Comparative efficacy of four vaccines against Salmonella virchow in chicks in India.

The efficacy of four vaccines in preventing Salmonella virchow infection in poultry was assessed by determining survivors after challenge, bacteriological status of tissues and excretion through stool and eggs following artificial infection in vaccinated and control birds. The study indicated that formol killed oil-adjuvant vaccine conferred the highest degree of immunity followed by gel and Freund's complete adjuvant vaccines.