Search

The present study was conducted to determine the dietary folic acid ( FA) requirement of genetically improved Nile tilapia, Oreochromis niloticus. Experimental diets were supplemented with 0.04, 0.22, 0.48, 0.96, 2.25, or 4.07 mg/kg FA, respectively, and fed to three replicate groups of 15 tilapia (mean initial weight = 60.23 ± 2.60 g; mean ± SD) for 12 weeks. Results showed that the weight gain rate increased linearly with increasing dietary FA from 0.04 to 0.40 mg/kg, then remained stable with higher supplementation. Similarly, hepatic FA concentration, red blood cell count ( RBC), hemoglobin concentration ( HB) and hematocrit ( HCT) all markedly increased in fish fed with 4.07 mg/kg FA compared to those fed a control diet ( p < .05). Serum aspartate aminotransferase ( AST) and alanine aminotransferase ( ALT) activities decreased with increasing dietary FA ( p < .05). The FA requirement was estimated to be 0.4 mg/kg based on weight gain rate, and 0.7 mg/kg based on liver FA accumulation. [ABSTRACT FROM AUTHOR]

The study investigated the effects of different dietary lipid sources on the growth performance, carcass composition, and blood parameters of juvenile Chinese sturgeon, Acipenser sinensis. Seven iso-nitrogenous and iso-energetic diets containing different lipid sources were prepared, i.e. fish oil ( FO), soybean oil ( SO), groundnut oil ( GO), rapeseed oil ( RO), corn oil ( CO), pork lard ( PL), or fish oil: pork lard (1 : 1, FPL). Each experimental diet was fed to triplicate treatments of eight Chinese sturgeon juveniles with initial weights of approximately 47.5 g in indoor tanks for 10 weeks. The FO, SO, and CO treatments had significantly higher weight gain and specific growth rates than the other treatments. Muscle lipid content of the FO treatment was significantly higher than that of the PL treatment, but significantly lower than that of the SO treatment (P < 0.05). The PL treatment had the lowest liver lipid content. Plasma cholesterol and triglyceride concentrations in the CO, FO, and SO treatments were significantly lower than those in the GO, PL, and FPL treatments. The activities of alanine aminotransferase and aspartate transaminase in the FO, GO, and CO treatments were lower than those in the SO, PL and FPL treatments (P < 0.05). This study revealed that the use of lipid sources for juvenile A. sinensis can be chosen in the order of FO, followed by CO and SO; GO was the least suitable lipid source for juvenile Chinese sturgeons. [ABSTRACT FROM AUTHOR]