A Comparison of nutritional value of Biomar diet and earthworm as feed on growth performance and survival of ornamental Oscar fish (Asteronotus ocellatus)

This experiment was carried out to evaluate the effect of earthworm (Eisenia fetida) in diet for Oscar fish (Astronotus ocellatus) in a randomized design with three treatments in triplicates using 9 aquarium for 9 weeks. Twenty pieces of Oscar fish with average weight 3.6±0.5 g were stocked in each replication. The earthworm meal (as fed) at the levels of 0, 50 and 100% was replaced with Biomar diet in Oscar fish diet. Fish were fed with experiential diets included: 1-Biomar 2- Mixture of Biomar and earthworm meal with equal ratio 3- Earthworm meal. Daily food intake calculated by the weight of fish (3% of body weight) and fish were fed 3 times a day. Physical and chemical properties of water, such as temperature (28.2°C±0.5), oxygen (7.8ppm±0.2) and pH (8.1±0.11), were control.  At the end of study growth performance, feed utility and survival rates were measured. The highest body weight increase (173.2% (gr)±0.23), specific growth rate (2.02 (%)±0.26), average daily growth (17.4 (%)±3.15), protein efficiency ratio (1.85 (%)±0.16) and least feed conversion ratio (0.99 (%)±0.05) observed in Biomar treatment (p<0.05). But greatest survival ratio observed in diet contained earthworm powder. The results assessment showed that neither 50% nor 100% worm meal could not supply Oscar fish nutritional requirements.