Arch Virol (2001) 146: 2401–2419
Cross-protection studies between respiratory and calf
diarrhea and winter dysentery coronavirus strains in calves
and RT-PCR and nested PCR for their detection
, M. Hasoksuz
, P. R. Nielsen, K.-O. Chang,
, and L. J. Saif
Food Animal Health Research Program, Department of Veterinary Preventive Medicine,
Ohio Agricultural Research and Development Center, The Ohio State University,
Wooster, Ohio, U.S.A.
Accepted January 17, 2001
Summary. A 1-step RT-PCR assay, targeting a 730 bp fragment of the nucleo-
capsid (N) gene of bovine coronavirus (BCV), and a nested PCR assay, targeting
a 407 bp fragment of the N gene, were developed to detect BCV in nasal swab
and fecal samples of calves experimentally exposed to BCV. Both 1-step RT-PCR
and nested PCR recognized cell culture passaged isolates of 10 bovine respiratory
coronavirus (BRCV), 5 calf diarrhea (CD) and 8 winter dysentery (WD) strains
of BCV, but not transmissible gastroenteritis coronavirus or bovine rotavirus. The
sensitivity of the 1-step RT-PCR and nested PCR was compared to that of an
antigen-capture ELISA. The lowest detection limit of the 1-step RT-PCR and
nested PCR as determined by using tenfold serial dilutions of the BRCV 255 and
440 strains in BCV negative nasal swab suspensions from preexposure gnotobi-
otic calves was 2 × 10
and 2 × 10
/0.1 ml for each strain, respectively.
The lowest detection limit of the antigen-capture ELISA as determined by using
the same serially diluted samples was 1 × 10
/0.1 ml for each strain.
Therefore, the 1-step RT-PCR and nested PCR assays were 50 and 5000 times,
respectively more sensitive than the antigen-capture ELISA to detect BRCV
in nasal swab suspensions. To investigate in vivo cross-protection between the
BRCV and CDor WDstrains of BCV and to detect nasal and fecal shedding
Present address: College of Veterinary Medicine, Chonnam National University,
Kwangju 500-757, South Korea.
Permanent address: Istanbul University, Veterinary Faculty, Department of Micro-
biology, Avcilar, 34851, Istanbul, Turkey.
Present address: EISO, Bacterial Zoonoses Branch, Centers of Disease Control and
Prevention’s National Center for Infectious Diseases, Division, Fort Collins, CO, U.S.A.