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Objective—To define the vertical position of the patella in clinically normal large-breed dogs.

Sample Population—Cadavers of 13 clinically normal large-breed dog.

Procedure—Both hind limbs were harvested with intact stifle joints and mounted on a positioning device that allowed full range of motion of the stifle joint. Lateral radiographic views were obtained with the stifle joints positioned at each of 5 angles (148°, 130°, 113°, 96°, and 75°). Vertical position of the patella through a range of motion was depicted on a graph of mean stifle angle versus corresponding mean proximal patellar position (PPP) and distal patellar position (DPP) relative to the femoral trochlea for each dog. Ratio of length of the patellar ligament to length of the patella (L:P) was determined for each dog. Overall mean, SD, and 95% confidence intervals for L:P were calculated for all dogs.

Results—Evaluation of vertical position of the patella through a range of motion revealed a nearly linear relationship between joint angle and PPP and joint angle and DPP. Evaluation of L:P results did not reveal significant differences between limbs (left or right) or among joint angles. Overall mean ± SD L:P for all dogs was 1.68 ± 0.18 (95% confidence interval, 1.33 to 2.03).

Conclusion and Clinical Relevance—The L:P proved to be a repeatable measurement of vertical patellar position, which is independent of stifle angles from 75° to 148°. This measurement could be used as a quantitative method for diagnosing patella alta and patella baja in large-breed dogs. (Am J Vet Res 2002;63:42–46)

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in American Journal of Veterinary Research


OBJECTIVE To quantify plasma concentrations and determine adverse ocular, renal, or hepatic effects associated with repeated topical ophthalmic application of 0.1% diclofenac to healthy cats.

ANIMALS 8 healthy sexually intact male cats.

PROCEDURES A randomized, placebo-controlled crossover study was conducted. A topical formulation of 0.1% diclofenac was administered 4 times/d for 7 days to 4 cats, and artificial tear (control) solution was administered to the other 4 cats. After a 12-day washout period, cats received the other treatment. Ophthalmic examinations were performed daily. Plasma samples were obtained on days 1 and 7 for pharmacokinetic analysis. A CBC, serum biochemical analysis, urinalysis, determination of urine protein-to-creatinine ratio, and determination of glomerular filtration rate were performed before the start of the study and after each 7-day treatment period.

RESULTS Mild conjunctival hyperemia was the only adverse ocular effect detected. Maximal drug concentration and area under the curve were significantly higher on day 7 than on day 1. Diclofenac-treated cats had a significantly lower glomerular filtration rate than did control-treated cats after the second but not after the first treatment period, presumably associated with iatrogenic hypovolemia.

CONCLUSIONS AND CLINICAL RELEVANCE Topical ophthalmic administration of 0.1% diclofenac was well tolerated in healthy cats, with only mild signs of ocular irritation. Detectable systemic concentrations of diclofenac were achieved with accumulation over 7 days. Systemic absorption of diclofenac may be associated with reduced glomerular filtration rate, particularly in volume-contracted animals. Topical ophthalmic 0.1% diclofenac should be used with caution in volume-contracted or systemically ill cats.

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in American Journal of Veterinary Research


Objective—To determine clinical and pathologic findings before and after short-term (group 1) and longterm (group 2) treatment in dogs with Hepatozoon americanuminfection.

Design—Retrospective study.

Animals—53 dogs with H americanuminfection.

Procedure—Medical records of dogs that were treated for hepatozoonosis diagnosed on the basis of meront or merozoite stages in skeletal muscle were reviewed.

Results—Circulating gametocytes of H americanum were identified in 12 of 53 dogs. Dogs were treated with various drugs, including toltrazuril, trimethoprimsulfadiazine, clindamycin, pyrimethamine, and decoquinate. Mean WBC counts prior to treatment were 85,700 and 75,200 cells/µl in groups 1 and 2, respectively, and 1 month after initiation of treatment were 12,600 and 14,600 cells/µl, respectively. Initial response to treatment was excellent in all dogs. Twenty-three of 26 dogs in group 1 relapsed at least once and died within 2 years; mean (± SD) survival time was 12.6 ± 2.2 months. Twenty-two of 27 group-2 dogs survived; 11 dogs had no clinical signs and were still receiving decoquinate (mean duration of treatment, 21 months), 11 dogs had no clinical signs after treatment for 14 months (range, 3 to 33 months; mean survival time, 39 months [range, 26 to 53 months]), 2 dogs were lost to follow-up, and 3 dogs were euthanatized because of severe disease.

Conclusions and Clinical Relevance—Although no treatment effectively eliminated the tissue stages of H americanum, treatment with trimethoprim-sulfadiazine, clindamycin, and pyrimethamine followed by long-term administration of decoquinate resulted in extended survival times and excellent quality of life. ( J Am Vet Med Assoc 2001;218:77–82)

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in Journal of the American Veterinary Medical Association