Performance of Palm-based oils in replacing FO as aquafeed ingredients for warm freshwater fish -A review of dietary FO replacement studies with selected species. by Mohammed Aliyu Paiko Aquaculture Research Group, School of Biological Sciences Universiti Sains Malaysia, Penang-Malaysia moleepaiko@yahoo.com
-INTRODUCTION- Why the interest in the Aquaculture of freshwater fish species.? Marine culture 36.10% Brackish water culture 7.40% Freshwater species 56.50% Total Global Aquaculture production, 2004 (FAO, 2007)
Why MUST we replace FO in Aquafeeds.? The sustainable supply of FO to meet demand Aquaculture currently consumes 70-80%, by year 2010 ~85-88% and estimated that by year 2020, demand will exceed total supply! Development of Aquaculture MUST ensure the conservation of Marine resources Growth in Aquaculture production has been accused of the depletion in some pelagic fish species The current EU restrictions on PCBs/dioxins in animal feed may extend to Aquaculture, globally PCBs/dioxins and other toxic materials found in cultured fish have been linked to FO
Continued. Moreover, the current level of inclusion of FO in feeds for warm freshwater species COULD be in excess and thus the need to reduce the excessive use. Results of some FO replacement studies in freshwater fish indicate
What are the FA requirements of warm freshwater fish..? Demonstrated requirement for n3 and n6 series of PUFA OR for the n6 series alone Kanazawa (1985); De Silva and Anderson (1995) Freshwater fish species generally, do not encounter much n3 HUFA in their natural diets Bell et al. (2002) VO have been shown to be readily catabolized for energy by many warm freshwater species Al-Owafeir and Belal (1996); Varghese and Oomen (2000); Ng et al. (2004)
Continued. Preferential use of SFA and MUFA for energy production in the mitochondrial system of fish Henderson and Sargent (1985) Most studied warm freshwater fish show the conventional freshwater fish pattern in bioconversion of 18:2n6 and 18:3n3 to their longer chain homologues (ArA, EPA & DHA) Sargent et al. (2002); Torcher et al. (2006) Thus, in most freshwater fish, EFA requirements can be met by supplying 18:3n3 and/or 18:2n6 Bell and Sargent (2003)
-PALM OIL/REFINERY PRODUCTS- What are Palm-based oils.? Oil Palm Fruit bunch Oil extraction Palm Kernels Crude Palm oil Oil extraction Bleaching Deodorization & Distillation Spent Bleaching Clay Palm Kernel Meal Crude Palm Kernel Oil Palm Fatty Acid Distillate RBD Palm oil Fractionation Refining process of crude palm Oil (Adopted from Ng et al., 2003)
Production vol. (x '000) Tons -DISCUSSION- Palm-based oils more suitable to replace FO in feeds for warm freshwater fish.? 1. Sustained increase in production volume in response to global demand.. Comparison of Global FO and CPO production by year from 1980 FO CPO 40000 35000 30000 25000 20000 15000 10000 5000 0 1980 1985 1990 1995 2000 2005 2006 YEAR Adopted with permission from Turchini et al. (2009)
Continued. 2. Comparatively cheaper and relatively more stable price than FO Peruvian Fish oil & Soya oil Price History (1984-2008) Source: Globe Fish
Continued. 3. Palm-based oils produce comparative or better growth performance in warm freshwater fish than FO In Tambaqui fingerling Viegas and Cotreras (1994) In Nile Tilapia fingerling Al-Owafeir and Belal (1996); Ng et al. (2001) In African catfish Lim et al. (2001); Ng et al. (2004) In Climbing perch Varghese and Oomen (2000) In iridescent shark fingerling Asdari et al. (2009, accepted manuscript) In snakehead fry Aliyu-Paiko et. al (manuscript under review) In Bagrid catfish Ng et al. (2000)
Continued. 4. Additional benefits of Palm-based oils in diets for warm freshwater fish species Improved protein retention (protein sparing effect) Lim et al. (2001) Resistance of feed to oxidation (low PUFA) and reduction in rancidity (abundance of natural anti-oxidants; carotenoids and Vit. E) Ng et al. (2004) Higher oxidative stability in fish fillet (increased deposition of Vitamin E in the muscle) Wang et al. (2006) Reduction in lipid peroxidation, Increased shelf life of fish products Ng et al. (2004)
Continued. 5. Absence/low levels of pollutants and potentially toxic substances in Palm-based oils PCBs/dioxins and other pollutants detected in fish products have been traced to FM & FO and the sea environment WHO (1999); Jacobs et al. (2002); Karl et al. (2003) Most of the sources of these pollutants in the environment have been or are in the process of being banned Turchini et al. (2009) Diets supplemented with VO have been reported to substantially reduce levels of these pollutants Bell et al. (2005); Berntseen et al. (2007)
What are the concerns of feeding diets containing Palm-based oils to warm freshwater fish.? Low n-3 PUFA content of fish and relatively high n-6 PUFA content (especially 18:2n6) Bell et al. (2001); Ng (2002); Jobling et al. (2002); Regost et al. (2003) To overcome this, feeding a finishing diet has been recommended containing rich sources of n-3 PUFA Bell et al. (2001); Ng (2002) However, CPO has lower potential for the deposition of the undesirable 18:2n6 in fish compared to other VO Nesaretnam and Muhammad (1993); Ng et al. (2007)
-CONCLUSSION- Based on the reasons presented and discussed above, it is concluded that; Palm-based oils are more suitable to replace FO in diets for many warm freshwater fish species
Acknowledgement I wish to acknowledge the contributions of the following: The Universiti Sains Malaysia Fellowship program and travel grant scheme, for making this presentation possible Professor Roshada Hashim, My supervisor and Dean, graduate School (IPS, USM), for her support & supervision of my PhD studies Dr Turchini, GM and Dr Ng, WK for the permission to use some of their materials for this presentation
THANK YOU!