• Journal of Veterinary Science
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• v.21 no.5
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• pp.64.1-64.14
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• 2020

Background: Canine distemper virus (CDV) infection results in high morbidity and mortality in dogs. There has been no report about Isolation of Korean CDV since 1980 in Korea. Objectives: To investigate the biological properties and the genetic characterization of Korean CDV. Methods: Vero cells expressing dog signaling lymphocyte activation molecule (dSLAM) gene named as Vero/dSLAM were used to isolate CDV using 17 samples. Diagnostic methods such as cytopathic effects, immunofluorescence assay, peroxidase linked assay, electron microscopy, rapid immunodiagnostic assay, and reverse transcription polymerase chain reaction were used to confirm the Korean CDV isolate as a CDV. The genetic analysis was performed through cloning and sequencing of hemagglutinin gene of CDV isolate. Results: A virus propagated in Vero/dSLAM cell was confirmed as CDV (CD1901 strain) based on the above methods. The CD1901 strain showed the highest viral titer (10^5.5 50% tissue culture infectious dose [TCID₅₀]/mL) in the Vero/dSLAM cells at 4 days post inoculation, but did not form a fork on chorioallantoic membrane of 7-day-old egg. Ribavirin, a nucleotide analogue anti-viral agent, inhibits moderately the Korean CDV propagation in the Vero/dSLAM cells. The nucleotide and amino acid sequences of the H gene of CD1901 strain were compared with those of other CDV strains. The CD1901 strain belonged to Asia 1 group and had the highest similarity (99.9%) with the BA134 strain, which was isolated in China in 2008. Conclusions: We constructed successfully Vero/dSLAM and isolated one Korean CDV isolate (CD1901 strain) from a naturally infected dog. The CD1901 strain belonged to Asia 1 genotype.

• Korean Journal of Veterinary Research
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• v.62 no.3
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• pp.24.1-24.7
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• 2022

Incidences of major feline viral diseases provide basic information for preventing viral disease in cats. Despite the growing interest in feline viral diseases, sero-surveillances have been lacking. In this study, we analyzed the diagnoses of feline viral diseases and conducted a sero surveillance of feline panleukopenia virus (FPV), feline calicivirus (FCV), feline herpesvirus-1 (FHV-1), and feline infectious peritonitis virus (FIPV) in Korean cats. Of the 204 confirmed cases since 2015, the numbers of diagnoses for FPV, FIPV, FCV, feline influenza virus, and FHV-1 were 156, 32, 12, 3, and 1 case, respectively. In total, 200 sera, collected between 2019 and 2021, were screened for the presence of antibodies against FPV, 2 FCVs, FHV-1, and FIPV using a hemagglutination inhibition test and a virus-neutralizing assay (VNA). The overall seropositive rates in cats tested for FPV, the 2 FCVs, FHV-1, and FIPV were 92.5%. 42.0%, 37.0%, 52.0%, and 14.0%, respectively. A low correlation (r = 0.466) was detected between the VNA titers of 2 FCV strains. The highest incidence and seropositive rate of FPV reveal that FPV is circulating in Korean cats. The low r-value between 2 FCVs suggests that a new feline vaccine containing the 2 kinds of FCVs is required.

• Korean Journal of Veterinary Service
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• v.41 no.2
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• pp.91-95
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• 2018

Polioencephalomalacia (PEM) is a neurologic disease of ruminants diagnosed by pathological approach. There is very little information available to understand bovine PEM in Korea. In this study, we investigated the diagnostic rate and pathological features of PEM in 334 necropsied cases of cattle submitted to the Animal and Plant Quarantine Agency in Korea from 2015~2017. PEM was diagnosed only in 13 (3.9%) Hanwoo, the Korean native cattle, and sporadically occurred in our country. The disease was the most diagnosed in fall season, and the age of the cows ranged from 1 month to 3 year. In all PEM cases, softening, and yellow discoloration of the gray matter in the cerebrum and fluorescence at the sites using ultraviolet illumination were grossly observed. Microscopically abundance of glial cells with vacuolar large cytoplasm and neuronal necrosis were commonly observed. This study suggests that future studies are necessary to identify the cause and pathogenesis for the control of PEM in our country.

• Journal of Veterinary Science
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• v.21 no.4
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• pp.63.1-63.9
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• 2020

Background: Canine adenovirus type 2 (CAV-2) induces infectious laryngotracheitis in members of the family Canidae, including dogs. To date, no ELISA kits specific for CAV-2 antibody have been commercialized for dogs in Korea. Objectives: We aimed to develop new indirect enzyme-linked immunosorbent assay (I-ELISA) to perform rapid, accurate serological surveys of CAV-2 in dog serum samples. Methods: In total, 165 serum samples were collected from dogs residing in Chungbuk and Gyeongbuk provinces between 2016 and 2018. The Korean CAV-2, named the APQA1701-40P strain, was propagated in Madin-Darby canine kidney cells and purified in an anion-exchange chromatography column for use as an antigen for I-ELISA. The virus-neutralizing antibody titers of CAV-2 in the dog sera were measured by virus neutralization (VN) test. Results: We compared the results obtained between the VN and new I-ELISA tests. The sensitivity, specificity, and accuracy of new I-ELISA were 98.6%, 86.4% and 97.0% compared with VN test, respectively. New I-ELISA was significantly correlated with VN (r = 0.91). Conclusions: These results indicate that new I-ELISA is useful for sero-surveillance of CAV-2 in dog serum.

• Korean Journal of Veterinary Research
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• v.62 no.4
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• pp.29.1-29.7
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• 2022

Vaccination against Newcastle disease (ND) is the most effective means of controlling the disease, and these vaccines are commercialized only after their safety and effectiveness have been verified through tests that comply with Korean Standards of National Lot Release for Veterinary Biologics. This study investigated whether a relatively convenient and safe serological test can be used in place of the challenge test using highly virulent ND virus. Hemagglutination inhibition (HI) assay and enzyme-linked immunosorbent assay (ELISA) were considered positive of log₂ 2 or more and cutoff value of 200 or more, respectively, in both live and inactivated vaccines. However, when the antibody levels of the live and inactivated vaccines induced using the Ulster 2C, KBNP-C4152R2L, and K148/08 strains were compared, the antibody titers for inactivated vaccines were significantly higher than those for live vaccines in both the HI assay and ELISA. A strong positive correlation was observed between HI and ELISA antibody titers. The live vaccines corresponded to a survival rates of ≥ 80% and the inactivated vaccines corresponded to 100% survival rates. This study confirmed that standard efficacy tests can serve as serological tests, and can replace the challenge test and that the vaccine approval process can be improved.

• Korean Journal of Veterinary Service
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• v.36 no.3
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• pp.151-155
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• 2013

Since a large number of Akabane and bovine ephemeral fever (BEF) infection occurred in the southern part of Korea in 2010, recent information about seroprevalence of Akabane virus (AKAV) and bovine ephemeral fever virus (BEFV) has been required for preventing both diseases. In this study, serological assay against AKAV and BEFV using virus neutralization assay was conducted using 1,743 bovine sera collected from Namwon, Miryang, Yeongju and Uljin which located in Southern part of Korea from March to May in 2012. The overall seropositive rates for AKAV and BEFV were found to be 49.8% and 1.2%, respectively. The regional distribution of seroprevalence for AKAV ranged from 18.1% to 63.7%. Seroprevalences of AKAV were 63.7% in Miryang, 62.3% in Uljin, 50.7% in Namwon, and 18.1% in Yeongju. The seropositive rates for AKAV in southern part of Korea were higher than the annual average at the national level. On the other hand, seropositive rates of BEFV in four regions were from 0.3 to 3.1%. In detail, regional seroprevalences were 3.1% in Miryang, 2.0% in Uljin, and 1.7% in Yeongju, and 0.3% in Namwon. Even only one year after massive outbreaks, overall seropositive rates were very low, similar to the annual average at the nation level. This result indicates that many number of cattle infected with BEFV may be replaced by new born calf or cattle in farm may not be immunized with vaccines. To prevent another epidemic, a national wide warning should be issued and more aggressive control measure must be implied. Recent global warming phenomenon could lead to more vigorous activity of haematophagous vectors and it is possible that arboviral diseases such as AKAV and BEFV are increased. Therefore, continuous sero-monitoring and extensive vaccination combined with control of haematophagous vectors are important to effectively prevent and control diseases caused by AKAV and BEFV.

• Microbiology and Biotechnology Letters
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• v.46 no.3
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• pp.269-276
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• 2018

Rabies virus (RABV)-specific antibodies in animals and humans are measured using standard methods such as fluorescent antibody virus neutralization (FAVN) tests and rapid fluorescent focus inhibition tests, which are based on cell culture systems. An alternative assay that is safe and easy to perform is required for rapid sero-surveillance following mass vaccination of animals. Two purified monoclonal antibodies (4G36 and B2H17) against RABV were selected as capture and detection antibodies, respectively. A genetically modified RABV, the ERAGS strain, was propagated and concentrated by polyethylene glycol precipitation. Optimal conditions for the RABV antigen, antibodies, and serum dilution for a blocking enzymelinked immune sorbent assay (B-ELISA) were established. We evaluated the sensitivity, specificity, and accuracy of the B-ELISA using serum samples from 138 dogs, 71 raccoon dogs, and 25 cats. The B-ELISA showed a diagnostic sensitivity of 95.8-96.3%, specificity of 91.3-100%, and accuracy of 96.0-97.2% compared to the FAVN test. These results suggest that the B-ELISA is useful for sero-surveillance of RABV in dogs, raccoon dogs, and cats.

• Korean Journal of Veterinary Research
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• v.62 no.3
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• pp.19.1-19.6
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• 2022

Japanese encephalitis virus (JEV) and Akabane virus (AKAV) are mosquito-borne viruses that cause encephalitis and reproductive disorders in horses and cattle, respectively. There is no treatment for JEV or AKAV infections in animals. Therefore, we evaluated the antiviral activity of 18-mer amphipathic peptides in the 1b-4/21-C series on JEV and AKAV using Vero cells in vitro and evaluated their effects on JEV in mice. Of 6 peptides, 1b-4/21-C12 had the lowest IC₅₀ of 0.313 against JEV and its use as an antiviral against JEV and AKAV was examined. The IC₅₀ of 1b-4/21-C12 against JEV and AKAV was 0.78 and 1.14 µM, respectively. Mice treated with 5 or 2 mg/kg of 1b-4/21-C12 had 32% and 16% survival rates, respectively, and the surviving mice treated with 1b-4/21-C12 began to gain weight beginning 8 days post challenge with the virulent Nakayama strain. Moreover, 20 µM 1b-4/21-C peptide had no cytotoxic effects on Vero cells. Our in vitro and in vivo results indicate that 1b-4/21-C12 has antiviral activity against enveloped JEV and AKAV and might be useful as a therapeutic substance.

• Journal of the Korean Institute of Rural Architecture
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• v.17 no.1
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• pp.35-44
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• 2015

This study is regarding Rural village renovation project that improve the poor residential environment of backward rural district in Korea and the quality of life of the rural area residents. Especially, by comparing the Kyungbuk, Yeungju, Juchi village's case which was progressed by MAFRA (Ministry of Agriculture, Food and Rural Affairs) in 2014 for the demonstration project with the successful case MELAP(Model project on the Effective Utilization of Rural Land through the activation of internal potential element) which is one of the Rural area Development Program in German Federal Ministry of Baden-$W{\ddot{u}}rttemberg$, this essay attempts to suggest the improvement Plan of Rural village renovation project which will be developed forward.

• KOREAN POULTRY JOURNAL
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• v.47 no.7
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• pp.144-145
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• 2015

최근 정부는 "자유무역협정 체결에 따른 농어업인 등의 지원에 관한 특별법" 제6조에 따라 자유 무역협정의 이행으로 수입량이 급격히 증가하여 가격 하락의 피해를 입은 품목의 생산자에게 가격 하락의 일정 부분을 지원함으로써, 농업인 등의 경영안정을 도모하고 피해를 보전하기 위해 2015년도 FTA 피해보전직불제 사업시행지침을 발표했다. 세부 사항은 농림축산식품부 홈페이지(www.mafra.go.kr)를 통해 확인할 수 있다.