Comparative study on dietary protein requirements for juvenile and pre-adult gibel carp (Carassius auratus gibelio var. CAS III)

Abstract

Two 8-week growth trials were conducted in indoor recirculation system to evaluate the protein requirements for juvenile (3.70 AE 0.20 g) and pre-adult (85.2 AE 0.70 g) gibel carp, Carassius auratus gibelio var. CAS III. Six isoenergetic diets were formulated for each trial using fish meal and casein as protein sources, and protein level was 250-450 g kg À1 in Trial 1 and 200-450 g kg À1 in Trial 2. With the increasing dietary protein, feeding rate (FR) and feed conversion ratio (FCR) significantly decreased (P < 0.05). Weight gain (WG) increased first and then reached a plateau in 330-450 g kg À1 in Trial 1 (P > 0.05), while decreased after the maximum value in 350 g kg À1 in Trial 2 (P < 0.05). Productive protein values (PPVs) were lower in 370-450 g kg À1 in Trial 1 and 400-450 g kg À1 in Trial 2 (P < 0.05). Increasing dietary protein level increased protein content and decreased lipid content in whole fish body and white muscle (P < 0.05). Apparent digestibility coefficient of dry matters (ADC d ) decreased, while apparent digestibility coefficient of protein (ADC p ) increased in 370-450 g kg À1 in Trial 1 and 250-450 g kg À1 in Trial 2 (P < 0.05). Trypsin activity significantly increased in 370-450 g kg À1 in Trial 1 (P < 0.05) and was not affected in Trial 2 (P > 0.05). Hepatic alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities in both trials increased when dietary protein was above 400 g kg À1 (P < 0.05). Based on quadratic regression of WG, it was estimated that dietary protein requirement for maximum growth was 414 g kg À1 (digestible protein of 376 g kg À1 ) and 365 g kg À1 (digestible protein of 324 g kg À1 ) for juvenile (3.70 g) and pre-adult gibel carp (85.2 g).

Effects of dietary protein levels on the growth, body composition, serum biochemistry and digestive enzyme activity in Chinese rice field eel ( Monopterus albus ) fingerlings

“…Similar result was also found in Nile tilapia Oreochromis niloticus , whose optimal protein level was 30% in immature grow‐out stage and 40% in reproduction stage (Al Hafedh, ; El‐Sayed, Mansour, & Ezzat, ). The result divergences between our study and previous studies on M. albus might be due to the different lipid levels adopted in the diets, as well as the different dietary protein sources, fish strain and experimental environment used (Buzollo et al, ; Ye et al, ).…”

Whole‐body amino acid pattern of juvenile, preadult, and adult pacu, Piaractus mesopotamicus, with an estimation of its dietary essential amino acid requirements

“…In the preset study, body chemical composition was significantly affected by wet body weight among the three growth phases of pacu. According to previous studies, lipid and moisture contents are inversely related (Dumas et al, ; Ye et al, ). In the present study, body lipid content significantly increased with increasing fish size, resulting in reduced moisture content of the fish.…”

“…It is well known that the chemical composition, including the moisture, crude protein, total lipid, and ash content, of fish does not remain constant and changes during the growth phases (Dumas, France, & Bureau, ; Ye et al, ). Sufficient literature is available about the body chemical composition of fish, which shows that it may be influenced by several internal and external factors such as fish size, strain, diet nature, rearing conditions, and season (Brown, ; Caulton & Bursell, ; Groves, ; Love, ; Phillips, Livingston, & Dumas, ; Salam, Ali, & Anas, ; Salam & Davies, ; Ye et al, ). In the preset study, body chemical composition was significantly affected by wet body weight among the three growth phases of pacu.…”

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

“…This optimal protein level is a little lower than that of previous reported in juveniles of red‐spotted grouper ( Epinephelus akaara (Wang et al, 2016), snowtrout ( Schizothorax richardsonii ) (Wagle, Shrestha, Rai, & Pandit, 2016), sharpsnout sea bream ( Diplodus puntazzo , Cetti 1777) (Coutinho, Peres, Guerreiro, Pousão‐Ferreira, & Oliva‐Teles, 2012), gibel carp ( Carassius auratus gibelio var. CAS III) (Ye et al, 2017), grass carp ( Ctenopharyngodon idella ) (Jin et al, 2015), but more closer to yellow catfish ( Pelteobagrus fulvidraco ) (Ye et al, 2010) and zebrafish ( Danio rerio ) (Fernandes, Peres, & Carvalho, 2016). As it belongs to a kind of cyprinoid and being one of the omnivorous aquatic animals, the protein requirement of S. younghusbandi is more similar to zebrafish and yellow catfish.…”