FIG 1.

M. hyopneumoniae DNA and antibody detection by day postinoculation (dpi) in a room housing 1,250 pigs in 46 pens (23 white rectangles by 2 columns) in study 2. Ten pigs in a centrally located pen (yellow rectangle) were intratracheally administered with M. hyopneumoniae (strain 232). Thereafter, one noninoculated pig per pen was sampled/tested at each time point. M. hyopneumoniae DNA and antibody-positive results from noninoculated pigs were represented by “+” for positive PCR in tracheal samples and by squares colored by one of each the three ELISAs (ELISA 1, SK108 Mhyo, BioChek, Berkshire, UK; ELISA 3, M. hyo Ab test, IDEXX Laboratories Inc., Westbrook, ME, USA; ELISA 5, Civtest Suis Mhyo, Laboratorios Hipra, S.A., Girona, Spain) for positive result in serum samples. Results were based on PCR tracheal samples (15 and 28 dpi) and blood samples (15, 28, 42, and 56 dpi) collected from one noninoculated pig at each time point. In the remaining pens, tracheal and blood samples were collected from one pig at 15, 24, 42, 56, 71, 85, and 98 dpi. Serum samples with suspect classification were assumed positive. NS, no sample collected.