Showing papers on "Protein sparing published in 2003"
TL;DR: The results show that productivity of Asian seabass can be markedly improved by increasing dietary protein and lipid concentrations, however, they appear to have only a limited capacity to use lipid as a primary energy source.
101 citations
TL;DR: Weight gain of silver perch fed diets containing wheat meal or carbohydrates at 45% inclusion content had significantly reduced weight gain when compared with fish fed the basal diet, and protein retention and energy retention efficiency were similar or better.
Abstract: The ability of juvenile silver perch (Bidyanus bidyanus) to utilize dietary raw wheat meal, raw wheat starch, gelatinized wheat starch and dextrin as energy sources to spare protein for growth was quantified. Energy utilization and protein sparing were assessed by comparing the weight gain, energy retention efficiency, protein retention and body composition of silver perch that had been fed a series of diets in which the basal diet (low carbohydrate) was systematically replaced with graded levels of each carbohydrate ingredient or an inert diluent, diatomaceous earth. The protein content decreased as the carbohydrate content increased, giving four different protein to energy ratios for each of the four carbohydrate sources (except for the 60% inclusion level, at which only three carbohydrate sources were tested). Silver perch were efficient at utilizing carbohydrate for energy to spare protein. Silver perch fed diets containing up to 30% wheat meal, raw wheat starch, gelatinized wheat starch or dextrin exhibited similar growth, protein retention and energy retention efficiency to the fish fed the basal diet. Weight gain of silver perch fed diets containing wheat meal or carbohydrates at 45% inclusion content had significantly reduced weight gain when compared with fish fed the basal diet. However, protein retention and energy retention efficiency were similar or better. Whole-body protein levels of silver perch remained constant regardless of carbohydrate sources, and there was no evidence of increasing whole-body lipid concentrations for fish fed diets with up to 60% dietary carbohydrate. Silver perch were more efficient at utilizing processed starch (either gelatinized starch or dextrin) than wheat meal or raw wheat starch.
95 citations
TL;DR: Five diets were formulated to provide an isoproteic daily dietary intake of 15 g kg-1 day-1, while maintaining daily starch intake ranging from 0 to 40 gkg-1 week-1 to show the protein sparing action of starch in both species.
Abstract: Five diets were formulated to provide an isoproteic daily dietary intake of 15 g kg-1 day-1, while maintaining daily starch intake ranging from 0 to 40 g kg-1 day-1. The 4-week experiments started with initial mean weights of 4.7 and 4.4 g for Pangasius bocourti and P. hypophthalmus, respectively. The results clearly show the protein sparing action of starch in both species. Best protein retention was obtained with starch intake of 20 and 10 g kg day-1 for P. bocourti and P. hypophthalmus, respectively, which was equivalent to 40 and 20% starch in the feed. Pangasius bocourti and P. hypophthalmus fingerlings attained maximal growth with starch intake of 30 and 10 g kg-1 day-1, equivalent to 60 and 20% starch in the feed. It was noted that body lipid accumulation was much higher in P. bocourti than in P. hypophthalmus, and that excess dietary starch intake depressed diet digestibility and growth. (Resume d'auteur)
42 citations
TL;DR: It is concluded that dietary RNA supplementation had no nutritive value for European sea bass and nitrogen retention was significantly improved with the decrease in dietary protein level.
20 citations
TL;DR: Data indicate that currently available commercial feeds for summer flounder may be over-formulated and show a need for further research to determine specific and accurate nutritional information for this species.
Abstract: The ability of juvenile summer flounder Paralichthys dentatus to utilize dietary lipid as energy, and the effect of dietary lipid on weight gain and body composition was investigated in a 12-week feeding trial. Diets were formulated to provide 55% crude protein from herring meal and casein. Menhaden oil was added to produce diets with 8, 12, 16 or 20% total lipid while providing 16.0 kJ available energy/g dry diet. The diet containing 20% total lipid supplied 16.7 kJ available energy/g dry diet due to the high levels of protein and lipid. An additional diet was included to reproduce currently available commercial diet formulations for flounder, providing 55% crude protein supplied solely from herring meal and 16% total dietary lipid. Juvenile summer flounder (initial weight 23 g) were stocked into triplicate aquaria in a closed, recirculating system maintained at 20 C. Fish were fed 2% of body weight each day divided into two equal feedings. Upon termination of the study, effects of dietary lipid on weight gain, body condition indices, and proximate composition were determined. Weight gain (96-149% of initial weight), feed efficiency ratio values (0.43-0.48). fillet yield, and whole-body composition all were unaffected by dietary lipid level. High levels of dietary lipid did increase the lipid content in the finray muscle, as fish fed diets containing 16 and 20% dietary lipid had significantly higher lipid levels than fish fed the diet containing 8% lipid. No apparent protein sparing effect of lipid was observed. These data indicate that currently available commercial feeds for summer flounder may be over-formulated and show a need for further research to determine specific and accurate nutritional information for this species.
5 citations