Pseudomonas aeruginosa is one of the most common pathogenic species associated with canine otitis externa (OE). Their resilience is achieved by forming a biofilm, which allows these bacteria to evade even the harshest of treatments. This study evaluated the in vitro synergistic efficacy of N-acetylcysteine (NAC) with different antimicrobial agents against P. aeruginosa isolated from dogs with OE to develop an effective treatment against P. aeruginosa. The antimicrobial activity was evaluated by the minimum inhibitory concentration test using the microdilution method. The efficacy of antibiofilm formation was evaluated using crystal violet stain method. The treatment solutions included NAC alone, and in synergy with enrofloxacin, polymyxin B, and gentamicin. NAC alone exhibited antimicrobial and antibiofilm abilities. On the other hand, the combination of NAC and the antibiotics did not show any significant synergistic effects against P. aeruginosa.

The mosquito-borne pathogen Zika virus may result in neurological disorders such as Guillain-Barré syndrome and microcephaly. The virus is classified as a member of the Flaviviridae family and its wide spread in multiple continents is a significant threat to public health. So, there is a need to develop animal models to examine the pathogenesis of the disease and develop vaccines. To examine the clinical profile during Zika virus infection, we infected neonatal and adult wild-type mice (C57BL/6 and Balb/c) and compared the clinical signs of African-lineage strain (MR766) and Asian-lineage strain (PRVABC59, MEX2-81) of Zika virus. Consistent with previous reports, eight-week-old female Balb/c mice infected with these viral strains showed changes in body weight, survival rate, and no neurologic signs, but demonstrated increases in the weights of spleens and hearts. However, one-day-old neonates showed significantly lower survival rate and body weight with the African-lineage strain than the Asian-lineage strain. These results confirmed the pathogenic differences between Zika virus strains. We also evaluated the clinical responses in neonatal and adult mice of different strains. Our findings suggest that these are useful mouse models for characterization of Zika virus for vaccine development.

Mammalian reovirus (MRV) causes respiratory and intestinal disease in mammals. Although MRV isolates have been reported to circulate in several animals, there are no reports on Korean MRV isolates from wildlife. We investigated the biological and molecular characteristics of Korean MRV isolates based on the nucleotide sequence of the segment 1 gene. In total, 144 swabs from wild animals were prepared for virus isolation. Based on virus isolation with specific cytopathic effects, indirect fluorescence assays, electron microscopy, and reverse transcription-polymerase chain reaction, only one isolate was confirmed to be MRV from a Korean roe deer (Capreolus pygargus). The isolate exhibited a hemagglutination activity level of 16 units with pig erythrocytes and had a maximum viral titer of 10⁵·⁷ 50% tissue culture infectious dose (TCID50)/mL in Vero cells at 5 days after inoculation. The nucleotide and amino-acid sequences of the partial segment S1 of the MReo2045 isolate were determined and compared with those of other MRV strains. The MReo2045 isolate had nucleotide sequences similar to MRV-3 and was most similar (96.1%) to the T3/Bat/Germany/342/08 strain, which was isolated in Germany in 2008. The MReo2045 isolate will be useful as an antigen for sero-epidemiological studies and developing diagnostic tools.

Feline panleukopenia virus (FPV) causes leukopenia and severe hemorrhagic diarrhea, killing 50% of naturally infected cats. Although intact FPV can serve as an antigen in the hemagglutination inhibition (HI) test, an accidental laboratory-mediated infection is concern. A non-infectious diagnostic reagent is required for the HI test. Here, we expressed the viral protein 2 (VP2) gene of the FPV strain currently prevalent in South Korea in a baculovirus expression system; VP2 protein was identified by an indirect immunofluorescence assay, electron microscopy (EM), Western blotting (WB), and a hemagglutination assay (HA). EM showed that the recombinant VP2 protein self-assembled to form virus-like particles. WB revealed that the recombinant VP2 was 65 kDa in size. The HA activity of the recombinant VP2 protein was very high at 1:2¹⁵. A total of 143 cat serum samples were tested using FPV (HI-FPV test) and the recombinant VP2 protein (HI-VP2 test) as HI antigens. The sensitivity, specificity, and accuracy of the HI-VP2 test were 99.3%, 88.9%, and 99.3%, respectively, compared to the HI-FPV test. The HI-VP2 and HI-FPV results correlated significantly (r = 0.978). Thus, recombinant VP2 can substitute for intact FPV as the serological diagnostic reagent of the HI test for FPV.

A seven-year-old, castrated male, Korean domestic shorthair cat was referred because of a kidney abnormality. Radiography revealed left renal agenesis and right kidney enlargement. Ultrasonography and computed tomography (CT) showed amorphous calcified materials in a cyst-like lesion of the right kidney. In the excretory phase of the CT images, the lesion was opacified with contrast materials, indicating communication with the collecting system. Based on these findings, the cat was diagnosed with a calyceal diverticulum. A calyceal diverticulum may cause various clinical symptoms related to the urinary system. The excretory phase of CT is useful for diagnosing a calyceal diverticulum.

The axolotl has extraordinary regeneration capacity compared to other vertebrates. This remarkable potential has been attributed to its life-long neoteny, characterized by the exhibition of embryonic characteristics at the adult stage. A recent study provided a detailed morphological analysis of the sperm morphology of the Ambystoma mexicanum using routine and detailed histological techniques. The primary purpose of the present study is to describe a simple and inexpensive method for evaluating the morphology of axolotl sperm. In this study, spermatophore structures were collected and spread on slides and air-dried. The slides were stained with periodic acid Schiff, toluidine blue, Masson’s trichrome, Giemsa, Spermac, and Diff-Quik dye for a morphological examination. The slides were coated with gold/palladium for a scanning electron microscopy examination. The sperm of the axolotl consisted of an elongated head, a neck, and a flagellum covered with an undulating membrane. The lengths of the midpiece, tail, and head were 8.575 µm, 356.544 µm, and 103.661 µm, respectively. In the flagellum part, the wavy membrane structure, whose function has not been explained, surrounds the tail. The data obtained from this study will constitute an important step in designing future research on the reproductive and regeneration capacity of the axolotl.

From April 2014 to September 2015, 153 piglets from 52 farms in Jeju were diagnosed with porcine epidemic diarrhea (PED). The major PED cases were focused on suckling piglets (144 piglets, 94.1%), particularly in 1-7-day-old piglets. Histopathologically, severe villous atrophy was observed in the small intestine, especially in the jejunum and ileum. The mean villous height to crypt depth ratios of the jejunum and ileum were 1.4:1 and 1.5:1, respectively. The major histopathologic findings of the small intestine were cytoplasmic vacuolation, cuboidalization, squamation, and exfoliation of the mucosal enterocytes in the villi. The cytoplasmic vacuolations in the enterocytes were the most prevalent lesions in the small intestine and were more severe in the ileum than in the jejunum. According to immunohistochemistry methods, the PED virus (PEDV) antigens were presented in the cytoplasms of the enterocytes, and were distributed more prevalently in the ileum than in the jejunum. PEDV antigens were also detected in the colon of 29 piglets (19.5%). Sequence comparison and phylogenetic analysis indicated that 12 PEDV had more than a 98.9% homology with each other. These PEDV strains were highly homologous with the genogroup 2 North American group.

The classification of the bone pieces excavated from Gasan-ri archaeological site Ⅰ in Jinju, presumed to be relics was investigated macroscopically. The remains of the animal bone were 3 classes (Mammalia, Aves, Amphibia), 5 orders (Carnivora, Artiodactyla, Passeriformes, Rodentia, Salientia), and 6 species (Sus scrofa, Cervidae sp., Nyctereutes procyonides, Passeriformes sp., Rattus norvegicus caraco, Rana nigromaculata). The total weight of the animal bone remains was 1,002.80 g, with the identified bones comprising 975.30 g and an identification rate of 97.26%. A total of 447 animal bone fragments were identified, including 204 bone pieces of S. scrofa (468.00 g, 47.99%), 102 bone pieces of Cervidae sp. (453.79 g, 46.53%), 68 bone pieces of R. nigromaculata (4.69 g, 0.48%), 59 bone pieces of N. procyonides (47.14 g, 4.83%), 9 bone pieces of Passeriformes sp. (0.98g, 0.10%), and 5 bone pieces of Rattus norvegicus caraco (0.70 g, 0.07%). The bone pieces of the animal relics consisted of 81 skull (18.12%), 161 axial skeleton (36.02%), 64 forelimb (14.32%), and 141 hindlimb (31.54%) fragments. The archaeological significance of the animal bones excavated in this investigation was that wild boars and deer were presumed to have been mainly used animals in the Gasan-ri area of Jinju during the Three Kingdoms period.

A 12-year-old neutered male Golden Retriever presented with a progressively enlarging mass in the submandibular region. Histopathological diagnosis confirmed lymphangiosarcoma with metastasis to the liver and spleen. The pleomorphic neoplastic endothelial cells of the tumor grow directly on bundles of dermal collagen, forming numerous clefts and interconnecting channels that are devoid of conspicuous hematic elements. As lymphangiosarcoma is an uncommon malignant neoplasm, the number of previously reported cases and information of the tumor is limited. The present report describes the clinical history and histopathological diagnosis of a progressive lymphangiosarcoma in the submandibular region with metastases in a dog.

The objective of this study was to evaluate the beneficial effects of the short-term application of insect-based diet in canine allergic dermatitis. Total 19 atopic dogs with concurrent cutaneous adverse food reactions were enrolled and classified into 3 groups. The treatment group (n = 7) was fed insect-based diet, the positive control group (n = 6) was fed salmon-based diet, and the negative control group (n = 6) was fed commercial or homemade diet for 12 weeks. The degree of skin lesions was evaluated based on canine atopic dermatitis extent and severity index (CADESI-4). Additionally, transepidermal water loss (TEWL) and pruritus visual analog scale were evaluated. All indices were evaluated every 4 weeks after the initial administration of hypoallergenic diets. In the treatment group, significant decrease in the CADESI-4 score was observed at 8 weeks compared to the baseline score (p = 0.031). There were significant differences in the CADESI-4 score between the groups at 8 weeks (p = 0.008), 12 weeks (p = 0.012), and TEWL at 12 weeks (p = 0.022). This preliminary result demonstrates the potential hypoallergenicity of an insect-based diet through features that diminish cutaneous lesions and skin barrier dysfunction.