. 2020 Apr 20;88(5):e00053-20. doi: 10.1128/IAI.00053-20

TABLE 1.

Mean tracheal mucosal thicknesses of the upper, middle, and lower trachea of vaccinated and unvaccinated birds after challenge

Group	No. of birds	Treatment (CCU/0.03 ml)^a	Challenge (10^6.5 CCU/ml)^a	Mean tracheal mucosal thickness ± SD (μm)^b
Group	No. of birds	Treatment (CCU/0.03 ml)^a	Challenge (10^6.5 CCU/ml)^a	Upper	Middle	Lower
Vaccinated and challenged	20	ts-304 (10^6.0)	Ap3AS	88.5 ± 27.8^a	64.9 ± 29.8^a	58.0 ± 27.3^a
Challenged only	20	Merial diluent only	Ap3AS	212.9 ± 88.8^b	177.6 ± 99.6^b	181.0 ± 93.0^b

CCU, color changing units.

Values marked with the same lowercase superscript letter were not significantly different (P > 0.05).