White Shrimp Litopenaeus vannamei that Have Received Fucoidan Show Protective Immunity after Ammonia Stressing

Abstract

White shrimp Litopenaeus vannamei immersed in seawater (35‰) containing fucoidan at 0 (control) and 200 mg/l for 3 h were exposed to 5 mg/l ammonia-N (ammonia as nitrogen), and immune parameters including hyaline cells (HCs), granular cells (GCs, including semi-granular cells), total hemocyte count (THC), phenoloxidase (PO) activity,and respiratory burst (RBs) were examined 6~24 h post-stress. The GCs, PO activity and RB of shrimp immersed in seawater containing fucoidan at 200 mg/l returned to original values earlier at 12~24 h post-stress, whereas in control shrimp they did not. The HCs and THC of shrimp immersed in seawater containing 200 mg/l fucoidan were significantly higher than those of control shrimp at 12~24 h post-stress. It is concluded that white shrimp immersed in seawater containing fucoidan exhibited a capability for maintaining homeostasis by regulating their cellular and humoral immunity against ammonia stress as evidenced by earlier recovery in immune parameters.白蝦浸泡於含0(對照組)與200 mg/l褐藻多醣的海水經3小時後，暴露於5 mg/l氨-氮6~24小時後，測定免疫因子包含透明球、顆粒球(包含半顆粒球)、總血球、酚氧化酵素活性以及呼吸爆。浸泡於含200 mg/l褐藻多醣海水的白蝦，其顆粒球及呼吸爆於緊迫12~24小時後回復至起始值，對照組則否。浸泡於含200 mg/l褐藻多醣海水的白蝦經氨-氮緊迫後12~24小時，其透明球與總血球顯著高於對照組。證實白蝦經浸泡於含褐藻多醣的海水可藉由調節細胞性與體液性免疫抵抗氨緊迫，其免疫因子回復較早，具維持生物恆定的能力。