Reproductive strategies of parasitic flatworms (Platyhelminthes, Monogenea): the impact on parasite management in aquaculture

Disease management is crucial for the global growth of aquaculture. Parasitic monogeneans present a high risk for finfish aquaculture industries and have been associated with reduced growth, morbidity and mortality. Monogeneans are extremely fecund and exhibit short generation times which can result in exponential population growth. Information on the reproductive biology of specific monogenean species can enable strategically timed treatments to break parasite life cycles. However, the diversity of reproductive strategies (oviparity, viviparity and self-fertilisation) presents considerable barriers in disease management. In addition, environmental conditions such as seasons, water temperature and salinity also influence parasite life cycles, including generation time, fecundity, egg embryonated period and age at sexual maturity. This review examines the diversity of reproductive strategies exhibited by monogenean parasites and the influence of environmental parameters on parasite life cycles. Various parasite management strategies including mechanical, biological and chemical treatments are evaluated