吉富罗非鱼对饲料精氨酸的需要量

Subjects: Biology >> Zoology submitted time 2017-10-23 Cooperative journals: 《动物营养学报》

武文一 蒋明 刘伟 吴凡 田娟 杨长庚 文华

Abstract： This experiment was conducted to study the effects of dietary arginine (Arg) level on growth performance, feed utilization, body composition, serum biochemical indices and non-specific immune indices of genetically improved farmed tilapia (GIFT, Oreochromis niloticus), in order to determine the dietary Arg requirement of GIFT. Six isonitrogenous and isoenergetic semipurified diets (contained 30.21% crude protein and 17.77 MJ/kg gross energy) were formulated with 0.65%, 0.94%, 1.24%, 1.58%, 1.86% and 2.11% Arg, respectively. Each experimental diet was fed to 3 net cages for 60 d, and 15 fish with the initial body weight of (81.52�.00) g in each net cage. The results showed as follows: with the dietary Arg level increasing, the weight gain rate (WGR), specific growth rate (SGR), protein efficiency ratios (PER) and the protein deposition efficiency (PDE) were firstly increased and then decreased which reached their peaks in the 1.58% group, and significantly higher than those in other groups (P<0.05); whereas the feed conversion ratio (FCR) was firstly decreased and then increased which reached the lowest value in the 1.58% group, and significantly lower than that in other groups (P<0.05); the hepatosomatic index (HSI) and viscerosomatic index (VSI) had the same trend with FCR. The change tendency of ash content in muscle and crude lipid content in whole body was similar to FCR with dietary Arg level increasing, but the change tendency of crude lipid content in muscle was similar to WGR and SGR, while the crude protein content in muscle and ash content in whole body were firstly increased with dietary Arg level increasing and then leveled off. Dietary Arg level had no significant effects on the condition factor (CF) and the contents of crude protein in whole body, moisture in whole body and muscle (P>0.05). With the increase of dietary Arg level, the in muscle had no significant differences (P>0.05), while the amino acids (except tyrosine, glycine and alanine), essential amino acid and total amino acid contents in muscle were firstly decreased and then increased. Dietary Arg level significantly affected the activities of aspartate transaminase (AST), alanine aminotransferase (ALT) and the contents of total protein (TP), urea nitrogen (UN), total cholesterol (T-CHO), glucose (GLU) and triglycerides (TG) in serum (P<0.05), and significantly affected the activities of total superoxide dismutase (T-SOD), total nitric oxide synthase (T-NOS) and lysozyme (LYZ) in liver and serum (P<0.05). With regarding the WGR, FCR and PER as the evaluation indicators, the quadratic regression analysis shows that the dietary Arg requirement of GIFT is 1.51% to 1.58% of diet or 4.99% to 5.25% of dietary protein.

 Hits 3531  Downloads 2606  Comment 0