VACCINATION OF CALVES WITH LIVE MODIFIED AND LIVE VIRULENT STRAIN OF SALMONELLA TYPHIMURIUM

Sixteen normal colostrum-fed -Friesian and Holestein-Friesian X Angus crossbred calves, ranging in age from 2 to 7 weeks were divided into 4 vaccinated groups 1 nonvaccinated (control) group. Group I consisted of calves orally twice at a two week interval with small doses organisms ( 104 thar1l05 live virulent Salmonella gghimurium, strain 108-11). ll 1011 (modified typhimurium, SL 3261 ). [[1 vaccinatedlivitwice than 105 typhimurigg, IV 3 which 1M atv/o with109 modified 108-11(SL 1479). V served as controls. One after the final vaccine close all challenge exposedwith 1.5x viable typliimurium, 108-11. The results vaccination different preparation indicated that designated 1479 complete, nonreverting blocks aromatic biosynthesis may beappropriate for protecting domestic animals against infection.