The optimal dietary lipid level for golden pompano Trachinotus ovatus fed the diets with fish meal replaced by soy protein concentrate

Abstract

A feeding trial was conducted to determine the optimal dietary lipid level for golden pompano Trachinotus ovatus and the effect of dietary lipid level on fish meal replacement with soy protein concentrate (SPC). Eight isonitrogenous diets were formulated to contain four lipid levels (65 g/kg, 85 g/kg, 105 g/kg and 125 g/kg) and two fish meal levels (280 g/kg and 140 g/kg) respectively. Fish (initial weight 25.2 ± 0.5 g) were fed the test diets in net pens for 7 weeks. At the same dietary fish meal level, weight gain and nitrogen retention efficiency (NRE) tended to increase, while feed intake, feed conversion ratio (FCR) and nitrogen waste tended to decrease, with elevating dietary lipid level from 65 g/kg to 105 g/kg. At the same dietary lipid level, no significant differences were found in weight gain, feed intake, FCR, NRE, condition factor, hepatosomatic index, proximate composition and nitrogen waste between fish fed the diets containing 280 g/kg and 140 g/kg fish meal. This study reveals that the optimal dietary lipid level for golden pompano should be 107 g/kg, and dietary fish meal level could be reduced to 140 g/kg by using SPC as a fish meal substitute. Elevating dietary lipid level could not significantly increase fish meal replacement level with SPC. K E Y W O R D Sdietary lipid level, feed utilization, fish meal, golden pompano, growth, soy protein concentrateresource-limited and expensive protein source. Replacement of fish meal with alternative ingredients in aqua-feed has been regarded as a key for establishing sustainable aquaculture industry (Naylor et al., 2009). Among the plant ingredients used in aqua-feed, soybean has been demonstrated as an excellent protein source due to its high protein digestibility, relative balance of amino acids, huge global production and reasonable market price (Metts et al., 2011; How to cite this article: Ren X, Zhu M, Wu YB, et al. The optimal dietary lipid level for golden pompano Trachinotus ovatus fed the diets with fish meal replaced by soy protein concentrate.

Effects of dietary lipid levels on growth performance, hepatic health, lipid metabolism and intestinal microbiota on Trachinotus ovatus

“…On the contrary, excessive lipid addition in dietary would cause a negative effect on the growth performance of fish (Rainuzzo et al,1997). Wang et al, (2013) had reported that the suitable dietary lipid level for T. ovatus is 65 g/kg, while Ren et al, (2021) reported that 107 g/kg diet lipid is the optimal level for T. ovatus. However, previous studies had deficiency on experimental design: Wang et al, (2013) only focus on two different lipid levels (65 g/kg and 125 g/kg), while the maximum dietary lipid level (125 g/kg) reported by Ren et al, (2021) did not demonstrate the inhibition phenomenon of fish growth performance.…”

“…Wang et al, (2013) had reported that the suitable dietary lipid level for T. ovatus is 65 g/kg, while Ren et al, (2021) reported that 107 g/kg diet lipid is the optimal level for T. ovatus. However, previous studies had deficiency on experimental design: Wang et al, (2013) only focus on two different lipid levels (65 g/kg and 125 g/kg), while the maximum dietary lipid level (125 g/kg) reported by Ren et al, (2021) did not demonstrate the inhibition phenomenon of fish growth performance. Therefore, the optimal lipid level was founded based on the relatively small range of experiment design.…”

“…On the one hand, the experiment carried out by Wang et al, (2013) only concentrated on two different dietary lipid levels (65 g/kg and 125 g/ kg). On the other hand, the maximum dietary lipid level (125 g/kg) reported by Ren et al, (2021) did not demonstrate the inhibition phenomenon of fish growth performance, so we cannot determine whether 125 g/kg dietary lipid is the optimal dietary lipid for T. ovatus. Therefore, different dietary lipid levels from 90 g/kg to 240 g/kg were formulated in the present study to assess the optimal dietary lipid incorporation level of T. ovatus.…”

“…(Xiao et al, 2017;Yan et al, 2015Yan et al, , 2017. Regarding the lipid requirement of Trachinotus ovatus, Wang et al, (2013) had reported that the suitable dietary lipid level for T. ovatus is 65 g/kg, while significantly higher weight gain of T. ovatus fed with 105 g/kg or 125 g/kg dietary lipid compared to 65 g/kg were reported by Ren et al, (2021). On the one hand, the experiment carried out by Wang et al, (2013) only concentrated on two different dietary lipid levels (65 g/kg and 125 g/ kg).…”

Effects of Dietary Lysophosphatidylcholine on Growth Performance and Lipid Metabolism of Juvenile Turbot

“…Turbot is a worldwide important aquaculture fish species, which has a low lipid content in the muscle but a relatively high lipid content in the subcutaneous tissue around the fin [30,31]. The lipid requirement in this fish species is relatively low (around 10%) [32][33][34][35], lower than other marine carnivorous species such as rockfish (Sebastes schlegeli) [36], tongue sole (Cynoglossus semilaevis) [37], and golden pompano (Trachinotus ovatus) [38]. However, use of high-lipid diets is being more and more popular in fish farming practice, in consideration of both the proteinsparing effects of dietary lipid and the pursuit of lipidderived weight gain [39][40][41][42].…”