Appropriate Usage Level of Shrimp Waste Meal as Chitin Source for Feeding Young Crayfish (Astacus leptodactylus Esch. 1823)

This study was conducted to determine effects of shrimp waste meal as natural chitin source at different rates (0 (control), 10, 20, 30 and 40% ) on growth, feed conversion ratio (FCR), survival of young crayfish (1.61±0.04 g and 3.74±0.03 cm) for 60 days. Fifteen glass aquariums (70x30x40 cm) were used in the experiment and 20 individuals were stocked per aquarium (95/m2). The highest of final weight and weight gain were obtained in feed with 10% shrimp waste meal group (3.29±0.23 and 1.66±0.23 g), while the lowest of final weight and weight gain was obtained in fed with 40% shrimp waste meal group (2.75±0.35 and 1.18±0.37 g), respectively. However, non-significant differences were found between final weight, weight gain, specific growth rate, final total length, feed conversion ratio, survival percentage among groups at the end of experimental period. It was concluded that shrimp waste meal as natural chitin source can be used in young crayfish diets up to 40% without adverse effect influence on growth

Canola Meal as an Alternative Protein Source in Diets for Fry of Tilapia (Oreochromis niloticus)

Canola meal was used to replace fishmeal protein in diets for fry of tilapia (Oreochromis niloticus L. 1758) at rates of 0 (control), 10%, 20%, 30%, 40%, and 50%. The diets contained approximately 30% crude protein and 3000 kcal/kg digestible energy. The fry were fed 90 days and the growth, feed conversion ratio, protein efficiency ratio, hepatosomatic index, reno- somatic index, and body composition were determined. The final weight (5.12 g) and feed intake (7.99 g) of fry fed the 10% diet did not significantly differ from those of the control. Weight gains declined beyond this replace- ment level, probably because of increased levels of antinutritional factors, particularly glucosinolates. Whole body percentages for moisture, crude lipid, crude protein, and ash were unaffected by the dietary treatment. Re- sults indicate that protein from canola meal can replace up to 10% of protein from fishmeal in diets for tilapia fry

Use of Fermented Soybean Meal with Whey as a Protein Source for Feeding Juvenile Tilapia (Oreochromis niloticus)

In this study, the effect of fish meal substitution with fermented soybean meal in juvenile tilapia (Oreochromis niloticus, L.1758) diets was investigated. Six experimental diets were prepared by replacing 0 (FM, control), 10% (FSM10), 20% (FSM20), 30% (FSM30), 40% (FSM40), and 50% (FSM50) of the fish meal protein in the control diet by fermented soybean meal with whey (FSMW). The control diet contained no fermented soybean meal. The isonitrogenous and isocaloric diets were fed to juvenile tilapia (initial average weight 0.74 g) for 90 days. Each diet group was fed in triplicate to 24 fish per aquarium. At the end of the experiment, highest growth, feed efficiency, and protein digestibility were found in the group fed the FSM30 diet. Tilapia fed diets containing fermented soybean meal up to 50% fish meal exhibited similar growth, feed conversion ratio (FCR), protein efficiency ratio (PER), and protein digestibility compared with the control diet. However, feed efficiency (FE) was reduced in tilapia fed FSM50 diet. Body composition, hepatosomatic index (HIS) and viscerosomatic index (VSI) were unaffected by the dietary treatment. Results of this study showed that FSMW could replace up to 40% of fish meal protein in juvenile tilapia diet

Growth, Survival and Fatty Acid Composition of Freshwater Crayfish (Astacus leptodactylus) Juveniles Fed Enriched Daphnia magna as an Alternative to Artemia

This experiment was conducted to investigate the effects Daphnia magna enriched with lipid emulsions as an alternative to Artemia, on growth, survival rate, and fatty acid composition of freshwater crayfish (Astacus leptodactylus Esch. 1823). The four treatment groups were (a) unenriched Artemia (UEA), (b) unenriched D. magna (UED), (c) D. magna enriched with redpepper emulsion (DER), and (d) D. magna enriched with anchovy oil emulsion (DEA). All tests were carried out in triplicate for 30 days. The crayfish (mean weight 0.12g) were fed ad libitum once daily. At the end of experiment, the highest eicosapentaenoic acid, 20:5n-3 (EPA) level was found in the DEA group (5.77%). The highest DHA (docosahexaenoic acid, 22:6n-3) level was found in the DER group (2.73%) which was statistically similar to the DEA group. In addition, high n-3 HUFA (high unsaturated fatty acid) levels were detected in enriched D. magna groups with emulsions. However, high EPA levels in enriched D. magna groups with emulsions were not reflected in crayfish tissues, but DHA level was reflected in crayfish tissues fed with anchovy oil emulsion. The crayfish fed with D. magna showed similar growth to that of the Artemia fed groups. The growth of the enriched D. magna groups did not differ