Further Evidence of Hereditary Resistance and Susceptibility to Cecal Coccidiosis in Chickens

THE economic impact of disease resistance studies of animals has not rivaled that conducted with plants although numerous investigations concerning the role of inheritance of disease resistance in animals have been reported. Convenient reviews of the innate resistance of animals to various diseases have been written by Gowen (1937), Brandly and Waters (1942), and Hutt (1949). Certain of these studies have led to a better understanding of the host-pathogen-environment relationship, and others have shown that the Mendelian influence on disease resistance and susceptibility does occur in the form of various defense mechanisms. Although Lerner (1950) has written, “It would appear that breeding against susceptibility to diseases which are not endemic or which can be controlled by other means is not an efficient procedure, even when the possibility of reduction in disease incidence by selective breeding has been established,” such studies may be of value if for no other reason than …