Digestibility and Utilization of Canola Meal in Angel Fish (P. scalare Lichtenstein 1823) Feeds

Abstract

A 12 week feeding experiment was conducted in an aquarium (80x40x40 cm) to determine the potential use of canola meal as a partial replacement of fishmeal in the isonitrogenous (approximately 44% crude protein) diet for angel fish fries with an initial average weight of about 0.91 g. Diets were formulated to include 0, 8, 16, 24, 32 and 40% (CM0, CM8, CM16, CM24, CM32 and CM40, respectively) of fish meal protein as a substitute by canola meal. Growth performance (weight gain, specific growth rate) decreased significantly, when the replacement level of fish meal protein was increased from 24% and higher, the CM40 diet was the lowest in all groups. When the replacement level of fish meal protein 16% (diet CM16) Feed Conversion Ratio (FCR) was the lowest and Protein Efficiency Ratio (PER) was the highest. There were no significant differences in the moisture, lipid, crude protein and ash content in whole body. Fish were fed with pelleted experimental diets to satiation and the feces were collected by siphoning. The apparent digestibility of dry matter ranged from 80.92-88.49%, protein from 91.16-93.71% in the experimental groups. The high level of canola meal in diets was negatively affected in terms of both dry matter and of protein digestibility. These results support the use of canola meal as important replacement protein source for fish meal of angel fish.