Aquaculture Africa 2024

November 19 - 22, 2024

Hammamet, Tunisia

Add To Calendar 21/11/2024 12:00:0021/11/2024 12:20:00Africa/CairoAquaculture Africa 2024INTROGRESSIVE HYBRIDIZATION LEVELS AMONG TILAPIINES DRIVEN BY TRANSLOCATIONS ACROSS AFRICACesar The World Aquaculture Societyjohnc@was.orgfalseDD/MM/YYYYanrl65yqlzh3g1q0dme13067

INTROGRESSIVE HYBRIDIZATION LEVELS AMONG TILAPIINES DRIVEN BY TRANSLOCATIONS ACROSS AFRICA

Gerald Kwikiriza1,2,3, Thapasya Vijayan1, Faith Atukwatse2, Juliet Kigongo Nattabi2 Genanaw Tesfaye1,4, Darlington Besa1, Papius Dias Tibihika1,5, Manuel Curto1,6, John Kariuki1, Harald Meimberg1

1Institute of Integrative Nature Conservation Research, Department for Integrative Biology and Biodiversity Research (DIBB), BOKU University, Gregor-Mendel-Straße 33, Vienna 1180, Austria

2Department of Zoology, Entomology and Fisheries Sciences, Makerere University, P.O. Box, 7062, Kampala, Uganda

3Kachwekano Zonal Agricultural Research and Development Institute, National Agricultural Research Organization, P.O. Box 421, Kabale, Uganda

4EIAR - National Fisheries and Other Aquatic Life Research Center, P.O. Box 64, Sebeta, Ethiopia

5Aquaculture Research and Development Centre Kajjansi (ARDC), National Fisheries Resources Research Institute (NaFIRRI), National Agricultural Research Organization, P.O. Box 530, Kampala, Uganda

6CIBIO—Research Center in Biodiversity and Genetic Resources, University of Porto, 4485-661 Vairão, Portugal

Gerald Kwikiriza

Institute of Integrative Nature Conservation Research, Department for Integrative Biology and Biodiversity Research (DIBB), BOKU University, Gregor-Mendel-Straße 33, Vienna 1180, Austria

Email: gerald.kwikiriza@boku.ac.at / gkwikiriza2@gmail.com

 



The taxonomical complexities consistently challenge the continued use of the Tilapia as an aquaculture candidate. These complexities have been fueled by fish translocations leading to hybridization and admixture which complicate taxonomy and sound units for management and sustainability. Amidst these challenges, less information is available that is useful to fully understand the African Tilapiines at the continental level. This study characterized 10 tilapiine species collected from different water bodies in Africa, using microsatellites and mitochondrial markers. Three and two lineages of Oreochromis niloticus and Oreochromis esculentus respectively are defined. Among the 50 populations, comparisons among the East African water bodies showed extremely lower genetic differentiation. For example, Kyoga and Victoria (0.03), and Mulehe and Kayumbu (0.19). Multivariate analysis like principal coordinate analysis (PCoA) showed higher levels of admixtures between the natural and translocated populations.  The high level of introgression was recorded between Oreochromis machrochir and Oreochromis mweruensis. These results provide valuable insights for biodiversity conservation, fisheries management, and the development of genetically sustainable Tilapia breeding programs, ensuring the long-term viability of these species in their natural habitats and aquaculture settings.