Bacteriological, serological, histological and immunohistochemical findings in laying hens with naturally acquired Salmonella enteritidis phage type 4 infection.

Salmonella enteritidis phage type 4 was isolated from the reproductive tract of 10 (27 per cent) of 37 laying hens from three small flocks with a naturally acquired infection. The rapid slide agglutination test with Salmonella pullorum-antigen was positive in 24 (64.9 per cent) of the 37 hens including the six hens in which the ovary was colonised and the 10 in which the oviduct was colonised. By immunohistochemical labelling S enteritidis was demonstrated in seven of eight culture-positive hens on the surface of and within the epithelial cells in the lumen and in the tuberine glands of the oviduct.