Effect of fermentation on the nutritive value of sesame seed meal in the diets for rohu, Labeo rohita (Hamilton), fingerlings

Six isonitrogenous (350 g kg(-1) crude protein) and isoenergetic (17573 kJ kg(-1)) experimental diets incorporating raw and fermented sesame (Seasamum indicum) seed meal at 200, 300, and 400 g kg(-1) into a fishmeal based diet were fed to rohu Labeo rohita fingerlings for 60 days and the growth performance and feed utilization efficiency of the fish was studied. The antinutritional factor phytic acid, from raw sesame seed meal, could be reduced below detection limit by fermentation with lactic acid bacteria (Lactobacillus acidophilus). Fermentation of the oilseed meal resulted in reduction of the tannin content from 20 to 10 g kg(-1). In terms of growth response, feed conversion ratio and protein efficiency ratio, a diet containing 400 g kg(-1) fermented sesame seed meal resulted in a significantly (P < 0.01) best fish performance. In general, growth and feed utilization efficiencies of fish fed fermented sesame seed meal diets were superior to those fed raw oilseed meal diets. Apparent protein digestibility (APD) values decreased with increasing levels of raw oilseed meal. APD was, however, significantly (P < 0.01) higher at all levels of incorporation of fermented sesame seed meal, while diets containing raw oilseed meal resulted in poor protein and lipid digestibility. Carcass protein and lipid contents of fish fed fermented sesame seed meal diets increased with increasing level of incorporation, being highest with 400 g kg(-1) fermented oilseed meal-containing diet. The results showed that sesame seed meal may be incorporated in carp diets up to 200 g kg(-1) and 400 g kg(-1) in raw and treated (fermented) forms respectively.