Discussion

Proliferative kidney disease, caused by the myxozoan parasite Tetracapsuloides bryosalmonae, is a major disease issue for farmed rainbow trout in the UK. The parasite is now recognised as a Cnidarian, and so the host-parasite interaction is relatively unique. Fish can become immune to the disease if they survive a first infection, and we have studied the immune responses elicited in both naive and re-exposed fish to shed light on this phenomenon. In addition, we have used transcriptomic approaches to study the parasite genes expressed in trout with a view to identify vaccine candidates. This talk will outline the results to date, indicating that a dysregulation of immunity occurs post-infection, and that host specific gene expression can be identified in the parasite.