对比差异 meaning in English

contrast difference

By morphologic examination , structure characteristics ^ biological property n serological tests and pathology characteristic study , this virus was identified as the medium virulence chicken . new castle disease virus ( ndv ) , whose pathology characteristics were appeared different from those of the standard virulence ndv . la sola vaccine could not give good protection against the infection of this virus isolate
用spf鸡胚在吉林省患病鸡群中分离到一株病毒，经病毒形态学、结构特征、生物学、血清学及致病性等试验研究，确定该病毒为鸡新城疫强毒，对lasota免疫鸡的致病性及其致死率与鸡新城疫标准强毒e _ 9f _ ( 48 )对比差异显著， lasota疫苗对该株病毒免疫保护效果不理想。