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

Department of Fish Nutrition and Biochemistry, Central Institute of Fisheries Education, Versova, Mumbai 400061, India.
Fish Physiology and Biochemistry (Impact Factor: 1.68). 06/2009; 35(2):301-15. DOI: 10.1007/s10695-008-9213-6
Source: PubMed

ABSTRACT A 60-day feeding trial was conducted to delineate the effect of both gelatinized (G) and non-gelatinized (NG) corn with or without supplementation of exogenous alpha-amylase, either at optimum (35%) or sub-optimum (27%) protein levels, on blood glucose, and the key metabolic enzymes of glycolysis (hexokinase, HK), gluconeogenesis (glucose-6 phosphatase, G6Pase and fructose-1,6 bisphosphatase, FBPase), lipogenesis (glucose-6 phosphate dehydrogenase, G6PD) and amino acid metabolism (alanine amino transferase, ALT and aspartate amino transferase, AST) in Labeo rohita. Three hundred and sixty juveniles (average weight 10 +/- 0.15 g) were randomly distributed into 12 treatment groups with each of two replicates. Twelve semi-purified diets containing either 35 or 27% crude protein were prepared by including G or NG corn as carbohydrate source with different levels of microbial alpha-amylase (0, 50, 100 and 150 mg kg(-1)). The G corn fed groups showed significantly higher (P < 0.05) blood glucose and G6PD activity, whereas G6Pase, FBPase, ALT and AST activity in liver was higher in the NG corn fed group. Dietary corn type, alpha-amylase level in diet or their interaction had no significant effect (P > 0.05) on liver HK activity, but the optimum crude protein (35%) fed group showed higher HK activity than their low protein counterparts. The sub-optimum crude protein (27%) fed group showed significantly higher (P < 0.05) G6PD activity than the optimum protein fed group, whereas the reverse trend was observed for HK, G6Pase, FBPase, ALT and AST activity. Addition of 50 mg alpha-amylase kg(-1) feed showed increased blood glucose and G6PD activity of the NG corn fed group, whereas the reverse trend was found for G6Pase, FBPase, ALT and AST activity in liver, which was similar to that of the G or NG corn supplemented with 100/150 mg alpha-amylase kg(-1) feed. Data on enzyme activities suggest that NG corn in the diet significantly induced more gluconeogenic and amino acid metabolic enzyme activity, whereas G corn induced increased lipogenic enzyme activity. Increased amino acid catabolic enzyme (ALT and AST) activity was observed either at optimum protein (35%) irrespective of corn type or NG corn without supplementation of alpha-amylase irrespective of protein level in the diet.


Available from: Asim K Pal, Apr 13, 2015
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Experiments were carried out to evaluate efficiency of Labeo rohita to utilize fermented animal protein blend containing slaughter house blood (SHB) and fish offal (FO) as dietary fishmeal (FM) replacer. Five isoproteic (30%), isolipidic (8%) and isoenergitic (15.00 kJ g−1) feed were prepared by replacing 0 (T1), 25 (T2), 50 (T3), 75 (T4) and 100% (T5) FM protein with the fermented blend and fingerlings of L. rohita (mean weight 2.07 g) were fed each of these feed in triplicate groups. The results showed that apparent digestibility coefficient (ADC) of protein significantly increased in T3–T5, while ADC of lipid and total amino acid absorption rate increased in T2–T5 as compared to control (T1). Among the essential amino acids (EAA), arginine exhibited maximum absorption followed by histidine, phenylalanine, valine and lysine while aspartic acid showed a high absorption among the non-essential amino acids (NAA). Fish fed up to 75% of replacement level (T4) did not show any significant difference (P < 0.05) in weight gain (WG), specific growth rate (SGR), feed conversion ratio (FCR), protein efficiency ratio (PER) and apparent net protein utilization (ANPU) between the dietary groups (T1–T4). But FCR was increased and other growth parameters were significantly reduced in 100% replacement group (T5), while body muscle protein was significantly reduced in both T4 and T5. Deposition of EAA (except histidine and methionine) in T4 and NAA (except cystine) in both T4 and T5 in the muscle of fish were also significantly reduced as compared to control (T1). Multi-objective optimization programming technique was used to determine FM replacement level that optimized all the growth parameters (WG, SGR, FCR and PER) simultaneously. By using Global Criterion method, it was obtained that 21.11% replacement of FM by the fermented blend was ideal for optimum growth of L. rohita.
    05/2015; 1. DOI:10.1016/j.aqrep.2015.03.004
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The amelioration effect of dietary high protein and vitamin C against stress was evaluated in spotted murrel, Channa punctatus, exposed to endosulfan. Two hundred and forty fish (average weight: 27.01 g/fish), distributed equally into 4 different groups (control, T(1), T(2), and T(3)), each with 6 replicates were fed with control (40% crude protein, CP and 0.1% vitamin C), T(1) (40% CP and 0.1% vitamin C), T(2) (50% CP and 0.1% vitamin C), and T(3) (50% CP and 0.2% vitamin C) diets for 90 days. Groups fed T(1), T(2), and T(3) diets were exposed to sublethal endosulfan concentration, whereas the control was maintained without endosulfan exposure. Results indicated significant reduction in the growth performance, survival, and activities of lactate dehydrogenase (liver and muscle), malate dehydrogenase (liver and muscle), enzymes of protein metabolism (aspartate amino transferase in liver and alanine amino transferase in liver and muscle), acetyl choline esterase (brain), alkaline phosphatase activity (liver), and ATPase (gill) enzymes of group fed control diet and exposed to endosulfan. However, endosulfan exposed fish fed high CP and vitamin C diet exhibited significant (P<0.05) improvement in their growth performance and metabolic enzyme activities. Further, high CP and vitamin C diet reduced endosulfan accumulation in the muscle. Overall results indicate that vitamin C (0.2%) supplementation in high CP (50%) diet improves growth, metabolism, and reduce endosulfan bioaccumulation in C. punctatus.
    Science of The Total Environment 04/2009; 407(12):3668-73. DOI:10.1016/j.scitotenv.2009.02.031 · 3.16 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Four experimental diets D1, D2, D3 and D4 having 100, 300, 350 and 400 g protein kg−1 diet, respectively, were prepared. Fingerlings of Labeo rohita (5.45 ± 0.03 g) were fed with different diets following a mixed feeding schedule with the feeding cycle of 28 days that consisted of either 28 days feeding of diet D1 or D2 or 21 days feeding with D1 diet and 7 days with either D3 or D4 diet. Different treatments were T1 (D1 for 28 days), T2 (D2 for 28 days), T3 (D1 for 21 days and D2 for 7 days), T4 (D1 for 21 days and D3 for 7 days) or T5 (D1 for 21 days and D4 for 7 days). Fingerlings were sampled after three feeding cycles (84 days). Higher (P < 0.05) growth performance and protein utilization efficiency were found in the T3 group, which was similar to the T2 group. The blood count, NBT, lysozyme activity, serum parameters and stress indicator parameters also complement for the better immunity in the T2 and T3 groups. Therefore, it could be concluded that fingerlings feeding alternately a low-protein diet (D1) for 21 days followed by a normal-protein diet (D2) for 7 days in a cycle of 28 days for 84 days maintained better growth and health status.
    Aquaculture Nutrition 02/2015; DOI:10.1111/anu.12286 · 1.67 Impact Factor