[Potential manifestation of fowl typhoid in chicks fed Salmonella gallinarum-contaminated feed].

The possibility was checked to infect young birds with fowl typhoid through feeding them with S. gallinarum--contaminated forage. The three test groups of birds were kept on the floor of one and same premise, and a fourth group was kept separately in isolation. The feed offered to the first and second test group was contaminated at the rate of 5.10(8) and 1.2.10(8) microbial cells, respectively. With the first group, where feed contamination was at the rate of 6.10(6) S. gallinarum cells per bird, mortality rate ran as high as 61 per cent, 53 per cent of the total number of birds dying of typhoid septicaemia. With the second group, where feed contamination was 1.2.10(6) S. gallinarum cells per bird the total rate of mortality was 34 per cent, 32 per cent of the birds dying of typhoid septicaemia. With the third group, exposed to air-borne infection and offered Salmonella-free feed only, 8 per cent of the birds died of typhoid. It was found that the manifestation and the intensity of the epizootic process were in direct dependence on the microbial number, and that air played a part in transmitting S. gallinarum to young birds raised on the floor.