Background: Streptococcus dysgalactiae subspecies equisimilis (SDSE) acts as an etiological agent for lameness, neurological signs, and high mortality in pigs. Despite its importance in pig industries and zoonotic potential, little is known about the effects of this pathogen. Objectives: This study aimed to determine the molecular characteristics and antimicrobial resistance of SDSE strains isolated from diseased pigs. Methods: A total 11 SDSE isolates were obtained from diseased pigs. Bacterial identification, PCR for virulence genes, emm typing, and antimicrobial resistance genes, multilocus sequence typing, and antimicrobial susceptibility test were performed. Results: Nine isolates were from piglets, and 8 showed lameness, sudden death, or neurological signs. The isolates were PCR-positive for sla (100%), sagA (100%), and scpA (45.5%), and only 1 isolate amplified the emm gene (stL2764). Eight different sequence types were detected, categorized into 2 clonal complexes and 4 singletons. All the isolates in this study were included in a small cluster, which also contained other strains derived from humans and horses. The minimum inhibitory concentrations for the tested beta-lactams were low, while those for macrolides, tetracyclines, and fluoroquinolones were relatively high. PCR analysis of the macrolide and tetracycline resistance genes demonstrated that the isolates carried erm(B) (18.2%, n = 2), mef(A/E) (9.1%, n = 1), tet(M) (18.2%, n = 2), and tet(O) (90.2%, n = 10). Two isolates presented a mutation in parC, which is associated with fluoroquinolone resistance. Conclusion This study provided insight into swine-derived SDSE, as it is related to veterinary medicine, and elucidated its zoonotic potential, in the context of molecular epidemiology and antimicrobial resistance in public health.

A 12-month-old domestic rabbit died suddenly without specific clinical signs. Gross examination revealed irregular yellowish hepatic nodules with pus in the submandibular muscles, lungs, uterus, and small intestines. Histopathological examination of the liver showed granulomatous inflammation with acid-fast-positive bacteria. Mycobacterium bovis SB1040 was identified by polymerase chain reaction and spoligotyping, and Pasteurella multocida was isolated from the multiple lesions. This report demonstrates the pathological features of rare bovine tuberculosis (bTB) in a domestic rabbit, the first case in the Republic of Korea. To ensure public safety, we recommend routine monitoring of rabbits to control the incidence of bTB.

This study describes pathological, immunohistochemical, and bacteriological findings in adult dogs and fetuses naturally infected with Brucella (B) canis. A total of 42 dogs including 40 dogs and 2 aborted fetuses were examined. The most common gross lesions in infected dogs were swelling of lymph nodes and spleen. The testes showed marked swelling with multifocal to diffuse reddish discoloration. The most significant histopathological lesions were observed in the placenta. Placental trophoblasts were markedly hypertrophied due to the accumulation of intra-cellular gram-negative bacteria. Lymphocytic inflammation of varying severity was observed in the reproductive organs such as male testis, epididymis, and prostate gland and female uterus. Strong immunolabelling was observed in the cytoplasm of most trophoblasts in the placental tissues using immunohistochemistry. However, immunohistochemical staining did not demonstrate any organisms in other organs of dogs and fetuses. B. canis isolates were most frequently obtained from the whole blood (82.5%) and superficial inguinal lymph node (77.5%) in both sexes. In addition, the isolation rate was higher in male genital organs than in those of females. Hence, management of male dogs is most important because infected dogs can play a role as carriers.

Abstract: This paper describes the development of neurological signs of two prematurely born calves four days after birth. The pathological examination results indicated fibrinopurulent polyserositis, including meningoencephalitis with suppurative bronchopneumonia. Bovine viral diarrhea virus subtype 2a was detected in most of the internal organs, and the bacterial colonies cultured from the samples were identified as Klebsiella (K.) pneumoniae. Molecular analysis via multilocus sequence typing identified a different K.pneumoniae isolate in each calf-type 14 in calf A and type 65 in calf B. This is the first report identifying K.pneumoniae sequence types 14 and 65 in cattle.

Monoclonal anti-enrofloxacin antibody was prepared for a direct competitive enzyme-linked immunosorbent assay (ELISA) and purification system using monoclonal antibody (mAb) coupled magnetic nanoparticles (MNPs). The IC50 values of the developed mAb for enrofloxacin (ENR), ciprofloxacin, difloxacin, sarafloxacin, pefloxacin, and norfloxacin were 5.0, 8.3, 9.7, 21.7, 36.0, and 63.7 ng/mL, respectively. The lowest detectable level of ENR was 0.7 ng/mL in the prepared ELISA system. To validate the developed ELISA in the food matrix, known amounts of ENR were spiked in meat and egg samples at 10, 20 and 30 ng/mL. Recoveries for ENR ranged from 72.9 to 113.16% with a coefficient of variation (CV) of 2.42 to 10.11%. The applicability of the mAb-MNP system was verified by testing the recoveries for ENR residue in three different matrices. Recoveries for ENR ranged from 75.16 to 86.36%, while the CV ranged from 5.08 to 11.53%. Overall, ENR-specific monoclonal antibody was prepared and developed for use in competitive to ELISAs for the detection of ENR in animal meat samples. Furthermore, we suggest that a purification system for ENR using mAb-coupled MNPs could be useful for determination of ENR residue in food.
Animals ; Ciprofloxacin ; Enzyme-Linked Immunosorbent Assay* ; Inhibitory Concentration 50 ; Meat ; Nanoparticles* ; Norfloxacin ; Ovum ; Pefloxacin

Mesenchymal stem cells (MSCs) have ability to differentiate into multi-lineage cells, which confer a great promise for regenerative medicine to the cells. The aim of this study was to establish a method for isolation and characterization of adipose tissue-derived MSC (pAD-MSC) and bone marrow-derived MSC (pBM-MSC) in pigs. Isolated cells from all tissues were positive for CD29, CD44, CD90 and CD105, but negative for hematopoietic stem cell associated markers, CD45. In addition, the cells expressed the transcription factors, such as Oct4, Sox2, and Nanog by RT-PCR. pAD-MSC and pBM-MSC at early passage successfully differentiated into chondrocytes, osteocytes and adipocytes. Collectively, pig AD-MSC and BM-MSC with multipotency were optimized in our study.
Adipocytes ; Adipose Tissue ; Bone Marrow ; Chondrocytes ; Hematopoietic Stem Cells ; Mesenchymal Stromal Cells ; Osteocytes ; Regenerative Medicine ; Swine ; Transcription Factors

Streptococcus dysgalactiae subspecies equisimilis (SDSE) is an emerging pathogen in animals and humans. Herein, we describe two clinical swine cases of SDSE infection presenting with lameness, neurological signs, or sudden death. Pathological examination indicated suppurative arthritis, encephalitis, and multifocal abscesses in kidney and heart. The β-hemolytic colonies obtained from joint samples of each case were identified as SDSE. The two isolates had low minimum inhibitory concentrations for β-lactams, and they presented the same virulence gene profile (slo⁻/sagA⁺/pSTKP8⁺). Molecular analysis by multilocus sequence typing identified the SDSE isolates from cases 1 and 2 as sequence types 315 and 252, respectively.
Abscess ; Animals ; Arthritis, Infectious ; Death, Sudden ; Encephalitis ; Heart ; Humans ; Joints ; Kidney ; Microbial Sensitivity Tests ; Multilocus Sequence Typing ; Streptococcus ; Swine ; Virulence

Eight rabbits exhibited head tilt and subsequently died. At necropsy, three rabbits had crusty deposits in ears and four had reddish lungs. The main histopathological features were severe diffuse suppurative meningoencephalitis (75.0% of rabbits), fibrinopurulent pneumonia (37.5%), and otitis externa (37.5%). Pasteurella multocida (P. multocida) was isolated from brains, ears, and lungs. The capsular serogroups of the isolates were untypable. Based on histopathological features and bacterial analysis results, the rabbits were diagnosed as P. multocida infection. P. multocida infections might result in considerable economic loss in commercial rabbit production facilities in Korea.
Brain ; Ear ; Head ; Korea ; Lung ; Meningoencephalitis ; Otitis Externa ; Pasteurella Infections ; Pasteurella multocida ; Pasteurella ; Pneumonia ; Rabbits ; Serogroup

An 8-year-old female Eurasian otter (Lutra lutra) reared in a wetland center, died 2 h after sudden onset of astasia and dyspnea despite medical treatment. Gross examination of internal organs revealed 10 adult filarioid nematodes in the right ventricle of the heart and three between the left and right cerebral hemispheres. All nematodes were identified as Dirofilaria immitis by direct microscopy and polymerase chain reaction assay. Histopathological observation revealed multifocal hemorrhage in the cerebral subarachnoid space and focal necrosis with hemorrhagein the cerebellar parenchyma. Although rare, veterinarians should consider cerebral dirofilariasis as a differential diagnosis in unexplained neurological cases.
Adult ; Animals ; Brain ; Cerebrum ; Child ; Diagnosis, Differential ; Dirofilaria immitis ; Dirofilaria ; Dirofilariasis ; Dyspnea ; Female ; Heart ; Heart Ventricles ; Hemorrhage ; Humans ; Korea ; Microscopy ; Necrosis ; Otters ; Polymerase Chain Reaction ; Subarachnoid Space ; Veterinarians ; Wetlands

Two 12-month-old cattle with anthelmintics containing trichlorfon the day before death presented to the Animal and Plant Quarantine Agency for diagnosis. In necropsy, they revealed enlargement of the spleens, redness of mucosa and serosa in stomachs and intestines, and friable kidneys. Histopathologically, hemorrhages in the spleens, omasums, abomasums, and intestines as well as renal tubular necrosis were observed. Trichlorfon was detected at above the lethal dose in the ruminal contents. Based on these findings, we diagnosed this case as death caused by trichlorfon poisoning.
Abomasum ; Animals ; Anthelmintics ; Cattle ; Death, Sudden ; Diagnosis ; Hemorrhage ; Humans ; Infant ; Intestines ; Kidney ; Mucous Membrane ; Necrosis ; Omasum ; Organophosphate Poisoning ; Organophosphates ; Plants ; Poisoning ; Quarantine ; Serous Membrane ; Spleen ; Stomach ; Trichlorfon