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All three Mycoplasma species are inhabitants of the respiratory tract of pigs. M. hyopneumoniae contributes to porcine respiratory disease complex (PRDC) when other bacterial and viral agents are present. M. hyosynoviae invades joints contributing to lameness and arthritis. M. hyorhinis can cause polyserositis and is associated with chronic arthritis. The objective of this study was to evaluate by cross-sectional sampling the prevalence of these three Mycoplasma species using various sample collection and testing methods.
Vaccinated pigs from eleven, three site production flows with historically high late finishing mortality were sampled at 6-7 weeks, 10-11 weeks, and 15-16 weeks of age, representing mid-nursery, early finisher and mid finisher phases of production. For each age group sampled four pens were selected for a single oral fluid collection. In each pen, five pigs were selected for blood collection and deep pharyngeal swab.
All samples for M. hyorhinis were positive by oral fluids and > 99% were positive by pharyngeal swab (n = 132). All oral fluid samples for M. hyopneumoniae were negative and < 2% were positive by pharyngeal swab. For M. hyosynoviae, 62.9% of oral fluid samples and 18.9% of pharyngeal swabs were positive. Of the blood samples, 57% tested positive for M. hyopneumoniae by Tween 20 ELISA (n = 656). These results indicated that oral fluids may be a more sensitive way to test for M. hyosynoviae and M. hyorhinis compared to pharyngeal swabs as more samples were found to be positive with oral fluids or the CT values of oral fluids were lower than the pharyngeal swabs although the values for the two methods trended to- gether. ELISA was a better method for detecting positive results for M. hyopneumoniae exposure compared to oral fluids or pharyngeal swabs. M. hyorhinis was highly prevalent across all sampling ages while M. hyosynoviae and M. hyopneumoniae exhibited increased prevalence with increasing pig age.
In conclusion, oral fluids PCR was a more sensitive test for detecting animals positive for M. hyorhinis and M. hyosynoviae, while Tween 20 ELISA should be used for M. hyopneumoniae.
Samuel P. Copeland, Mary A. Battrell, Jeremy S. Pittman, Rebecca C. Robbins. Exploring the prevalence of M. hyorinis, M. hyosynoviae, and M. hyopneumoniae, across various age groups using various sampling techniques. Proceedings 2013 AASV Annual Meeting.
