Nutritional evaluation of fermented sweet potato leaf meal as a replacer of deoiled rice bran in the diet of Labeo rohita fingerlings.

Abstract

A 60-day experiment was conducted to evaluate the nutritional potential of fermented sweet potato leaf meal (FSPLM) in the diet of Labeo rohita fingerlings. Solid-state fermentation of SPLM with fungus, Chaetomium globosum was was exhibited an increase in the crude protein of SPLM from 21.47% to 31.20% concomitant with decreased crude fibre content from 19.43% to 7.22%. Moreover, anti-nutritional factors such as tannin, phytic acid, trypsin inhibitor, oxalates, alkaloid and hydrogen cyanide HCN were decreased up to 64.95%, 57.51%, 15.31%, 37.32%, 50.00% and 61.70%, respectively. Four iso-nitrogenous (35% crude protein) and iso-caloric (421 kcal GE 100g-1) experimental diets were formulated to substitute the deoiled rice bran with FSPLM viz. Control (0% DORB substitution), SPLM10 (33.33% DORB substitution), SPLM20 (66.67% DORB substitution) and SPLM30 (100% DORB substitution). Growth performance (weight gain % and specific growth rate), feed conversion (feed conversion ratio, feed efficiency ratio and protein efficiency ratio) indices and body composition of L. rohita fingerlings were used as response parameters for dietary treatments. Significantly higher growth rates in L. rohita fingerlings were reported in SPLM10, SPLM20 and SPLM30 groups than the control (p<0.05). Dietary FSPLM did not affect (p>0.05) the feed intake in L. rohita fingerlings. Feed conversion indices did not vary with dietary treatment groups (p>0.05). Whole body composition of L. rohita fingerlings was found to be independent of dietary treatment groups (p>0.05). Therefore, it can be concluded that the fermented sweet potato leaf meal can substitute 100% de-oiled ricebran in the diet of Labeo rohita fingerlings without any adverse effect on growth performance, feed conversion and whole body composition.