Porcine ear necrosis syndrome is characterized by erosive and ulcerative lesions at the margin or tip of the pinna. Three growing pigs of different ages exhibited retarded growth accompanied by reddening and necrosis of ear prior to death. Gross examination showed reddening, swelling, black discoloration, scaling, and variable-sized yellowish materials and edema in ear cross section. Microscopically, thrombosis, abscess, ulceration, epidermal hyperplasia, and dermal pyogranulomatous inflammation with an intralesional bacterial colony were observed. Staphylococcus hyicus was isolated in all pigs' ears and porcine reproductive and respiratory syndrome virus was detected by PCR and immunohistochemistry.

This study was performed to investigate the distribution of ticks and the rate of infection with severe fever with thrombocytopenia syndrome (SFTS) virus in ticks collected at Mt. Gwanak and the Seoul National University campus, Korea. Ticks (n = 273) were collected from May to October and included 76 Haemaphysalis longicornis (4 adult females, 72 nymphs), 49 Haemaphysalis flava (9 adult females, 3 adult males, 37 nymphs), and 148 Haemaphysalis spp. larvae. SFTS virus detection was performed by using one-step RT PCR and nested PCR. The SFTS virus was detected in 7 samples (1 Haemaphysalis longicornis nymph, 3 Haemaphysalis flava nymphs, and 3 Haemaphysalis spp. larva). The overall minimum field infection rate was 2.6%, whereas the minimum field infection rates of adult, nymphal, and larval ticks were 0%, 3.2%, and 2.0%, respectively. For a more accurate indication of the prevalence of SFTS virus in Korea, further in-depth investigations of tick species and SFTS virus occurrence over a larger area and longer period are needed.

Porcine parvovirus, Erysipelothrix (E.) rhusiopathiae, and Leptospira (L.) interrogans are considered major etiologic agents of reproductive failure in pigs, causing economic loss in the swine industry. In this study, the safety and immunogenicity of a new octavalent inactivated vaccine were evaluated. The vaccine contained inactivated porcine parvovirus, E. rhusiopathiae, and six L. interrogans serovars (Bratislava, Canicola, Grippotyphosa, Hardjo, Icterohaemorrhagiae, and Pomona). Safety test results showed no notable side effects or clinical signs after vaccination in mice, guinea pigs, and sows. In addition, we assessed immunogenicity of the vaccine in 25 sows under field conditions. The vaccinated group (n = 20) had a significantly higher antibody level than the non-vaccinated group (n = 5). Moreover, the stillbirth rate decreased in piglets born from vaccinated sows, resulting in an increased fertility rate. The results of this study demonstrate that the new octavalent inactivated vaccine can be applied safely and effectively to improve reproductive performance in sows.

Antihypertensive effects of ethanol extracts of Aralia elata (Miq.) Seem. (AE) were investigated in spontaneously hypertensive rats (SHR). SHR aged 14 weeks were treated for 8 weeks with AE (10 or 50 mg/kg/day) or amlodipine besylate (Am; 10 mg/kg/day) orally. Hypertension results in injury to several organs and can produce a significant increase in malondialdehyde (MDA) content as a result of lipid peroxidation and endothelial dysfunction. In this study, oral administration of AE and Am significantly reduced systolic blood pressure, organ weight index, and MDA content in tissues but increased significantly the plasma nitrite and nitrate concentrations. The endothelium-dependent relaxant activities of acetylcholine in norepinephrine (NE)-precontracted aorta were increased in AE- and Amtreated rats. Particularly strong endothelium-dependent relaxant activities were observed in AE-treated (50 mg/kg) rats. The endothelium-independent relaxant activities of sodium nitroprusside in NE-precontracted aorta were not changed. The results of this study suggest that AE has both antihypertensive and end-organ protective effects in SHR.

The isolation rate of Escherichia (E.) coli in poultry litter was investigated at 44 broiler farms, 20 that used fresh litter and 24 that used recycled litter. The patterns of resistance to antibiotics of the E. coli isolates were compared. In litter sampled before the rearing period, the isolation rate of E. coli was higher at farms that used fresh litter; E. coli was present in the litter in 94.5% (35 out of 37 flocks tested) of the farms that used fresh litter vs. 51.2% (21 out of 41 flocks) of the farms that used recycled litter. The susceptibility of the 93 isolates of E. coli to 13 antibiotics was studied. Before the rearing period, E. coli isolates from the farms that recycled litter showed higher resistance rates than isolates from farms that replaced litter with fresh litter. Comparing the antibiotic resistance patterns of isolates from litter sampled before and at the end of the rearing period, the antibiotic resistance rates at the end of the rearing period increased dramatically compared with rates before the rearing period.

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.