Eight Years of Progeny-test Selection for Resistance and Susceptibility to Lymphomatosis

SINCE the first report of Asmundson and Biely (1932), which indicated that resistance to fowl paralysis is inherited, numerous studies on this subject have been conducted at various experiment stations. The emphasis in these studies has been placed on the importance of breeding selection in the control of this disease, now known in its various common manifestations as neural, visceral, or ocular lymphomatosis. Hutt, Cole, and Bruckner (1941) have recently reviewed the pertinent literature in this field. The purpose of this paper is to present data in extension of earlier reports (Taylor and Lerner, 1938; Taylor and DeOme, 1939) relating to the genetic nature of resistance to lymphomatosis, and also to introduce evidence concerning the fluctuations in the incidence of the disease from year to year under similar managemental conditions for the flock. Lymphomatosis particularly of the neural type, had been current in the Single Comb White Leghorn flock of . . .