الفهرس 
1. IntroductionOnly 14 pages are availabe for public view
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Abstract
Salmonella infection is an important cause of mortality and morbidity in cattle, subclinically infected cattle are frequently found which constitute an important reservoir for human infections. Combined salmonella and bovine viral diarrhoea virus (BVDV) infection was more severe than salmonella infection alone due to the immunosuppressive action of BVDV. So, this work aimed for preparation of a combined inactivated S. Typhimurium, S. Dublin and BVDV vaccine for control and prophylaxis of adult cattle and calves against salmonellosis and BVDV infections. The prepared combined inactivated S. Typhimurium, S. Dublin and BVDV vaccine was evaluated for sterility, safety and potency. The immunogenicity of the combined inactivated S. Typhimurium, S. Dublin and BVDV vaccine was investigated in calves in comparison with bivalent inactivated S. Typhimurium – S. Dublin vaccine and monovalent inactivated BVDV vaccine with and without inoculation of levamisole.
It was found that combined inactivated S. Typhimurium, S. Dublin and BVDV vaccine free from aerobic, anaerobic bacterial contamination, Mycoplasma and fungal contaminants. Also, the vaccine was safe for mice and cattle. For potency tests the combined inactivated S. Typhimurium, S. Dublin and BVDV vaccine gave best results that the protection percentage was (90%) when virulent S. Typhimurium 2656V was used in the challenge test but was (80%) when virulent S. Dublin 2656V was used in the challenge test while for bivalent inactivated S. Typhimurium – S. Dublin vaccine the protection percentage was (80%) wen virulent S. Typhimurium 2656V was used in the challenge test but was (70%) when virulent S. Dublin 2656V was used in the challenge test. For the vaccine immunogenicity in calves the combined inactivated S. Typhimurium, S. Dublin and BVDV vaccine gave highest antibody titres but the immune response was better in calves inoculated with levamisole, that in calves group immunized with combined inactivated S. Typhimurium, S. Dublin and BVDV vaccine and inoculated with levamisole, the maximum serum agglutinating antibody titre was 1/5120, maximum ELISA antibody titre was 9.51 while maximum serum neutralizing antibody titre was 512.
But in calves group immunized with combined inactivated S. Typhimurium, S. Dublin and BVDV vaccine without inoculation of levamisole maximum serum agglutinating antibody titres was 1/2560, maximum ELISA antibody titre was 9.37 and maximum serum neutralizing antibody titre was 256. For calves group vaccinated with bivalent inactivated S. Typhimurium, S. Dublin vaccine it was found that maximum serum agglutinating antibody titre was 1/1280 and maximum ELISA antibody titre 8.30.
It was concluded that, from data obtained in this study, the combined inactivated S. Typhimurium, S. Dublin and BVDV vaccine was recommended for control and prophylaxis of calves and adult cattle against salmonellosis and BVDV infection with avoidance of the risk of shedding, abortion and reversion to virulence.