Blackhead in Turkeys: A New Conception of the Nature of the Disease and Suggestions for New Methods in Prophylactic Feeding

Abstract

Notwithstanding the inestimable advantages that have followed the conception of the germ-theory of disease, the energetic application of this theory in an a priori sense has sometimes served to retard rather than to advance the progress of events toward the solution of the etiological problems involved.This has been especially true of blackhead in turkeys. Since the time when the parasitic bodies were first discovered by Theobald Smith in the cecal and liver tissues, the conception of their specificity and of the marked communicability of the disease through their agency has been held by all investigators, with a perfectly natural tenacity. We have been fearful of infecting other stock from turkeys sick with the disease; we have proclaimed against the mixing of ordinary hens, bearers of infection with the young poults; we have dreaded the assured possibility of “yard infection.” In our experimental work we have attempted by all possible …