The Susceptibility of Different Breeds of Chickens to Experimental Salmonella Gallinarum Infection

LAMBERT (1932a) showed that it was possible by selective breeding to develop strains of chicks that varied greatly in regard to resistance to Salmonella gallinarum infection (see also Gowen, 1948; and Bell, 1949). Lambert (1932b) also tested the resistance of unselected chicks of different breeds to the intraperitoneal injection of Salmonella gallinarum when seven days old. Only slight differences were noted between the breeds, the mortality rates being very high, varying from 79.7 to 94.4 percent. During recent studies at the Poultry Research Station to find a suitable breed for investigating the effect of chemotherapeutic agents on experimental fowl typhoid, considerable variation was noted between different breeds when they were infected orally at 8 weeks of age (Smith 1955a,b). In view of this, it was decided to extend these studies, the results of which are contained in this paper. It will be apparent that these studies were not planned on …