Evaluation of the efficacy of a trivalent vaccine mixture against a triple challenge with Mycoplasma hyopneumoniae, PCV2, and PRRSV and the efficacy comparison of the respective monovalent vaccines against a single challenge

Oh, Taehwan; Park, Kee Hwan; Yang, Siyeon; Jeong, Jiwoon; Kang, Ikjae; Park, Changhoon; Chae, Chanhee

Currently, PRDC is one of the biggest health concerns to the Asian swine industry. The etiological agents associated with PRDC may vary between different geographic regions, but in Asia, Mycoplasma hyopneumoniae, porcine circovirus type 2 (PCV2), and porcine reproductive and respiratory syndrome virus (PRRSV) are the primary pathogens which cause the majority of the PRDC cases resulting in devastating economic losses [1] . Most Asian swine producers control PRDC by use of preventative vaccines rather than antibiotics. Combination vaccines are preferred in order to reduce pig stress and to decrease labor cost. A trivalent vaccine mixture (3FLEX, Boehringer Ingelheim Vetmedica, St. Joseph, Missouri, USA) against M. hyopneumoniae, PCV2, and PRRSV has been licensed in many Asian countries to control PRDC. However, there is concern from some swine producers that this trivalent vaccine mixture may be less effective compared to the respective monovalent vaccines currently available because of possible interferences among the mixed antigens. In this study, we decided to evaluate the efficacy of this trivalent vaccine mixture (3FLEX, Boehringer Ingelheim Vetmedica) against a triple challenge of M. hyopneumoniae, PCV2, and PRRSV and compare it to the efficacy of the respective monovalent vaccines. Clinical, immunological, microbiological, and pathological parameters were chosen for evaluation.