The effect of temperature and water quality on antibody response to Aeromonas salmonicida in sunshine bass (Morone chrysops × Morone saxatilis)

The kinetics of the antibody response to Aeromonas salmonicida were determined in sunshine bass (hybrid striped bass: female Morone chrysops × male Morone saxatilis) acclimated to 10, 18, 24, 29°C, and to 0.15 mg l−1 un-ionized ammonia and 200 mg l−1 nitrate levels. Temperature and water quality factors affected the immune response of sunshine bass. Temperatures of 10°C and 18°C decreased the magnitude and delayed the time of the antibody response to A. salmonicida. The antibody response was not affected at 29°C, which is above the optimal temperature for sunshine bass. Elevated un-ionized ammonia concentrations of 0.15 mg l−1 also did not affect the antibody response. Elevated nitrate levels of 200 mg l−1, however, decreased the antibody response to the same extent as 18°C water.