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.
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.
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.
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.
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.
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.
Objective—To evaluate whether the leukotriene (LT)
D4 receptor antagonist L-708,738 is therapeutically
beneficial in treating horses with recurrent airway
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)
OBJECTIVE To describe use of whole-genome sequencing (WGS) and evaluate the apparent sensitivity and specificity of antemortem tuberculosis tests during investigation of an unusual outbreak of Mycobacterium bovis infection in a Michigan dairy herd.
PROCEDURES All cattle in the index dairy herd were screened for bTB with the caudal fold test (CFT), and cattle ≥ 6 months old were also screened with a γ-interferon (γIFN) assay. The index herd was depopulated along with all barn cats and a dog that were fed unpasteurized milk from the herd. Select isolates from M bovis–infected animals from the index herd and other bTB-affected herds underwent WGS. Wildlife around all affected premises was examined for bTB.
RESULTS No evidence of bTB was found in any wildlife examined. Within the index herd, 53 of 451 (11.8%) cattle and 12 of 21 (57%) cats were confirmed to be infected with M bovis. Prevalence of M bovis–infected cattle was greatest among 4- to 7-month-old calves (16/49 [33%]) followed by adult cows (36/203 [18%]). The apparent sensitivity and specificity were 86.8% and 92.7% for the CFT and 80.4% and 96.5% for the γIFN assay when results for those tests were interpreted separately and 96.1% and 91.7% when results were interpreted in parallel. Results of WGS revealed that M bovis–infected barn cats and cattle from the index herd and 6 beef operations were infected with the same strain of M bovis. Of the 6 bTB-affected beef operations identified during the investigation, 3 were linked to the index herd only by WGS results; there was no record of movement of livestock or waste milk from the index herd to those operations.
CONCLUSIONS AND CLINICAL RELEVANCE Whole-genome sequencing enhanced the epidemiological investigation and should be used in all disease investigations. Performing the CFT and γIFN assay in parallel improved the antemortem ability to detect M bovis–infected animals. Contact with M bovis–infected cattle and contaminated milk were major risk factors for transmission of bTB within and between herds of this outbreak.