36 (72%) had malocclusions. Crowding of the teeth was evident in 28 (56%) cats, and malpositioned teeth were noted in 32 (64%). Six (12%) cats had hyperdontia and 32 (64%) had hypodontia. Periodontal disease was reported in 44 (88%) cats; tooth resorption was evident in 35 (70%). Overall, 123 of 1,349 (8.7%) teeth had external inflammatory resorption and 82 (6.1%) had external replacement resorption.

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Surgical excision with or without hypofractionated radiotherapy in dogs with oral squamous cell carcinoma or fibrosarcoma

Few reports describe outcome of combining surgery with adjuvant radiotherapy for dogs with nonmelanotic oral malignancies. In a study of 87 dogs that underwent maxillectomy or mandibulectomy for treatment of oral, nontonsillar, squamous cell carcinoma or fibrosarcoma, tumor type was a significant predictor of survival time. Dogs undergoing postoperative radiotherapy after incomplete excision of oral SCCs had a significantly longer median survival time (2,051 days) than did dogs with incompletely excised tumors and no radiotherapy (181 days). Postoperative radiotherapy of dogs with incompletely excised FSAs did not appear to offer protective value.

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Outcome and factors associated with prognosis for dogs with early-stage anal sac adenocarcinoma treated with surgery alone

A study of 34 dogs with early-stage (largest diameter < 3.2 cm), nonmetastatic anal sac adenocarcinoma indicated a favorable outcome following surgical removal of the primary tumor alone. Median survival time was 1,237 days. Seven dogs had tumor recurrence and 9 developed metastatic disease at a median of 354 and 589 days, respectively, after primary tumor removal. Cellular pleomorphism was positively associated with development of metastatic disease, but no other factors associated with outcome were identified. Findings suggested that routine rectal examination may be a simple and useful method for detecting early-stage ASACA in dogs.

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Face, construct, and concurrent validity of a simulation model for laparoscopic ovariectomy in standing horses

Because ovariectomy is one of the most common indications for laparoscopic surgery in horses, the authors developed a simulation model for laparoscopic ovariectomy in standing horses. Testing of the model with 15 veterinary students and 4 equine surgeons with experience in laparoscopy indicated that the model replicated the operative experience to a high degree (face validity), that performance scores were significantly different between the students and the equine surgeons (construct validity), and that performance scores for the model correlated with scores for a previously validated test of laparoscopic skills (concurrent validity).

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Recovery of horses from general anesthesia after induction with propofol and ketamine versus midazolam and ketamine

For horses undergoing short (ie, 60 minutes) periods of general anesthesia, recovery quality may be better following induction with propofol and ketamine, compared with midazolam and ketamine. Six horses were premedicated with xylazine, and general anesthesia was then induced with midazolam or propofol, followed by ketamine, and maintained with isoflurane. After 60 minutes, horses were given romifidine and allowed to recover unassisted. Number of attempts to stand was significantly lower and recovery quality scores were significantly better when horses received propofol than when they received midazolam.

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Clinical features and outcome in horses with severe large intestinal thickening diagnosed with transabdominal ultrasonography

A review of medical records for 25 horses found to have severe large intestinal thickening (ie, large intestinal wall thickness ≥ 9 mm) by means of transabdominal ultrasonography revealed a variety of underlying conditions. Severe large intestinal thickening (range, 9 to 46.6 mm; mean ± SD, 18.8 ± 6.8 mm) was the primary ultrasonographic finding in all horses. Ultrasonographic examination of all abdominal zones was helpful to determine the extent of thickening and identify additional findings that helped prioritize differential diagnoses. Eleven horses survived and had resolution of clinical signs; an additional horse survived but continued to have intermittent colic.

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