Dietary protein requirement for juvenile mandarin fish, Siniperca scherzeri

Abstract

An 8‐week feeding trial was conducted to investigate the dietary protein requirement of juvenile mandarin fish, Siniperca scherzeri, a demersal freshwater piscivore with high commercial value in East Asia. Five isolipidic (100 g/kg) and isoenergetic (20 MJ/kg) practical diets were formulated to contain graded levels of 450, 500, 550, 600, and 650 g/kg crude protein, using mackerel fishmeal as the sole source of protein. Each of the five test diets was fed to visual satiety to triplicate groups of fish (initial mean body weight ± SE; 20.1 ± 0.2 g) reared in a recirculating freshwater system over the experimental period. Fish growth performance in terms of weight gain tended to improve with increasing dietary protein level, and the highest values were observed in those fish fed the 600–650 g/kg diets. Feed intake significantly declined as the protein content of the diet increased. Feed efficiency and protein retention tended to increase with increasing dietary protein levels, from 450 to 600 g/kg, and then declined when dietary protein content further increased to 650 g/kg. A similar trend was also found for the protein efficiency ratio, although the observed changes did not reach statistical significance. Whole‐body composition and plasma biochemical parameters were not significantly affected by the dietary protein content. Based on these findings and a broken‐line model of growth, 614.4 g/kg seems to be the proper amount of protein in a practical diet for >20 g mandarin fish.

Effects of the Feeding Rate on Growth Performance, Body Composition, and Hematological Properties of Juvenile Mandarin Fish Siniperca scherzeri in a Recirculating Aquaculture System

“…2 HSI (%) = 100 × (weight of liver/weight of fish). 3 VSI (%) = 100 × (weight of viscera/weight of fish)]. 4 CVBL (%) i = 100 × (standard deviation of initial length of fish/mean initial length of fish).…”

“…In Korea, China, and Vietnam, fish of the genus Siniperca [1,2] are commercially valuable because the meat is palatable [1][2][3][4]. However, they are challenging to farm with formulated fish feed due to their strong preference for live prey [5,6], and thus the commercial supply of S. scherzeri is limited [4,7].…”

“…However, they are challenging to farm with formulated fish feed due to their strong preference for live prey [5,6], and thus the commercial supply of S. scherzeri is limited [4,7]. Efforts to develop feed formulations for juvenile S. scherzeri by applying the latest feed technologies are continuing [3,[8][9][10].…”

Dietary protein requirement of the high altitude's representative teleost juveniles Schizopygopsis younghusbandi (Cypriniformes: Cyprinidae)

“…Unlike the mammals, protein is mostly used for energy consumption and tissue deposition in fish (Ogino & Saito, 1970). Numerous studies have reported that fish fed low protein diets caused a decrease in growth performance, digestive and absorptive ability, and body protein composition (Einen & Roem, 1997; Jiang et al, 2016; Sankian, Khosravi, Kim, & Lee, 2019). On the contrary, an optimal protein level could improve the growth and maintain the normal physiological metabolism in fish.…”

Total replacement of dietary fish oil with alternative lipid sources in a practical diet for mandarin fish, Siniperca scherzeri, juveniles

“…The growing interest in mandarin fish culture has been triggered by increasing demand on its shrinking wild stock (Wu et al 1997;Chu et al 2013). Yet, so far, there is relatively little scientific information available concerning mandarin fish nutrition (Zhang et al 2009;Lee et al 2012;Sankian et al 2017Sankian et al , 2018Sankian et al , 2019, and its commercial production still relies on expensive live prey. Hence, one of the most important steps in developing and implementing a profitable and sustainable culture practice for this species is to formulate a nutritionally balanced and cost-effective commercial feed.…”