Figure 1

Experimental design and sample collection scheme. *Eight pigs were inoculated with inactivated Mycoplasma hyopneumoniae, while eight pigs were inoculated with the viable bacterium. Two pigs were humanely euthanized at every time point (one pig per experimental group). Black diamonds indicate ante-mortem tracheal secretions sample collection. Black triangle indicates blood sample collection. Black circles indicate post-mortem sample collection at necropsy, including tracheal scrapings, bronchial secretions, bronchoalveolar lavage fluid, thoracic lymph nodes and spleen. Macroscopic and microscopic lung lesion assessment and grading was performed in all euthanized pigs.