Developing Mitigation Strategies for Common Fish Culture Stressors

Molecular chaperones and their involvement with a phenomenon called cross-protection have captured the attention of many developing therapeutic approaches to animal health, including fish health.  We continue to examine this topic using channel catfish.  Heat treatments and other stimulants that induce production of the molecular chaperone, HSP70, lead to enhanced resistance to subsequent stress treatments in a wide variety of fish species.  Our recent experiments have evaluated the presence or absence of induced stress resistance in different ages of fish.  While our data illustrate that while we can elicit resistance to an ammonia challenge consistently in six month old fish we are less successful in producing the same level of protection in newly hatched catfish fry.  The interaction of fish developmental stage and rearing temperature likely play confounding roles in our observations to date.  Ideally, therapeutic approaches to mitigating aquaculture stressors should be consistent across life stage and environmental gradients and we will discuss our laboratory results in this context.