ISSN:1353-5773    

DOI:10.1111/j.1365-2095.1995.tb00044.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

AbstractFive oat products, whole oats, oat groats, rolled oats, oat meal and oat bran were tested at five inclusion levels. A growth and a digestibility trial were carried out with rainbow trout,Oncorhynchusmykiss (Walbaum), of 100 g initial mean weight. Protein, lipid and ash digestibilities were only marginally affected by dietary oat levels. Dry matter content of faeces was not affected by any of the oat products. Starch digestibility was high and showed no reduction with increased dietary content. Moderate levels of oats increased weight gain (60‐170 g kg−1), whereas the highest level tested (400 g kg−1), appeared to cause a decrease in gain. Fat content in fish showed a slight increase as dietary incorporations of whole oats, oat bran and oat meal increased. Dressed percentage, however, was only marginally decreased. In fish fed whole oat or oat groat, plasma glucose levels increased as oat inclusion increased. Liver glycogen increased with increasing oat level. There were no clear associations between concentrations of pancreatic hormones and level of oat incorpor

ISSN:1353-5773    

DOI:10.1111/j.1365-2095.1995.tb00045.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

AbstractThe adaptive response of the kinetics of glucose 6‐phosphate dehydrogenase (G6PDH) was studied in trout liver and kidney after feeding (control or high‐protein/non‐carbohydrate diet) or starving for 30 days, as well as influences on growth and other nutritive parameters. Typical Michaelis‐Menten kinetics were found for the hepatic catalysis of G6PDH under all conditions studied, without evidence of sigmoidicity. The administration of a high‐protein/non‐carbohydrate diet (61.0% protein, 7.9% lipids) produced no significant changes in specific activity or other kinetic parameters of the liver enzyme. This nutritional situation caused a significant daily increase in relative growth (20%) and feed efficiency (13.5%), as well as a 13% decrease in the protein‐conversion efficiency, with respect to the control diet (46% protein, 8% lipids, 22% carbohydrates). On the other hand, long‐term starvation (30 days), as a lipolytic condition, significantly decreased the activity and catalytic efficiency of hepatic G6PDH, by almost 45%, without significant changes in the Kmand activity‐ratio values. These changes agree with a fall in the intracellular concentration of the enzyme as a consequence of a protein‐repression process. The activity of the renal G6PDH was less than in the liver of control fish, and no variation in kinetics was found under the high‐protein diet or starvation. This behaviour clearly demonstrates that the kidney pentose‐phosphate pathway showed no adaptive response in relation to synthesis of fatty

ISSN:1353-5773    

DOI:10.1111/j.1365-2095.1995.tb00046.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

AbstractIsoproteic and isoenergetic diets containing 0%, 15%, 30% or 45% heat‐processed cocoa pod husk meal (CPHM) were fed toClarias isheriensis(16.8 ± 2.4 g) for 180 days. Growth rates of catfish fed varying levels of CPHM were similar (P>0.05). Differences in feed‐gain ratio (FGR) or protein efficiency ratio (PER) between treatments were not significant (P>0.05). Histology of the liver showed no pathological effects of incorporation of CPHM. In a second experiment,C. isheriensis(19.1 ± 3.5 g) were fed isoenergetic diets containing 250, 300, 350 and 400 protein g kg−1(protein: energy ratios of 21, 25, 29 and 33 mg protein.kJ−1DE, respectively). Growth rate and FGR improved (P<0.05) in proportion to the dietary protein level. PER decreased with increase in dietary protein. Carcass protein was lowest (P0.05). Body fat was highest in catfish fed 250 g protein kg−1and lowest in fish fed 350 g protein kg−1. These results indicate that CPHM may be a suitable carbohydrate energy source for clariids at a P:E ratio of approximately 29 mg

ISSN:1353-5773    

DOI:10.1111/j.1365-2095.1995.tb00047.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

AbstractYoung Arctic charr,Salvelinus alpinus(L.), mean weight 2.56 ± 0.02 g, were fed nine isoenergetic (˜16.6 MJ digestible energy (DE) kg−1) practical diets formulated to supply digestible crude protein (DCP) at 40g kg−1increments from 230 to 550g kg−1, for 84 days. Mean weight gain (MWG) and specific growth rate (SGR) were determined every 14 days while carcass composition was determined at the start and end of the experiment. Growth responses attained the highest values in the fish fed the diet with 350 g kg−1DCP. Carcass moisture gain, protein gain and apparent net lipid accumulation increased as DCP levels increased to a maximum at 350 g kg−1after which there were no differences among treatments. Total carcass lipid and lipid gain decreased as dietary DCP increased up to 470 g kg−1with no differences thereafter. Apparent net protein accretion decreased with increasing DCP levels up to 350 g kg−1after which there were few differences among treaments. Protein requirements were estimated by fitting MWG and SGR data to broken line regression, quadratic and saturation kinetics models. Results from these analyses suggest that dietary DCP should be provided at between 340 and 392 g kg−1(equivalent to ˜370 and 420g kg−1crude protein) for optimal growth of young Arctic charr reared i

ISSN:1353-5773    

DOI:10.1111/j.1365-2095.1995.tb00048.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

AbstractGrowth studies were conducted to quantify requirements for the essential amino acids (EAA), arginine and histidine inLabeo rohita(Hamilton). Diets incorporating casein and gelatine, as sources of intact protein, supplemented with crystalline amino acids were formulated to a crude protein content of 400 g kg−1. Diets with six graded levels of arginine (14.6, 17.0, 19.0, 21.0, 23.0 and 25 g kg−1) and histidine (3.2, 5.0, 7.0, 9.0, 11.0 and 13.0 g kg−1) were formulated and fed to triplicate groups of juvenile rohu twice a day up to satiation for 60 days. Dietary requirements for arginine and histidine for rohu, estimated using break point analysis, were 23 and 9 of the diet respectively (57.5 and 22.5 g kg−1of dietary protein). Food conversion rate, specific growth rate and survival were better in treatments with diets containing optimum levels

ISSN:1353-5773    

DOI:10.1111/j.1365-2095.1995.tb00049.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

AbstractThe effects of using increasing levels of carbohydrate to replace protein in diets for Atlantic salmon were studied in a long‐term, semicommercial‐scale experiment in sea cages, using wheat and corn starch as carbohydrate sources. The fish were fed extruded diets containing 24 g and 602 g kg−1, 98 g and 521 g kg−1, 165 g and 454 g kg−1, 230 g and 384 g kg−1of carbohydrate and protein, respectively. The contents of lipid were kept constant at 280 g kg−1. The experiment lasted for 9 months until the fish had reached about 4 kg.All groups showed good growth in the experimental period. Feed efficiency decreased and feed intake increased linearly with increased level of carbohydrate in the diet. Digestibility of dry matter and energy were seriously decreased with increased carbohydrate level in the diets. This was mainly due to decreased digestibility of carbohydrate, but also to decreased digestibility of lipid. The digestibility of protein or amino acids was not affected by diet.Higher levels of carbohydrate resulted in increased storage of energy as lipid in fillet and abdominal fat. Red coloration showed an optimum at 98 g kg−1carbohydrate in the diets. No differences in maturation were found between diets.Overall, based on feed efficiency, growth and slaughter quality, the optimum level of carbohydrate in the diet for Atlantic salmon in sea water is found to be approximately 100 g

ISSN:1353-5773    

DOI:10.1111/j.1365-2095.1995.tb00050.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY