The potential of soil and agro-allied waste substrates in vermiculture was assessedin terms of their efficiency for growth, reproductive performance and zoomass production of cultured earthworms (Hyperiodrilus euryaulos). Four wooden boxes were stocked in duplicates with 50 matured H. euryaulos of average weight 1.94`0.2 g and cultured for 12 weeks. Harvested earthworms were dried, used to formulate five 42.5% isoproteic diets and 1900 kJ/100 g isocaloric diets and fed to fingerlings of Heterobranchus longifilis for 70 days. In both vermireactors, the earthworm grew very well with significantly different (p< 0.05) mean weight gain, 304.25 and 208.15 g ffom agro-allied and soil substrate respectively. Significantly (p< 0.05) higher specific growth rate of 0.73% day-1 and reproductive performance of 2,120 worms kg-1 of substrate were from agro-allied substrate compared to 0.59% day-1 and 1,914 worms kg-1 of substrate, respectively from soil substrate worms. The highest percentage weight gain, 400.5% fish-1 and specific growth rate of 0.999% day-1 were in fish fed control diet. The lowest feed conversion rate, 1.51; highest protein efficiency ratio, 1.52 and apparent net protein utilization, 52.48% were from 25% earthworm meal diet. The highest daily energy gain 3.34 kJ fish-1 day-1 was from the control diet. There was significant differences (p< 0.05) between the growth and feed utilization indices. Haematocrit level, haemoglobin concentration and leucocyte count improved with earthworm inclusion levels. The highest profit index, 9.33; lowest incidence of cost, 1.17 and highest cost benefit, 2.38 were from 25% earthworm meal diet. Based on results from this study agro-allied waste substrate could be a better culture substrate for H. euryaulosthan soil substrate and 7.5 to 25% earthworm meal inclusion is recommended in the diet of H. longifilis fingerlings for profitable and sustainable aquaculture practices.
O.A. Sogbesan, A.A.A. Ugwumba, C.T. Madu, S.S. Eze and J. Isa, 2007. Culture and Utilization of Earthworm as Animal Protein Supplement in the Diet of Heterobranchus longifilis Fingerlings. Journal of Fisheries and Aquatic Science, 2: 375-386.