There was a significant difference in the survival times of fish fed the equivalent number of eggs cured with mixtures containing a high and low concentration of sodium sulfite. Our intention was to determine whether the number of eggs needed to cause mortality was within the range of what a wild juvenile might consume. Thus, we did not attempt to quantify the actual dose of sodium sulfite in the mixes that were administered. We initially attempted to quantify the number of eggs required to cause mortality by Z-VAD-FMK feeding individual fish a known number of eggs. However, the experiment was unsuccessful as Chinook generally do not feed well when held alone in a tank. Interestingly though, we noted a rapid decrease in ‘‘appetite’’ when the individually housed fish were fed cured eggs. This effect was reversed by switching to uncured eggs. This is consistent with the observations of Rankin showing learned aversion to food that is toxic and suggests that the juvenile salmon may learn to avoid such foods following an initial exposure. However, it is not clear whether this would apply in situations where individuals are competing for food as we did not observe a decrease in ‘‘appetite’’ Regorafenib when fish were housed in groups. Interestingly, we did not observe any mortality in fish that were fed cure 4 for 23 d. We maintained daily records of feeding behavior and this group consistently scored lowest for appetite. In addition, a large number of uneaten eggs were removed from the tanks at the end of the experiment. Taken together, these observations suggest that, when given a choice, few fish consumed the eggs cured with cure 4 during the feeding trials. We suspect this explains the low level of mortality as we did observe high levels of mortality when cure 4 was administered directly into the gut using a syringe. We conclude that exposure via the gut alone is sufficient to cause death in juvenile salmonids. Exposure via the gills did not cause any mortality over a 10 d period. We made no attempt to determine the cause of death though the available literature suggests a number of possible pathways, including toxicity to the central nervous system, disruption of enzyme activity, or oxidative damage. Changes in enzyme activity are unlikely to explain the rapid nature of mortality we observed in several animals following ingestion of cured eggs.