Abstract：
A 60 days study was conducted to evaluate the physiological response of indigenous species Labeo rohita (LR) and indigenous predator Chitala chitala (CC) in presence of an invasive species Piaractus brachypomus (PB). Two treatment groups as LR + PB (T1) and LR + PB + CC (T2) with individual control groups as T0LR, T0PB and T0CC were designed in triplicates. Fingerlings of LR, PB and CC were randomly distributed into 15 circular tanks with a stocking ratio of 1:1 and 1:1:0.3 in T1 and T2 group, respectively and 10 nos. each of LR, PB and CC in respective control groups. At first 15 min of the experiment, cortisol level was found significantly (P < 0.05) higher in all three experimental fishes in T1 and T2 groups. With the experimental duration, the level of stress hormone (cortisol), oxidative stress enzymes (superoxide dismutase, catalase, and glutathione peroxidase), tissue metabolic enzymes (lactate dehydrogenase and malate dehydrogenase), serum metabolic enzymes (transaminase enzymes) and blood glucose level were significantly (P < 0.05) increased in T1 and T2 groups for LR and CC whereas, no variation (P > 0.05) were observed for PB in both T1 and T2 groups. The total antioxidant capacity (TAC), liver glycogen, total protein, albumin and globulin were found to be significantly (P < 0.05) decreased in LR in the presence of PB and CC. The present study provides a preliminary insight into the biological interaction between native and invasive species and their physiological responses in the presence of native predator with higher trophic index. Thus, the results of the study suggest the superior traits of invasive P. brachypomus try to dominate the other two native species by negatively influencing the native fauna even with a higher trophic index (C. chitala).
摘要：
进行了为期60天的研究，以评估在存在入侵物种Piaractusbrachypomus（PB）的情况下，土著物种Labeorohita（LR）和土著捕食者Chitalachitala（CC）的生理反应。两个治疗组分别为LR+PB(T1)和LR+PB+CC(T2)，单个对照组为T0LR，T0PB和T0CC一式三份设计。LR的鱼苗，在T1和T2组中，PB和CC随机分配到15个圆形水箱中，库存比分别为1：1和1：1：0.3，分别和10个。每个LR，在各自的对照组中的PB和CC。在实验的最初15分钟，在T1和T2组中，所有三种实验鱼类的皮质醇水平均显着升高（P<0.05）。随着实验的持续时间，压力荷尔蒙（皮质醇）的水平，氧化应激酶(超氧化物歧化酶，过氧化氢酶,和谷胱甘肽过氧化物酶），组织代谢酶（乳酸脱氢酶和苹果酸脱氢酶），血清代谢酶(转氨酶)和血糖水平显著升高(P<0.05)T1和T2组的LR和CC,T1和T2组的PB均未观察到变化（P>0.05）。总抗氧化能力(TAC)，肝糖原,总蛋白质，发现在存在PB和CC的情况下，LR中的白蛋白和球蛋白显着降低（P<0.05）。本研究提供了在营养指数较高的天然捕食者存在下，天然和入侵物种之间的生物学相互作用及其生理反应的初步见解。因此，研究结果表明，即使在营养指数较高的情况下，侵入性P.brachypomus的优良性状也试图通过对本地动物区系产生负面影响来控制其他两个本地物种（C.chitala).
