title: Effects of Ala-Gln feeding strategies on growth, metabolism, and crowding stress resistance of juvenile Cyprinus carpio var. Jian.
abstract: The present study was conducted to evaluate the effects of different L-alanyl-l-glutamine (Ala-Gln) feeding strategies on the growth performance, metabolism and crowding stress resistance related parameters in juvenile Jian carp (Cyprinus carpio var. Jian) under crowded condition (80 g/L). Juvenile Jian carp (initial weight 26.1 ± 0.6 g) were distributed into five groups which fed with graded concentrations (0% or 1.0%) of Ala-Gln for eight weeks. Control group (I, 0/0) fed with control diet (0% Ala-Gln) throughout the feeding trial. The other four groups employed different control and experimental diet feeding strategies ranging from two weeks control diet fed and two weeks experimental diet (1% Ala-Gln) fed (II, 0/2) to eight weeks experimental diet fed (V, 4/4). Results revealed that Mean weight gain (MEG) under all different feeding strategies of Ala-Gln were significantly higher than that of the control group (p < 0.05), and MEG of group II (201.90%) was even higher than that of group IV (184.70%). Liver glycogen and blood total protein of groups II, III and V were significantly higher than that in groups I and IV (p < 0.05). The highest level of serum thyroxine (10.07 ng/ml), insulin-like growth factor-I (52.40 ng/ml) and insulin (9.73 μ IU/mL) were observed in group V. However, diet supplemented with Ala-Gln did not affect the levels of serum glucose, cortisol and catecholamine in fish. The mRNA expression of GR1a, GR1b and GR2 were also significantly changed in Ala-Gln supplementation groups compared with control group (p < 0.05). After fish intraperitoneally injected with virulent Aeromonas hydrophila, the fish survival rates were significantly increased in all Ala-Gln supplementation groups compared with control group (p < 0.05). Results from the present experiment showed the importance of dietary supplementation of Ala-Gln in benefaction of the growth performance, metabolism and crowding stress resistance in Jian carp breeding. The optimal feeding strategy was alternatively fed with control diet and then experimental diet at an interval of two weeks for juvenile Jian carp under crowded condition.
authors.affiliation: College of Animal Science and Technology, Jilin Agricultural University, Changchun 130118, China.
authors.forename: Xiu-Mei
authors.initials: XM
authors.lastname: Chen
authors.affiliation: Testing Center of Quality and Safety in Aquatic Product, 777 CaiYu Road, Changchun, Jilin, China.
authors.forename: Gui-Liang
authors.initials: GL
authors.lastname: Guo
authors.affiliation: Testing Center of Quality and Safety in Aquatic Product, 777 CaiYu Road, Changchun, Jilin, China.
authors.forename: Li
authors.initials: L
authors.lastname: Sun
authors.affiliation: College of Animal Science and Technology, Jilin Agricultural University, Changchun 130118, China.
authors.forename: Qiu-Shi
authors.initials: QS
authors.lastname: Yang
authors.affiliation: College of Animal Science and Technology, Jilin Agricultural University, Changchun 130118, China. Electronic address: wangguiqing131@163.com.
authors.forename: Gui-Qin
authors.initials: GQ
authors.lastname: Wang
authors.affiliation: College of Animal Science and Technology, Jilin Agricultural University, Changchun 130118, China.
authors.forename: Gui-Xin
authors.initials: GX
authors.lastname: Qin
authors.affiliation: College of Animal Science and Technology, Jilin Agricultural University, Changchun 130118, China.
authors.forename: Dong-Ming
authors.initials: DM
authors.lastname: Zhang
mesh_terms: D000818:Animals; D017756:Aquaculture / Q000379:methods; D001786:Blood Glucose / Q000032:analysis; D002347:Carps / Q000502:physiology*; D002395:Catecholamines / Q000097:blood; D003441:Crowding; D004032:Diet; D004151:Dipeptides / Q000494:pharmacology*; D029941:Fish Proteins / Q000235:genetics / Q000378:metabolism; D006003:Glycogen / Q000378:metabolism; D018840:HSP70 Heat-Shock Proteins / Q000378:metabolism; D006854:Hydrocortisone / Q000097:blood; D008099:Liver / Q000187:drug effects / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D011965:Receptors, Glucocorticoid / Q000235:genetics; D013312:Stress, Physiological
chemical_list: D001786:Blood Glucose; D002395:Catecholamines; D004151:Dipeptides; D029941:Fish Proteins; D018840:HSP70 Heat-Shock Proteins; D012333:RNA, Messenger; D011965:Receptors, Glucocorticoid; D006003:Glycogen; C054122:alanylglutamine; D006854:Hydrocortisone
keywords: Ala-Gln; Crowding stress; Cyprinus carpio var. Jian; Feeding strategy