Table-1.

Postmortem lesion scores in the experimental groups after challenge with the ORT.

Groups	Thoracic air sacs					Abdominal air sacs					Lungs
	NO	Score 0	Score 1	Score 2	% MPS	NO	Score 0	Score 1	Score 2	% MPS	NO	Score 0	Score 1	Score 2	% MPS
V1	18	15	3	0	8.3	18	16	2	0	2.8	18	16	2	0	5.6
V2	18	16	2	0	5.6	18	18	0	0	0	18	17	1	0	2.8
C1	18	3	2	13	77.8	18	4	1	13	75	18	8	3	7	42.7
C2	18	18	0	0	0	18	18	0	0	0	18	18	0	0	0

MPS=Maximum possible score, NO=Number of birds, V₁=Razi ORT vaccine, V₂=Intervet ORT vaccine, C₁=Positive control, C₂=Negative control