Molecular detection and isolation of Mycoplasma conjunctivae from goats with infectious keratoconjunctivitis in Sichuan province, southwest China

Infectious keratoconjunctivitis (IKC) is a common contagious ocular disease in ruminants worldwide characterized with keratitis and conjunctivitis and, in severe cases, blindness. Recently two outbreaks of infectious keratoconjunctivitis (IKC) occurred in goats in Sichuan Province, China. To identify the causative agent responsible for these outbreaks, ocular swabs were then taken from 40 goats with IKC and 22 goats without IKC for isolation and molecular detection of mycoplasma. Mycoplasma conjunctivae-specific nested-PCR was 85.0% positive among samples from goats with IKC and 40.9% positive from goats without IKC. Nine PCR products were sequenced and showed that there was 99.6-100% sequence homology among themselves and 99.6-100% with NCBI M. conjunctivae DNA sequences from strain Goat 655, HRC/583 and HRC/581T. A total of 6 strains of M. conjunctivae were also successfully isolated. In this study, we present conclusive evidence of the presence of M. conjunctivae in Sichuan Province, southwest China. This is the first report of M. conjunctivae infection outbreaks in small ruminants in mainland of China and will be helpful for vaccine development and control of IKC in goats in this region.