Fig. 3.

The overall weighted and individual histological scores for the trachea, nares and tracheal cilia for each dog grouped according to treatment and day of necropsy (two dogs at each necropsy time point). The overall “weighted” score puts a larger emphasis on histological changes in the lower respiratory which are likely to be more clinically significant than histological changes in the upper respiratory tract are not uncommon and unless marked, are considered part of the normal defences of the upper respiratory tract. The hatched and solid bars represent each dog per necropsy time point. The table shows the average overall weighted score for each treatment group.