The 6 th Asian Pig Veterinary Society Congress Ho Chi Minh City, Vietnam September 23-25, 2013 PO158 SEROLOGICAL ASSESSMENT OF CO-INFECTIONS WITH PRIMARY AND SECONDARY RESPIRATORY PATHOGENS OF SWINE Ewelina Czyżewska, Arkadiusz Dors, Małgorzata Pomorska-Mól, Krzysztof Kwit, Zygmunt Pejsak Department of Swine Diseases, National Veterinary Research Institute, Pulawy, Poland z.pejsak@piwet.pulawy.pl Introduction Porcine Respiratory Disease Complex (PRDC) is an important polymicrobial syndrome worldwide 1 . There are a variety of viral and bacterial, primary and secondary pathogens commonly associated with PRDC including porcine reproductive and respiratory syndrome virus (PRRSV), swine influenza virus (SIV), porcine circovirus type 2 (PCV2), porcine respiratory coronavirus (PRCV), Mycoplasma hyopneumoniae (Mhp), Actinobacillus pleuropneumoniae (App), Pasteurella multocida (Pm), Haemophilus parasuis (HPS), Streptococcus suis (S. suis) 2,3 . These infections can lead to significant economic losses. It is important to determine which agents are involved regionally in the etiology of PRDC 1 . The aim of this study was to determine existence and frequency of co-infection with primary and secondary respiratory pathogens associated with PRDC in Polish swine herds. Materials and Methods The study was conducted in 68 farrow-to-finish pig herds located in different provinces of Poland. All herds had a history of respiratory disorders. On each herd, 36- 48 serum samples were randomly collected from different age groups of pigs: 4-5, 6-8, 9-12, 13-16, 17- 20, 20-24 weeks of life. Serum samples were examined for the presence of antibodies against; PCV2 (Ingezim PCV2-ELISA), PRRSV (in house ELISA), Mhp (M. hyo: Idexx ELISA), SIV (H1N1, H1N2, H3N2 suptypes) (haemagglutination inhibition test) and App (App: IDVet ELISA). Results In all 68 herds antibodies against PCV2 were detected. Regarding to SIV and PRRSV percent of positive herds ranged from 92.6% to 39.6%, respectively. A 94.7 % of investigated herds were seropositive to App and 87% to Mhp. Furthermore, antibodies to H1N1, H1N2 and H3N2 were detected in 87%, 51%, 74% herds, respectively. The number of herds with respective number of pathogens isolated/detected is presented in Table 1. Co- infections with various infectious agents are presented in Table 2. Table 1. Number of herds according to number of detected pathogens Table 2. Simultaneous presence of antibodies against several infectious agents involved in PRDC in Polish swine herds (n=68) Discussion and Conclusions This study shows that polymicrobial respiratory diseases are still very important problem in swine industry. All investigated herds had mixed infection with at least two infectious agents. It means in Poland, similar to other countries, there is circulation of at least several agents involved in the PRDC 4,5 . PCV2 was involved in all combination of mixed infection, and it emphasizes ubiquity character of this virus. It is worth to notice that more than 94% of herds were infected with at least four different important swine pathogens. Moreover, in recent years, SIV seems to play an important role in the development of PRDC. More than 89% of tested herds were infected with one, two or three subtypes of SIV. In summary, for implementation of proper treatment, prophylaxis and management strategies, not single but polymicrobial infection with several pathogens should be taken into account. These practices should minimalism losses in pig production and improve its efficiency. Acknowledgements This work was supported by grant from Ministry of Science and Higher Education, No. N N308 571740. Literature cited 1. Paladino E. S. et al. 2012. Proc 22 th IPVS Congress, 763. 2. Oprriesnig T. et al. 2011. Anim Health Res Rev 12: 133-148. 3. Thacker E. et al. 2001. Vet Clin North Am Food Anim Pract 17: 551-565. 4. Fraile L. et al. 2010. Vet J 184: 326-333. 5. Meyns T. et al. 2011. Vet J 187: 388-392. No. of pathogens detected No. of herds 1 0 2 3 3 1 4 38 5 26 Presence of antibodies against No. (%) of positive herds PCV2+SIV+App+Mhp+PRRSV 26 (38.23) PCV2+SIV+App+Mhp 33 (48.52) PCV2+SIV+Mhp+PRRSV 1 (1.47) PCV2+Mhp+App+PRRSV 4 (5.88) PCV2+App+Mhp 1 (1.47) PCV2+SIV 2 (2.94) PCV2+App 1 (1.47)