Veterinary Microbiology, 32 (1992) 267-271 Elsevier Science Publishers B.V., Amsterdam
267
Isolation of Fukuoka virus, a member of the Kern Canyon serogroup viruses of the family Rhabdoviridae, from cattle M. Noda a, Y. Inaba b, M. Banjo a and M. Kubo c aKabe Livestock Hygine Service Center, Hiroshima, Japan bDepartment of Veterinary Epizootiology, College of Agriculture and VeterinaryMedicine, Nihon University, Fufisawa, Japan CNational Institute of Animal Health, Tsukuba, Japan (Accepted 30 January 1992)
ABSTRACT Noda, M., Inaba, Y., Banjo, M. and Kubo, M., 1992. Isolation of Fukuoka virus, a member of the Kern Canyon serogroup viruses of the family Rhabdoviridae, from cattle. Vet. Microbiol., 32: 267271. Four virus strains with identical antigenicproperties were isolated from blood samples of 4 sentinel calves having a fever and leukopenea in cultures of HmLu-1 cells derived from baby hamster lung. The virus was identified as Fukuoka virus, classified as a member of the Kern Canyon serogroup viruses of the family Rhabdoviridae, on the basis of its antigenic properties.
INTRODUCTION
Fukuoka virus, belonging to the family Rhabdoviridae, was firstly isolated from the biting midges, Culicoides punctatus and Culex tritaeniorhynchus, collected at cattle stock pens in Fukuoka, Kyushu Island, Japan (Kaneko et al., 1986; 1987). Subsequently the virus was classified as a member of the Kern Canyon serogroup viruses of the family Rhabdoviridae by Calisher et al. (1989). In the present study, we isolated Fukuoka virus from the blood of calves with a fever and leukopenia in Hiroshima Prefecture, Japan. This paper describes the isolation of Fukuoka virus and preliminary characterization of the virus. Correspondence to: Dr. Y. Inaba, Department of Veterinary Epizootiology, College of Agriculture and Veterinary Medicine, Nihon University, Fujisawa 252, Kanagawa, Japan.
0378-1135/92/$05.00 © 1992 Elsevier Science Publishers B.V. All rights reserved.
268
N. NODA ET AI..
MATERIALS AND METHODS
In 1986, 1987 and 1988, 108, 125 and 60 sentinel calves, respectively, were distributed in various parts of Hiroshima Prefecture located in the western part of Honshu Island, Japan. Heparinized blood samples were collected periodically once a month over the period from June to November in every year. The blood was centrifuged at 1500 g for 10 min. The sedimented blood cells were washed 3 times with phosphate-buffered saline (PBS) (pH 7.2), and the final pellet was suspended in PBS to equal the original volume of the blood and stored at 80°C until use for virus isolation. For virus isolation four culture tubes of HmLu-1 cells, derived from baby hamster lung, were used for each blood sample. Culture fluids of the primary inoculated culture at the 7th day of inoculation were subinoculated twice into freshly prepared cultures of HmLu-1 cells. Isolation of virus was indicated by the appearance of a cytopathic effect (CPE) in the cultures. Strain YHL of bovine ephemeral fever (Inaba et al., 1968 ), strain Fuk-11 of Fukuoka virus (kaneko et al., 1986), in the Kern Canyon serogroup viruses of the family Rhabdoviridae (Calisher et al., 1989), strain No. 2 of Ibaraki virus (Omori et al., 1969), strain OBE- 1 of Akabane virus (Kurogi et al., 1976 ) and strain K-47 of Chuzan virus in the Palyam serogroup of the genus Orbivirus of the family of Reoviridae (Miura et al., 1988) were used. These strains were passaged in HmLu-1 cells. Antisera against the isolated virus strain 62-48-21, and Fukuoka, bovine ephemeral fever, Ibaraki, Akabane and Chuzan viruses were prepared in guinea pigs weighing 300-400 g by the method described in the previous papers (Kurogi et al., 1989; Miura et al., 1988). Neutralization (NT) tests were performed by the serum dilution method, using tube cultures of HmLu-1 cells. Serial 2-fold dilutions in 0.5 ml volumes of the serum inactivated at 56 °C for 30 min were mixed with an equal volume containing 200 TCIDs0 of virus per 0.1 ml. The virus-serum mixtures were incubated at 37°C for 60 min before inoculation of 0.1-ml volumes into two tube cultures per serum dilution. The inoculated cultures were incubated in a roller drum at 37°C for 7 days. The NT antibody titer was expressed as the reciprocal of the highest serum dilution inhibiting CPE in at least one of the two tubes. RESULTS
Four strains of a virus were isolated from blood samples obtained from the sentinel calves; one from calf No. 18 on 9 September 1986, two from calf No. 21 on 13 October and from calf No. 2 on 9 November 1987, and one from calf No. 2 on 12 July 1988. The clinical signs of these calves were slight fever, 41.2°C to 42.0°C, and leukopenia, 4.5 to 5.0× 103 per mm 3 at the time of
ISOLATION OF FUKUOKA VIRUS
269
TABLE 1
Neutralizing antibodies against the isolated virus, 62-48-21, and some other arboviruses; bovine ephemeral fever (BEF), Ibaraki (IBA), Akabane (AKA) and Chuzan (CHU) viruses, in sentinel cattle in Hiroshima Prefecture Cattle herd
Cattle No.
Virus isolation
Antibody titers against Isolated virus
BEF
IBA
AKA
CHU
a~
bI
a
b
a
b
a
b
a
b
61-38
18 19 20 21 22
+ -
267
Isolation of Fukuoka virus, a member of the Kern Canyon serogroup viruses of the family Rhabdoviridae, from cattle M. Noda a, Y. Inaba b, M. Banjo a and M. Kubo c aKabe Livestock Hygine Service Center, Hiroshima, Japan bDepartment of Veterinary Epizootiology, College of Agriculture and VeterinaryMedicine, Nihon University, Fufisawa, Japan CNational Institute of Animal Health, Tsukuba, Japan (Accepted 30 January 1992)
ABSTRACT Noda, M., Inaba, Y., Banjo, M. and Kubo, M., 1992. Isolation of Fukuoka virus, a member of the Kern Canyon serogroup viruses of the family Rhabdoviridae, from cattle. Vet. Microbiol., 32: 267271. Four virus strains with identical antigenicproperties were isolated from blood samples of 4 sentinel calves having a fever and leukopenea in cultures of HmLu-1 cells derived from baby hamster lung. The virus was identified as Fukuoka virus, classified as a member of the Kern Canyon serogroup viruses of the family Rhabdoviridae, on the basis of its antigenic properties.
INTRODUCTION
Fukuoka virus, belonging to the family Rhabdoviridae, was firstly isolated from the biting midges, Culicoides punctatus and Culex tritaeniorhynchus, collected at cattle stock pens in Fukuoka, Kyushu Island, Japan (Kaneko et al., 1986; 1987). Subsequently the virus was classified as a member of the Kern Canyon serogroup viruses of the family Rhabdoviridae by Calisher et al. (1989). In the present study, we isolated Fukuoka virus from the blood of calves with a fever and leukopenia in Hiroshima Prefecture, Japan. This paper describes the isolation of Fukuoka virus and preliminary characterization of the virus. Correspondence to: Dr. Y. Inaba, Department of Veterinary Epizootiology, College of Agriculture and Veterinary Medicine, Nihon University, Fujisawa 252, Kanagawa, Japan.
0378-1135/92/$05.00 © 1992 Elsevier Science Publishers B.V. All rights reserved.
268
N. NODA ET AI..
MATERIALS AND METHODS
In 1986, 1987 and 1988, 108, 125 and 60 sentinel calves, respectively, were distributed in various parts of Hiroshima Prefecture located in the western part of Honshu Island, Japan. Heparinized blood samples were collected periodically once a month over the period from June to November in every year. The blood was centrifuged at 1500 g for 10 min. The sedimented blood cells were washed 3 times with phosphate-buffered saline (PBS) (pH 7.2), and the final pellet was suspended in PBS to equal the original volume of the blood and stored at 80°C until use for virus isolation. For virus isolation four culture tubes of HmLu-1 cells, derived from baby hamster lung, were used for each blood sample. Culture fluids of the primary inoculated culture at the 7th day of inoculation were subinoculated twice into freshly prepared cultures of HmLu-1 cells. Isolation of virus was indicated by the appearance of a cytopathic effect (CPE) in the cultures. Strain YHL of bovine ephemeral fever (Inaba et al., 1968 ), strain Fuk-11 of Fukuoka virus (kaneko et al., 1986), in the Kern Canyon serogroup viruses of the family Rhabdoviridae (Calisher et al., 1989), strain No. 2 of Ibaraki virus (Omori et al., 1969), strain OBE- 1 of Akabane virus (Kurogi et al., 1976 ) and strain K-47 of Chuzan virus in the Palyam serogroup of the genus Orbivirus of the family of Reoviridae (Miura et al., 1988) were used. These strains were passaged in HmLu-1 cells. Antisera against the isolated virus strain 62-48-21, and Fukuoka, bovine ephemeral fever, Ibaraki, Akabane and Chuzan viruses were prepared in guinea pigs weighing 300-400 g by the method described in the previous papers (Kurogi et al., 1989; Miura et al., 1988). Neutralization (NT) tests were performed by the serum dilution method, using tube cultures of HmLu-1 cells. Serial 2-fold dilutions in 0.5 ml volumes of the serum inactivated at 56 °C for 30 min were mixed with an equal volume containing 200 TCIDs0 of virus per 0.1 ml. The virus-serum mixtures were incubated at 37°C for 60 min before inoculation of 0.1-ml volumes into two tube cultures per serum dilution. The inoculated cultures were incubated in a roller drum at 37°C for 7 days. The NT antibody titer was expressed as the reciprocal of the highest serum dilution inhibiting CPE in at least one of the two tubes. RESULTS
Four strains of a virus were isolated from blood samples obtained from the sentinel calves; one from calf No. 18 on 9 September 1986, two from calf No. 21 on 13 October and from calf No. 2 on 9 November 1987, and one from calf No. 2 on 12 July 1988. The clinical signs of these calves were slight fever, 41.2°C to 42.0°C, and leukopenia, 4.5 to 5.0× 103 per mm 3 at the time of
ISOLATION OF FUKUOKA VIRUS
269
TABLE 1
Neutralizing antibodies against the isolated virus, 62-48-21, and some other arboviruses; bovine ephemeral fever (BEF), Ibaraki (IBA), Akabane (AKA) and Chuzan (CHU) viruses, in sentinel cattle in Hiroshima Prefecture Cattle herd
Cattle No.
Virus isolation
Antibody titers against Isolated virus
BEF
IBA
AKA
CHU
a~
bI
a
b
a
b
a
b
a
b
61-38
18 19 20 21 22
+ -
