Swine conjunctivitis outbreaks associated with .

Conjunctivitis is an uncommon finding in commercial swine herds, and the etiology of the disease is rarely studied. We investigated cases of conjunctivitis in 3 wean-to-finish swine farms. Eye swabs and tissues were obtained from clinically affected pigs (8-22 wk of age), from unaffected pigs in contact with affected pen-mates, and from age-matched pigs from an unaffected herd. Real-time PCR (rtPCR) testing for demonstrated consistent detection and high bacterial load in samples from affected herds (clinically affected animals and non-clinical pen-mates). Ct values in affected pigs were 18.9-25.3; values were 36.4-38.6 in unaffected pigs from unaffected herds. Additionally, was identified within inflamed palpebral conjunctivae by in situ hybridization. The association of rtPCR and in situ detection of , along with the lack of detection of other potential pathogens and noninfectious causes, suggests the involvement of in the etiology and pathogenesis of the reported swine conjunctivitis.