Clinically and etho1ogical1y, two lapinid HC vaccine viruses, the LPOChinese (LEG) and Chinese (Chinese) strains, cause no abnormal reflons in pigs, but induced similar fever respnses, the enlargement of lymph ncdes (LN), rticularly mesentery UT, and h sthological changes in the ham, such as neuronal satellitosis, neuronophagia and perivascular cuffings in rabbit. Both lapinized HC viruses had a similar viral distribution petan in rabbit and pigs. Lymphat tsi wre mainly infected with the viruses. The result indicated that these two lapinized HC vaccine viruses had identical ethogenicity and viral distribution in rabbits and pigs. Therefore, it may suggest that these two viruses have the same origin.