Frecuencia de M. hyopneumoniae, M. hyorhinis y M. hyosynoviae en muestras nasales y de pulmón de cerdos con síntomas de neumonía enzoótica porcina

M. hyopneumoniae, M. hyorhinis and M. hyosynoviae are genetically related species of the genus Mycoplasma that affect pig production. The objective of this work was the isolation and identification by PCR of M. hyopneumoniae , M. hyorhinis and M. hyosynoviae from nasal swabs and lung samples of pigs from different regions of Mexico in order to determine the frequency of these species and to evaluate PCR as a diagnostic tool for PEP. Pigs aged 4 to 8 weeks with clinical diagnosis of PEP were included. Lung samples and nasal swabs were obtained for the isolation of the Mycoplasma in liquid Friis medium and identified by species-specific PCR based on the 16S rRNA subunit. Isolation was achieved in 37.11 % (36/97) of the samples. The three Mycoplasma species were identified in lung and nasal swab samples. Mycoplasma co-infection was identified in 27.77 % (10/36). The bacterial genera associated with Mycoplasma infections were E. coli , Bordetella , Enterobacter , SCN, Corynebacterium , Pasteurella , Streptococcus , Shigella and Klebsiella . Mixed infection was present in 26 nasal swabs (45.61 %) and absent in the lungs. It was concluded that the frequency of Mycoplasma on  production  farms  was higher  than  expected (40.27 %). It was also identified other Mycoplasma species involved in the development of PEP. Therefore, surveillance through isolation and molecular techniques can be of great help to breeding stock providers, as well as for removing Mycoplasma from pig farms.