Non-gelatinized corn supplemented with alpha-amylase at sub-optimum protein level enhances the growth of Labeo rohita (Hamilton) fingerlings

Abstract

A feeding trial was conducted for 60 days to delineate the effect of both gelatinized and non‐gelatinized corn with or without supplementation of exogenous α‐amylase at two level of protein 35% (optimum) and 27% (sub‐optimum) on growth, tissue composition and protein sparing effect of carbohydrate in the diet of Labeo rohita fingerlings. Three hundred and sixty fingerlings (average weight 10.00±0.15 g) were randomly distributed in 12 treatment groups with two replicates for each. Twelve semi‐purified diets containing either 35% or 27% CP were prepared with different levels of α‐amylase (0, 50, 100 and 150 mg kg−1) and starch type [gelatinized (G)/non‐gelatinized, (NG)] viz. T1 (NG, 35% CP, 0 mg kg−1α‐amylase), T2 (G, 35% CP, 0 mg kg−1α‐amylase), T3 (NG, 27% CP, 50 mg kg−1α‐amylase), T4 (NG, 35% CP, 50 mg kg−1α‐amylase), T5 (G, 27% CP, 50 mg kg−1α‐amylase), T6 (G, 35% CP, 50 mg kg−1α‐amylase), T7 (NG, 27% CP, 100 mg kg−1α‐amylase), T8 (NG, 35% CP, 100 mg kg−1α‐amylase), T9 (G, 27% CP, 100 mg kg−1α‐amylase), T10 (G, 35% CP, 100 mg kg−1α‐amylase), T11 (NG, 27% CP, 150 mg kg−1α‐amylase) and T12 (NG, 35% CP, 150 mg kg−1α‐amylase). The fish were acclimatized to the experimental condition for 24 days during which control diet (NG, 35% CP) was fed. Weight gain percentage, specific growth rate, protein efficiency ratio and apparent net protein utilization of NG corn‐fed groups at 42.43% were significantly higher (P<0.05) than the same level of G corn‐fed groups. We conclude that 42.43% NG corn supplemented with 50 mg α‐amylase kg−1 feed at sub‐optimum level of CP (27%) significantly enhanced the growth and protein in L. rohita fingerling. Addition of dietary α‐amylase to G corn had no added advantage on growth of L. rohita fingerling.

Studies on digestibility and digestive enzyme activities in Labeo rohita (Hamilton) juveniles: effect of microbial α-amylase supplementation in non-gelatinized or gelatinized corn-based diet at two protein levels

“…Thus, there was no need of extra protein to utilize more for energy requirement. This result well correlates with the growth performance of the juveniles (Kumar et al 2006). There was similar growth performance at both sub-optimum (28%) and optimum (35%) levels in CP fed groups.…”

Effect of different dietary raw to pre-gelatinized starch ratios on growth performance, feed utilization and body composition of juvenile yellowfin seabream (Sparus latus)

“…While these results do not agree with many of those reported previously (Wilson 1994;Nankervis et al 2000;Hemre et al 2002;Venou et al 2003;Krogdahl et al 2005), they are in agreed with those from other investigations (Pfeffer et al 1991;Peres and Oliva-Teles 2002;Fu 2005;Kumar et al 2006). Such variations in the results of such dietary experiments may be explained by differences among the experimental fish species used and differences in terms of the processing conditions of the starch or experimental conditions, such as the composition of the experimental diet and the feeding strategy.…”

“…However, other investigators have reported that technological treatment of starch did not improve utilization -rather, it had a negative effect on the growth of rainbow trout Oncorhynchus mykiss (Podoskina et al 1997), European sea bass Decentrarchus labrax juveniles (Peres and Oliva-Teles 2002), southern catfish Silurus meridionalis Chen) (Fu 2005), and Labeo rohita (Hamilton) fingerlings (Kumar et al 2006). These conflicting results may have been due to the experimental fish species used, the processing conditions of the starch and/or the experiment conditions of the particular study.…”

Modulation of key metabolic enzyme of Labeo rohita (Hamilton) juvenile: effect of dietary starch type, protein level and exogenous α-amylase in the diet

“…In common carp and gilthead sea bream, high carbohydrate diets promoted downregulation of gluconeogenesis at molecular level, i.e., gluconeogenic enzyme gene expressions are decreased (Panserat et al 2002). Kumar et al (2006a) reported that non-gelatinized (NG) corn (42.43%) supplemented with a-amylase at a sub-optimum level of crude protein (27%) significantly enhanced the growth of L. rohita fingerlings, but the dietary a-amylase to the gelatinized (G) corn had no added advantage on growth of L. rohita fingerlings. This indicates that digestion is highly influenced by the dietary starch in the feed.…”