COMPARISON OF RESISTANCE OF VARIOUS POULTRY LINES TO INFECTION BY SALMONELLA-ENTERITIDIS

A study was undertaken to determine the susceptibility or resistance o f 9 outbred experimental or commercial poultry lines to Salmonella ent eritidis PT4. Young chicks were inoculated either intramuscularly or o rally just after hatching. After intramuscular challenge the lines cou ld be divided into susceptible lines (LD 50% less-than-or-equal-to 10( 2) Salmonella per animal), intermediate lines (LD 50% about 10(4) Salm onella) and resistant lines (LD 50% > 10(5) Salmonella). The results o btained after oral challenge confirmed these 3 groups for both mortali ty rates and the probability of the presence of salmonellae in the spl een and liver. There was no difference between lines concerning caecal carriage.