Effects of variable feed allowance with constant energy and ratio of energy to protein in a diet for constant protein input on the growth of common carp Cyprinus carpio L.

Abstract

An 11‐week feeding trial was conducted to evaluate the effects of dietary protein and/or energy levels on growth, feed efficiency and proximate composition of juvenile (average weight: 21.5 g) common carp (Cyprinus carpio L.) fed various diets based on constant daily protein input. Five experimental diets were prepared. One group of diets (diets 1, 2 and 3) contained three crude protein (P) levels (35%, 40% and 45%) with a constant gross energy (GE) of 3.8 kcal g−1 diet. The second group of diets (diets 4 and 5) were formulated to contain a GE of 4.3 or 4.9 kcal g−1 diet and 40% or 45% protein levels, respectively, where GE/P was constant at 10.8 kcal g−1 protein. Fish receiving diet 1 served as the control; they were hand‐fed to visual satiety. Feed allowance for diets 2 and 4 was 87.5% of the control. Feed allowance for fish receiving diets 3 and 5 was 77.8% of the control. Thus, all tanks received the same daily protein input. When gross energy in the diets was constant, 3.8 kcal g−1 diet, weight gain of fish fed diet 2 at 87.5% satiation was significantly higher than that of fish fed diet 3 at 77.8% of satiation. When the GE/P in the diets was constant, 10.8 kcal g−1 protein, weight gain of fish fed diet 1 was significantly higher than that of fish fed diet 5 at 77.8% satiation. The feed efficiency ratio (FER) for diets 2–5 was significantly higher than for diet 1 at constant GE and GE/P, and this improved linearly as dietary protein levels increased. The protein efficiency ratio (PER) for diet 2 was significantly higher than for diet 3 at constant GE. However, PER was not significantly different at constant GE/P. Protein retention of fish fed diet 2 was significantly higher than that of fish fed diet 3 at constant GE. Protein retention of fish linearly decreased at constant GE/P. The energy efficiency ratios (EER) for diets 2 and 3 were significantly higher than for diet 1 at constant GE. Moisture and protein contents of the whole body of fish were not significantly different at constant GE, but they decreased linearly at constant GE/P. The lipid content of fish fed diet 1 was significantly lower than that of fish fed diet 2 at constant GE, and body lipid content linearly increased at constant GE/P. These results indicate that growth and feed efficiency for common carp fed a 40% protein diet with 3.8 kcal g−1 diet GE at 87.5% satiation rate was superior to those for the fish fed either a 35% protein diet with 3.8 kcal g−1 diet GE at 100% satiation rate or a 45% protein diet with either a 3.8 or 4.9 kcal g−1 diet GE at 77.8% satiation rate.

Teores de proteína bruta em dietas práticas para juvenis de carpa capim

“…Além disso, como o arraçoamento foi restrito para todos os tratamentos (3% da biomassa), isto impediu o "consumo compensatório" pelos animais que recebiam as menores concentrações proteicas. Quando os peixes são alimentados com ração restrita, eles crescem mais rapidamente com dietas com alto nível proteico, e quando alimentados até a saciedade, eles respondem melhor aos níveis mais baixos de proteína (Cho et al, 2001).…”

Evaluation of Different Commercial Feeds for Culture of Juvenile Sobaity (Sparidentex Hasta Valenciennes) in Kuwait

“…In the present study fish fed diet 2 with low intake of protein in terms of per unit body weight resulted in the highest ANPU and energy retention. It is generally observed in fish that protein retention efficiency increases with low protein intake [19], so less of the dietary protein is either excreted or used as energy substrate. High dietary lipid level in diet 4 (22.7%) did not improve protein retention indicating that no protein sparing effect occurred.…”

Interactive effects of dietary protein level and oil source on proximate composition and fatty acid composition in common carp (Cyprinus carpio L.)

“…Moreover, according to Keshavanath et al (2002), carp growth in low protein diets compared to high protein diets was not significantly affected, which is in line with the results obtained in the present study. Cho et al (2001) noted that weight gain of common carp decreased linearly with increasing protein level in feed. In the trial conducted by Satpathy et al (2003) the same growth parameters were observed in Indian carp (Cyprinus catla) fed diets contained 35% or 40% of crude protein.…”

“…Nowadays it is crucial for the aquafeed industry to optimise the use of dietary protein and to improve protein utilisation in fish feeds. The protein sparing effect has been shown in several studies on common carp (Steffens, 1996;Cho et al, 2001), but an excessive fat accumulation in the fish carcass was observed (Keshavanath et al, 2002). Several studies have examined the replacement of FO with RO or other VO in the diets of cyprinids (Steffens et al, 1995;Pozernick and Wiegand, 1997;Du et al, 2008;Zakęś et al, 2010), and also the use of low protein/high carbohydrates diets (Cho et al, 2001;Khan et al, 2004).…”

“…Common carp utilises carbohydrates efficiently (Manjappa et al, 2011); therefore the use of such diets could allow protein sparing and even improved growth (Cho et al, 2001). The protein-sparing effect represents the utilisation of as much of the available dietary protein as possible for conversion into muscle protein instead of energy production.…”