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Abstract

Objective

To determine the usefulness of a new method of measuring acoustic backscatter and attenuation in the liver of dogs with experimental steroid-induced hepatopathy.

Animals

10 clinically normal dogs.

Procedure

Steroid hepatopathy was induced by daily injections of prednisone (2 mg/kg of body weight, IM). Dogs were evaluated histologically and were sonographically imaged on days 0, 3, 7, 10, and 14. Acoustic backscatter and attenuation were measured from in vivo images of dogs, using a video signal method, and compared with results obtained from analysis of the unprocessed radio frequency signal.

Results

Histologic evaluation revealed midzonal, predominantly water-filled vacuoles in hepatocytes by day 7, which persisted for the remainder of the study and significantly (P = 0.0001) increased liver weight on day 14. Attenuation and backscatter increased during the experimental period. Mean effective attenuation difference was higher (P = 0.015) in the liver imaged through a left paraxyphoid window in experimental dogs by day 3. Significantly (P < 0.05) greater attenuation persisted in the liver of experimental dogs throughout the experimental period. Mean backscatter ratio was significantly increased (P = 0.02) by day 10. Uncorrected pixel intensity of the liver in 2 experimental dogs was approximately equal to that of the spleen on day 10 and greater than that of the spleen on day 14.

Conclusion

Administration of prednisone to dogs results in increased acoustic backscatter and attenuation in the liver.

Clinical Relevance

The video signal method is a sensitive technique for detecting subtle acoustic changes in the liver of dogs. (Am J Vet Res 1996;57:1690–1694)

Free access
in American Journal of Veterinary Research

Summary

Adrenocortical tumors were diagnosed in 5 adult spayed ferrets. Four ferrets had bilaterally symmetrical alopecia of the caudal femoral region, abdomen, and tail, and 1 had alopecia of the distal limbs and feet. All 5 ferrets had vulvar swelling. During abdominal ultrasonography, irregular masses, believed to involve the adrenal glands, were seen in all 5 ferrets. Unilateral adrenalectomy was performed successfully in each ferret by use of ventral midline celiotomy. On histologic examination of biopsy samples, 4 ferrets were found to have adrenocortical adenomas, and 1 ferret was found to have an adrenocortical adenocarcinoma. All clinical signs resolved after adrenalectomy, suggesting that the adrenocortical tumors had been secreting adrenocortical hormones.

Free access
in Journal of the American Veterinary Medical Association

Abstract

OBJECTIVE

To evaluate a novel 2-catheter technique for urethral catheterization in female cats and small dogs and compare the time required for and success rates achieved by use of the novel technique versus traditional methods (blind technique in cats and digital palpation in dogs) as performed by personnel (catheter placers [CPs]) with different levels of experience in urinary catheter placement.

ANIMALS

39 healthy sexually intact female animals (24 cats and 15 dogs weighing < 10 kg).

PROCEDURES

2 CPs were board certified in veterinary surgery, 1 of whom had experience with the novel technique, and the other did not. The third CP was a veterinary surgical intern who was unfamiliar with the novel technique. For each animal enrolled in the study, 1 CP performed catheterization with the novel technique and traditional methods. Data recorded included the time required for successful catheterization and whether a successful catheterization was achieved within a 3-minute time limit.

RESULTS

The overall success rates were 79.5% (31/39 animals) with the novel technique and 43.6% (17/39 animals) with traditional methods. Median times for successful catheter placement were 48 seconds for the novel technique and 41 seconds for traditional methods. Among CPs, success rates or times to successful catheter placement did not differ significantly.

CONCLUSIONS AND CLINICAL RELEVANCE

Study results suggested that the novel 2-catheter technique for urethral catheterization may be a more efficient option than traditional methods for gaining access to the urinary bladder in cats and small dogs, particularly when patient size limits use of instrumentation or digital palpation.

Full access
in American Journal of Veterinary Research

Abstract

OBJECTIVE To evaluate pharmacokinetic and pharmacodynamic characteristics of 3 doses of tapentadol hydrochloride orally administered in dogs.

ANIMALS 6 healthy adult mixed-breed dogs.

PROCEDURES In a prospective, randomized crossover study, dogs were assigned to receive each of 3 doses of tapentadol (10, 20, and 30 mg/kg, PO); there was a 1-week washout period between subsequent administrations. Plasma concentrations and physiologic variables were measured for 24 hours. Samples were analyzed by use of high-performance liquid chromatography–tandem mass spectrometry.

RESULTS Tapentadol was rapidly absorbed after oral administration. Mean maximum plasma concentrations after 10, 20, and 30 mg/kg were 10.2, 19.7, and 31 ng/mL, respectively. Geometric mean plasma half-life of the terminal phase after tapentadol administration at 10, 20, and 30 mg/kg was 3.5 hours (range, 2.7 to 4.5 hours), 3.7 hours (range, 3.1 to 4.0 hours), and 3.7 hours (range, 2.8 to 6.5 hours), respectively. Tapentadol and its 3 quantified metabolites (tapentadol sulfate, tapentadol-O-glucuronide, and desmethyltapentadol) were detected in all dogs and constituted 0.16%, 2.8%, 97%, and 0.04% of the total area under the concentration-time curve (AUC), respectively. Plasma AUCs for tapentadol, tapentadol sulfate, and tapentadol-O-glucuronide increased in a dose-dependent manner. Desmethyltapentadol AUC did not increase in a linear manner at the 30-mg/kg dose. Sedation scores and heart and respiratory rates were not significantly affected by dose or time after administration.

CONCLUSIONS AND CLINICAL RELEVANCE Oral administration of tapentadol was tolerated well, and the drug was rapidly absorbed. Adverse events were not apparent in any dogs at any doses in this study.

Full access
in American Journal of Veterinary Research
in Journal of the American Veterinary Medical Association

Abstract

Objective

To examine the toxic effects of fumonisin B1 (FB1(-containing culture material and deoxynivalenol (DON)-contaminated wheat diets on barrows.

Animals

24, 7-week-old crossbred barrows allotted to 4 equal groups of 3 replicates of 2 barrows/replicate.

Procedure

Barrows were fed diets for 28 days that were formulated as follows: no additional FCM or DON/kg of feed (control); 100 mg FB1/kg of feed; 5 mg DON/kg of feed; or 100 mg FB1 plus 5 mg DON/kg of feed. Body weight and feed consumption were monitored weekly. On day 28, blood samples were obtained for serum biochemical, hematologic, and immunologic measurements. On day 29, barrows were euthanatized and necropsies were performed.

Results

Analyzed mycotoxin content of diets were: none detected (control); 47 mg of FB1/kg of feed (FB1 diet); 4.5 mg of DON/kg of feed (DON diet); and 56 mg of FB1 and 3.7 mg of DON/kg of feed (FB1 plus DON diet). Differences were detected among groups of barrows for clinical performance, serum biochemical analytes, immunologic response, and histopathologic lesions.

Conclusions

Combining FB1-containing material and DON-contaminated wheat in the diets of growing barrows induces a more toxic response than that induced by either toxin singly. For many variables, the response could be described as additive; however, for some variables, responses were interactive in a greater-than-additive manner.

Clinical Relevance

Caution should be exercised when formulating swine diets that could contain FB1 and DON, because the condition induced by their combination is more severe than that predicted for each mycotoxin's toxicity. (Am J Vet Res 1996;57:1790–1794)

Free access
in American Journal of Veterinary Research

Abstract

OBJECTIVE

To describe long-term outcomes of cats managed medically for cranial cruciate ligament disease (CCLD) via a validated owner-based questionnaire.

ANIMALS

18 client-owned cats.

PROCEDURES

Retrospective review of medical records at 2 tertiary referral hospitals was conducted for records of cats diagnosed with CCLD for which medical management was pursued. History, physical examination findings, and medical management strategies were recorded. Owner follow-up was obtained via phone call or an email correspondence interview using a 2-part questionnaire. Part 1 consisted of 5 multiple-choice questions evaluating short-term outcomes following initiation of medical management. Part 2 assessed long-term outcomes via the validated Feline Musculoskeletal Pain Index—short form metrology instrument.

RESULTS

Mean follow-up time was 66.5 ± 46.7 months (range, 7 to 154 months). Medical management included oral analgesics, activity restriction, and joint supplements. Of the 18 cats, 13 (72%) were always able to bear weight or became weight bearing within a week following initiation of medical management, and 15 (83%) were reportedly clinically normal within 3 months of initiating medical management, with complete resolution of lameness occurring in less than 2 months in 12 of those cats. Long term, 17 of the 18 (94%) owners reported they felt that their cat had a good to excellent outcome with medical management. The mean Feline Musculoskeletal Pain Index—short form score of all cats was 0.29 ± 0.53 (range, 0 to 2.13).

CLINICAL RELEVANCE

Based on owner follow-up, conservative, nonsurgical management of CCLD can be an effective and appropriate management strategy for some cats; however, some may be best treated with surgical stabilization.

Full access
in Journal of the American Veterinary Medical Association

Abstract

OBJECTIVE

Assess the accuracy of predicted daily energy requirement (pDER) reported by a triaxial accelerometer and activity monitor for dogs (FitBark 2; FitBark Inc) and determine whether the activity monitor accurately estimates the observed daily energy requirement (oDER). We hypothesized that the activity monitor would accurately estimate oDER in dogs and meet standards established for human devices.

ANIMALS

23 dogs between the ages of 1 and 10 years and variable sex, breed, and body weight were enrolled from May 5, 2021, through July 23, 2021.

METHODS

Dogs were weighed before and after the study period to ensure stable body weights. Owners recorded their dogs’ daily caloric intake for the entire 28-day study period while the device monitored physical activity and calculated pDER. oDER was defined as the reported caloric intake required to maintain a stable body weight over a 28-day period. pDER and oDER were compared using Bland-Altman graphs, Passing-Bablock analysis, and Lin’s Concordance correlation analysis. P ≤ .05 was considered significant.

RESULTS

23 apparently healthy dogs completed the study. There was no significant difference between starting body weights and ending body weights (P= .5). The activity monitor overpredicted 28-day pDER compared to 28-day oDER in the majority (18/23, 78.3%) of dogs. Based on Bland-Altman analysis, Passing-Bablok regression, and Lin’s concordance correlation analysis, there was poor agreement between the pDER and oDER.

CLINICAL RELEVANCE

The activity monitors consistently reported inaccurate pDER compared to oDER. Its usability for estimating pDER is of limited clinical and research utility based on the results of this study.

Open access
in American Journal of Veterinary Research