Large-Quantity Production of Chicken Embryo Tracheal Organ Cultures and Use in Virus and Mycoplasma Studies

Chicken tracheal organ cultures were made from embryos which were 19 to 20 days old. Transversely cut rings of trachea were placed in screw-capped tissue-culture tubes with Eagle's-N-2-hydroxyethylpiperazine-N′-2-ethanesulfonic acid (HEPES) medium and incubated in roller drums. The method had advantages over other organ culture systems in that these cultures were prepared in numbers similar to conventional tissue cultures, ciliary activity was quickly and accurately evaluated, and contamination occurred less frequently than with organ cultures in petri dishes. Ciliary activity persisted for at least 1 month when the medium was changed at 5-to 7-day intervals and for 10 to 15 days without a change. Infectious bronchitis virus stopped ciliary movement, and this effect was used as a basis for titrating the virus and for determining the neutralizing capacity of immune mouse ascitic fluid. Twenty-four Mycoplasmastrains were tested. Organisms of 17 strains, both avian and mammalian, multiplied in the organ cultures, and 7 strains, belonging to the species M. gallisepticumand M. mycoidesvar. capri, inhibited ciliary activity.