The Comparison of Aluminum Hydroxide and ISA70 Adjuvants for Induction of Humoral Response against Recombinant Pyolysin of Trueperellapyogenesin Sheep

This study was conducted to compare the efficacy of sheep humoral immune response induction of two commercial adjuvants used routinely in veterinary vaccines. Forty-eight (48) local native-bred lambs of 2 to 3 months old were chosen and divided into four groups; the treatment groups were immunized twice، two weeks apart، with 0. 2 mg of pyolysin toxoid in combination with aluminum hydroxide or ISA70 adjuvants by subcutaneous injection. The lambs in the control groups received the same sterile normal saline solution with equal amounts of aluminum hydroxide or ISA70 adjuvants at the same times. The blood samples were taken in days 14، 28، and 98 from all of the lambs after the first immunization، and their sera were measured for anti-pyolysin antibodies by hemolytic neutralization assay. According to the results، the mean titers of anti-pyolysin antibodies in immunized lambs with pyolysin toxoid and ISA70 adjuvants were significantly higher than the mean titers of antibodies in the group that received toxoid with aluminum hydroxide adjuvant (P<0. 05). It appears that the use of ISA70 adjuvant in vaccines is more efficacious than hydroxide aluminum adjuvant.