Focusing on pathobiology and protective strategies against protozoan and metazoan parasites of fish, this book reviews the latest research on important parasites: those that cause financial hardships to the aquaculture industry, have been introduced to new geographical regions through transportation of infected fish, are pathogenic to groups of finfish and detrimental to production, are highly adaptable and not host-specific with worldwide distributions, and that may serve as disease models for studies on other pathogens. It also highlights gaps in the knowledge to help direct future research.

As the human population increases and nations become more industrialized, the habitat and water quality required for the survival of fish continues to decline. In addition to these environmental factors, fish populations are directly or potentially affected by harvesting, enhancement programs and introgression with hatchery-propagated or transgenic fish. To our knowledge no other scientific meeting has been assembled to consider the breadth of the problem, to review the technology that is presently available for the preservation of the germ plasm of salmonid stocks and to identify the scientific advances that are required to overcome the problems. Because many salmonids have spawning grounds within the confines of a specific region or county but will spend a large portion of their life cycle within the territorial waters of other countries or in the open ocean, the preservation of unique genes or gene pools in these animals requires international cooperation. This scientific meeting has provided a forum in which to discuss the problems, evaluate the present methods or technology for addressing the problems and suggest new directions or innovations that need to be implemented. During this meeting we limited our discussion to salmonid fishes. However, the general conclusions about the factors that affect the population dynamics of fish stocks and the technical aspects concerning the preservation of germ plasm will be applicable to other fish species.