Temporal and subcellular distributions of hyaluronic acid (HA) as a degradable nanoparticle (NP) in animals were investigated to determine if HA-NP could be utilized as an appropriate drug delivery system. After mice were intravenously injected with 5 mg/kg of Cy5.5-labeled HA-NP sized 350-400 nm or larger HA-polymers, the fluorescence intensity was measured in all homogenized organs from 0.5 h to 28 days. HA-NP was greatly detected in spleen, liver and kidney until day 28, while it was maintained at low levels in other organs. HA-polymer was observed at low levels in all organs. HA-NP quantities in spleen and liver were reduced until day 3, but increased sharply between days 3 and 7, then decreased again, while their HA-polymers were maintained at low levels until day 28. In kidneys, both HA-NP and HA-polymer showed high levels after 0.5 h of administration, but steadily decreased until day 28. According to ultrastructural analyses, HA-NP was engulfed in Kupffer cells of liver and macrophages of spleen and kidney at day 1 and was accumulated in the cytoplasm of kidney tubular cells at day 7. Overall, these findings suggest that HA-NP could be considered a desirable drug carrier in the liver, kidney, or spleen.

This study was undertaken to develop new analytical methods for assessment of anticoccidials. Highperformance liquid chromatography (HPLC) was found to be a fast, reliable, and practical method. The anticoccidials used in this experiment were toltrazuril and diclazuril, and the analysis factors were specificity, linearity, accuracy, repeatability, and intermediate precision. The linearity of each anticoccidial was better than 0.99, and the accuracies were 99.5% and 99.1% with relative SD of 0.5 and 0.4, respectively. To assess whether the developed HPLC method could be effectively applied, toltrazuril and diclazuril post-market veterinary products (five products) that are currently sold were tested. The results revealed no non-compliant items and the method was applied successfully. Therefore, the newly developed HPLC method for anticoccidial assessment described in this study may be useful as a reference method in the Korean Standards of Veterinary Pharmaceuticals for the analysis of toltrazuril and diclazuril.

To reduce swine production costs, a slaughter check system has been developed in countries with an advanced swine industry. Evaluation of lung lesions in carcasses is a critical part of the slaughter check system. This study was performed to collect background information for use in developing a slaughter check system in Korea. Lung tissues and their gross images were collected from slaughterhouses in Gyeonggi-do, Korea. Scoring of the gross lung lesions was performed on the lung images. Histopathologic examination was conducted to classify the pulmonary lesions as bronchopneumonia or interstitial pneumonia. Scores of the gross lung lesions were significantly different between bronchopneumonia and interstitial pneumonia groups (p less than 0.001). A 90% confidence interval of gross lung lesion scores was established for the bronchopneumonia group, and the lesion scoring had a sensitivity of 100% and specificity of 77.3%. The gross lung lesion scoring test was subjected to a diagnostic distinction evaluation by examining the receiver operating characteristic curve and was appraised as having good discrimination for bronchopneumonia. Establishment of a gross lung lesion scoring test for the diagnosis of bronchopneumonia could be valuable as a screening test of macroscopic bronchopneumonia in swine slaughter check system.

A 2-year-old, female Pomeranian dog was referred for dyspnea. Thoracic radiographs revealed left-sided mediastinal shift, increased soft tissue opacity in the caudal aspect of left thorax with loss of the left diaphragmatic silhouette, and dorsal elevation of mediastinal structures and heart from the sternum by lung tissue. The left main bronchus was visualized as an air-bronchogram and observed to abruptly discontinue at the level of the 10th rib. Thoracic computed tomography (CT) revealed absence of the left lung parenchyma and left pulmonary vessels with a rudimentary left main bronchus. The case was congenital pulmonary aplasia diagnosed via radiography and CT.

Two Whooper swan (Cygnus cygnus) died after suffering from pododermatitis, lethargy, and ataxia; necropsy was performed. Grossly, the liver was swollen and firm. The kidney and spleen were also enlarged and a pale tan color. On histopathologic examination with Congo red staining, amyloidosis was noted in liver, spleen, and kidney. In addition, marked osseous metaplasia was present in the liver. Based on these results, systemic amyloidosis involving liver, spleen, and kidney with osseous metaplasia in the liver was diagnosed. Study results indicate that an inflammatory reaction associated with pododermatitis had a role in the amyloidosis in this particular case.

A recombinase polymerase amplification (RPA)-based method was developed for rapid and specific detection of African swine fever virus (ASFV), the etiologic agent of African swine fever, a devastating disease of swine. Primers and the exo probe targeting the conserved region of the P72 gene of ASFV were designed and the reaction was run on the Genie III scanner device. Using recombinant plasmid DNA containing the P72 gene as template, we showed that the amplified product could be detected in less than 10 min and that the detection limit was 102 copies DNA/reaction [same detection limit as real-time polymerase chain reaction (PCR)]. The RPA assay did not cross-detect CSFV, PCV-2, PRV, PRRSV, or FMDV, common viruses seen in pigs. Tests of recombinant plasmid-spiked serum samples revealed that RPA and real-time PCR had the same diagnostic rate. The RPA assay, which is simple, cost-effective, and fast, is a promising alternative to real-time PCR for ASFV detection.

The digital cushion (DC) plays a role in absorbing and dampening forces applied to the foot and therefore supports internal structures such as navicular bone; yet, its architecture is not well-known. The goal of this study was to characterize the microanatomical structure of the DC in horses with clinically sound hooves. Both forefeet from the cadavers of 12 adult Quarter horses were cut and sectioned and samples of the following 4 regions of the DC were obtained: axial proximal (AxProx), axial distal (AxDis), abaxial lateral (AbxLat), and abaxial medial (AbxMed). The samples were processed and stained with hematoxylin and eosin, Masson's trichrome, and Weigert's elastic stains. On each slide, 2 central 3- × 3-mm areas were microscopically assessed and all measurements were done within the 9-mm2 area. The number of detected collagen bundles, nerve fascicles, vessels, and the diameter of wall thickness and lumen of blood vessels were measured. Elastic fiber profiles were categorized based on relative density of elastic fibers detected in the field. The percentage of samples in which chondrocytes and adipose tissues were either present or absent was calculated. Significant structural differences were identified among the 4 regions of the DC. The AxDis region contained more collagen bundles (P < 0.0001) and less elastic fiber profiles than the AxProx region (P < 0.0001). The AxDis also contained more collagen bundles than the AbxMed and AbxLat (P < 0.0001) regions. Our findings provide insight into the structure of the DC of mature Quarter horses. The structural differences in the various regions of the DC are presumably related to the different functional properties of those regions; yet more research is warranted.

Muscle loss associated with disease (cachexia) or with aging (sarcopenia) is common in dogs, but clinically relevant methods for quantifying muscle loss are needed. We previously validated an ultrasound method of quantifying muscle size in dogs in a single breed. The goal of this study was to assess the variability and reproducibility of the Vertebral Epaxial Muscle Score (VEMS) in other dog breeds. Static ultrasound images were obtained from 38 healthy, neutered dogs of 5 different breeds between 1- and 5-years-old. The maximal transverse right epaxial muscle height and area at the level of the 13th thoracic vertebra (T13) were measured. Length of the 4th thoracic vertebra (T4) was measured from thoracic radiography. Ratios of the muscle height and area to vertebral length (height/T4 and area/T4, respectively) were calculated to account for differences in body size among breeds. Reproducibility testing was performed on 2 dogs of each breed (26% of the total) to determine intra- and inter-investigator reproducibility, as well as intra-class correlation. Mean height/T4 = 1.02 ± 0.18 and mean area/T4 = 3.32 ± 1.68. There was no significant difference for height/T4 (P = 0.10) among breeds, but breeds were significantly different in area/T4 (P < 0.001). Intra-class correlation ranged from 0.80 to 0.99. Testing showed better reproducibility for height/T4 compared to area/T4. The VEMS using height/T4 was valid and reproducible for healthy dogs of different sizes and body conformations. Studies assessing this technique in dogs with congestive heart failure and other diseases associated with muscle loss are warranted.

OBJECTIVE To evaluate expression of procoagulant tissue factor (TF) by canine hemangiosarcoma cells in vitro. SAMPLES 4 canine hemangiosarcoma cell lines (SB-HSA [mouse-passaged cutaneous tumor], Emma [primary metastatic brain tumor], and Frog and Dal-1 [primary splenic tumors]) and 1 nonneoplastic canine endothelial cell line (CnAoEC). PROCEDURES TF mRNA and TF antigen expression were evaluated by quantitative real-time PCR assay and flow cytometry, respectively. Thrombin generation was measured in canine plasma and in coagulation factor–replete or specific coagulation factor–deficient human plasma by calibrated automated thrombography. Corn trypsin inhibitor and annexin V were used to examine contributions of contact activation and membrane-bound phosphatidylserine, respectively, to thrombin generation. RESULTS All cell lines expressed TF mRNA and antigen, with significantly greater expression of both products in SB-HSA and Emma cells than in CnAoEC. A greater percentage of SB-HSA cells expressed TF antigen, compared with other hemangiosarcoma cell lines. All hemangiosarcoma cell lines generated significantly more thrombin than did CnAoEC in canine or factor-replete human plasma. Thrombin generation induced by SB-HSA cells was significantly lower in factor VII–deficient plasma than in factor-replete plasma and was abolished in factor X–deficient plasma; residual thrombin generation in factor VII–deficient plasma was abolished by incubation of cells with annexin V. Thrombin generation by SB-HSA cells was unaffected by the addition of corn trypsin inhibitor. CONCLUSIONS AND CLINICAL RELEVANCE Hemangiosarcoma cell lines expressed procoagulant TF in vitro. Further research is needed to determine whether TF can be used as a biomarker for hemostatic dysfunction in dogs with hemangiosarcoma.

The objective of this study was to evaluate the ability of a long-term antioxidant-supplemented diet to regulate the oxidative stress and general health status of dogs involved in animal-assisted intervention (AAI) programs. Oxidative stress is a consequence of the accumulation of reactive oxygen species (ROS). Exercise-induced oxidative stress can increase muscle fatigue and fiber damage and eventually leads to impairment of the immune system. A randomized, placebo-controlled, crossover clinical evaluation was conducted with 11 healthy therapy dogs: 6 females and 5 males of different breeds and with a mean age of 2.7 ± 0.8 y (mean ± SEM). The dogs were divided into 2 groups, 1 fed a high quality commercial diet without antioxidants (CD) and the other a high quality commercial diet supplemented with antioxidants (SD) for 18 wk. After the first 18 wk, metabolic parameters, reactive oxygen metabolite-derivatives (d-ROMs), and biological antioxidant potential (BAP) levels were monitored and showed a significant reduction of d-ROMs, triglycerides, and creatinine values in the SD group (P < 0.05) and a significant increase in amylase values in the CD group (P < 0.01). At the end of this period, groups were crossed over and fed for another 18 wk. A significant decrease in amylase and glutamate pyruvate transaminase (GPT) values was observed in the CD and SD group, respectively (P < 0.05). In conclusion, a controlled, balanced antioxidant diet may be a valid approach to restoring good cell metabolism and neutralizing excess free radicals in therapy dogs.