title: Effect of N-acetyl cysteine and glycine supplementation on growth performance, glutathione synthesis, anti-oxidative and immune ability of Nile tilapia, Oreochromis niloticus.
abstract: An 8-week feeding trial was conducted to evaluate the effect of N-acetyl cysteine (NAC) and glycine supplementation on growth performance, glutathione (GSH) synthesis, anti-oxidative and immune ability of Nile tilapia, Oreochromis niloticus. Four practical diets were formulated, control, control +0.2% NAC, control +0.5% glycine, control +0.2% NAC +0.5% glycine. Each diet was randomly assigned to quadruplicate groups of 30 fish (approximately 9.5 g). The weight gain and specific growth rate were significantly increased with the supplementation of NAC and glycine. While they had no effect on feed efficiency feed intake and survival. Glutathion peroxidase (GPx) was increased by NAC and γ-glutamine cysteine synthase (γ-GCS) in plasma were increased by glycine. After the feeding trail, fish were challenged by Streptococcus iniae, fish fed the diet supplemented with NAC obtained significantly higher survival rate after 72 h challenge test. NAC also decreased malonaldehyde (MDA) in liver, increased glutathione S-transferase (GST) activity in plasma, up-regulated mRNA expression of Superoxide dismutase (SOD) and GPx in liver and headkidney. Dietary supplementation of glycine increased the anti-oxidative ability of tilapia through increase anti-oxidative enzyme activity (SOD, glutathione reductase, myeloperoxidase) and up-regulate anti-oxidative gene expression (SOD). Immune ability only enhanced by the supplementation of NAC through increased interleukin-1β (IL-1β) mRNA expression. These results clearly indicated that the supplementation of NAC and glycine can significantly improve the growth performance of tilapia, and NAC also enhance the anti-oxidative and immune capacity of tilapia, glycine could only enhance the anti-oxidative ability.
authors.affiliation: Institute of Aquatic Economic Animals, School of Life Sciences, Sun Yat-sen University, Guangzhou, China.
authors.forename: Shiwei
authors.initials: S
authors.lastname: Xie
authors.affiliation: Institute of Aquatic Economic Animals, School of Life Sciences, Sun Yat-sen University, Guangzhou, China.
authors.forename: Weiwen
authors.initials: W
authors.lastname: Zhou
authors.affiliation: Institute of Aquatic Economic Animals, School of Life Sciences, Sun Yat-sen University, Guangzhou, China.
authors.forename: Lixia
authors.initials: L
authors.lastname: Tian
authors.affiliation: Institute of Aquatic Economic Animals, School of Life Sciences, Sun Yat-sen University, Guangzhou, China.
authors.forename: Jin
authors.initials: J
authors.lastname: Niu
authors.affiliation: Institute of Aquatic Economic Animals, School of Life Sciences, Sun Yat-sen University, Guangzhou, China. Electronic address: edls@mail.sysu.edu.cn.
authors.forename: Yongjian
authors.initials: Y
authors.lastname: Liu
mesh_terms: D000111:Acetylcysteine / Q000031:analogs & derivatives / Q000032:analysis / Q000378:metabolism*; D000821:Animal Feed / Q000032:analysis; D000818:Animals; D000975:Antioxidants / Q000378:metabolism; D023681:Cichlids / Q000254:growth & development / Q000378:metabolism; D004032:Diet / Q000662:veterinary; D019587:Dietary Supplements / Q000032:analysis; D005393:Fish Diseases / Q000276:immunology* / Q000382:microbiology; D005978:Glutathione / Q000378:metabolism; D005998:Glycine / Q000378:metabolism*; D007113:Immunity, Innate; D013290:Streptococcal Infections / Q000276:immunology / Q000382:microbiology / Q000662:veterinary*; D000070058:Streptococcus iniae / Q000502:physiology
chemical_list: D000975:Antioxidants; D005978:Glutathione; D005998:Glycine; D000111:Acetylcysteine
keywords: Anti-oxidant; IL-1β; Immune response; Oreochromis niloticus; Streptococcus iniae