Respiratory signs and blocd-tingeri diarrhea were obervl in cow of two dairy farms at Chia-Li, Tainan county in Felruary, 1982, Sixn oout of 44 cows, 36.4%, in K farm and 1(0% in S farm showel clinical signs of depression, anorexia, fever (39- 41.21 , severe diarrheam, reiwai milk godw±on, watery or purulent nasal discharge, coughing, and salivation. The course prolonged for about four days.
No virus was isolati from samples cultured on bovine en&yo kidney or bovine testis cell cultures. Sera samples resubjltoserologicaltests against six ldnds of viruses. The level of li magglutination-inlribition antibodies against bovine Coronavirus increased significantly in three weeks, i.e. , geonetric mean ofH I antibcdy of 1:26 (lOx—lEa<) at zero week, 1:250 (8Ox—128&x) at a week pcetinfection, 1:337 (8Ctx—1,28Ox) at2weeks Pland 1:230(1Ox—l, 280) at3 weeks PL Itwas concludedthattheinfection was caused by bovine Caonavinis. The sera samples were also pcxsitive against Rota virus (1(0% in HI test), P1-3 virus (1(0% in neutralization test), Adeno-7 type virus (3%), and BVD virus (10%), while were negative against IBR virus.
During the outheak of teli diesase, the daily temperature change in the dairly farm area was 9.3 -11.3 *, It seems that the big variation oftemperaturein a day was related to the outheak of the disease, bovine Coronavirus infection.