This study investigates the effects of Phyllanthus amarus extract (PAE) on immune responses, growth, and resistance to Vibrio alginolyticus in white shrimp (Litopenaeus vannamei). In vitro PAE treatment did not alter the cell viability of haemocytes and significantly enhanced immune parameters such as phenoloxidase (PO) activity, phagocytic activity, and superoxide anion (O₂⁻) production. We conducted two feeding trials to examine the effects of PAE on the growth, disease resistance, and innate immune parameters of white shrimp. In the first in vivo trial, shrimps (4.01 ± 0.03 g) were fed a diet containing 0 g (control), 10 g (PAE10), 20 g (PAE20), or 40 g (PAE40) of PAE per kilogram of feed for 56 days. After the feeding period, the PAE20 group showed a significantly higher weight gain and specific growth rate than shrimp fed the control diet. Furthermore, after challenge with V. alginolyticus, shrimp fed a diet containing PAE showed significantly higher survival than those fed the control diet. The second in vivo trial (28 days) was performed to identify the mechanisms of enhanced immunity in PAE-fed shrimp. Shrimp fed the PAE20 diet generally had the highest total haemocyte count, PO activity, phagocytic activity, and O₂⁻ production, followed by the PAE40 and PAE10 groups. Thus, our results suggest that administration of 20 g of PAE per kilogram of feed can enhance immunity, growth, and resistance to V. alginolyticus in white shrimp.

这项研究调查了余甘子提取物（PAE）对白色虾（南美白对虾）的免疫反应，生长和对溶藻弧菌的抵抗力的影响。体外PAE治疗不改变血细胞和显著增强的免疫参数，如酚（PO）的活性，吞噬活性，和超氧阴离子（O的细胞活力₂ ^- ）的生产。我们进行了两项饲养试验，以检验PAE对白虾生长，抗病性和先天免疫参数的影响。首次体内在试验中，对虾（4.01±0.03 g）饲喂每千克饲料含有0 g（对照），10 g（PAE10），20 g（PAE20）或40 g（PAE40）PAE的饲料，历时56天。喂食期后，PAE20组的体重增加和比生长速率显着高于喂食对照饮食的虾。此外，在用溶藻弧菌攻击后，饲喂含PAE日粮的虾比饲喂对照日粮的虾显示出更高的存活率。进行了第二次体内试验（28天），以鉴定PAE喂养的虾增强免疫力的机制。虾喂PAE20饮食一般有最高的血细胞总数，PO活性，吞噬活性，和O ₂ ^-生产，其次是PAE40和PAE10组。因此，我们的研究结果表明，每千克饲料施用20 g PAE可以增强白虾的免疫力，生长和对溶藻弧菌的抵抗力。