MINISTRY OF EDUCATION AND TRAINING NHA TRANG UNIVERSITY Substitution of fishmeal by soybean meal in diets for Nile tilapia (Oreochromis niloticus): A Case study of Rwanda. Aloys MUSONI Master thesis July, 2014 MINISTRY OF EDUCATION AND TRAINING NHA TRANG UNIVERSITY Substitution of fishmeal by soybean meal in diets for Nile tilapia (Oreochromis niloticus): A Case study of Rwanda. By Aloys MUSONI 54CH344 Thesis submitted in partial fulfillment of the requirements for the award of a Master of Science in Aquaculture Supervisors: Le Anh Tuan, PhD Nguyen Van Minh, PhD June 2014 i Dedication To: God, for his mercies and faithfulness My wife Odette Mukanyandwi, my children Sedric Byiringiro and Sabrine Isimbi ii Declaration I hereby declare that this thesis has been produced by myself and is the result of my own investigations. It has neither been accepted nor submitted for any other degree. All sources of information have been accurately documented. Aloys MUSONI iii Acknowledgements First of all, I wish to express my appreciation to Almighty God for providing a safe environment and strength a long way my studies in Nha Trang University (Vietnam). My sincere gratitude goes to Dr. L. A. Tuan and Dr. N. V. Minh for their advice, guidance and technical support of this thesis. I wish to thank the Government of Rwanda which through PAIGELAC project provided funds for these studies. Likewise, I would like to thank the Government of Vietnam through Nha Trang University for offering admission in master’s programme. I take this opportunity to express my gratitude to all staff of Nha Trang University for their help and creating a warm environment during my stay in Vietnam. Finally, I would like to extend a heartfelt thank you to all students of Nha Trang University for their moral support, kindness and friendship. iv Table of contents Page Dedication i Declaration ii Acknowledgements iii Table of contents iv Abstract vii Abbreviation viii List of tables ix List of figures ix Main parts of the thesis x Introduction 1 Hypothesis and Research Objectives 3 Hypothesis 1 3 Objective 1 3 Hypothesis 2 3 Objective 2 3 Chapter 1: Literature review 4 1.1. World production and Aquaculture of tilapia 4 1.2. Tilapia Aquaculture in Africa 5 1.3. Status of Aquaculture in Rwanda 5 1.4. Perspective or potential of Aquaculture of Tilapia in Rwanda 6 1. 5. Culture systems of Tilapia 8 1.5.1. Cage culture 8 1.5.2. Pond culture 8 v 1.5.3. Raceways systems 8 1.5.4. Recirculating Systems 9 1.6. Environmental factors of Tilapia 9 1.6.1. Temperature 9 1.6.2. Salinity 10 1.6.3. pH and Ammonia 10 1.6.4. Dissolved Oxygen 10 1.7. Nutrient requirements for tilapia 11 1.7.1. Energetics 11 1.7.2. Protein 12 1.7.3. Lipid 12 1.7.4. Carbohydrate 13 1.7.5. Vitamin and minerals 13 1.7.6. Amino acid profile 14 1.8. Tilapia feed characteristics and feeding behavior 15 1.9. Reproduction of tilapia 16 1.10. Digestibility of soybean meal 17 1.11. Limitation of using soybean meal in tilapia diets 18 1.11.1. Trypsin inhibitors 18 1.11.2. Phytic acid 18 1.11.3. Oligosaccharides 19 1.11.4. Saponins 19 1.12. Replacement of fishmeal with soybean meal in feed for Nile tilapia 19 Chapter 2: Material and Methods 21 2.1. Study area 21 2.1.1. Geography and Climate of Rwanda 21 vi 2.1.2. Feeding trial at Kigembe Fish Farming Station 21 2.2. Experimental fish 22 2.3. Ingredients preparation and feed formulation 22 2.3.1. Protein analysis and procedure 23 2.3.2. Lipid analysis procedure 24 2.4. Feeding experiments 25 2.5. Growth parameters 26 2.6. Feed Conversion Ratio (FCR) 26 2.7. Statistical analysis 27 Chapter 3: Results and Discussion 28 3.1. Results 28 3.1.1. Water quality parameters 28 3.1.2. Growth, feed utilization (feed efficiency) and survival 28 3.1.3. Body crude protein (BCP) 31 3.2. Discussion 32 Chapter 4: Conclusion and Recommendations 35 4.1. Conclusion 35 4.2. Recommendations 35 References 36 vii Abstract A feeding trial was conducted at Kigembe fish farming station to determine the effect of fishmeal replacement in the formulated feed by soybean meal on growth, feed efficiency and survival for fry Nile tilapia (Oreochromis niloticus). Five experimental diets were formulated to be isonitrogenous approximately. The diet 1 (control diet) included 100% of fishmeal (FM) while for the other diets fishmeal was partially replaced by soybean meal (diet 2, 75%FM & 25%SBM; diet 3, 50%FM & 50%SBM; diet 4, 25%FM & 75%SBM; diet 5, 0%FM & 100%SBM). The fry of Nile tilapia (body weight 1.34 ± 0.025g) were sorted and stocked into 5 treatments with triplicate groups for each treatment. The experimental units were 15 hapas and all set up in one pond. Feeding ration for each treatment was 10% of total fish biomass over the first 30 days which was divided and offered three times per day. The amount was reduced up to 8% of the total fish biomass for the next 30 days while 6% of total fish biomass was provided during the last 30 days. The results produced showed that the Mean weight gain recorded for the fish fed with diet 2 (75%FM) and diet 3 (50%FM) were not significantly different from that of the fish fed with the control diet (P>0.05). Compared with the control diet, the results of specific growth rate (SGR) were statistically significant (P<0.05) for fish fed with the diet 5 (0%FM) while for the other diets (diet 2, 3 and 4) were not (P>0.05). The mean FCR recorded for the fish fed different amount of SBM did not show a significant difference (P>0.05) compared to the mean FCR recorded for the fish fed the control diet. The mean percentage survival of fish fed with different experimental diets did not show a significant difference (P>0.05). The results produced from body crude protein did not show a significant difference among treatment (P >0.05). The results showed that the total cost to prepare 1kg of feed was considerably reduced with increase in inclusion levels of soybean meal in the diets. The results proved that up to 50% of the SBM could be utilized by Tilapia safely and efficiently as alternative protein source in tilapia diets when the mean weight gain, specific growth rate, feed conversion ratio, survival and body crude protein are considered. Key words: Oreochromis niloticus, Tilapia feed, feed formulation, fishmeal replacement, soybean protein alternative. viii Abbreviation AfDB: Africa Development Bank AOAC: Association of Official Analytical Chemists CGM: corn gluten meal EAA: essential amino acids FAO: Food and Agriculture Organization of the United Nations FCR: feed conversion ratio FFSB: full-fat soybean FM: fish meal IFFO: international fishmeal and fish oil organization MINAGRI: Ministry of Agriculture and Animal Resources MT: million metric tons (MT) PAIGELAC: Inland Lakes Integrated Development and Management Support Project PER: protein efficiency ratio PPV: protein production value RAB: Rwanda Agriculture Board SBM: soybean meal SGR: Specific Growth Rate USAID: United States Agency for International Development [...]... L-methionine totally replaced fish meal in low-fat diets without affecting nutrient utilization of rainbow trout [7] Goda et al [8], comparatively studied growth performance of Nile tilapia and tilapia galilae (Sarotherodon galilaeus, Linnaeus, 1758) fed on fishmeal free diets (100% fishmeal replacement) They found that growth performance of Nile tilapia were reduced when replaced fishmeal by soybean meal. .. performance of Nile tilapia Objective 1 Objective of this study is focusing to formulate a cheap balanced tilapia made feed by replacing 100% of fishmeal (FM) protein with soybean meal protein and to determine the effects on growth, feed conversion ratio (FCR) and survival rate, of tilapia for a period of three months Hypothesis 2 Completed replacement of fishmeal with soybean meal as source of protein... that can enhance natural resistance and feed conversion rate [48] 1.7.6 Amino acid profile In general, Tilapias require the same ten essential amino acids (arginine, histidine, isoleucine, leucine, lysine, phenylalanine, methionine, threonine, tryptophane, and valine) as the other fish and terrestrial animals [49] The supplementation of these EAA into the diets has been a common practice in tilapia. .. of tilapia for a period of three months The outcome of this study will be the design of the cheapest fish feed and affordable by local farmers through using soybean meal as source of protein in tilapia feed instead of using fishmeal 3 Hypothesis and Research Objectives Hypothesis 1 The formulated feed with soybean meal can nutritionally replace fish meal as main source of protein without compromising... traditionally based on fishmeal as the main protein source due to its high protein content and balanced amino acid profile It has the right combination of essential amino acids, fatty acids, vitamins and minerals for fish growth [3] 20 Fishmeal has been the most expensive one among the ingredients used for feed formulation and its availability as well as price fluctuations are threatening the aquaculture industry... fishmeal used by Rwandan farmers to formulate aquafeeds are imported from commercial sources, thus feed price increases, while soybean meal is locally available in different parts of the country which can be used as an alternative protein source The aim of the present study is to evaluate the effect of replacement of fishmeal by soybean meal on growth, feed conversion ratio (FCR) and survival rate, of. .. Status of Aquaculture in Rwanda As a landlocked country, Rwanda s aquaculture relies on its rich fresh water resources About 8% of the area is covered by water (210,000 ha), of which lakes occupy 128,000 ha The country’s lakes are the main source of fish production Principally, Rwanda has a large potential for aquaculture Besides pond aquaculture in watershed areas with sufficient water availability,... 21 plant protein, which contains low amounts of EAA, is a proper diet for fish feeding [57] Chapter 2: Material and Methods 2.1 Study area 2.1.1 Geography and Climate of Rwanda Rwanda is a mountainous, land-locked country on the watershed between the headwaters of the Zaire and the Nile, with an area of 26 338 km2 It includes part of a major freshwater lake, Lake Kivu, numerous smaller bodies of fresh... fingerlings every year The project introduced also the cage culture techniques in lakes A total of 678 cages with volume ranged between 8m3 to 27m3 were installed in Lake Bulera, Ruhondo, Kivu and Muhazi for Tilapia intensive farming [22] The main species cultured in Rwanda is Tilapia nilotica (Oreochromis niloticus) Common carp are also raised in ponds, but on a very small scale Tilapia macrochir and... protein source due to its high protein content and balanced amino acid profile Fishmeal has the right combination of essential amino acids, fatty acids, vitamins and minerals for fish growth [3] Fishmeal has been the most expensive one among the ingredients used for feed formulation Fish made into fish meal are caught from the wild The shortage in global fishmeal production coupled with increased demand . MINISTRY OF EDUCATION AND TRAINING NHA TRANG UNIVERSITY Substitution of fishmeal by soybean meal in diets for Nile tilapia (Oreochromis niloticus) : A Case study of Rwanda. . production and Aquaculture of tilapia 4 1.2. Tilapia Aquaculture in Africa 5 1.3. Status of Aquaculture in Rwanda 5 1.4. Perspective or potential of Aquaculture of Tilapia in Rwanda 6 1. 5 on fishmeal as the main protein source due to its high protein content and balanced amino acid profile. Fishmeal has the right combination of essential amino acids, fatty acids, vitamins and