2003 Volume 56 Issue 12 Pages 793-797
A case of sheep-associated malignant catarrhal fever (SA-MCF) was observed in one Japanese Black cow on a beef ranch where cattle and sheep were kept together. The animal had pyrexia, anorexia, and a cough and died in 5 days. Histological investigation showed angiitis in the major organs of the dead animal. Ovine herpes virus-2 (OvHV-2) genes were detected in cells from these organs. None of the 25 other head of cattle kept with the affected one showed similar symptoms. Polymerase chain-reaction checks of peripheral-blood leucocytes (PBL) showed OvHV-2 genes in 10 out the 25. Successive checks made at 2-month intervals over 11 and 13 months detected OvHV-2 genes consistently in the PBL of 2 animals. This suggests that at least 10 head of cattle were subclincally affected by SA-MCF and that 2 head were persistently infected by OvHV-2 during the observation period.