Temperature and Photoperiod Regulation of B-Cell Mediated Adaptive Immunity in Rainbow Trout (Oncorhynchus mykiss): Implications for Aquaculture and Climate Change
LIB-314
Erin Bromage
508.999.8218
ebromage@umassd.edu
Advisor: Dr. Erin Bromage
Committee members: Dr. Genevieve Kozak, Dr. Katrina Velle, Dr. Michael Sheriff
Abstract:
Seasonal changes in temperature and photoperiod shape immunity across vertebrates, yet their interactive effects on adaptive immune responses in ectotherms remain poorly understood. In teleost fish, temperature is a well-established regulator of adaptive immunity, but the contribution of photoperiod—and its interaction with temperature—remains unclear. This knowledge gap has important implications for predicting immune responses under climate change and optimizing environmental conditions in aquaculture.
Using a fully factorial experimental design, rainbow trout (Oncorhynchus mykiss) were acclimated to two temperatures (10°C and 15°C) and three photoperiods (8L:16D, 12L:12D, and 16L:8D) before immunization with a defined antigen. Temperature emerged as the primary driver of adaptive immunity, with fish held at 15°C exhibiting faster and stronger B-cell responses, higher serum IgM concentrations, and greater antigen-specific antibody titers than fish maintained at 10°C. In contrast, photoperiod exerted more modest and context-dependent effects, with short-day conditions enhancing specific antibody production primarily in immunized fish.