Veterinary Microbiology, 31 ( 1992 ) 1 - 10 1 Elsevier Science Publishers B.V., Amsterdam Coronavirus infection in mink (Mustela vison ). Serological evidence of infection with a coronavirus related to transmissible gastroenteritis virus and porcine epidemic diarrhea virus P. Have a, V. Moving a, V. Svansson b, ,. Uttenthal c, B. Bloch b aState Veterinary Institute for Virus Research, Lindholm, DK-4 7 71 Kalvehave, Denmark bDepartment of Veterinary Microbiology, Royal Veterinary and Agricultural University, DK- 1870 Frederiksberg C., Denmark CDanish Furbreeders Association, DK-2600 Glostrup, Denmark (Accepted 18 September 1991 ) ABSTRACT Have, P., Moving, V., Svansson, V., Uttenthal, A. and Bloch, B., 1992. Coronavirus infection in mink (Mustela vison). Serological evidence of infection with a coronavirus related to transmissible gas- troenteritis virus and porcine epidemic diarrhea virus. Vet. Microbiol., 31: 1-10. Antibodies to a transmissible gastroenteritis virus (TGEV)-related coronavirus have been dem- onstrated in mink sera by indirect immunofluorescence, peroxidase-linked antibody assays and im- munoblotting. This is the first serological evidence of a specific coronavirus infection in mink. The putative mink coronavirus (MCV) seems to be widespread in the Danish mink population with a prevalence approaching 100%. Analysis by immunoblotting has shown that MCV is closely related to TGEV by the spike (S), matrix (M) and nucleoprotein (N) polypeptides. Furthermore, antibodies to MCV also cross-reacted with N and M polypeptides of porcine epidemic diarrhea virus (PEDV). Thus MCV may occupy an intermediate position between the TGEV group of coronaviruses and PEDV. The possibility that MCV may be associated with syndromes of acute enteritis in preweaning mink is discussed. INTRODUCTION Coronaviruses infect a number of mammalian and avian species and the mammalian viruses are usually placed in two major serological groups repre- sented by mouse hepatitis virus (MHV) and transmissible gastroenteritis vi- rus (TGEV) (Sturman and Holmes, 1983, Siddell et al., 1983). The MHV group includes bovine coronavirus (BCV), porcine hemagglutinating en- cephalomyelitis virus (HEV) and human coronavirus (HCV) OC-43. The TGEV group includes porcine respiratory coronavirus (PRCV) (Pensaert et 0378-1135/92/$05.00 1992 Elsevier Science Publishers B.V. All rights reserved. 2 p. HAVE ET AL. al., 1986, Sinchez et al., 1990), canine coronavirus (CCV), feline infectious peritonitis virus (FIPV) and feline enteric coronavirus (FECV). Mature vi- rions of coronaviridae contain three major structural proteins (Cavanagh et al., 1990) of which the spike (S) glycoprotein and transmembrane matrix (M) glycoprotein are glycosylated. The nucleoprotein (N) is associated with the positive-stranded RNA genome. Coronaviruses are responsible for var- ious disease manifestations in their host species, depending on virus tropism (e.g. pneumotropic, enterotropic or neurotropic viruses ). Porcine epidemic diarrhea coronavirus (PEDV) (Pensaert et al., 1981 ), causing a gastroenteritis similar to TGE in pigs, is as yet unclassified, al- though a slight serological relationship with FIPV has been demonstrated (Yaling et al., 1988 ). Until recently, no known cell culture system was avail- able for propagation of PEDV in vitro but this has now been accomplished using VERO cells and medium including proteases such as trypsin (Hofmann and Wyler, 1988 ). The apparent Mr values of PEDV structural proteins have been found to be 85 000-135 000K for the S protein, 58 000 for the N protein and 20 000-32000 for the M protein (Egberink et al., 1988 ). This serological study on mink coronavirus was initiated by our observa- tions in electron microscopy of coronavirus-like particles in stool samples from neonatal mink kits suffering from diarrhea. Specific coronavirus infections have so far not been described in mink but coronavirus-like particles in feces have recently been associated with epizootic catarrhal gastroenteritis in mink (Gorham et al., 1990). The present paper provides the first serological evi- dence for infection in mink with a coronavirus (here designated MCV) ser- ologically related to TGEV and PEDV. MATERIAL AND METHODS Viruses TGEV (Purdue strain) and PRCV (Danish isolate DK1/86, Have, 1991 ) were grown in a swine testicle (ST) cell line (McClurkin and Norman, 1966 ). CCV (strain 1-71 ) was grown in A-72 cells (ATCC CRL 1542 ). FIPV (strain DF2, ATCC VR-2004) and FECV (strain WSU 79-1683, ATCC VR 989) were grown in Crandell feline kidney (CRFK) cells. PEDV (strain 1/87 ) was kindly provided by Dr. S. Cartwright, Weybridge, as an intestinal passage of PEDV-infected colostrum-deprived newborn piglets. After a further two pas- sages in piglets the virus was adapted to grow in VERO cells by the method of Hofmann and Wyler (Hofmann and Wyler, 1988 ). Sera Four groups of mink sera were selected for evaluation of MCV antibodies: A, 71 mi