• Korean Journal of Veterinary Service
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• v.20 no.2
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• pp.195-203
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• 1997

Fecal samples were collected from 47 calves with diarrhea and 12 clinically normal co-h-abitants, and tested for virus using MDBK cell cultures. Three cytopathic viruses were isolated from 8 fecal samples obtained from diarrheic calves. The isolated viruses were neutralized by bovine coronavirus hyperimmune serum In plaque reduction assay and were detected in the cytoplasm of MDBK cell by bovine coronavirus hyperimmune serum using immunofluorescence staining. The viruses agglutinated mouse erythrocytes only among the various animal erythrocytes tested and new isolates were identified as bovine coronavirus.

• Journal of Microbiology and Biotechnology
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• v.2 no.2
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• pp.122-128
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• 1992

Post-translational modifications of the nucleocapsid protein of bovine coronavirus (Quebec strain) were investigated. Coronavirions were radiolabelled in vivo with inorganic $[^{32}P]$orthophosphate and analysed by SDS-PAGE, followed by autoradiography. A single polypeptide with a migration rate of 55 KDa was identified by metabolic phosphate labelling, demonstrating that the nucleocapsid protein of bovine coronavirus was a phosphoprotein. A gene encoding the nucleocapsid protein was inserted immediately downstream from the polyhedrin promoter of Autographa californica nuclear polyhedrosis baculovirus. Spodoptera frugiperda cells infected with this recombinant baculovirus synthesized a 55 KDa polypeptide, as demonstrated by immunoprecipitation with anti-nucleocapsid monoclonal antibody. The recombinant nucleocapsid protein synthesized in Spodoptera cells could also be labelled by $[^{32}P]$orthophosphate. Phosphoamino acid analysis showed that both serine and threonine residues were phosphorylated in authentic, as well as in recombinant nucleocapsid proteins, with a relative phosphorylation ratio of 7:3. Our studies demonstrated that the nucleocapsid protein of bovine coronavirus was a serine and threonine-phosphorylated protein and that Spodoptera insect cells were able to properly phosphorylate the relevant foreign proteins.

• Korean Journal of Veterinary Research
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• v.38 no.3
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• pp.581-588
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• 1998

Eight monoclonal antibodies(MAbs) against bovine coronavirus(BCV) were produced and characterized. Three MAbs(1G9, 4H12, 5C1) specific to the S glycoprotein and two HE glycoprotein-specific MAbs(2A5, 5G4) were found to neutralize the BCV in fluorescence focus neutralization(FFN) test. Two HE-specific MAbs from the neutralizing MAbs inhibited the hemagglutinating activity of the BCV. None of the N protein-specific MAbs(1C1, 5A12, 6H1) neutralized the virus infectivity. Bovine coronavirus and mouse hepatitis virus, which belong to group II coronaviruses, were differentiated from other groups of coronaviruses(porcine transmissible gastroenteritis virus, porcine epidemic diarrhea virus, canine coronavirus) by all MAbs in fluorescence antibody test(FA), but not in FFN test.

• Korean Journal of Veterinary Service
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• v.22 no.3
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• pp.239-245
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• 1999

The reverse transcriptase polymerase chain reaction (RT-PCR) was used for the detection of bovine coronavirus (BCV) in fecal samples by using reverse transcriptase and two primers which flanked M gene sequence of 407bp. RT-PCR detected bovine coronavirus specifically, but did not detect mouse hepatitis virus (MHV), transmissible gastroenteritis virus (TGEV), and bovine rotavirus (BRV). The M gene sequences of MHV are homologus to that of BCV, but minor differences exist in the primer regions, preventing annealing of the primers. Detection of BCV using RT-PCR was compared with ELISA and the agreement of BCV detection by RT-PCR and ELISA was 95.3%. RNA detection in positive clinical specimens was significantly better by PCR than immunological detection of BCV by ELISA.

• Korean Journal of Veterinary Service
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• v.46 no.2
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• pp.147-156
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• 2023

Between February 2020 and September 2021, a total of 452 dairy calves with diarrhea were investigated across 17 dairy farms in Gyeonggi province, Korea, using a rapid diagnostic kit. The study aimed to examine the infection rates of major pathogens causing diarrhea in dairy calves, categorizing them by season, age, and birth month. Additionally, logistic regression analysis was conducted to investigate the factors affecting the infection rate. The infection rates of the major pathogens causing infectious diarrhea in dairy calves, including bovine rotavirus, bovine coronavirus, Cryptosporidium, and E. coli, are influenced by season, age, and birth month. Bovine coronavirus and Cryptosporidium showed variations in infection rates according to season, age, and birth month, while bovine coronavirus was influenced by age and birth month, and E. coli showed variations in infection rates based on age. Furthermore, in the analysis of risk factors influencing the infection rates of these pathogens, age and birth month were identified as risk factors for bovine rotavirus, bovine coronavirus, and Cryptosporidium.

• Journal of Practical Agriculture & Fisheries Research
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• v.5 no.1
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• pp.57-63
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• 2003

The bovine rotavirus(BRV), bovine coronavirus(BCV) and bovine viral diarrhea virus(BVDV) are main viruses of bovine viral diarrhea disease. These viruses could be rapidly amplified by the reverse transcriptase polymerase chain reaction(RT-PCR). This study was conducted to develop rapid and accurate diagnostic methods of these viral diseases by multiplex RT-PCR. Specific primers were designed based on the sequences reported by Chang KO et. al. (1997) and Schroeder BA, et. al. (1990), RNA were prepared from the cultured viruses, first-stranded DNAs were synthesised by reverse transcriptase. PCR were conducted to amplify specific regions of the viruses by multiplex. Three bands such as 1,062bp for BRV, 458bp for BCV, and 300bp for BVDV were successfully produced by multiplex RT-PCR. In conclusion, this result suggested that these viruses could be diagnosed rapidly and accurately by multiplex RT-PCR.

• Journal of Microbiology and Biotechnology
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• v.2 no.3
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• pp.174-182
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• 1992

The hemagglutinin-esterase glycoprotein (HE) gene of bovine coronavirus, coupled with a simian virus 40 early promoter and polyadenylation signal, was inserted into a human adenovirus transfer vector. The transfer vector was used to co-transfect 293 cells along with adenovirus genomic DNA. The hemagglutinin-esterase transcription unit was rescued into the adenovirus genome by homologous in vivo DNA recombination between the vector plasmid DNA and the adenovirus genomic DNA, and a recombinant adenovirus was isolated by several rounds of plaque assays. Thus the recombinant adenovirus carries the hemagglutinin-esterase gene in the early transcription region 3 (E3) of the adenovirus genome in the parallel orientation to the E3 transcription. The recombinant adenovirus synthesized the HE polypeptide in HeLa cells as demonstrated by immunoprecipitation with anti-coronavirus rabbit antisera. The recombinant HE polypeptide could be labelled by $[^3H]$glucosamine, demonstrating that the recombinant HE was glycosylated. Cells expressing the HE polypeptide exhibited hemadsorption activity when incubated with mouse erythrocytes. The HE was transported to the plasma membrane as shown by the cell surface immunofluorescence, indicating that the recombinant HE polypeptide retained its biological activities. Potential for the use of infectious recombinant adenovirus as a live virus-vectored vaccine candidate for bovine coronavirus disease is discussed.

• Korean Journal of Veterinary Service
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• v.32 no.3
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• pp.209-213
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• 2009

This survey was carried out to investigate the prevalence of bovine coronavirus (BCV) infection for the calves in Seosan-Taean Area. A total of 75 samples were collected from fecal swab to detect BCV by RT-PCR Results obtained through the survey were as follows; By RT-PCR(455bp) BCV was detected from 13 of the 75 sample of fecal swab from calves. The calves under 3 month showed the highest BCV detection rate.

• Korean Journal of Veterinary Service
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• v.19 no.1
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• pp.30-38
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• 1996

Enzyme-linked immunosorbent assay (ELISA) was developed to detect rotavirus antigen in fecal samples using VP6-specific monoclonal antibody(2B12). The ELISA for rotavirus antigen detection found to have specificity to all bovine and porcine rotaviruses tested but not to bovine viral diarrhea virus and bovine coronavirus. The ELISA appeared to have similar sensitivity and specificity compared to fluorescence antibody assay(FA) and electropherotyping (PAGE).

• Proceedings of the Microbiological Society of Korea Conference
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• 2005.05a
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• pp.227.2-227
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• 2005