[Horseradish peroxidase (HRP) in intravenous administration is not present in the bursal lumen after interruption of the connection between the bursa and cloaca].

A surgical technique, which we recently described, was used to interrupt the anatomical connection between the bursa of Fabricius and the cloaca. This was done in order to ascertain whether H.R.P. e.v. injected into the wing vein might reach the bursal lumen through the follicle associated epithelial cells, as suggested by Bockman and Stevens, or to establish whether, on the contrary, the way used by H.R.P. to gain access to the bursal lumen might be another:e.v. injected H.R.P. may be excreted by the chicken kidneys, as we demonstrated, then it may pass into the bursal lumen through the cloaca thanks to the duct connecting the two organs. In the present paper we show that the interruption of this connection prevents e.v. injected H.R.P. from gaining access to the bursal lumen.