Search Results

You are looking at 31 - 37 of 37 items for

  • Author or Editor: Daniel Ward x
  • Refine by Access: All Content x
Clear All Modify Search

Abstract

Objective—To evaluate the effect of frequent milkout (FMO) on the outcome of experimentally induced Escherichia coli mastitis in cows.

Design—Randomized complete block study.

Animals—16 Holstein dairy cows.

Procedure—Cows were randomly assigned to 1 of 4 groups and were either not infected and not treated (NI-NT), experimentally infected with E coli and not treated (EC-NT), not infected and FMO (NI-FMO), or experimentally infected with E coli and FMO (EC-FMO). The infected quarter in cows in FMO groups was milked out every 4 hours from 16 to 36 hours and every 6 hours from 36 to 84 hours after challenge, with the aid of oxytocin administration. Somatic cell counts (SCC); times to bacterial, clinical, and systemic cures; and serum concentrations of α-lactalbumin were determined.

Results—Use of FMO did not appear to affect SCC. For EC-NT and EC-FMO groups, mean bacterial cure times were 203 and 159 hours, clinical cure times were 276 and 360 hours, and systemic cure times were 144 and 159 hours, respectively; these times were not significantly different. Concentrations of α-lactalbumin were significantly increased in the EC-NT group at 12 hours and in the NI-FMO group at 36 and 60 hours after challenge, compared with values of cows in other treatment groups.

Conclusions and Clinical Relevance—Compared with results in control cows, FMO does not appear to be an efficacious treatment for experimentally induced moderate to severe E coli mastitis. (J Am Vet Med Assoc 2003;222:63–66)

Full access
in Journal of the American Veterinary Medical Association

Abstract

OBJECTIVE

To document ocular findings in cats with blastomycosis.

ANIMALS

35 cats with blastomycosis.

PROCEDURES

Medical records from 1978 through 2019 were reviewed to identify cats with confirmed Blastomyces infection. Cats were grouped as having or not having ocular involvement. Clinical signs, histopathologic findings, and response to treatment were evaluated.

RESULTS

21 of the 35 (60%) cats with confirmed blastomycosis had ocular abnormalities. Two of 21 cats with ocular abnormalities also had systemic hypertension and were excluded. Of the remaining 19 cats, 15 (79%) had bilateral ocular signs. Ten (53%) cats had inflammatory ocular lesions, and 9 (47%) had neuro-ophthalmic abnormalities. Six of the 19 (32%) cats appeared to be completely blind, and 5 (26%) appeared to be unilaterally blind. For the 10 cats with inflammatory ocular lesions, the most common lesions were anterior uveitis (9/20 eyes), active chorioretinitis (6/20 eyes), and retinal detachment (4/20 eyes). For the 9 cats with neuro-ophthalmic abnormalities, the most common abnormalities were a negative menace or tracking response (10/18 eyes) and negative pupillary light response (4/18 eyes).

CLINICAL RELEVANCE

Results suggested that ocular involvement is common in cats with blastomycosis and that both inflammatory lesions and neuro-ophthalmic abnormalities can be seen. Blastomycosis should be considered in the differential diagnosis for cats with anterior uveitis, posterior segment inflammation, or neuro-ophthalmic abnormalities, and a complete ophthalmic examination should be performed in all cats with confirmed or suspected blastomycosis.

Full access
in Journal of the American Veterinary Medical Association

Abstract

Objective—To determine whether pharmacokinetic analysis of data derived from a single IV dose of iohexol could be used to predict creatinine clearance and evaluate simplified methods for predicting serum clearance of iohexol with data derived from 2 or 3 blood samples in clinically normal foals.

Animals—10 healthy foals.

Procedure—Serum disposition of iohexol and exogenous creatinine clearance was determined simultaneously in each foal (5 males and 5 females). A 3-compartment model of iohexol serum disposition was selected via standard methods. Iohexol clearance calculated from the model was compared with creatinine clearance. Separate limited-sample models were created with various combinations of sample times from the terminal slope of the plasma versus time profile for iohexol. Correction factors were determined for the limited-sample models, and iohexol clearance calculated via each method was compared with exogenous creatinine clearance by use of method comparison techniques.

Results—Mean exogenous creatinine clearance was 2.17 mL/min/kg. The disposition of iohexol was best described by a 3-compartment open model. Mean clearance value for iohexol was 2.15 mL/min/kg and was not significantly different from mean creatinine clearance. A method for predicting serum iohexol clearance based on a 2-sample protocol (3- and 4-hour samples) was developed.

Conclusions and Clinical Relevance—Iohexol clearance can be used to predict exogenous creatinine clearance and can be determined from 2 blood samples taken after IV injection of iohexol. Appropriate correction factors for adult horses and horses with abnormal glomerular filtration rate need to be determined. (Am J Vet Res 2003;64:1486–1490)

Full access
in American Journal of Veterinary Research

Abstract

Case Description—A 7-month-old 16.6-kg (36.5-lb) sexually intact female Golden Retriever was evaluated because of progressive severe bilateral membranous conjunctivitis, oral lesions, nasal discharge, and cough.

Clinical Findings—Histologic examination of conjunctival biopsy specimens revealed findings consistent with ligneous conjunctivitis. Circulating plasminogen activity was repeatedly low, and congenital plasminogen deficiency was identified as the underlying cause of the ocular, oral, and respiratory lesions.

Treatment and Outcome—Topical and subconjunctival administrations of fresh frozen plasma (FFP), topical administration of cyclosporine, and oral administration of azathioprine had no effect on the conjunctival membranes. Excision of the membranes followed by intensive treatment with topical applications of heparin, tissue plasminogen activator, corticosteroid, and FFP and IV administration of FFP prevented membrane regrowth. Intravenous administration of FFP increased plasma plasminogen activity to within reference limits, improved respiratory and oral lesions, and resulted in weight gain; discontinuation of this treatment resulted in weight loss, signs of depression, and worsening of lesions. After euthanasia because of disease progression, necropsy findings included mild hydrocephalus; multifocal intestinal hemorrhages; and fibrinous plaques in the oral cavity, nasopharynx, trachea, esophagus, and pericardium. Microscopically, the plaques were composed of fibrin and poorly organized granulation tissue. Fibrin thrombi were present within vessels in the lungs, oral cavity, and trachea.

Clinical Relevance—In dogs, congenital plasminogen deficiency can occur and may be the underlying cause of ligneous conjunctivitis. A combination of surgical and medical treatments may improve conjunctival membranes, and administration of FFP IV appears to be effective in treating nonocular signs of plasminogen deficiency.

Full access
in Journal of the American Veterinary Medical Association

Abstract

Objective—To determine whether antibodies against Sarcocystis neurona could be detected in CSF from clinically normal neonatal (2 to 7 days old) and young (2 to 3 months old) foals.

Design—Prospective study.

Animals—15 clinically normal neonatal Thoroughbred foals.

Procedure—Serum and CSF samples were obtained from foals at 2 to 7 days of age and tested for antibodies against S neurona by means of western blotting. Serum samples from the mares were also tested for antibodies against S neurona. Additional CSF and blood samples were obtained from 5 foals between 13 and 41 days after birth and between 62 and 90 days after birth.

Results—Antibodies against S neurona were detected in serum from 13 mares and their foals; antibodies against S neurona were detected in CSF from 12 of these 13 foals. Degree of immunoreactivity in serum and CSF decreased over time, and antibodies against S neurona were no longer detected in CSF from 2 foals 83 and 84 days after birth. However, antibodies could still be detected in CSF from the other 3 foals between 62 and 90 days after birth.

Conclusions and Clinical Relevance—Results indicate that antibodies against S neurona can be detected in CSF from clinically normal neonatal (2 to 7 days old) foals born to seropositive mares. This suggests that western blotting of CSF cannot be reliably used to diagnose equine protozoal myeloencephalitis in foals < 3 months of age born to seropositive mares. (J Am Vet Med Assoc 2002;220:208–211)

Full access
in Journal of the American Veterinary Medical Association

Abstract

Objective—To evaluate antiplatelet effects and pharmacodynamics of clopidogrel in cats.

Design—Original study.

Animals—5 purpose-bred domestic cats.

Procedure—Clopidogrel was administered at dosages of 75 mg, PO, every 24 hours for 10 days; 37.5 mg, PO, every 24 hours for 10 days; and 18.75 mg, PO, every 24 hours for 7 days. In all cats, treatments were administered in this order, with at least 2 weeks between treatments. Platelet aggregation in response to ADP and collagen and oral mucosal bleeding times (OMBTs) were measured before and 3, 7, and 10 days (75 and 37.5 mg) or 7 days (18.75 mg) after initiation of drug administration. Serotonin concentration in plasma following stimulation of platelets with ADP or collagen was measured before and on the last day of drug administration. Platelet aggregation, OMBT, and serotonin concentration were evaluated at various times after drug administration was discontinued to determine when drug effects were lost.

Results—For all 3 dosages, platelet aggregation in response to ADP, platelet aggregation in response to collagen, and serotonin concentration were significantly reduced and OMBT was significantly increased at all measurement times during drug administration periods. All values returned to baseline values by 7 days after drug administration was discontinued. No significant differences were identified between doses. None of the cats developed adverse effects associated with drug administration.

Conclusions and Clinical Relevance—Results suggest that administration of clopidogrel at dosages ranging from 18.75 to 75 mg, PO, every 24 hours, results in significant antiplatelet effects in cats. (J Am Vet Med Assoc 2004;225:1406–1411)

Full access
in Journal of the American Veterinary Medical Association

Abstract

In collaboration with the American College of Veterinary Pathologists

Open access
in Journal of the American Veterinary Medical Association