• 대한수의학회지
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• 제61권2호
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• pp.13.1-13.8
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• 2021

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 10^5.7 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.

• 한국동물위생학회지
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• 제36권3호
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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.

• Toxicological Research
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• 제28권4호
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• pp.279-288
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• 2012

Rats were administered zearalenone (ZEA) via gavage at dosages of 0, 1, 5, and 30 mg/kg for 36 days. On treatment day 8, inactivated porcine parvovirus vaccine (Vac) was injected intraperitoneally. Antibody production against porcine parvovirus was then measured as a function of ZEA treatment. Compared to the vaccine alone, ZEA treatment, with or without Vac, decreased the serum level of IgG. The level of IgM decreased in all ZEA groups at day 22, but the decrease was sustained only in the medium-dose ZEA group at day 36. The level of IgA was unchanged in the Vac only and ZEA groups at day 22, but was decreased in the 5 mg/kg ZEA plus Vac group compared to the Vac only group at day 36. The level of IgE was decreased by all doses of ZEA at day 22, but was unaffected in ZEA plus Vac groups compared to the Vac only group. The levels of IL-1 in the thymus and spleen; INF-${\gamma}$ in serum; IL-2, IL-6, and IL-10 in the thymus; and IL-10 and IFN-${\gamma}$ in the spleen decreased after ZEA administration. Furthermore, the levels of IL-$1{\beta}$ in the spleen and mesenteric lymph node, IL-$1{\beta}$ in the thymus, IL-2 in the thymus and spleen, IL-6 in the thymus, IL-10 and IFN-${\gamma}$ in the spleen, and GM-CSF and TNF-${\alpha}$ in the thymus decreased after vaccination in rats exposed to ZEA. In conclusion, these results suggest that ZEA exposure via drinking water can cause an immunosuppressive effect by decreasing immunoglobulins in serum and cytokines in lymphoid organs.

• Asian-Australasian Journal of Animal Sciences
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• 제26권4호
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• pp.588-595
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• 2013

Mesenchymal stem cells (MSCs) are often known to have a therapeutic potential in the cell-mediated repair for fatal or incurable diseases. In this study, canine umbilical cord MSCs (cUC-MSCs) were isolated from umbilical cord matrix (n = 3) and subjected to proliferative culture for 5 consecutive passages. The cells at each passage were characterized for multipotent MSC properties such as proliferation kinetics, expression patterns of MSC surface markers and self-renewal associated markers, and chondrogenic differentiation. In results, the proliferation of the cells as determined by the cumulative population doubling level was observed at its peak on passage 3 and stopped after passage 5, whereas cell doubling time dramatically increased after passage 4. Expression of MSC surface markers (CD44, CD54, CD61, CD80, CD90 and Flk-1), molecule (HMGA2) and pluripotent markers (sox2, nanog) associated with self-renewal was negatively correlated with the number of passages. However, MSC surface marker (CD105) and pluripotent marker (Oct3/4) decreased with increasing the number of subpassage. cUC-MSCs at passage 1 to 5 underwent chondrogenesis under specific culture conditions, but percentage of chondrogenic differentiation decreased with increasing the number of subpassage. Collectively, the present study suggested that sequential subpassage could affect multipotent properties of cUC-MSCs and needs to be addressed before clinical applications.

• 한국동물위생학회지
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• 제44권3호
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• pp.133-140
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• 2021

This study was aimed to investigate the prevalence and antimicrobial resistance of Pseudomonas spp. isolated from bovine mastitis milk samples. A total of 50 (4.9%) Pseudomonas spp. was isolated from 1,023 samples, those collected between 2018 and 2021, derived from 110 dairy farms. The prevalence of the identified species of Pseudomonas isolates was as follows; P. aeruginosa (70.0%), P. fluorescens (14.0%), P. putida (10.0%), P. fragi (4.0%), and P. chlororaphis (2.0%). Most of somatic cell counts in the quarter milk carrying Pseudomonas spp. were less than 3,000,000 cell/ml (90.0%). The isolates of Pseudomonas spp. showed high susceptibility to cefepime (98.0%), ciprofloxacin (98.0%), ceftazidime (96.0%), and colistin (96.0%). The rate of antibiotic resistance in the isolates was highest to ceftiofur (92.0%), followed by the resistance rate to chloramphenicol (86.0%) and trimethoprim/sulphamethoxazole (80.0%). In addition, there is a remarkable difference in antimicrobial resistance pattern among Pseudomonas species. P. aeruginosa and P. putida showed a similar resistance pattern, whereas P. fluorescens showed exceptionally lower resistance to trimethoprim/sulphamethoxazole and chloramphenicol than that of the other species. This study showed that prevalence of Pseudomonas spp. other than P. aeruginosa were 30.0% in bovine mastitis milk, and the occurrence rate of antibiotic resistance were similar or higher level, compared with the previous reports on the mastitisderived Pseudomonas spp. isolated in Korea.

• 한국동물위생학회지
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• 제44권4호
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• pp.315-320
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• 2021

To analyze prevalence of mycotoxins, a total of 74 feedstuff samples were collected from silos (n=37) and hoppers (n=37) in nine pig farms. Six mycotoxins were tested with commercialized ELISA kits. All samples were contaminated with four or more mycotoxins. Zearalenone was detected in all of the tested samples. Ochratoxin, deoxynivalenol and H-2/HT-2 toxin were detected in more than 90% of the samples. And also, fumonisin was positive in 89.2% of the samples from the silos, 75.2% from the hoppers, respectively. On the other hand, aflatoxin was detected in about 40% of the samples. When the behavior of lactating sows was observed, possible mycotoxicosis was suspected. It was confirmed that their feedstuffs were contaminated with high levels of mycotoxins such as ochratoxin and T-2/HT-2 toxin. After cleaning the feedline, the clinical symptoms in sows suspected with mycotoxicosis were disappeared. Although mycotoxin concentration in most of the feedstuffs was below the acceptance level, these data indicate that what are required is more monitoring and continuous management for mycotoxins in pig feedstuffs.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• 제5권2호
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• pp.60-67
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• 2024

Hitchhiker insect species from international vessels entering Korea in 2022 were monitored. A total of 947 samples of hitchhiker insects were collected using a simple collection method by hand. Among them, 856 individuals were classified as 374 species of 86 families in 10 orders through integrative analysis with DNA barcoding and morphological examination. The rest 91 individuals were identified only to the family level. As a result of examining the distribution of the 374 species (856 individuals), 38 species (71 individuals) were confirmed as not-distributed species in Korea, including six species (11 individuals) as 'regulated species' listed by the Korean Animal and Plant Quarantine Agency. Of 38 not-distributed species, 10 species were detected multiple times (at least twice). Accordingly, it is necessary to strengthen monitoring of the area around the port of entry along with continuous surveillance to prevent invasion of species detected multiple times. For monitoring alien hitchhiker insect species, this study provided detection information and biological data for alien species.

• 대한수의학회지
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• 제43권3호
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• pp.449-456
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• 2003

The VP2 gene of aquatic birnavirus, Korean isolate (GC-1) was cloned and expressed using the baculovirus expression system. The VP2 gene and VP2 partial gene, which contained a neutralizing epitope, were constructed for recombinant transfer vectors, for baculovirus expression. The expressed recombinant proteins were confirmed by indirect immuno fluorescence antibody (IFA), SDS-PAGE and Western blot. The level of expression was checked at regular time using IFA and Western blot. To measure the neutralizing activity of recombinant proteins against GC-1 strain, the antisera against recombinant proteins were produced by using guinea pigs. The result showed that the antisera neutralized the GC-1 strain. However, the neutralizing titer was higher in antisera against the VP2 gene expressed recombinant protein than that of VP2 partial gene recombinant protein.

• 한국보건간호학회지
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• 제35권3호
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• pp.401-414
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• 2021

Purpose: The purpose of this study was to compare the practice of quarantine guidelines and psychological influence between the young (aged under 64 years) and the elderly (aged over 65 years) groups during the coronavirus disease 19 (COVID-19) pandemic. Method: The data of this study were obtained from the Community Health Survey, 2020, Korean Disease Control and Prevention Agency. A total of 229,296 (young group: 156,314, elderly group: 72,812) participants were included in this study. Independent t-test, chi-square test and descriptive analysis were used for analyzing the data. Result: Elderly group showed lower adherence to wearing face-mask, maintaining social distance when outgoing and practicing handwashing rules than the young group. The elderly group showed a higher level of psychological influence than the young group. In addition, the elderly group had fewer supporters when they were isolated than the young group. Also, the elderly had difficulties in following the quarantine guidelines related to COVID-19. Conclusion: To prevent infection and death from COVID-19 in the elderly, proper education and support programs are needed. Also, support groups should be prepared and applied to relieve their psychological impact related to COVID-19.

• Journal of Species Research
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• 제12권2호
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• pp.189-196
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• 2023

We monitored the hitchhiker insect pests from the international vessels entering into Korea in 2021. As a result, total of 581 individuals were detected by the survey based on visual inspection with naked eye. Among them, 500 individuals were identified as 244 species of 65 families under 11 orders through the integrative taxonomic method with DNA barcoding and morphological reexamination, but the remaining 81 individuals were classified as only to the family level. Of the 244 species identified, 26 species were determined to be not-distributed species in Korea (two Orthoptera, two Hemiptera, one Megaloptera, five Coleoptera, three Hymenoptera, and 13 Lepidoptera). Among them, two species, Sagra femorata (Chrysomelidae, Coleoptera) and Dendrolimus punctatus (Lasiocampidae, Lepidoptera), were discovered as 'Regulated species' listed by Animal and Plant Quarantine Agency, South Korea. Therefore, we reported on the 26 not-distributed species in Korea and provided inanimate pathway information such as navigation routes on the vessels hitchhiking the species, state of the samples at the time of detection, identification results and original distribution for the detailed monitoring and the risk analysis on the species.