I am a Research Scientist in Freshwater Aquaculture. Currently am involved in research in alternative protein sources for sustainable production of fish feeds, the application of probiotics aquaculture and improvement of quality of African Catfish and Nile tilapia seed through hybridization of different strains and selective breeding. I have 12 years of experience in aquaculture research and have published 14 books and books chapters, 32 peer reviewed papers in SCI-indexed journals, and 26 conference proceedings. I have collaborated with various institutions in aquaculture research managed by international and regional organizations such as LIDC, ICIPE, UK-RI, VLIR-UOS, BBSRC,STFC, KCSAP, WIOMSA, ASARECA, VicRes-IUCEA and KAPAP with funding from DfID, European Union (EU), SIDA and World Bank. I have been the National coordinator of the Seed quality assessment in the country for both private and public fish hatcheries where my responsibilities are monitoring and evaluation of the performance of the hatcheries, coordinating the development of Tilapia and Catfish seed standards and authentication of new hatcheries; which has led to the supply of seed to meet the demand of fish seed across the country. I am a member of the National technical team responsible for the development of the Manual of Standard Operating Procedure for Fish Inspection and Quality Assurance for Fish Business Operators in Kenya, East Africa Community (EAC) technical committee for fish seed standards and certification guidelines and a member of the African Union-International Bureau of Animal Resources (AU-IBAR) Taskforce on African ornamental fisheries. I have carried out 15 research projects including;- Using Black Soldier Fly Larvae as Sustainable Protein Source for Fish; Addressing livestock derived antimicrobial resistance in Nairobi river basin, Enhancing omega 3 fatty acids in farmed fish; Probiotics applications in aquaculture; Selective breeding of Nile tilapia; Strategic framework for Aquaculture Education in Kenya; Commercialization of fish feed production; Enhancing productivity and Competitiveness of Aquaculture; Fish Farming Enterprise Productivity Program; Aquaculture production through sustainable technologies and market linkages. I have been a resource person in training of fish farmers, Hatchery managers, processors, traders, students and government extension officers in Good aquaculture practices, Sanitary and phytosanitary requirements in Aquaculture, Ornamental fishery, Seed production and hatchery management, Aquaculture entrepreneurship, Aquaculture economics, Aquaculture nutrition, Fish health management and general aquaculture management. I have previously served as a research assistant at CARE Kenya an international NGO dealing in small holder livelihood projects.
Publications: Research gate link: https://www.researchgate.net/profile/Mary_Opiyo
Google Scholar link: https://scholar.google.com/citations?user=rhnT9H0AAAAJ&hl=en
2015 - 2020: PhD, Fisheries Science, Kenyatta University, Kenya
2007-2010: MSc. Fisheries and Aquatic Sciences (Aquaculture), Moi University, Kenya
2003-2007: BSc. Fisheries and Aquatic Sciences, Moi University (Kenya)
- Abwao, J., Jung’a, J., Barasa, J.E., Kyule, D., Opiyo, M., Awuor, J.F., Ogello, E., Munguti J.M. &.Keya, G. A (2021). Selective breeding of Nile tilapia, Oreochromis niloticus: A strategy for increased genetic diversity and sustainable development of aquaculture in Kenya, Journal of Applied Aquaculture, https://doi.org/10.1080/10454438.2021.1958728
- Chepkirui, M., Orina, P.S., Opiyo, , Muendo, P., Mbogo, K., Omondi, R. (2021). Fatty acids composition of Nile tilapia (Oreochromis niloticus) fingerlings fed diets containing different levels of water spinach (Ipomoea aquatica), Journal of Agriculture and Food Research, 5, September 2021,100156. https://doi.org/10.1016/j.jafr.2021.100156.
- Awuor, F.J., Opiyo, M.A., Obiero, K.O., Munguti, J.M., Abwao, , Nyonje, B.M., Nevejan, N. and Van Stappen, G. (2021). Aquaculture Extension Service in Kenya: Farmers and Extension Officers, Journal of Agricultural Extension and Rural Development, ISSN: 2141-2170 13(1) 14-22. https://academicjournals.org/journal/JAERD/article-full-text-pdf/56AB84765877
- Kyule, D.N., Fonda, J.A., Ochiewo, J., Munguti, M.J., Obiero, K.O., Ogello, E.O., Opiyo, M.A., Abwao, J. and Kendi, J. (2020) Perceived consumer preferences of fisheries products retailed in Kenyan markets Bioscience Research, 17(4): 2486-2496.
- Opiyo, M.A., Obiero, K.O., Abwao, J., Awuor, F.J., Kyule, D. and Munguti, J. (2020). Comparative growth performance of genetically male, sex-reversed and mixed-sex Nile tilapia (Oreochromis niloticus) reared in earthen ponds in Sagana, Kenya. Aquaculture Studies, 21(1): 23-30 http://www.aquast.org/uploads/pdf_507.pdf
- Holeh, G.M., Appanteng, P., Opiyo, M.A., Park, J., Brown, C.L. (2020). Effects of intermittent feeding regimes on growth performance and economic benefits of Amur catfish (Silurus asotus). Aquatic Research, 3(3), 167-176.
- Opiyo, M. A., Jumbe J., Ngugi C.C., Charo-Karisa H. (2019). Different levels of probiotics affect growth, survival and body composition of Nile tilapia (Oreochromis niloticus) cultured in low input ponds. Scientific African 4 (July 2019) e00103 https://doi.org/10.1016/j.sciaf.2019.e00103
- Opiyo, M. A., Jumbe, J., Ngugi, C. C. and Charo-Karisa, H. (2019). Dietary administration of probiotics modulates non-specific immunity and gut microbiota of Nile tilapia (Oreochromis niloticus) cultured in low input ponds. International Journal of Veterinary Science and Medicine 7 (1): 1-9 https://doi.org/10.1080/23144599.2019.1624299
- Fonda, J. A., Obiero, K., Munguti, J., Oginga, J.O., Kyule, D., Opiyo, M. A., Oduor-Odote, P., Yongo, E., Owiti, H. and Ochiewo, J. (2019). Market linkages and distribution channels of cultured, captured and imported fish in Kenya. Aquaculture studies, Volume 19 Issue 1, http://doi.org/10.4194/2618-6381-v19_1_06
- Opiyo, M.A., Marijani, E., Muendo, P., Odede, R., Leschen, W. and Charo-Karisa, H. (2018). A review of aquaculture production and health management practices of farmed fish in Kenya. International Journal of Veterinary Science and Medicine. https://doi.org/10.1016/j.ijvsm.2018.07.001
- Orina, P.S., Charo-Karisa, H., Munguti, J.M., Boera, P., Abwao, J., Kyule, D., Opiyo M. A., Marcial H. and Rasowo, O. (2018). ) A Comparative Study of Labeo victorianus (Bouelenger, 1901) and Oreochromis niloticus (Linnaeus, 1758) in Polyculture Systems. Lakes & Reservoirs: Research and Management 23 (1): 56-62. https://doi.org/10.1111/lre.12202
- Nyonje, B.M., Opiyo, M. A., Orina, P. S., Abwao, J., Wainaina, M. and Charo-Karisa, H. (2018): Current status of freshwater fish hatcheries, broodstock management and fingerling production in the Kenya aquaculture sector. Livestock Research for Rural Development. Volume 30, Article #6. Retrieved January 9, 2018. http://www.lrrd.org/lrrd30/1/mary30006.html
- Opiyo, M.A. Orina, P. and Charo-Karisa, H. (2017) Fecundity, Growth Parameters and Survival Rate of Three African Catfish (Clarias gariepinus) Strains under Hatchery Conditions. Journal of Aquaculture Engineering and Fisheries Research 3(2): 75-81. E-ISSN 2149-0236. https://doi.org/10.3153/JAEFR17010
- Opiyo, M.A., Orina, P., Kyule, D., Munguti, J. M. Nyonje, B.M. and Charo-Karisa, H. (2016) Growth performance and survival of three African Catfish (Clarias gariepinus, Burchell 1882) strains reared in hapas in Kenya. Bulletin of Animal Health and Production in Africa Special Edition 2016 - Fisheries and Aquaculture Resources 64 (2): 31 – 39. ISSN 0378 – 9721. au-ibar.org/component/jdownloads/finish/14/2969
- Kyule, D. Opiyo, M.A. Ogello E., Obiero, K. Maranga, , Orina, P., Charo-Karisa, H. and Munguti, J. (2016). Determination of Fish Value Added Product- Preferences Among the Residents of Wote Town, Makueni County, Kenya . Bulletin of Animal Health and Production in Africa Special Edition 2016 - Fisheries and Aquaculture Resources 64 (2): 69 – 78. ISSN 0378 – 9721. www.au-ibar.org/component/jdownloads/finish/14/2969
- Opiyo, M. A., Mugo, J. B., Kyule, D. and Okemwa, G. (2016). Overview of Ornamental Fish Production in Kenya: Current status, Opportunities and Challenges. Bulletin of Animal Health and Production in Africa Special Edition 2016 - Fisheries and Aquaculture Resources, 64 (2): 193 – 200. ISSN 0378 – 9721. au-ibar.org/component/jdownloads/finish/14/2969
- Oluoch-Otiego, J., Oyoo-Okoth, E., Kipkorir, K.G.K.,.Chemoiwa., E.J., Ngugi, C.C., Simiyu, G., Omutange, E.S., Ngure, V. and Opiyo M.A. (2016). PCBs in fish and their cestode parasites in Lake Victoria. Environmental Monitoring and Assessment, 188:1-11. https://doi.org/10.1007/s10661-016-5483-0.
- Githukia, C. M., Kembenya, E. M. and Opiyo, M. A. (2016.) Anaesthetic Effects of Sodium Bicarbonate at Different Concentrations on African catfish (Clarias gariepinus) Juveniles. Journal of Aquaculture Engineering and Fisheries Research. 2(3): 151-158. ISSN 2149-0236. https://doi.org/10.3153/JAEFR16017
- Orina, P. S, Rasowo, J. O., Opiyo, M. A., Boera, P., Abwao, J. Charo-Karisa, (2014). Optimization of Seed and Broodstock Transport Densities for Improved Survival of survival of African carp (Labeo victorianus, Boulenger, 1901). International Journal of Chemical Studies, 2(2): 34-42. ISSN: 2321-4902. http://www.chemijournal.com/archives/2014/vol2issue2/PartA/4.1.pdf
- Opiyo, M.A. Munguti, J. M. Ogello, E.O., Charo-Karisa, H. (2014). Growth response, survival and profitability of Nile tilapia (Oreochromis niloticus) fed at different feeding frequencies in fertilized earthen ponds. International Journal of Science and Research (IJSR) 3 (9): 893-898. https://www.ijsr.net/archive/v3i9/U0VQMTQyMjE=.pdf
- Opiyo, M.A., Ngugi, C. C. and Rasowo, J. (2014). Combined effects of stocking density and background colour on growth performance and survival of Nile tilapia (Oreochromis niloticus, L.) fry reared in aquaria. Journal of FisheriesScience.com 8(3): 228-237. https://doi.org/10.3153/jfscom.201429
- Munguti, J.M., Musa, S., Orina, P.S., Kyule, D.N., Opiyo, M. A. Charo-Karisa, H. and Ogello, E.O. (2014). An overview of current status of Kenyan fish feed industry and feed management practices, challenges and opportunities. International Journal of Fisheries and Aquatic Studies 1(6): 128-137. ISSN: 2347-5129. http://www.fisheriesjournal.com/vol1issue6/Pdf/145.1.pdf
- Orina P.S., Munguti M., Opiyo, M.A., Charo-Karisa, H. (2014). Optimization of Seed and Broodstock Transport Densities for Improved Survival of Cultured Nile Tilapia (Oreochromis niloticus, L. 1758). International Journal of Fisheries and Aquatic Studies 2014; 1(5): 157-161. ISSN: 2347-5129. www.fisheriesjournal.com/archives/2014/vol1issue5/PartC/116.pdf
- Kyule, D., Opiyo, M.A., Yongo, , Obiero, K., Munguti J. and Charo-Karisa H. (2014). Fish product development and market trials of fish and fish products in Kenya: a case study of Kirinyaga and Meru Counties. Livestock Research for Rural Development 26 (6) Retrieved June 25, 2014, from http://www.lrrd.org/lrrd26/6/kyul26108.htm
- Obiero, K., Opiyo, M.A., Munguti, M.J., Orina, P.S., Kyule, D., Yongo, E., Githukia, C.M. and Charo-Karisa, H. (2014). Consumer preference and marketing of farmed Nile Tilapia (Oreochromis niloticus) and African Catfish (Clarias gariepinus) in Kenya: Case Study of Kirinyaga and Vihiga Counties. International Journal of Fisheries and Aquatic studies 1(5): 67-76. ISSN: 2347-5129. http://www.fisheriesjournal.com/vol1issue5/pdf/79.1.pdf
- Opiyo M.A., Githukia, C.M., Munguti J.M., and Charo-Karisa, H. (2014) Growth performance, carcass composition and profitability of Nile tilapia (Oreochromis niloticus ) fed commercial and on-farm formulated fish feed in earthen ponds. International Journal of Fisheries and Aquatic Studies, 1(5): 12-17. ISSN: 2347-5129. http://www.fisheriesjournal.com/vol1issue5/pdf/91.1.pdf
- Charo-Karisa, H., Opiyo, M.A., Munguti, J.M., Marijani, E. and Nzayisenga, L. (2013). Cost benefits analysis and growth effects of pelleted and unpelleted on-farm feeds on African catfish (Clarias gariepinus Burchell, 1822) in earthen ponds. Journal of Food, Agriculture, Nutrition and Development (AJFAND). Volume 13 No. 4: 8019-8033.September 2013. ISSN NO 16845374.
- Opiyo M.A., Charo-Karisa, H. and Ogello, E.O. (2013). Effectiveness of Sodium Bicarbonate as an Anaesthetic for different sizes of Nile tilapia (Oreochromis niloticus, 1758) Juveniles. International Journal of Aquatic Science (IJAS), Vol 4 No.2 14-22. ISSN: 2008-8019. http://www.journal-aquaticscience.com/2013%20(2)/Opiyo%20et%20al%20(2013)_2.pdf
- Mugo-Bundi, J., Oyoo-Okoth, E., Ngugi C.C., Manguya-Lusega, D., Chepkirui-Boit, V., Opiyo, M.A (2013). Utilization of Caridina nilotica, (Roux) meal as a protein source in feeds for Nile tilapia (Oreochromis niloticus). Aquaculture Research 46 (2): 346-357. https://doi.org/10.1111/are.12181
- Ogello, E., Omondi, R., Opiyo, M.A., Charo-Karisa, H., Munguti, J. and Aura, C.M., (2012). Survival and avoidance response of the freshwater gastropod Melanoides tuberculatus (Muller) to different concentrations of tobacco waste. Aquaculture Research 43:1571-1576. https://doi.org/10.1111/j.1365-2109.2011.02962.x
- Munguti J, Charo-Karisa H, Opiyo M.A, Ogello E.O, Marijani E, Nzayisenga, L and D. Liti (2012). Nutritive value and availability of commonly used feed ingredients for farmed Nile tilapia (Oreochromis niloticus L.) and African catfish (Clarias gariepinus, Burchell) in Kenya, Rwanda and Tanzania. African Journal of Food, Agriculture, Nutrition and Development (AJFAND). Volume 12 No. 3 May 2012. ISSN NO 16845374. https://www.ajol.info/index.php/ajfand/article/view/77095
- Ogello E.O. and Opiyo, M. A. (2011). A review of the African Catfish Production in Kenya: Opportunities and Challenges. Samaki News 4 (1):18-20. Department of fisheries, Nairobi, Kenya. https://www.researchgate.net/publication/267636008
BOOKS AND BOOK CHAPTERS
- Munguti J., Obiero, K., Orina, P., Mirera D., Kyule D., Mwaluma J., Opiyo M., Musa S., Ochiewo J., Njiru, J., Ogello, E. and Hagiwara. A. (Eds) (2021). State of Aquaculture Report 2021: Towards Nutrition Sensitive Fish Food Systems. Kenya Marine and Fisheries Research Institute, Mombasa, Kenya 190 pp.
- Orina, P., Kembenya, E., Opiyo, M.A., Wainaina, M., Ondiba, R., Abwao, J., Nyabeta, J., and Mwaluma, J. (2021). Fish Seed Sector: Genetic Breeding and Reproduction Technologies. In: Munguti et al., (Eds). State of Aquaculture in Kenya 2020: Towards Nutrition -Sensitive Fish Food Systems; Chapter 5: Pages 89–102. Kenya Marine and Fisheries Research Institute, Mombasa, Kenya
- Opiyo, M.A., Mziri, V., Musa, S., Kyule, D., Hinzano, S., Wainaina, M., Magondu, E., Werimo, K. and Ombwa, V. (2021). Fish disease management and biosecurity systems. In: Munguti et al., (Eds). State of Aquaculture in Kenya 2021: Towards Nutrition -Sensitive Fish Food Systems; Chapter 7: Pages 113–142. Kenya Marine and Fisheries Research Institute, Mombasa, Kenya
- Mirera, D., Nyonje, B., Opiyo, M.A, Obiero K., Awuor, FJ., Holeh, G., Kendi J. and Okechi, J. (2021). Aquaculture Research and Training in Kenya. In: Munguti et al., (Eds). State of Aquaculture in Kenya 2020: Towards Nutrition -Sensitive Fish Food Systems; Chapter 8: Pages 143–152. Kenya Marine and Fisheries Research Institute, Mombasa, Kenya
- Munguti, J.M., Obiero K., Kyule D, Orina, P S, Githukia C.M, Opiyo M.A, Fonda J.A, Elijah E, Ondiba R., Abwao J, Musa S, and Njiru J. (2019) Training of Trainers (ToT) manual for aquaculture value chain, Master Trainers’ Manual, Kenya Climate Smart Agriculture Project (KCSAP) Secretariat, KALRO Headquarters, Nairobi.
- Musa, S., Opiyo, M.A., Obiero, K.O., Ogello, E.O., Githukia, C.M., Ombwa, V., Kembenya, E., Boera, P., Okechi, J. (2017). Status of Freshwater Aquaculture in Kenya. In: Munguti et al. (eds.), State of Aquaculture in Kenya, Chapter 2, pp 10-24, Laxpress Services, Nairobi, Kenya.
- Orina, P.S. Kyule, D., Opiyo, M.A., Awuor, F. J. and Munguti J. M. (2017) Post Harvest Management, Value Addition and Marketing In: Munguti et al. (eds.), State of Aquaculture in Kenya, Chapter 5, pp 49-53, Laxpress Services, Nairobi, Kenya.
- Opiyo, M.A., Charo-Karisa, H., Obiero, K., Munguti, J.M., Orina, P.S., Ogello, E.O., Nyoro, J., Kyule, D.N., Nyonje, B. and Omollo, B.O. (2017). Overview of Good Aquaculture Practices in Kenya. Kenya Marine and Fisheries Research Institute (KMFRI), 34pp.
- Opiyo, A., Charo-Karisa, H., Nyonje, B., Omolo, B., Orina, P., Wainaina, M., Obiero, K., Munguti, J. (2017). Good Aquaculture Practices in Seed Production in Kenya: Volume 1. Tilapia and Catfish. Kenya Literature Bureau, Nairobi, Kenya. 60pp.
- Kyule-Muendo, D., Munguti, J.M., Opiyo, M.A., Obiero, O., Githukia, C.M., Orina, P.S., Njiru, J.M., Charo-Karisa, H. (2017). Fish Recipe Book, Volume 1. Kenya Literature Bureau, Nairobi, Kenya. 45pp.
- Obungu L., Mungai D., Nyandat, B. Opiyo, M.A. (2016). Fish farmers Training Manual: Sanitary and Phytosanitary Requirements and Technical Barriers to Trade, Government Printers, Nairobi.
- Obungu L., Mungai D., Nyandat, B. Opiyo, M.A. (2015). Manual of Standard Operating Procedures for Fish Inspection and Quality Assurance for Fish Business operators in Kenya. Government Printers, Nairobi.
- Obungu L., Mungai D., Nyandat, B. Opiyo, M.A. (2015). Fish quality assurance guidelines for fish business operations in Kenya
- Charo-Karisa, H., Munguti, J., Ouma, H., Masai, M.D., Opiyo, M.A. Okechi J.K. and Orina S. P. (2011). A fish farmer’s Manual: For beginners, Students and hatchery managers, KMFRI, River brooks Communication Network, Nairobi, 99pp
- 2021-2022: STFC PROJECT. Developing a data-driven communication platform for improving farmed fish distribution in Kenya (10,000 GBP). Principle Investigator
- 2021- 2022: MASMA-WIOMSA PROJECT. Optimizing Artemia Production Technology for Sustainable Aquaculture Development (APTSAD), Food Security and Economic Growth for the East African Coastal Communities Funding, USD 298,294. Co - Principle Investigator
- 2020-2021: KENYA CLIMATE SMART AGRICULTURE PROJECT (KCSAP)-WORLD BANK. Use of Locally Available Aquatic Macrophytes as Sustainable Ingredients for Fish Feeds for Rural Aquaculture Funding 4,406,500. Principle Investigator
- 2020-2021: GLOBAL CHALLENGE RESEARCH FUND, UK RESEARCH & INNOVATION Addressing Livestock-derived Antimicrobial pollution in the Nairobi River in Kenya. Funding, KES. 2,497,300 Co-Principle Investigator
- 2019-2021: CLIMATE SMART AGRICULTURAL PRODUCTIVITY PROJECT (CS-APP)-EU Leveraging on aquaculture technologies to enhance productivity, resilience and adaptation to climate change Funding, KES 8,671,408 Researcher
- 2019-2021: BIOINNOVATE AFRICA PROGRAMME PHASE II. Using Black Soldier Fly Larvae as an environmentally sustainable source, of affordable protein for Chicken and Fish Feed Funding, $ 666,656. Co-Principle Investigator
- 2017-2021: VLIR-UOS. Building a Strategic Framework for Aquaculture Education in Kenya., Funding €299, 874. Project Coordinator
- 2016: VLIR-UOS. Short Training Initiative (STI): Solving the bottleneck: improved practices for larval production of freshwater fish in East Africa. Funding, KES 2,500,000. Project Coordinator
- 2016-2019: Newton Fund Global Research Partnership (GRP) in Aquaculture. Evaluating Costs and Benefits of Prophylactic Health Products and Novel Alternatives on Smallholder Aquaculture Farmers in Asia and Africa (IMAQulate).. Funding £ Sterling 100,000.
- 2016-2019: Newton Fund Global Research Partnership (GRP) in Aquaculture. Development of alternative sustainable fish feeds to promote human health using novel non-conventional indigenous ingredients (SNIPH).Funding £ Sterling 347,790.
- 2011-2014: World Bank -Kenya Agricultural Productivity and Agribusiness Project (KAPAP). Commercializing aquaculture production through sustainable technologies and market linkages. Lead researcher on fish seed quality improvement. Funding KES 30,000,000.
- 2011-2013: ASARECA project. Building Public Private Sector Partnership to Enhance the Productivity and Competitiveness of Aquaculture in Eastern and Central Africa (ECA) region, Co-PI, Assistant Country Project Coordinator, Kenya. Funding of U$D 264,735.91
MEMBERSHIP TO PROFESSIONAL BODIES
- Member of World Aquaculture Society (WAS)
- Member of Aquaculture Association of Kenya (AAK)
- Member of African Women in Science and Engineering (AWSE)
- Member of Mentoring neTwork for African Women in Academia (MTAWA)
- Member of Sustainable Aquaculture Research Networks in Sub Saharan Africa (SARNISSA)
- Member of AquaHub
- Member of MASHAV’s Shalom Club
- Member of Red Cross Society of Kenya
- Alumni of Kenyatta University
- Alumni of Moi University, Kenya