Search Results

You are looking at 1 - 10 of 14 items for

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

Abstract

Objective—To determine variations in cytologic counts of bronchoalveolar lavage (BAL) fluid attributable to month of collection, first and second aliquots, and left and right lung sites in horses with recurrent airway obstruction (RAO).

Animals—5 horses with RAO and 5 healthy horses without respiratory tract disease.

Procedures—Horses were housed in a stable for 5 months prior to and throughout the study. Bronchoalveolar lavage fluid was collected from the right and left lung of each horse 3 times at monthly intervals (February, March, and April). Each BAL fluid collection was performed by use of 2 incremental instillations of 250 mL of isotonic saline (0.9% NaCl) solution in the same bronchial site. Analysis of BAL fluid included volume of BAL fluid recovered, a CBC, and differential cytologic counts.

Results—Volume of BAL fluid recovered and cytologic counts did not differ in horses with RAO across time or between right and left lungs, except for the number of mast cells. Horses with RAO had significantly lower volumes of BAL fluid recovered, significantly lower percentages of macrophages and lymphocytes, and significantly higher percentages of neutrophils than did healthy horses. Despite individual variation, all horses with RAO had > 25% neutrophils throughout the study period.

Conclusions and Clinical Relevance—Despite variation among horses, BAL fluid cytologic counts were repeatable over short and long periods and samples can be used for longitudinal studies as a diagnostic tool of pulmonary inflammation in horses with RAO.

Full access
in American Journal of Veterinary Research

Abstract

Objectives

To determine temporal variations of pulmonary function in horses without respiratory tract disease (controls) and horses with chronic obstructive pulmonary disease (COPD) and determine whether reversibility of airway obstruction after environmental control can be predicted by response to atropine administration.

Animals

7 COPD-affected and 5 control horses.

Procedures

Pulmonary function testing was performed monthly during 3 consecutive months, daily for 5 consecutive days, and at 6-hour intervals for 24 hours before and after administration of atropine (0.02 mg/kg of body weight, IV) and after 5 consecutive months at pasture. Respiratory rate, tidal volume (VT), minute ventilation (VE), maximal change in transpulmonary pressure (ΔPL), pulmonary resistance (RL), and pulmonary elastance (EL) were calculated.

Results

COPD-affected horses had a significantly higher expiratory to inspiratory time ratio (TE/TI) and ΔPL, EL, and RL than horses without respiratory tract diseases during all periods and higher VE during monthly and daily evaluations. Daily variation in VT and monthly and circadian variation in EL were significant in COPD-affected horses. In control horses, significant changes were apparent only in TE/TI during daily recordings. In COPD-affected horses, reduction in ΔPL, RL, and EL was significant after atropine administration and after maintenance on pasture.

Conclusions and Clinical Relevance

Despite variations in measurements of respiratory mechanics in both groups of horses, values remained significantly different between groups over time. Despite individual variation, measurements were repeatable during short and long periods. Response to administration of atropine to COPD-affected horses underestimated improvement in respiratory tract function that resulted from maintenance on pasture. (Am J Vet Res 1999;60:1341–1346)

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

Summary

In 1989, 4,808 cases of rabies in animals other than human beings were reported to the Centers for Disease Control, 1.8% more (4,724 to 4,808) than in 1988. Eighty-eight percent (4,224/4,808) of those affected were wild animals and 12% (584/4,808) were domestic animals. Cases were reported from 49 states, the District of Columbia, and Puerto Rico; Hawaii remained rabies-free. Skunks (1,657) continued to be the most commonly reported rabid wild animal. For the second consecutive year, more cats (212) were reported to be infected with rabies virus than any other domestic species. Compared with their 1988 reports, 5 states reported increases of greater than 100% (Alaska, 109%; New Jersey, 233%; Ohio, 133%; Oklahoma, 168%; and Washington, 125%), and 5 states reported decreases of greater than 50% (Connecticut, 63%; Mississippi, 56%; Montana, 67%; Nevada, 55%; and West Virginia, 53%) in 1989.

Free access
in Journal of the American Veterinary Medical Association

Abstract

OBJECTIVE To evaluate in vitro phagocytosis and bactericidal activity of circulating blood neutrophils in horses with severe equine asthma and control horses and to determine whether circulating blood neutrophils in horses with severe equine asthma have an increase in expression of the proinflammatory cytokine tumor necrosis factor (TNF)-α and the chemokine interleukin (IL)-8 and a decrease in expression of the anti-inflammatory cytokine IL-10 in response to bacteria.

ANIMALS 6 horses with severe equine asthma and 6 control horses.

PROCEDURES Circulating blood neutrophils were isolated from horses with severe equine asthma and control horses. Phagocytosis was evaluated by use of flow cytometry. Bactericidal activity of circulating blood neutrophils was assessed by use of Streptococcus equi and Streptococcus zooepidemicus as targets, whereas the cytokine mRNA response was assessed by use of a quantitative PCR assay.

RESULTS Circulating blood neutrophils from horses with severe equine asthma had significantly lower bactericidal activity toward S zooepidemicus but not toward S equi, compared with results for control horses. Phagocytosis and mRNA expression of TNF-α, IL-8, and IL-10 were not different between groups.

CONCLUSIONS AND CLINCAL RELEVANCE Impairment of bactericidal activity of circulating blood neutrophils in horses with severe equine asthma could contribute to an increased susceptibility to infections.

Full access
in American Journal of Veterinary Research

Abstract

Objective—To evaluate whether the leukotriene (LT) D4 receptor antagonist L-708,738 is therapeutically beneficial in treating horses with recurrent airway obstruction (heaves).

Animals—12 adult horses with heaves and healthy lung lobes from 20 slaughtered horses.

Procedure—Lung lobes were used for smooth muscle tension and radioligand binding studies. Horses with heaves were given a placebo for 14 days and administered L-708,738 (n = 6; 2.5 mg/kg PO, q 12 h) or dexamethasone (6; 0.04 mg/kg, IV, q 24 h) from days 14 to 28. Pulmonary function was measured weekly for 36 days, and bronchoalveolar cells were collected on days 0, 14, and 29 for cytologic examination.

Results—Nanomolar concentrations of L-708,738 were effective at antagonizing LTD4-induced bronchoconstriction and LTD4-receptor binding in lung lobes. Mean peak and trough L-708,738 plasma concentrations during the treatment period were 1.54 and 0.28 μM, respectively. On days 21 and 29, lung mechanics were significantly improved in the dexamethasone- treated horses but not in the L-708,738-treated horses. Neither dexamethasone nor L-708,738 had a significant effect on cytologic findings.

Conclusions and Clinical Relevance—L-708,738 was bioavailable after oral administration and sustained concentrations in plasma during the dosing period that exceeded in vitro efficacy values. However, airway function did not improve, suggesting that either drug concentrations in the lungs were subtherapeutic or that cysteinyl LT may not be important mediators of airway inflammation in heaves. Results provide the first evidence of cysteinyl LT1 receptors in airways of horses. (Am J Vet Res 2002;63:579–585)

Full access
in American Journal of Veterinary Research

Abstract

Objective—To measure the relationship between gross lesions in swine carcasses observed at a processing plant and Salmonella contamination and to determine whether nonexpert assessments of lesion status would correspond with swine pathologists' judgments.

Animals—Carcasses of 202 conventionally raised and 156 antimicrobial-free pigs in a Midwestern US processing plant examined from December 2005 to January 2006.

Procedures—4 replicates were conducted. For each, freshly eviscerated carcasses were identified as having or lacking visceral adhesions by a nonexpert evaluator and digital carcass photographs were obtained. Swab specimens were obtained from carcasses before the final rinse stage of processing, and bacterial culture for Salmonella spp and Enterococcus spp was performed. Subsequently, carcass photographs were numerically scored for lesion severity by 3 veterinary pathologists. Results were used to test the ability of lesion detection to predict bacterial contamination of carcasses and the agreement between judgments of the inexperienced and experienced assessors.

Results—The probability of Salmonella contamination in carcasses with lesions identified at the abattoir was 90% higher than that in carcasses lacking lesions, after controlling for replicate identity and antimicrobial use. The receiver operating characteristic curve and Cohen κ indicated close agreement between lesion detection at the abattoir and by the 3 pathologists.

Conclusions and Clinical Relevance—Findings indicated the presence of lesions could be used to predict Salmonella contamination of swine carcasses and that a nonexpert processing-line assessment of lesions could be used to discriminate between healthy and chronically ill swine before their entry into the human food supply.

Full access
in American Journal of Veterinary Research

Abstract

CASE DESCRIPTION

A 3-year-old 5-kg sexually intact female silvery langur housed in a single-species group at a zoological institution was presented because of acute trauma to the left forelimb.

CLINICAL FINDINGS

Radiography of the left forelimb revealed a type II Monteggia fracture (proximal ulnar fracture with cranial displacement and caudal luxation of the radial head). During surgery, disruption of the annular ligament and rupture of the lateral collateral ligament were noted.

TREATMENT AND OUTCOME

The langur underwent open reduction and internal fixation of the ulnar fracture and placement of a radioulnar positional screw, a prosthetic lateral collateral ligament, and a temporary hinged type 1A external skeletal fixator. The langur was returned to group housing, underwent behavioral training, and was periodically anesthetized for physical therapy sessions to improve range of motion of the left elbow joint. The external skeletal fixator was removed 4 weeks after surgery, and the radioulnar positional screw was removed 6 weeks after surgery. Three months after surgery, the range of motion of the langur’s left elbow joint was considered normal, and the animal returned to normal activity.

CLINICAL RELEVANCE

For the captive silvery langur of the present report, surgical stabilization and postoperative management of a type II Monteggia fracture of the left forelimb were successful with recovery of elbow joint function. These techniques may be applied to other captive nonhuman primates, including those that brachiate or are members of social species that must be housed with conspecifics in the postoperative period to maintain group dynamics.

Full access
in Journal of the American Veterinary Medical Association

Abstract

Objective

To characterize the cardiovascular response to IV administration of serotonin (5-hydroxytryptamme [5- HT]) in calves.

Animals

5 healthy unsedated Friesian calves.

Procedure

41 5-HT administrations were performed: 11 slow infusions (duration, 5 minutes) and 30 bolus infusions (duration, 5 seconds). Cardiovascular function values were recorded before, during, and after the infusions.

Results

Slow infusion of 5-HT first resulted in a brief period of severe bradycardia, then in sustained tachycardia with a concomitant increase in cardiac output. Systemic blood pressure response to 5-HT was triphasic, with initial hypotension concomitant with bradycardia, then a pressor phase associated with an increase in systemic vascular resistance, and finally, a long-lasting hypotensive phase associated with decreased systemic vascular resistance. Pulmonary hypertension was associated with increased pulmonary vascular resistance, reflecting intense pulmonary vasoconstriction. Bolus infusion at increasing dosages resulted in dose-dependent bradycardia and systemic hypotension, followed by dose-dependent systemic hypertension. Unlike with slow infusion, neither the second tachycardic nor the third systemic hypotensive phases were evident.

Conclusions

5-HT induces dose-dependent cardiovascular responses, including a reflex response followed by pulmonary and systemic vasoconstriction, in healthy calves.

Clinical Relevance

Determining the type of serotonergic receptors responsible for these responses may help to determine whether 5-HT is involved in the mechanisms underlying brisket disease in cattle. (Am J Vet Res 1996; 57:731–738)

Free access
in American Journal of Veterinary Research

Abstract

Objective

To evaluate left and right ventricular filling and ejection performances by use of Doppler echocardiography in healthy, conscious dogs submitted to dobutamine stress testing.

Animals

10 unsedated, healthy adult Beagles.

Procedure

Doppler echocardiography was performed during cardiac stress testing on each dog twice at 24-hour intervals. Dobutamine was infused in 10 µg/kg of body weight/min incremental dosages, from 12.5 to 42.5 µg/kg/min. Duration of each step was 15 minutes. Doppler measurements were recorded at baseline and at each stage of dobutamine infusion, whereas aortic diameter was measured at baseline and at peak dosage by use of two-dimensional echocardiography.

Results

Dobutamine infusion induced a significant increase in velocity time integrals and in peak flow velocities at the aortic, pulmonic, mitral, and tricuspid valves. Acceleration time-to-deceleration time ratio at the aortic wave also was increased significantly. On the other hand, ejection time, acceleration time, and deceleration time at the aortic and pulmonic valves and peak flow velocity of the E wave-to-peak flow velocity of the A wave ratio at the mitral and tricuspid valves decreased significantly during the test. The acceleration time-to-deceleration time ratio at the pulmonic wave was unchanged. A significant, progressive increase in cardiac index also was observed during dobutamine infusion, with a maximal increase of 104% from baseline. This was mediated initially by an increase in stroke index and, at higher dosages, by an increase in heart rate.

Conclusions and Clinical Relevance

Doppler echocardiography performed during dobutamine stress testing may be a reliable method of assessing myocardial function in dogs with cardiovascular disease. (Am J Vet Res 1999;60:865–871)

Free access
in American Journal of Veterinary Research