Scanning electron microscopy was used in the study of the post-vaccinal respiratory reaction of the tracheal epithelium of ducks (Anas platyrhynchos) immunized against Newcastle disease. Forty-eight ducks were distributed into four groups: T1 - control birds (non-vaccinated); T2 - birds vaccinated with Ulster 2C strain; t3 - birds vaccinated with B1 strain; and t4 - birds vaccinated with LaSota strain. Regardless the experimental group, birds did not show detectable clinical signs of post-vaccinal respiratory reaction. Scanning electron microscopy showed that birds vaccinated with B1 and LaSota strains developed epithelial sloughing of the trachea, whereas those vaccinated with Ulster 2C strain did not develop this change, showing intact tracheal epithelium, similar to the control group. However, the birds vaccinated with B1 strain showed evidences of regeneration of tracheal epithelium 21 days post-vaccination, which did not happen with the ducks vaccinated with LaSota strain.
duck; scanning electron microscopy; trachea epithelium; respiratory pos-vaccinal reaction; Newcastle disease virus
