Swine respiratory disease is generally considered a multifactorial problem caused by a combination of viral and bacteria......

本试验结果证明,仔猪实验感染支气管败血波氏杆菌(Bb)后再接触感染产毒素多杀巴氏杆菌(Pm);或自然感染Bb后再实验感染产毒素Pm;或......