Can you explain how mycoplasma synoviae in chickens spreads?

M. synovium: Infection is via the conjunctiva or upper respiratory tract with a long incubation period, 11-21 days following contact exposure. Transmission may be transovarian, or lateral via respiratory aerosols and direct contact. Survival of the infectious agent outside the bird is poor but fomite transmission between farms is important. Predisposing factors include stress and viral respiratory infection