Objective-To evaluate the use of CT and MRI for guidance of osteochondral sample collection for histologic detection of early osteoarthritic lesions in centrodistal (distal intertarsal) joints of horses. Sample -Right tarsal joints from the cadavers of 24 Icelandic horses aged 29 to 31 months. Procedures-CT and MRI were used to evaluate the extent of suspected osteoarthritic changes in centrodistal joints, which were graded with a semiquantitative system. The anatomic regions with the highest grade of change were identified, and osteochondral samples were obtained from these regions. Samples were also obtained from the same centrodistal joints at predetermined sites. Histologic examination of all samples was performed, with samples classified as negative or positive for osteoarthritis, and results were compared between sample collection methods. Results-Histologic examination revealed osteoarthritic lesions in 29% (7/24) of centrodistal joints with the predetermined method and in 63% (15/24) with the image-guided method. Significant associations were identified between histologic osteoarthritis detection and the summed image-guided sample collection site image grades, central osteophytes, articular cartilage thickness abnormalities, grade 2 articular mineralization front defects, and grade 2 marginal osteophytes. Conclusions and Clinical Relevance-CT and MRI aided the detection of focal changes suggestive of early-stage osteoarthritis in the centrodistal joints of equine cadavers and may be useful for detection of similar disease in live horses. The first morphological changes of centrodistal joint osteoarthritis were suspected to be in the articular cartilage and the articular mineralization front regions.

Objective-To quantify peripheral blood neutrophil apoptosis in equine patients with acute abdominal disease (ie, colic) caused by strangulating or nonstrangulating intestinal lesions and compare these values with values for horses undergoing elective arthroscopic surgery. Animals-20 client-owned adult horses. Procedures-Peripheral blood was collected from horses immediately prior to and 24 hours after surgery for treatment of colic (n = 10) or elective arthroscopic surgery (10), and neutrophils were counted. Following isolation by means of a bilayer colloidal silica particle gradient and culture for 24 hours, the proportion of neutrophils in apoptosis was detected by flow cytometric evaluation of cells stained with annexin V and 7-aminoactinomycin D. Values were compared between the colic and arthroscopy groups; among horses with colic, values were further compared between horses with and without strangulating intestinal lesions. Results-Percentage recovery of neutrophils was significantly smaller in preoperative samples (median, 32.5%) and in all samples combined (35.5%) for the colic group, compared with the arthroscopy group (median, 66.5% and 58.0%, respectively). No significant differences in the percentages of apoptotic neutrophils were detected between these groups. Among horses with colic, those with strangulating intestinal lesions had a significantly lower proportion of circulating apoptotic neutrophils in postoperative samples (median, 18.0%) than did those with nonstrangulating lesions (66.3%). Conclusions and Clinical Relevance-The smaller proportion of apoptotic neutrophils in horses with intestinal strangulation suggested that the inflammatory response could be greater or prolonged, compared with that of horses with nonstrangulating intestinal lesions. Further investigations are needed to better understand the relationship between neutrophil apoptosis and inflammation during intestinal injury.

Objective: To develop a broad-range 28S ribosomal DNA quantitative PCR (qPCR) assay for detection of fungal DNA in equine endometrial samples. Sample: 12 fungal samples from a clinical diagnostic laboratory and 29 samples obtained from 17 mares. Procedures: The qPCR assay was optimized with commercially acquired fungal organisms and validated with samples obtained from the clinical diagnostic laboratory. Subsequently, 29 samples from 17 mares suspected of having fungal endometritis were evaluated via the qPCR assay and via traditional fungal culture and endometrial cytology. Amplicons from the qPCR assay were subjected to genetic sequencing to identify the organisms. Results: The qPCR assay theoretically had a detection threshold of 2 organisms of Candida albicans. Fungal DNA was amplified from all 12 fungal samples from the commercial diagnostic laboratory. Fungal identification by use of genetic sequencing was successful for 34 of 36 amplicons from the 12 samples assayed. A fungal agent was identified via qPCR assay and genetic sequencing in all 12 samples; in contrast, a fungal agent was identified in only 8 of 12 samples via standard fungal culture and biochemical analysis. The qPCR assay detected fungal DNA in samples from 12 of 17 mares suspected of having fungal endometritis. Conclusions and Clinical Relevance: A rapid, sensitive, and repeatable qPCR assay was developed for detection of fungal DNA from equine endometrial samples. The qPCR may prove to be clinically useful as an adjunct to microbial culture and cytologic examination to provide identification of fungal organisms in a timely manner.

Objective: To evaluate protein expression in bronchoalveolar lavage fluid (BALF) obtained from West Highland White Terriers with idiopathic pulmonary fibrosis (IPF), dogs with chronic bronchitis, and healthy control dogs to identify potential biomarkers for IPF. Samples: BALF samples obtained from 6 West Highland White Terriers with histologically confirmed IPF, 5 dogs with chronic bronchitis, and 4 healthy Beagles. Procedures: Equal amounts of proteins in concentrated BALF samples were separated via 2-D differential gel electrophoresis. Proteins that were differentially expressed relative to results for healthy control dogs were identified with mass spectrometry and further verified via western blotting. Results: Expression of 6 proteins was upregulated and that of 1 protein was downregulated in dogs with IPF or chronic bronchitis, compared with results for healthy dogs. Expression of proteins β-actin, complement C3, α-1-antitrypsin, apolipoprotein A-1, haptoglobin, and transketolase was upregulated, whereas expression of lysozyme C was downregulated. Conclusions and Clinical Relevance: Proteomics can be used to search for biomarkers and to reveal disease-specific mechanisms. The quantitative comparison of proteomes for BALF obtained from dogs with IPF and chronic bronchitis and healthy dogs revealed similar changes for the dogs with IPF and chronic bronchitis, which suggested a common response to disease processes in otherwise different lung diseases. Specific biomarkers for IPF were not identified.

Objective-To compare β-hydroxybutyrate (BHB) and glucose concentrations measured with a dual-purpose point-of-care (POC) meter designed for use in humans and a laboratory biochemical analyzer (LBA) to determine whether the POC meter would be reliable for on-farm measurement of blood glucose and BHB concentrations in sheep in various environmental conditions and nutritional states. Animals-36 pregnant mixed-breed ewes involved in a maternal feed restriction study. Procedures-Blood samples were collected from each sheep at multiple points throughout gestation and lactation to allow for tracking of gradually increasing metabolic hardship. Whole blood glucose and BHB concentrations were measured with the POC meter and compared with serum results obtained with an LBA. Results-464 samples were collected. Whole blood BHB concentrations measured with the POC meter compared well with LBA results, and error grid analysis showed the POC values were acceptable. Whole blood glucose concentrations measured with the POC meter had more variation, compared with LBA values, over the glucose ranges evaluated. Results of error grid analysis of POC-measured glucose concentrations were not acceptable, indicating errors likely to result in needless treatment with glucose or other supplemental energy sources in normoglycemic sheep. Conclusions and Clinical Relevance-The POC meter was user-friendly and performed well across a wide range of conditions. The meter was adequate for detection of pregnancy toxemia in sheep via whole blood BHB concentration. Results should be interpreted with caution when the POC meter is used to measure blood glucose concentrations.

Objective-To investigate whether differences existed between clinically normal dogs and dogs with goniodysgenesis-related glaucoma (GDRG) in serum autoantibodies against optic nerve antigens. Animals-16 dogs with GDRG, 17 healthy dogs with unremarkable pectinate ligament and iridocorneal angle morphology, and 13 euthanized dogs with no major ocular abnormalities or underlying diseases. Procedures-Western blotting was performed with optic nerve extracts from the euthanized dogs as an antigen source and serum from clinically normal dogs and dogs with GDRG as a primary antibody (autoantibody) source. Blots were evaluated for presence and density of bands. Results-Multiple bands were identified on western blots from all dogs with GDRG and all clinically normal dogs, with a high degree of variability among individual dogs. Dogs with GDRG were significantly more likely than healthy dogs to have bands present at 38, 40, and 68 kDa. Dogs with GDRG had significant increases in autoreactivity at 40 and 53 kDa and a significant decrease in autoreactivity at 48 kDa. Conclusions and Clinical Relevance-Significant differences in serum autoantibodies against optic nerve antigens were found in dogs with versus without GDRG. Although it remains unclear whether these differences were part of the pathogenesis of disease or were sequelae to glaucomatous changes, these findings provide support for the hypothesis that immune-mediated mechanisms play a role in the development or progression of GDRG. However, the high degree of variability among individual dogs and the considerable overlap between groups suggest that the clinical usefulness of this technique for distinguishing dogs with GDRG from clinically normal dogs is likely limited.

Objective-To quantify left ventricle (LV) volumes by use of 1-D, 2-D, and 3-D echocardiography versus MRI in dogs. Animals-10 healthy Beagles. Procedures-During anesthesia, each dog underwent an echocardiographic examination via the Teichholz method, performed on the basis of standard M-mode frames (1-D); the monoplane Simpson method of disk (via 2-D loops); real-time triplane echocardiography (RTTPE) with a 3-D probe; and real-time 3-D echocardiography with a 3-D probe. Afterward, cardiac MRI was performed. Values for the LV end-diastolic volume (EDV), end-systolic volume (ESV), and ejection fraction (EF) were compared between each echocardiographic method and the reference method (cardiac MRI). Results-No significant differences for EDV, ESV, and EF were detected between RTTPE and cardiac MRI. Excellent correlations (r = 0.97, 0.98, and 0.95 for EDV, ESV, and EF, respectively) were found between RTTPE and values for cardiac MRI. The other echocardiographic methods yielded values significantly different from cardiac MRI and results correlated less well with results of cardiac MRI for EDV, ESV, and EF. Use of the Teichholz method resulted in LV volume overestimation, whereas the Simpson method of disk and real-time 3-D echocardiography significantly underestimated LV volumes. Conclusions and Clinical Relevance-Use of RTTPE yielded excellent correlations and nonsignificant differences with cardiac MRI and is a suitable method for routine veterinary cardiac examination.

Objective-To qualitatively describe lung CT images obtained from sedated healthy equine neonates (≤ 14 days of age), use quantitative analysis of CT images to characterize attenuation and distribution of gas and tissue volumes within the lungs, and identify differences between lung characteristics of foals ≤ 7 days of age and foals > 7 days of age. Animals-10 Standardbred foals between 2.5 and 13 days of age. Procedures-Foals were sedated with butorphanol, midazolam, and propofol and positioned in sternal recumbency for thoracic CT. Image analysis software was used to exclude lung from nonlung structures. Lung attenuation was measured in Hounsfield units (HU) for analysis of whole lung and regional changes in attenuation and lung gas and tissue components. Degree of lung attenuation was classified as follows: hyperinflated or emphysema, −1,000 to −901 HU; well aerated, −900 to −501 HU; poorly aerated, −500 to −101 HU; and nonaerated, > −100 HU. Results-Qualitative evidence of an increase in lung attenuation and patchy alveolar patterns in the ventral lung region were more pronounced in foals ≤ 7 days of age than in older foals. Quantitative analysis revealed that mean +/- SD lung attenuation was greater in foals ≤ 7 days of age (−442 +/- 28 HU) than in foals > 7 days of age (−521 +/- 24 HU). Lung aeration and gas volumes were lower than in other regions ventrally and in the mid lung region caudal to the heart. Conclusions and Clinical Relevance-Identified radiographic patterns and changes in attenuation were most consistent with atelectasis and appeared more severe in foals ≤ 7 days of age than in older neonatal foals. Recognition of these changes may have implications for accurate CT interpretation in sedated neonatal foals with pulmonary disease.

Objective—To determine the pharmacokinetics and hemodynamic effects of trazodone after IV and oral administration in dogs and bioavailability after oral administration. Animals—6 adult Beagles. Procedures—Dogs received trazodone HCl (8 mg/kg) orally and IV in a randomized controlled crossover design. Blood samples were collected at various times after administration. Heart rates and indirectly measured blood pressures of dogs and plasma concentrations and pharmacokinetics of trazodone were determined. Results—Following IV administration, the mean ± SD elimination half-life, apparent volume of distribution, and plasma total body clearance were 169 ± 53 minutes, 2.53 ± 0.47 L/kg, and 11.15 ± 3.56 mL/min/kg, respectively. Following oral administration, the mean ± SD elimination half-life and absolute bioavailability were 166 ± 47 minutes and 84.6 ± 13.2%, respectively. Maximum plasma concentration following oral administration was 1.3 ± 0.5 μ/mL, and time to maximum plasma concentration was 445 ± 271 minutes. After IV administration, all dogs immediately developed transient tachycardia (184.3 ± 8.0 beats/min), and 3 of 6 dogs developed aggression. Increase in heart rate was significantly associated with increase in plasma drug concentration following IV administration. Conclusions and Clinical Relevance—Results of this study indicated oral administration of trazodone resulted in acceptable absolute bioavailability, with substantial variability in time to maximum plasma concentration. Individualized approaches in dosing intervals may be necessary for dogs receiving oral trazodone. An orally administered dose of 8 mg/kg was well tolerated in dogs; IV administration of a dose of 8 mg/kg caused substantial adverse effects, including tachycardia and behavior disinhibition.

Objective: To evaluate the effects of 4.7-mg deslorelin acetate implants on egg production and plasma concentrations of 17β-estradiol and androstenedione in Japanese quail (Coturnix coturnix japonica) over 180 days and assess safety of the implants in quail via gross and histologic examination. Animals: 20 female Japanese quail. Procedures: Following a 7-day period of consistent egg laying, quail were anesthetized and received a 4.7-mg deslorelin implant (treatment group; n = 10) or identical placebo implant (control group; 10) SC between the scapulae. Egg production was monitored daily. Plasma concentrations of 17β-estradiol and androstenedione were measured on days 0 (immediately prior to implant injection), 14, 29, 62, 90, 120, 150, and 180 via radioimmunoassay. Birds were weighed periodically and euthanized at day 180 for complete necropsy. Results: Egg production was significantly decreased in the treatment group, compared with the control group, from 2 to 12 weeks after implant injection. Egg production ceased in 6 of 10 quail in the treatment group (mean duration of cessation, 70 days). Plasma androstenedione and 17β-estradiol concentrations were significantly lower on day 29 in the treatment group than in the control group. Plama androstenedione and 17β-estradiol concentrations were significantly lower on day 29 in the treatment group then in the control group. Conclusions and Clinical Relevance: 4.7-mg deslorelin acetate implants reversibly decreased egg laying for approximately 70 days in most of the Japanese quail evaluated. Further studies evaluating implants containing different concentrations of the drug are needed in quail and other avian species.