Dietary value of different vegetable oil in black tiger shrimp Penaeus monodon on the presence and absence of soy lecithin supplementation: effect on growth, nutrient digestibility and body composition

Sunflower oil, peanut oil, palm oil and sardine oil were evaluated for their dietary value in juvenile Penaeus monodon in the presence or absence of soy lecithin (SL). Eight isonitrogenous and isocaloric diets were formulated to contain each of the oils as the lipid source. Evaluation was based on the growth performance of shrimp (for 42 days) and apparent digestibility coefficients (ADC). The ADC of the diets was determined by comparing concentrations of the digestibility marker, chromic oxide in the feed and faeces of the shrimp. Shrimps fed diets containing vegetable oil with SL had significantly higher values ( P b0.05) than those fed diets containing the same oil without SL in all the performance parameters tested. No significant differences ( P N0.05) were observed among SL supplemented dietary treatments, although weight gain and feed efficiency were higher in shrimp fed diets containing peanut oil (PNL) and sardine oil (FOL) respectively. Among the dietary treatments without SL, shrimp fed sardine oil diet (FO) had significantly ( P N0.05) higher values than other diets in all the performance parameters tested which did not differ from those fed SL supplemented diets. There was no significant difference ( P N0.05) in survival of shrimp among the dietary treatments. Though apparent dry matter digestibility (ADMD) was not significantly differed among dietary oils, there exists a significant difference in ADC for crude protein, crude lipid and energy. All SL supplemented diets showed a marked increase in apparent crude lipid digestibility (ACLD) than the diets without SL. A high correlation was found between dietary phospholipid (PL) level and ACLD (r =0.95; P b0.05) of the experimental diets. Carcass composition of shrimp fed the different vegetable oil sources was similar. However, the lipid content was higher in the shrimp fed diets containing FO and FOL. The fatty acid composition of the test diets was reflected to a certain extent in the fatty acid composition of whole shrimp. The findings of the present work have shown that, shrimp fed vegetable oil supplemented with SL had significantly higher growth and nutrient digestibility comparable to that of sardine oil without SL