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Summary

Plasma von Willebrand factor antigen concentration was measured in 10 dogs with hypothyroidism, before and after administration of a replacement dose of levothyroxine for 67 ± 12 days. Results were reported as a percentage of normal activity, with plasma pooled from clinically normal dogs given a value of 100%. Plasma von Willebrand factor antigen concentration was within reference limits in dogs with hypothyroidism (126 ± 41%) and was significantly (P < 0.01) decreased (94 ± 39%) after treatment with levothyroxine. Contrary to findings in some other studies, a deficiency of plasma von Willebrand factor did not appear to result from hypothyroidism.

Free access
in Journal of the American Veterinary Medical Association

Abstract

OBJECTIVE

To evaluate the efficacy of IV administration of apomorphine for removal of gastric foreign bodies in dogs.

ANIMALS

495 dogs with gastric foreign bodies.

PROCEDURES

Records of a veterinary hospital were searched to identify dogs that received an injectable formulation of apomorphine between January 1, 2010, and July 30, 2015. Dogs with a gastric foreign body that received an IV injection of apomorphine were included in the study. Information extracted from the record of each dog included signalment, type of foreign material ingested, duration between foreign material ingestion and emesis, dose and number of doses of apomorphine administered, and whether emesis occurred and did or did not result in successful removal of the foreign body. Descriptive data were compared between dogs with and without successful foreign body removal.

RESULTS

Emesis with successful foreign body removal was achieved in 363 and 11 dogs after administration of 1 and 2 doses of apomorphine, respectively. Successful removal was more likely for young dogs and dogs that had ingested fabric, leather, or bathroom waste. Successful removal was less likely as the duration between foreign body ingestion and emesis increased and for dogs that received opioids, sedatives, or antiemetics before apomorphine administration. Minor adverse effects were recorded for only 4 dogs.

CONCLUSIONS AND CLINICAL RELEVLANCE

IV administration of apomorphine was a viable alternative for induction of emesis and removal of gastric foreign bodies in dogs. Dogs should be examined as soon as possible after foreign body ingestion and should not receive any medications that might affect apomorphine efficacy.

Full access
in Journal of the American Veterinary Medical Association

Abstract

Objective—To characterize lysosomal storage body accumulation in the retina and brain of Tibetan Terriers with ceroid-lipofuscinosis and determine whether the disease in these dogs is accompanied by impaired retinal function and retinal degeneration.

Animals—Three 7- to 10-year-old Tibetan Terriers with ceroid-lipofuscinosis and 1 healthy 5-year-old Tibetan Terrier.

Procedure—Owners completed a questionnaire to identify behavioral and physical signs indicative of ceroid-lipofuscinosis. Neurologic, behavioral, and ophthalmologic evaluations, including full-field electroretinograms, were performed on each dog. Fluorescence, light, and electron microscopy were performed on specimens of retina, cerebral cortex, and cerebellum of all dogs postmortem.

Results—Behavioral assessments of the affected dogs revealed moderate visual impairment in lowlight conditions but good vision in bright light. On funduscopic evaluation of these dogs, abnormalities detected ranged from none to signs of moderately advanced retinal degeneration. Compared with findings in the control dog, electroretinography revealed depressed rod cell function with some impairment of cone cell function in the affected dogs. Morphologically, disease-specific storage bodies were detected in retinal Müller cells and neurons, particularly in ganglion cells, and in cells of the cerebral cortex and cerebellum in affected dogs. Substantial photoreceptor cell loss and disruption of photoreceptor outer segment morphology appeared to develop late in the disease.

Conclusions and Clinical Relevance—The similarities between ceroid-lipofuscinosis in Tibetan Terriers and some forms of ceroid-lipofuscinosis in humans suggest that the canine disease may have a genetic and biochemical basis similar to that of one of the ceroidlipofuscinosis disorders in humans. (Am J Vet Res 2005;66:67–76)

Full access
in American Journal of Veterinary Research

SUMMARY

Canine and human platelets (washed 4 times in a solution containing edta, prostaglandin E1, and theophylline to prevent release of agranule constituents) were lysed by being frozen and thawed in the presence of detergent. Radioelectroimmunoassay for von Willebrand factor (vWf) in 5 human platelet lysates produced precipitin rockets, shaped like those produced from vWf in plasma from healthy human beings, and indicated that the mean von Willebrand factor antigen (vWf:Ag) content in platelets from healthy human beings was 526 ± 87 human U/ 1012 platelets. Radioelectroimmunoassay for vWf in platelet lysates from 17 healthy dogs with normal plasma vWf:Ag concentration produced precipitin rockets that looked different from those produced from canine plasma and indicated vWfAg content of 59 ± 35 canine U/1012 platelets. Inclusion of protease inhibitors in the lysing solution did not normalize the appearance of the precipitin rockets or substantially alter the measured platelet content of vWf:Ag. The array of vWf multimers revealed by sodium dodecyl sulfate-agarose gel electrophoresis of canine platelet lysates had a distinct appearance that differed from that of vWf in canine or human plasma and platelets; the intensity of the canine platelet vWf multimer bands was skewed, with relatively greater density in the lower molecular weight region and faint or undetectable multimer bands in the higher molecular weight region. Electrophoretograms with visible multimers in the high molecular weight region had vWf components that had higher molecular weight than did any vWf components in canine plasma. Radioelectroimmunoassay for fibronectin in these same canine platelet lysates indicated that the fibronectin content in platelets was 2.89 ± 1.10 mg/1012 platelets. An Airedale Terrier with type-I von Willebrand disease (vWd), but lacking clinical signs of vWd, had normal platelet content of vWf:Ag (28 ± 12 canine U/1012 platelets), whereas a German Shorthaired Pointer with moderately severe type-II vWd and a mildly affected Doberman Pinscher with type-I vWd had only a trace or undetectable amounts of vWf:Ag in their platelets. The concentration of vWf: Ag in platelet lysates from the Doberman Pinscher with vWd remained undetectable when the platelets were isolated from the Doberman Pinscher's blood mixed with citrated plasma from dogs with normal plasma vWf:Ag concentration. In all 3 dogs with vWd, platelet fibronectin content was within the normal range.

Free access
in American Journal of Veterinary Research

Abstract

Objective—To determine whether the late onset form of inherited ceroid lipofuscinosis (CL) in Tibetan Terriers is accompanied by low plasma carnitine concentrations prior to the appearance of clinical signs.

Animals—129 healthy Tibetan Terriers, 12 Tibetan Terriers with CL, and 95 healthy purebred dogs of other breeds.

Procedure—After withholding food, blood samples were collected from all dogs into tubes containing EDTA. Blood samples were analyzed for plasma-free carnitine and acyl-carnitines concentrations.

Results—Neither the mean plasma total carnitine concentration nor the mean fraction of carnitine in the free form differed significantly between Tibetan Terriers with CL and healthy Tibetan Terriers. Among Tibetan Terriers and the general dog population, plasma carnitine concentration increased with age. Castrated males had an overall increase in plasma carnitine concentrations and variability, compared with sexually intact males. By comparison, plasma carnitine concentrations were not significantly different between spayed and sexually intact females. The mean plasma carnitine concentration in the Tibetan Terriers was approximately 22% higher than in the general population of healthy dogs of other breeds.

Conclusion and Clinical Relevance—Contrary to what is seen in early onset CL in English Setters and in humans with some forms of CL, plasma carnitine concentrations are not decreased in the late-onset disorder in Tibetan Terriers. Our large-scale study establishes reference range values for plasma carnitine concentrations in dogs as functions of age and sex that will be useful in evaluating potential carnitine deficiencies in other disorders in dogs. (Am J Vet Res 2002;63:890–895)

Full access
in American Journal of Veterinary Research

Abstract

Objective—To determine clinical characteristics and mode of inheritance of idiopathic epilepsy (IE) in English Springer Spaniels.

Design—Original study.

Animals—45 dogs with IE and 74 siblings and their respective parents.

Procedure—IE was diagnosed on the basis of age at the time of seizure onset and results of laboratory testing and neurologic examinations. Simple segregation analysis was performed with the Davie method.

Results—Median age at the onset of seizures was 3 years; however, 9 (20%) dogs were between 5 and 6 years old at the time of the onset of seizures. Twentyone dogs (47%) had generalized seizures, and 24 (53%) had focal onset seizures. Results of segregation analysis were consistent with partially penetrant autosomal recessive or polygenic inheritance. Simulated linkage indicated that there was a 58% chance of obtaining suggestive linkage with the available pedigrees.

Conclusions and Clinical Relevance—Results of the present study suggest that in English Springer Spaniels, IE segregates in a manner that is consistent with partially penetrant autosomal recessive inheritance (ie, a single major locus with modifying genes) or polygenic inheritance. Given enough families with accurate phenotypic information and available DNA, it should be possible to use genetic linkage analysis to identify chromosomal segments containing the causative gene or genes. (J Am Vet Med Assoc 2005;226:54–58)

Full access
in Journal of the American Veterinary Medical Association

Summary

A closely inbred line of Chow Chows affected with congenital cataracts was studied. Sixteen dogs were examined including 1 adult male, 2 adult females, and 13 pups. Twelve of the pups were from 6 different litters, out of 6 different bitches, all sired by 1 adult male. The exact relationship of the thirteenth pup was undetermined. Clinical evaluation included slit-lamp biomicroscopy, biomicroscopic photography, and indirect ophthalmoscopy. Clinical appearance of the cataracts was variable, ranging from incipient nuclear or capsular lesions to advanced cortical opacity. The lens nucleus was most consistently affected, with variable involvement of the lens cortex. Concurrent ocular anomalies of some eyes included wandering nystagmus, entropion, microphthalmia, persistent pupillary membrane remnants, and multifocal retinal folds. A correlation was not apparent between the character or severity of the cataracts and the fnding of the other anomalies. Histologic examination of 12 lenses revealed posterior displacement of the lens nucleus, retained lens epithelial cell nuclei in the nuclear and cortical lens, anterior capsular irregularity and duplication, anterior lens epithelial duplication, and posterior subcapsular migration of epithelium. The high incidence of cataract in this family of Chow Chows suggested an inherited defect, although the inheritance pattern was undetermined.

Free access
in Journal of the American Veterinary Medical Association

SUMMARY

The effects of hypertonic saline solution (htss) combined with colloids on hemostatic analytes were studied in 15 dogs. The analytes evaluated included platelet counts, one-stage prothrombin time, activated partial thromboplastin time, von Willebrand's factor antigen (vWf:Ag), and buccal mucosa bleeding times. The dogs were anesthetized, and jugular phlebotomy was used to induce hypovolemia (mean arterial blood pressure = 50 mm of Hg). Treatment dogs (n = 12) were resuscitated by infusion (6 ml/kg of body weight) of 1 of 3 solutions: htss combined with 6% dextran 70, 6% hetastarch, or 10% pentastarch. The control dogs (n = 3) were autotransfused. Hemostatic analytes were evaluated prior to induction of hypovolemia (baseline) and then after resuscitation (after 30 minutes of sustained hypovolemia) at 0.25, 0.5, 1, 6 and 24 hours.

All treatment dogs responded rapidly and dramatically to resuscitation with hypertonic solutions. Clinically apparent hemostatic defects (epistaxis, petechiae, hematoma were not observed in any dog. All coagulation variables evaluated, with the exception of vWf:Ag, remained within reference ranges over the 24-hour period. The vWf:Ag values were not statistically different than values from control dogs, and actual values were only slightly lower than reference ranges. Significant (P ≤ 0.04) differences were detected for one-stage prothrombin time, but did not exceed reference ranges. The results of this study suggested that small volume htss/colloid solutions do not cause significant alterations in hemostatic analytes and should be considered for initial treatment of hypovolemic or hemorrhagic shock.

Free access
in American Journal of Veterinary Research

Abstract

Objective

To evaluate efficacy of florfenicol treatment for bovine mastitis caused by Streptococcus agalactiae, Staphylococcus aureus, nonagalactiae streptococci, coagulase-negative staphylococci, Escherichia coli, Klebsiella sp, and others.

Design

Double blind study with cases randomly assigned to 1 of 2 treatment groups.

Sample Population

861 cows/10 commercial dairy farms.

Procedures

Experimental (750 mg of florfenicol) or control (200 mg of cloxacillin) treatment was administered by intramammary infusion every 12 hours for 3 treatments to all cases. Treatments were randomly assigned, identified only by numerical labels. To retain blinding, the longer withdrawal time was adhered to for all cases. Cases remained in the study only if there was no other treatment. Quarter samples were recultured 14, 21, and 28 days later. If all samples after day 1 were culture negative, the case was defined as cured. If only 1 of the follow-up results was positive, the case was considered cured if the day-28 somatic cell count was < 300,000/ml. Failure of treatment was defined as 2 or more culture-positive follow-up samples.

Results

Florfenicol and cloxacillin did not differ significantly in efficacy versus clinical (n = 85) or subclinical (n = 71) bovine mastitis, or for any etiologic agent (χ2). Overall cure rates for mastitis were: Str agalactiae, 5 of 8 (63%); Sta aureus, 5 of 54 (9%); Streptococcus sp, 16 of 35 (46%); Staphylococcus sp, 7 of 33 (21 %); E coli, 5 of 11 (46%); Klebsiella sp, 3 of 6 (50%); others, 1 of 9 (11%); and all cases, 42 of 156 (27%).

Conclusions

Florfenicol did not offer any advantage over cloxacillin in efficacy against bovine mastitis. Overall cure rates were low. As with most mastitis treatment regimens, poor efficacy may be partly attributable to the short duration of treatment. (Am J Vet Res 1996;57:526–528)

Free access
in American Journal of Veterinary Research