Africa Journal of Animal and Biomedical Sciences 5 (3), 2010 ISSN: INABSTA

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1 Africa Journal of Animal and Biomedical Sciences 5 (3), 2010 ISSN: INABSTA Use of May flies (Ephenoptera) as total replacement of Rastrineobola argentea in diets of catfish (Clarias gariepinus) in Lake Victoria Basin A. Tamale 1, T. Sifuna Mayende 2, K. Glaston Mwangi 3 M. Ayieko 4, M. F.O Ndonga 4, T. Otude 2 1 Makerere University P.O.Box 7062 Kampala andietam@gmail.com 2 Busoga University.. P.O.Box 154 Iganga. 3 Jomo Kenyatta University of Agriculture and Technology. P.O Box 62000, Nairobi, Kenya 4 Maseno University. P. O. BOX 33, Maseno Abstract The lack of appropriate livestock feeds at affordable prices has greatly contributed to the slow pace of development in aquaculture and agriculture particularly in Uganda and other parts of the Eastern African region. A study was carried out to determine the nutrient composition of the May flies and growth and feed conversion rates of Clarias gariepinus stockers fed on mayflies, cassava and premix in relation to standard fish feeds in happas for 90 days. Proximate analysis of the dried powder was done using AOAC methods. The oil characterization was done using Blair and Drier methods. The design trial was a simple random and double blinded field controlled study. The stockers measuring10 gms and cm were put in happas with a stocking density of 20 fingerlings per happa put two metres apart and the interventions were done in duplicates. The interventions involved the administration of feeds (type A, B and C). Feed type A was cassava only (used as the control); type B was cassava and mayflies (47.5% constant protein) and vitamins premix top up; and type C was standard feed. Vital parameters growth, feed gain ratio and feed conversion ratio were monitored. May flies had a crude protein of ± 1.23% on dry weight basis as compared to Rastrineobola argentea (Haplochromines) (59%) the common source of protein in livestock feeds and were rich in the macro and microelements crucial in the growth of the fish hence was recommended as a suitable replacement for the fish meal. Feed type B accounted for the highest total weight gains (p<0.01) and also had the lowest FCR ranging from which ranked the first as compared to the standard (feed type C) which had FCR ranging form In conclusion, feed type B had the lowest feed conversion ratio amongst the feed types studied hence May flies acted as a perfect replacement for the fishmeal in the fish diets. Key words: Clarias gariepinus, May flies, fish feed, value addition Introduction According to (1), the trade in fish and fish products was a growing economic sector in the COMESA region with an annual value of at least US$765m, though much of the actual trade was unreported and under valued. However, the lack of appropriate livestock feeds at affordable prices has greatly contributed to the slow pace of development in aquaculture and agriculture particularly in Uganda and other parts of the East Africa (1). The quality of the feed is determined by its composition and the extent to which the nutrients are digested and assimilated. Fish fed only on carbohydrates have lower growth rates since the fish spends too much energy digesting the nutrients (2). Proteins are used for livestock growth if adequate levels of fats and carbohydrates are present in the diet (3.); hence the need to balance nutritional requirements through feed formulation. Rastrineobola argentea (Haplochromines) has been the major protein source (59%) for livestock species since it that allows high protein digestibility and the amino acid profile that closely matches the fish and poultry dietary requirements (4). On the other hand, Haplochromines has other competing needs especially food for human and its use as a medicament. Afri. J. Anim. Biomed. Sci.,5 (3): , (2010) 99

2 Against the above background it became apparent that there was a need to seek for alternative protein feed sources for the livestock especially the use of mayflies. May flies have been observed to plenty (5). During periods when the mayflies are plenty, it has been observed that the catch of fish increase tremendously (5). This hinted that probably mayfly proteins may meet the fish and livestock requirements. This study was therefore deisgned to find out whether mayflies could be used as a total replacement of Rastrineobola argentea in diets of catfish (Clarias gariepinus) in Lake Victoria Basin Materials and methods A study was carried out to determine the nutrient composition of the Mayflies and also determine the growth and feed conversion rates of Clarias gariepinus stockers fed on Busoga 1 diets (mayflies, cassava and premix) in relation to standard fish feeds in happas for 12 weeks. The may flies were collected, classified, sun dried and then powdered for laboratory experimentations. Some were stored under cold conditions. Proximate analysis of the dried powder was done using AOAC methods of analysis. The oil characterization was done using Blair and Drier methods and this was carried out in JKUAT, Kenya. The research design was a simple random and double blinded field controlled trial. The stockers (average weight of 10 gms and length of cm) were put in six happas with a stocking density of 20 fingerlings per happa. Each happa was two metres apart and the interventions were done in duplicates; the trials went on for 12 weeks (6) in Uganda as shown in Figure 1. The interventions involved the feeding of fingerlings with 3 types of feeds: A, B and C. Feed type A was cassava only (used as the control), feed type B was consisting of cassava, mayflies (47.5% constant protein) and vitamins premix top up and feed type was a standard feed. Biweekly weight gains (gms) and lengths (cms) of the fingerlings were taken. Weekly amounts of feed consumed (gms) by fingerlings was determined. Water parameters were monitored using Viscolor water kit at the source and when sampling. Feed Conversion Ratio (FCR) was determined using the formula given by below (7). FCR was taken as the amount of food required to produce a unit of fish. FCR = total amount of food given (kg) Total amount of weight gained (kg) The vital parameters growth, feed gain ratio and feed conversion ratio were analyzed using R version ( ) Inc software. Figure 1: Happas set up for the field trial Afri. J. Anim. Biomed. Sci.,5 (3): , (2010) 100

3 Weekly total feeds Results The results of proximate analysis, mineral composition and fatty acid classification of mayflies were as shown in Tables 1 and 2 respectively. The relationship between feed types and feed amounts (g) were as shown in Figure 2 and relationship between total weight of fish (g) and the feed types were as shown in Figure 3. The feed conversion ratios of fingerlings feed on different feeds were as shown in Table 4. Feed B had highest total weight gains which was statistically highly significant ( , p<0.05). The average water parameters (ppm) at source and in between happas with the different treatments were as shown in Figure 4. Table 1: Proximate analysis of May flies Item Percentage of sun dried mayfly Moisture content (%) 11.6 ± 0.58 Ash (%) 4.00 ± 0.08 Crude Protein (%) ± 1.23 Crude fat (%) ± 0.26 Crude fibre (%) * All values except moisture content expressed as means ± SE on dry weight basis A B C Feed type Figure 2: Relationship between feed types and feed amounts Afri. J. Anim. Biomed. Sci.,5 (3): , (2010) 101

4 Table 2: Mineral composition (mg/100g) of the May flies Mineral Mg/ 100g of sundried mayfly Calcium ± 0.65 Magnesium ± 0.58 Potassium ± 1.15 Sodium ± 1.47 Phosphorous ± 1.79 Iron ± 0.99 Zinc 5.62 ± 0.25 Manganese ± 0.87 Copper ± 0.36 All values expressed as means ± SE on dry weight basis Table 3. Percentage fatty acid composition of the lipid fraction in may flies Fatty Acid Capric acid (C10:0) Lauric Acid (C12:0) Myristic Acid (C14:0) Palmitic Acid (C16:0) Palmitoleic Acid (C16:1) Stearic Acid (C18:0) Oleic Acid (C18:1) Linoleic Acid (C18:2) Linolenic Acid (C18:3) Total saturated 1 Total Unsaturated 2 Monounsaturated 3 Polyunsaturated 4 % composition 1.38 ± 0.01 a 0.18 ± 0.01 a 2.73 ± 0.01 a ± 0.05 a 5.24 ± 0.04 a ± 0.07 a ± 0.36 b 0.5 ± 0.01 d Nd ± 0.25 a ± 0.38 c ± 0.69 b 0.5 ± 0.01 d *Values on the same row follows by the same letter are not significantly different (p<0.05) a Fatty acid content expressed as percentages of total methyl esters. Fatty acids are denoted by their common name, number of carbons and number of double bonds. 1 Sum total percentage of 10:0, 12:0, 14:0, 16:0, 18:0 2 Sum total percentage of 16:1, 18:1, 18:2, 18:3; 3 Sum total percentage of 16:1, 18:1 4 Sum total percentage of 18:2, 18:3 nd- Not detected Table 4. Feed conversion ratios of the different feeds Feed type Total weight Total feeds FCR A A B B C C A1, B1 & C1 are duplicates of feed type A, B &C respectively Afri. J. Anim. Biomed. Sci.,5 (3): , (2010) 102

5 Figure 3: Relationship between total weight of fish and the feed types Figure 4: Water parameters at source and between happa treatments Discussion Fish feeding is the most important task in the intensive pond production of catfish, and the person responsible for feeding should be an experienced fish culturist. Catfish can be seen only when they are coming up to feed, and their feeding behavior can be an important clue to general health and to other conditions in the pond. This observation is in agreement with (Edwin H. Robinson 1998) who Afri. J. Anim. Biomed. Sci.,5 (3): , (2010) 103

6 observed that feed used in commercial catfish production must contain all essential nutrients at adequate levels to meet total nutritional requirements of catfish for normal growth and development. The fish mainly utilize proteins for the growth and development and if the feeds don't have a protein percentage between 28-36% stated then growth slows (Edwin H. Robinson 1998). Also there is decreased resistance to stress and diseases (8). From the proximate analysis, it was revealed that mayflies had a crude protein of 72 ± 1.23% on dry weight basis. This was higher than that of Rastrineobola argentea (Haplochromines) (59%) the common source of protein in livestock feeds (4). Hence it a suitable replacement for the fish meal. The mayflies were observed to be rich in macro and micro elements which are crucial in the growth of the fish. These elements are crucial in solving the deficiencies like scoliosis, bone defects of fish (7) Usually several factors should be considered when feeding fish. These includes: the species of fish being cultured, age (larvae, fry or adult fish) and also the quality of feed being used (nutritional quality, type, size and texture of the pellet). Since the crude fat percentage was less than 15% then the keeping quality of the mayflies after drying would not be problematic and the fats have a vast role in energy production and general body functioning. Excess fats in the diet lead to hepatomas and enhanced rancidity of the feeds. Based on the fact that the performance of the feed did not only depend on its quality but also on the feeding regime (9), the feeding trials were needed to test the formulated feeds. This was in agreement with earlier studies (9,10) who observed that in the case of intensive pond based farming systems attention was focused on the need to further improve feed formulation, feed manufacture, and on-farm feed and water management so as to maximize feed intake and feed efficiency, and minimize feed wastage and water pollution. The constant percentage of proteins (47.52%) was used. This was mid way between the replacement trials which used 33-66% protein. This was in agreement with Gomes (11) and (8) who used 30% protein diets to test digestibility as an functionality of amino availability for fish diets using grains and fish meal. The study revealed that feed type B (test feed) gave the highest total weight gains followed by feed type C(standard feed) and lastly feed type A (control feed). This was in agreement with (2.) who observed that fish which feed on carbohydrates spend excess energy digesting the former hence accounted for the least growth for feed type A. On the other hand, feed type B accounted for the highest total weight gains which was statistically highly significant ( , p<0.05). This was in agreement which was earlier made by (3.) who observed that proteins were only used for adequate growth if carbohydrates and fats were properly balanced through feed formulation. The feed conversion ratio (FCR) is one of the vital indicators of feed performance in relation to growth and the lower the better. Feed type B had the lowest FCR ranging from which ranked the first as compared to the standard (feed type C) which had FCR ranging from in accordance with (8) The smaller the ratio, the better the feed. A figure greater than 2 is not good enough. Water quality was significantly affected by feed type (floating vs sinking), regime (once vs twice daily), condition of the fish and source of the water. Feed accumulation in water was as a result of feeding stressed fish. This does not only deplete the remaining low amounts of oxygen in the water but also releases ammonia which is toxic to the fish by causing bronchial hyperplasia especially when the ph of the water is high above 7.5 (13). At low ph the amount of ammonia is considered negligible and it should not exceed 0.02mg/l litre. During this study the mean ammonia levels were 0.4 ppm at the water source while at the happas it reached about 1ppm which was way above the expected range according to (14). In conclusion, feed type B had the lowest feed conversion ratio amongst the feed types studied hence mayflies not only had higher crude protein percentage (72%) than Rastrineobola argentea (59%) but could also act as a perfect replacement for the fishmeal in the fish diets diets. Further studies should be done the feed conversion efficiency for different livestock species using mayflies as the principal source of proteins. Acknowledgements We are grateful to the VicRes / IUCEA and SIDA SAREC for funding the research. Special thanks go to the teams from Makerere, Busoga, Maseno,Jomo Afri. J. Anim. Biomed. Sci.,5 (3): , (2010) 104

7 Kenyatta and Universities for all the efforts and facilities availed for this research. References 1. Network (wougnet)., W. O. U "Plan for the Modernisation of Agriculture (PMA)." Retrieved 6th May 2009, from ma_ug.htm 2. Nalwanga, R The effect of soyabeans, mukene (haplochromines), maize bran and potato peels on the growth of Nile tilapia (Oreochromis niloticus) under laboratory conditions. zoology Kampala,Uganda, Bachelor of Science, Makerere University, 47p. 3. Craig, S. H., L.A Understanding Fish Nutrition, Feeds and Feeding. Knowledge for the common Wealth. Virginia Cooperative Extension, 420( 256). 4. Centre, K. A. R. D Aquaculture Extension Manual kampala, Kajjansi Aquaculture Research Development Centre. 5. Ayieko, M. A Termites and mayflies in the food chain of ASAL: Prospects for value addition.. Dry land ecosystems: challenges and opportunities SNRM RPSUD. 6. Webster, C.D. J. H. T., Laura S. Goodgame, Daniel H. Yancey, Mackey, L Use of soybean meal and distillers grains with solubles as partial or total replacement of fish meal in diets for channel catfish (Ictalurus punctatus). Aquaculture, 106(3-4): Rutaisire, J. B., Gladys; Walekhwa, P., Kahwa, D Fish farming as a business. Kampala Uganda Fountain publishers. 8. Robinson,Edwin H., Meng H. Li and Martin W. Brunson Feeding Catfish in Commercial Ponds.. SRAC, Southern Regional Aquaculture Center Lojjo, M. D Effects of supplementary feeding on growth of cultured Tilapia in Lukuhnu, Bukanga sub-country. Animal science and fisheries. Bachelor of Science Special project Iganga,Uganda, Busoga University 35p. 10. Tacon A. G. J., Phillips,M. J. Barg U. C Aquaculture feeds and the environment: the asian experience. Water Science and Technology 31(10): Gomes,E.F., Sadasivam, P.R., Kaushik, J Replacement of fish meal by plant proteins in the diet of rainbow trout (Oncorhynchus mykiss): digestibility and growth performance. Aquaculture 130(2-3): Hossain, K. J Studies on the protein, energy and amino acid digestibility of fish meal, mustard oilcake, linseed and sesame meal for common carp (Cyprinus carpio L.) " Elsevier B.V 13. Brown, L Aquaculture for veterinarians: fish husbandry and medicine. oxford, pergamon press ltd. 14. Tamale, A., Ejobi, F., Rutaisire, J, Isyagi, N., Nakavuma, J., Nyakarahuka, L., Amulen, D Implication of aquaculture production husbandry practices on fish health in Uganda. Africa Journal of Animal and Biomedical Sciences, 5(1): Afri. J. Anim. Biomed. Sci.,5 (3): , (2010) 105