Optimum ration level for better growth, conversion efficiencies and body composition of fingerling Heteropneustes fossilis (Bloch)

Abstract

The effects of ration levels on growth, conversion efficiencies and body composition of fingerling Heteropneustes fossilis (6.8 ± 0.04 cm, 5.0 ± 0.02 g) were studied by feeding isonitrogenous (40% crude protein) and isocaloric (19.06 MJ kg -1 gross energy) diets representing 1, 3, 5, 7 and 9% of the body weight (BW) day -1 to triplicate groups of fish . Growth performance of the fish fed at the various ration levels was evaluated on the basis of live weight gain percentage (LWG%), feed conversion ratio (FCR), specific growth rate percentage (SGR%), protein retention efficiency (PRE%) and energy retention efficiency (ERE%) data. Maximum LWG% and SGR were obtained at a feeding rate of 7% BW day -1 , whereas best FCR (1.6), PRE% and ERE% were recorded at a feeding rate of 5% BW day -1 . Maximum body protein was also obtained for the group receiving the diet representing 5% of their body weight. However, a linear increase in fat content was noted with the increase in ration levels up to 7% BW day -1 . The SGR, FCR, PRE and ERE data were also analyzed using second-degree polynomial regression analysis to obtain more precise information on ration level, with the results showing that the optimal ration for these parameters was 6.8, 6.1, 5.9 and 6.2% BW day -1 , respectively. Based on the above second-degree polynomial regression analysis, the optimum ration level for better growth, conversion efficiencies and body composition of fingerling H. fossilis was found to be in the range of 5.9-6.8% of the BW day -1 , corresponding to 2.36-2.72 g protein and 88.20-101.66 MJ digestible energy kg -1 diet day -1 .

Growth and energy budget of juvenile lenok Brachymystax lenok in relation to ration level

“…Previous studies have reported two main types of growth-ration relationships: a simple linear regression (Niimi and Beamish, 1974;Cui et al, 1996; and, more commonly, an increasing but decelerating curve (Jobling, 1994;Han et al, 2004;Khan and Abidi, 2010). In the present study, the growth-ration relationship over the whole ration range was represented by a decelerating curve and the conversion effi ciency was highest at an intermediate ration level.…”

“…A typical growthration relationship for fi sh is represented by a decelerating curve (Brett and Groves, 1979;Han et al, 2004;Khan and Abidi, 2010), but studies have also shown that linear relationships are common (Sullivan, 1982;Cui et al, 1996;Zhang et al, 2011).…”

“…The relationship between growth rate and RL in fi sh is very important for the commercial success of any aquaculture venture because feed accounts for the majority of the total production costs (Khan and Abidi, 2010). However, it is also important to determine feed conversion effi ciency, which is essential for evaluating energy fl ow between trophic levels in natural aquatic communities (Penczak et al, 1984;Armstrong and Hawkins, 2008).…”

Linking fatty acids in the diet and tissues to quality of larval southern flounder (Paralichthys lethostigma)

“…Gross feed conversion efficiency (GFCE) over the entire experiment was calculated for each ration as the change in WW divided by total dry weight of feed delivered to the tank (Stickney, 2005). Since GFCE increases with ration to a point, then decreases as ration exceeds maximum intake, a second order polynomial (quadratic function) was used to model the relationship between GFCE and ration (Zeitoun et al, 1976;Khan and Abidi, 2010). Survival was high for most rations, but decreased linearly with decreasing ration when levels became limiting.…”

Effect of Varying Protein‐to‐Energy Ratios on Growth, Nutrient Retention, Somatic Indices, and Digestive Enzyme Activities of Singhi, Heteropneustes fossilis (Bloch)

“…Although data on some aspects of nutritional requirements of this fish are available (Niamat and Jafri 1984; Akand et al 1991; Anwar and Jafri 1992; Firdaus 1993; Firdaus et al 1994; Firdaus and Jafri 1996; Mohamed 2001; Mohamed and Ibrahim 2001; Firdaus et al 2002; Usmani et al 2003; Khan and Abidi 2009; Siddiqui and Khan 2009; Khan and Abidi 2011a, 2011b), no information is available on its optimum P/E ratio in diets for H. fossilis . This study was, therefore, conducted with a view to optimize dietary P/E ratio so that protein and energy balanced, cost‐effective, practical diet could be formulated for the intensive culture of H. fossilis .…”