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in Journal of the American Veterinary Medical Association
in Journal of the American Veterinary Medical Association
in Journal of the American Veterinary Medical Association

Objective

To determine outcome for foals with incomplete ossification of the tarsal bones and to determine whether clinical and radiographic abnormalities at the time of initial examination were associated with outcome.

Design

Retrospective study.

Animals

22 foals.

Procedure

Information on signalment, history, owner’s initial complaint, clinical findings, whether tarsus valgus was evident, and radiographic abnormalities was obtained from medical records. Radiographic lesions were classified as type I (ie, incomplete ossification with < 30% collapse of the affected bones) or type II (incomplete ossification with > 30% collapse and pinching or fragmentation of the affected bones). Follow-up information was obtained via telephone conversations with owners.

Results

Foals were between 1 day and 10 months old when first examined. Eleven were premature (ie, < 320 days of gestation) or were twins. Sixteen had tarsus valgus. Severity of radiographic lesions was associated with outcome; 4 of 6 foals with type-I incomplete ossification of the tarsal bones performed as intended, but only 3 of 16 foals with type-II incomplete ossification of the tarsal bones performed as intended.

Clinical Implications

For foals with incomplete ossification of the tarsal bones, severity of the radiographic lesions was associated with outcome. Foals with type-II incomplete ossification of the tarsal bones have a guarded prognosis for athletic soundness. (J Am Vet Med Assoc 1998;213:1590–1594)

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in Journal of the American Veterinary Medical Association
in Journal of the American Veterinary Medical Association

SUMMARY

The kinetics of specific IgM and IgG antibody response was characterized in four 9-month-old Beagles after inoculation of 2 × 102 plaque-forming units (pfu) of Sheila Smith strain of Rickettsia rickettsii. Immunoglobulin M antibodies were first detected by indirect immunoflorescence on postinoculation (pi) day 9, peaked by pi day 20, and were no longer detectable by pi day 80. Immunoglobulin G antibodies became detectable between pi days 22 and 28, peaked by pi day 42, and decreased gradually through pi day 130. Subsequent challenges with R rickettsii on pi days 216 (2 × 102 pfu/dog) and 1,029 (5 × 104 tissue culture infective dose [tcid 50]/dog) resulted in slightly different serologic responses. The initial challenge exposure failed to increase the concentration of IgG antibodies and induced only low concentrations of IgM antibodies. After the second challenge inoculation, IgM antibodies were not detectable and the concentration IgG antibodies increased slightly. Clinical abnormalities and seroconversion were documented in control dogs following each challenge exposure.

Examination of acute and convalescent serum samples from 55 dogs in which Rocky Mountain spotted fever was suspected clinically suggested that sole evaluation of IgM antibodies in acute-phase serum would result in inaccurate diagnoses because of false-positive and -negative results. Use of a composite conjugate that detects IgM and IgG antibodies to R rickettsii appears to be satisfactory for diagnostic purposes; however, concurrent quantitation of IgM antibodies may facilitate serodiagnosis in a select group of dogs in which a four-fold increase in convalescent antibody titer is not detected by use of the composite conjugate.

With the exception of a dog with a serum antibody titer of 1:8,192, we were unable to detect IgM or IgG antibodies in csf samples from 9 dogs with experimentally and 3 dogs with naturally acquired infections.

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in American Journal of Veterinary Research

Abstract

Objective—To evaluate the association between spondylosis deformans and clinical signs of intervertebral disk disease (IVDD) in dogs.

Design—Retrospective case series.

Animals—210 dogs.

Procedure—Records of 172 dogs with clinical signs of IVDD and 38 dogs with other neurologic disorders were reviewed. Signalment, sites of spondylosis, severity of associated osteophytosis, type of disk herniation, and duration of signs were recorded.

Results—Dogs with IVDD had significantly fewer sites of involvement and lower grades of spondylosis deformans, compared with those in the non-IVDD group. When groups were adjusted for age and weight via multivariate linear regression, there were no differences in severity of osteophytosis or number of affected sites. Dogs with type II disk disease had higher numbers of affected sites and more severe changes, compared with dogs with type I disk herniation. There was no difference between groups in the rate at which IVDD was diagnosed at sites of spondylosis, compared with the rate at which IVDD was diagnosed in unaffected disk spaces. Areas of spondylosis were closer to sites of IVDD that elicited clinical signs than to randomly chosen intervertebral spaces, and distances between sites of spondylosis and sites of IVDD had a bimodal appearance.

Conclusions and Clinical Relevance—An association may exist between radiographically apparent spondylosis and type II disk disease; type I disk disease was not associated with spondylosis. Spondylosis in radiographs of dogs with suspected type I disk disease is not clinically important. Spatial associations among sites of spondylosis and sites of IVDD may be coincidental or associated with vertebral column biomechanics.

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in Journal of the American Veterinary Medical Association

Abstract

Objective—To evaluate the correlation between halftime of liquid-phase gastric emptying (T50), determined with nuclear scintigraphy using technetium Tc 99m pentetate, and absorption variables of orally administered acetaminophen.

Animals—6 mature horses.

Procedure—Technetium Tc 99m pentetate (10 mCi) and acetaminophen (20 mg/kg of body weight) were administered simultaneously in 200 ml of water. Serial left and right lateral images of the stomach region were obtained with a gamma camera, and T50 determined separately for counts obtained from the left side, the right side and the geometric mean. Power exponential curves were used for estimation of T50 and modified R2 values for estimation of goodness of fit of the data. Serial serum samples were taken, and acetaminophen concentration was determined, using fluorescence polarization immunoassay. Maximum serum concentration (Cmax), time to reach maximum serum concentration (Tmax), area under the curve for 240 minutes and the absorption constant (Ka) were determined, using a parameter estimation program. Correlations were calculated, using the Spearman rank correlation coefficient.

Results—Correlations between T50 and Tmax and between T50 and Ka were significant.

Conclusions and Clinical Relevance—Tmax and Ka are valuable variables in the assessment of liquidphase gastric emptying using acetaminophen absorption. Acetaminophen absorption may be a valuable alternative to nuclear scintigraphy in the determination of gastric emptying rates in equine patients with normally functioning small intestine. (Am J Vet Res 2000;61:310–315)

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in American Journal of Veterinary Research