Africa has vast potential for aquaculture growth, however, the translocation of African cichlid fishes for aquaculture has resulted in the co-introduction of some of their parasites. G yrodactylids attachment to fish causes epidermal damage and fin erosion resulting in reduced swimming capacity and increased mortali ty. High parasite burdens cause physiological and histological disturbances that can induce osmoregulatory failure. The objectives of this study are; to conduct first-level taxonomy of the parasite Gyrodactylus based on morphological and molecular characterization; to observe the population structure in parasites between different farming systems, bio-geographical regions, or drainage areas representing different populations, and to measure the impact of the disease caused by these parasites on productivity, survival (or mortality) and sustainability of t ilapia aquaculture in South Africa at different levels of production. Specimens of Gyrodactylus will be collected from culture d and natural populations of O. Mossambicus , O. Niloticus, and C. Rendalii from different bio-ge ographical regions representing different populations. Each sample of fish will be fixed and stored in 95% ethanol until examination. Type material deposited in national collectio ns will also be included in the study. Parasitic indices such as the mean intensity, prevalence, and a bundance will be determined and calculated. Findings from this study will provide information on the major clusters of Gyrodactylids parasitizing the tilapia population. The extent of morphological and molecular variation between parasite specimens and population will be obse rved. The prevalence, intensity, and epidemiological impact of the Gyrodactylids in Tilapia Aqua culture will be determined and potential control measures identified.
Keywords: Gyrodactylus, Genetics, Epidemiology, Aquaculture, South Africa.